The Safety of Air Ambulances

CRS Report for Congress
The Safety of Air Ambulances
May 23, 2006
Bart Elias
Specialist in Aviation Safety, Security, and Technology
Resources, Science, and Industry Division

Congressional Research Service ˜ The Library of Congress

The Safety of Air Ambulances
Summary
The estimated rate of air ambulance accidents has been steadily rising since the
early 1990s, and has increased at a rapid rate since 1998 when the industry began to
expand more rapidly and shift toward a model of more independent private air
ambulance services that cover larger geographic areas. Statistics indicate that the
large majority of air ambulance accidents are attributable to operational factors
related to pilot situation awareness and decision making when faced with adverse
environmental conditions such as darkness, deteriorating weather, rugged terrain, or
some combination of these factors.
Initiatives to improve air ambulance safety to date have consequently focused
on additional pilot training, implementing risk management practices to improve the
safety of flight operations, and using various technologies to improve pilot situation
awareness in restricted visibility conditions. However, implementation of these
safety measures has strictly been voluntary. The National Transporation Safety
Board (NTSB) and other aviation safety experts are advocating the mandatory use of
formal flight dispatch procedures and risk management practices among air
ambulance operators as well as mandatory installation of terrain warning systems on
air ambulance aircraft. The NTSB also found that many air ambulance accidents
occur when patients are not on board, such as en route to an accident scene. Present
regulations allow air ambulances to operate under a less stringent set of rules with
regards to weather minimums and pilot duty times when not carrying patients.
However, the NTSB believes that air ambulance flights should operate under more
stringent commercial operating rules at all times that medical personnel are carried
on board. Although maintenance issues have been identified in about 20 percent of
all air ambulance accidents, neither the Federal Aviation Administration (FAA) nor
the NTSB has placed any specific emphasis on oversight of operators or repair
stations that maintain air ambulance aircraft. The present emphasis on air ambulance
safety has, instead, been dominated by concerns over flight crew performance and
weather-related factors.
A variety of options are available to improve safety among air ambulance
operators. These options include intensified oversight of air ambulance operators and
regulatory changes to bring all phases of air ambulance operations under the same set
of operational rules regarding weather minimums and pilot duty times; possible
regulatory changes to provide for sharing and analysis of safety-related data and
observations with some degree of impunity; possible aircraft design considerations
to improve crash survivability; expanded application of system safety and formal
risk management principles to mission planning and flight operations; enhanced
training for both pilots and support personnel and operational procedures to improve
coordination and situation awareness among the entire air ambulance crew and
ground support team; and the use of various technologies to improve pilot situation
awareness and augment pilot vision in low visibility conditions.
This report will not be updated.

Contents
An Analysis of Air Ambulance Safety Data.............................1
The Role of Air Ambulances.........................................5
State of the Air Ambulance Industry...................................7
Causes of Air Ambulance Crashes.....................................9
Interaction Between Pilots and Flight Conditions................10
Pilot Situation Awareness of Weather Conditions...............11
Mission Pressures........................................11
Conditions in the Flight Environment.........................13
Mechanical Failures and Maintenance Related Crashes...........14
Options for Improving Safety.......................................14
Regulatory Standards and Oversight..............................14
Conducting Special Emphasis Inspections.....................15
Applying Consistent Regulatory Requirements During All Phases of
Operation ...........................................16
Addressing Concerns Over Pilot Fatigue.......................16
Increasing Maintenance Oversight............................18
Improving Aircraft Crashworthiness..........................18
Implementing System Safety and Risk Management Principles.........19
Training and Procedures for Flight and Medical Crews ...............20
Technology to Improve Safety in Low Visibility Conditions ..........22
Terrain Warning Systems...................................23
Technologies to Enhance In-Flight Visibility...................23
List of Figures
Figure 1. Three-Year Moving Average of Estimated Overall and Fatal Accident
Rates for Helicopter Air Ambulance Operations......................3
Figure 2. Factors in Helicopter Air Ambulance Accidents
(1991 -2004).................................................10

The Safety of Air Ambulances
Air ambulances that conduct emergency medical service operations and other
medical-related transport services include both helicopter emergency medical
services (HEMS) that primarily conduct scene response transport of trauma patients
and fixed-wing aircraft operations that primarily conduct inter-facility transports of
critical care patients. The air ambulance industry has grown significantly over the
past 25 years and is widely regarded as having a beneficial effect on improving the
chances of survival and recovery for trauma victims and other critical patients,
especially in rural areas. However, during this time, the air ambulance industry has
been the focus of two in-depth National Transporation Safety Board (NTSB) special
safety studies and numerous other investigations by aviation safety researchers that
have pointed to continued concerns over the safety of its flight operations,
particularly among helicopter air ambulance operators. Although the air ambulance
industry and Federal Aviation Administration (FAA) regulators have taken some
positive steps to address continued concerns over operational safety, the NTSB and
some other aviation safety experts have voiced concerns that not enough has been
done to reduce the risk of accidents in air ambulance operations.
This report analyzes available air ambulance safety data, examines the current
state of the air ambulance industry and factors that may influence safety within the
industry, assesses causal factors underlying the recent spate of air ambulance crashes,
and discusses some available options for improving safety.
An Analysis of Air Ambulance Safety Data
A recent increase in the number of crashes involving air ambulances has raised
concerns among aviation safety experts. According to a National Transportation
Safety Board (NTSB) special study focusing on aviation emergency medical
operations released in January 2006, 55 crashes involving air ambulances occurred¹
in the United States between January 2002 and January 2005. The NTSB noted that
this number of crashes has not been seen since the 1980s. Given that the current air
ambulance fleet is estimated to consist of about 750 helicopters and 150 fixed wing
aircraft,² each year over the past three years, about one in every 50 helicopter air
ambulances has been involved in a crash. An article in USA Today offered the
following stark analogy: “If commercial airlines lost the same proportion of large

¹ National Transportation Safety Board, Special Investigation Report on Emergency Medical
Service Operations. NTSB/SIR-06/01.
² Foundation for Air-Medical Research & Education (FARE), Air Medicine: Accessing the
Future of Health Care, Alexandria, VA: FARE, 2006.

passenger jets as air ambulance companies lost helicopters, 90 airliners would crash
each year.”³
Because there is no centralized database of flight records for the air ambulance
industry, no one knows for sure if safety is eroding or if this increase in accidents can
be explained by the large growth in the use of helicopters and airplanes for medical
evacuation and patient transport. The NTSB notes that while industry estimates
suggest that the number of hours flown by air ambulances has increased by about
85% over the past 15 years, the estimated accident rate for helicopter air ambulances
has also risen from 3.52 accidents per 100,000 flight hours between 1992 and 2001
to 4.56 accidents per 100,000 flight hours between 1997 and 2001.⁴ The NTSB,
however, did not provide its own estimates of accident rates or more recent figures
on the annual accident rates for air ambulances.
Available accident statistics and analyses reviewed by CRS have focused on
helicopter air ambulance operations, which make up more than 80% of the air
ambulance fleet. Consequently this report concentrates on safety data and finding
related to helicopter air ambulances, although many of the issues and observations
may be more broadly applicable to both helicopter and fixed-wing air ambulances.
While much of the flight hour data to substantiate accident rate statistics for air
ambulance operations remains sketchy, CRS analyzed helicopter air ambulance
safety data and computed accident rates using accidents between 1991 and 2004
identified in the 2006 NTSB special study report, and accident data and industry
estimates of hours flown by helicopter air ambulance operators cited in a
comprehensive safety review and risk analysis of air ambulance accidents published
by the Air Medical Physician Association (AMPA).⁵ This analysis estimated that the
overall accident rate among air ambulance operators from 1991 to 2004 to be 3.50
accidents per 100,000 flight hours and the fatal accident rate to be 1.13 accidents per
100,000 flight hours. Looking only at the data since 1998 when a notable spike in
accidents was first observed, the estimated overall accident rate rose to an average
of 4.75 accidents per 100,000 flight hours and the estimated fatal accident rate
increased slightly to 1.25 accidents per 100,000 flight hours. Three-year moving
averages of the estimated accident rate were computed across the 14 year period

³ Alan Levin and Robert Davis, “Surge in Crashes Scars Air Ambulance Industry.” USA
Today, July 18, 2005, A1.
⁴ Ibid. See also Ira J. Blumen, M.D., and the University of Chicago Aeromedical Safety
Committee, A Safety Review and Risk Assessment in Air Medical Transport, 2002, Air
Medical Physicians Association, Salt Lake City, UT.
⁵ CRS analysis of annual accident data and flight hour estimates provided in National
Transportation Safety Board, Special Investigation Report on Emergency Medical Service
Operations and Ira J. Blumen, M.D., and the University of Chicago Aeromedical Network.
A Safety Review and Risk Assessment in Air Medical Transport, 2002. Note: for 2002
through 2004, CRS interpolated estimated flight hours based on industry flight hour
estimates provided for previous years and an estimate of 300,000 hours flown in 2005 cited
in the NTSB report. This yielded an average annual increase in flight hours between 2001
and 2004 of roughly 9.3%.

based on available flight time estimates and are shown in Figure 1.⁶ The trend in the
three-year moving average accident rates suggests a steady increase in the accident
rate from 1991 through 2003, with a slight reversal of this trend in 2004. The data
also show a slight rise in the fatal accident rate over the past five years. While these
data demonstrate an increase in helicopter air ambulance accident rates, particularly
since 1998, they cannot be regarded as conclusive because of the lack of reliable data
on the overall number of hours flown. However, these data, based on best available
information, strongly suggest that there is cause for concern regarding the safety
trend for air ambulance operations.
Figure 1. Three-Year Moving Average of Estimated Overall and Fatal
Accident Rates for Helicopter Air Ambulance Operations

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Year
All AccidentsFatal Accidents
Sources: CRS analysis of annual accident data and flight hour estimates provided
in National Transportation Safety Board, Special Investigation Report on
Emergency Medical Service Operations. NTSB/SIR-06/01 and Ira J. Blumen,
M.D., and the University of Chicago Aeromedical Network. A Safety Review and
Risk Assessment in Air Medical Transport, 2002, Air Medical Physicians
Association, Salt Lake City, UT. Note: A three-year moving average computes
the accident rate using the data from the current year and the two prior-years.
There are two key concerns regarding these accident rate estimates. First, the
trend shows a steady increase in estimated accident rates over the past 14 years, with
⁶ A three-year moving average, sometimes referred to as a three-year rolling average, is an
accident rate calculation based on accidents and flight hours during the referenced year and
the two prior years. So, for example, the data points for 1993 are based on accidents and
flight hour estimates for 1991, 1992, and 1993. This is done to provide a more stable metric
for analyzing trends among accident rates that may fluctuate significantly from year to year.

a more marked increased since 1998. Second, these estimated accident rates are
notably higher than many other commercial aviation sectors. In particular, over the
same period (from 1991-2005), non-scheduled air taxi operators, which fly under the
same rules as air ambulance operators carrying patients, experienced an overall
accident rate of 2.52 accidents per 100,000 flight hours and a fatal accident rate of

0.67 fatal accidents per 100,000 flight hours.⁷ While air ambulance operations,

particularly helicopter air ambulance operations, by their nature may arguably be
inherently more risky than other commercial aviation operations, the relatively higher
estimated accident rates coupled with the observed trend of increasing accidents and
estimated accident rates suggests that the causes of these accidents and possible
options to reduce these numbers is an appropriate topic for policy analysis.
When the NTSB previously examined commercial emergency medical service
helicopter operations in 1988, it estimated that the overall accident rate between 1980
and 1985 was 12.34 per 100,000 flight hours, almost twice the estimated accident
rate experienced by non-scheduled helicopter air taxis during that period.⁸ Moreover,
the fatal accident rate of 5.40 per 100,000 flight hour for helicopter air ambulances
between 1980 and 1985 was estimated to be about 3 ½ times the fatal accident rate
for non-scheduled helicopter air taxis and all turbine-powered helicopters.⁹ While
more recent accident rate estimates among helicopter air ambulance operators have
been climbing steadily, they still appear to be much lower than estimates for the early
1980s. However, the lower observed accident rates in the early 1990s suggest that
safety improvements can be made in air ambulance operations to reduce the overall
and fatal accident rates compared to recently observed levels. Specifically, between
1991 and 1995, the helicopter air ambulance industry had an estimated 1.81 accidents
and 0.91 fatal accidents for every 100,000 flight hours, accident rates that closely
resemble those of other commercial aviation operations such as the previously cited
statistics for non-scheduled air taxi operators. Arguably, based on these data, the
helicopter air ambulance industry has already demonstrated that it can achieve a
better safety record than what it has experienced since 1998.
Although air ambulance operations can be inherently riskier than other aviation
operations because the environment in which they operate is more dynamic and
unpredictable, some experts have raised concerns that the air ambulance industry and
the FAA are simply accepting a higher accident rate than other areas of the aviation
industry rather than taking steps to reduce the number of accidents.¹⁰ While the FAA
and the air ambulance industry have acknowledged that ongoing safety concerns

⁷ Both non-scheduled air taxi operators and air ambulance operations with patients on board
are conducted under Title 14 Code of Federal Regulations, Part 135. CRS calculations
based on data provided in: National Transportation Safety Board, Accidents, Fatalities, and
Rates, 1986 - 2005, 14 CFR Part 135, Nonscheduled Service (On-demand Air Taxis).
⁸ Non-scheduled helicopter air taxi are operated under Title 14 Code of Federal Regulations,
Part 135 and generally do no include local air tours that are exempt from operating under
this set of regulations.
⁹ National Transportation Safety Board, Commercial Emergency Medical Service Helicopter
Operations, NTSB/SS-88/01.
¹⁰ Alan Levin and Robert Davis, “Surge in Crashes Scars Air Ambulance Industry.”

exist, critics argue that their actions to date — largely consisting of advisory
materials and recommendations requiring only voluntary compliance by operators —
are inadequate. To further assess the root causes of air ambulance accidents and
assess possible policy changes to improve safety in the air ambulance industry, it may
be beneficial to examine the operational role of air ambulances as well as the current
state of the air ambulance industry and management practices in the air ambulance
industry.
The Role of Air Ambulances
When most people think of an air ambulance operation they are likely to first
consider helicopter transports of trauma patients, such as car accident victims. This
has historically been the predominant form of air ambulance service since its
beginnings in the early 1970s. Large scale use of air evacuation of wounded troops
was demonstrated to be an effective means of reducing combat mortality both in the
Korean and Vietnam conflicts. Based on this experience, civilian air ambulance use
in the United States began on a small scale starting in the early 1970s and has grown
significantly since. Although some studies have found little or no benefit from
helicopter evacuations of civilian trauma patients, numerous studies point to
improved chances for recovery and significant reductions in mortality rates when air
ambulance services are made available to trauma patients.¹¹ Medical theory and
practice holds that providing critically injured patients with surgical intervention
within the first hour after injury – the so-called “Golden Hour” – can significantly¹²
improve the chances for survival and recovery. In practice, air ambulances,
particularly helicopters, can play an important role in this intervention by providing
rapid patient transport to trauma centers where they can be effectively treated, and
in some cases providing advanced life support capabilities en route. The availability
of this service provides an important role, especially in rural communities that lack
readily accessible advanced care facilities and medical specialists.
More recently, there has been increased utilization of air ambulances, both
helicopters and airplanes, for both on-scene response and inter-facility transport of
critical cardiac patients and stroke victims. Both helicopters and fixed-wing aircraft
are also utilized for other inter-facility transfers to give patients access to specialty
care facilities and medical specialists. While the on-scene response of a helicopter
at a traffic accident is probably what first comes to mind when the term air
ambulance is used, today about 54% of all air medical transports are from hospital
to hospital, while on-scene responses make up 33%. The remaining 13% include
organ and medical supply and speciality medical team transports.¹³ Air ambulances
can also play an important role in emergency evacuation of critical care patients and

¹¹ Association of Air Medical Services (AAMS), AAMS Brief – Part 3: Air Medical
Research and What It Shows. Alexandria, VA: AAMS; National Transporation Safety
Board, Commercial Emergency Medical Service Helicopter Operations; Foundation for Air-
Medical Research & Education (FARE), Air Medicine: Accessing the Future of Health
Care.
¹² Foundation for Air-Medical Research & Education (FARE), Air Medicine.
¹³ Ibid.

transport of medical supplies and staff to disaster areas, as was demonstrated in the
aftermaths of Hurricanes Katrina and Rita in 2005.¹⁴
While some critics assert that air ambulance transports are being over utilized,¹⁵
there is generally widespread acceptance of the benefit provided by both the general
public and the medical community. The air ambulance community acknowledges
that utilization of air ambulances in some cases may, in retrospect, prove to have
been unnecessary. This, they argue, is to be expected if the medical community is
to assure that the maximum number of patients who could potentially benefit from
air ambulance services are provided with this service. Over the past 15 years,
guidelines for air medical dispatch have been refined by the air ambulance
community and emergency room physicians. These various guidelines set forth
circumstance-specific and patient-specific criteria for decision makers assessing
whether to dispatch a flight as well as for analysts reviewing and modeling utilization
and refining resource allocation across a particular geographic area.¹⁶ The industry
also argues that while air ambulance services are comparatively costly when
examined on a single-case basis, appropriately used air medical transport is cost-
effective on a system-wide basis, largely due to more efficient coverage of large
geographic areas, reduced patient transport times, and more rapid intervention that
can reduce overall patient care costs.¹⁷ In general, air ambulance services have
garnered wide community support and endorsement from the medical community as
being a beneficial and cost-effective service for improving access to critical health
care and increasing the chances of survival and recovery for trauma victims and
critically ill patients, particularly in areas where access to specialized health care is
limited. Consequently, air ambulance utilization is likely to continue its steady
growth throughout the United States, particularly in rural areas. This expectation of
continued growth for the industry draws particular attention to the ongoing safety
concerns, because continued growth without any improvement to safety could trigger
widespread public concern over the safety of these operations which has already been
evidenced to some degree based on recent media coverage of the issue.¹⁸
State of the Air Ambulance Industry
The civilian air ambulance industry can trace its origins back to the early 1970s
with the creation of the Maryland State Police aviation program in 1970 and the first
hospital-based medical helicopter service at St. Anthony’s Hospital in Denver,
Colorado in 1972. Prior to then, police departments in the 1960s and early 1970s had

¹⁴ Ibid. Note: Unlike other helicopters and aircraft used in search and rescue (SAR) and
relief missions during natural disasters, dedicated air ambulances are specially equipped and
staffed for transporting sick and injured patients. This report only discusses safety data and
issues for dedicated air ambulance aircraft.
¹⁵ Barry Meier. “Crashes Start Debate on Safety of Sky Ambulances.” The New York
Times, February 28, 2005.
¹⁶ Foundation for Air-Medical Research & Education (FARE), Air Medicine.
¹⁷ Ibid.
¹⁸ See especially Barry Meier. “Crashes Start Debate on Safety of Sky Ambulances” and
Alan Levin and Robert Davis, “Surge in Crashes Scars Air Ambulance Industry.”

used helicopters on occasion to transport critical patients, but provided very limited
en route patient care. The air ambulance industry gradually grew during the 1970s
and by 1980 included 32 helicopter emergency services flying 39 helicopters. During
the 1980s, the industry grew fivefold and by 1990 included 174 helicopter emergency
services and 231 helicopters. The industry experienced continued growth in the
1990s expanding to 231 helicopter emergency services flying 400 helicopters by

2000.¹⁹

A variety of factors, including increases in Medicare reimbursement rates for air
ambulance services and recent declines in available emergency medical and advanced
patient care services in rural areas, have resulted in a significant growth in the air
ambulance industry over the past five years. In 2005, there were 272 helicopter
emergency services flying 753 helicopters in the United States, roughly an 88%
increase in the number of helicopter air ambulances compared to the size of the
industry in 2000. In 2005, there were also an estimated 150 fixed-wing airplanes
dedicated to air ambulance operations used mostly for inter-hospital transfers.²⁰
Based on industry flight hour estimates, growth in the use of air ambulances has been
increasing at a rate of about 4.5% per year over the past 15 years, and most observers
believe that this steady growth in both the size of the dedicated air ambulance fleet
in the United States and the utilization of air ambulances will continue over the next
several years.
While some states and municipalities and other public agencies operate air
ambulances as public aircraft, most air ambulance services are privately owned and
operated, either directly by a hospital or hospital consortium or by private aviation
medical service providers. The Maryland State Highway Patrol has a comprehensive
helicopter air ambulance capability that covers the entire state, while the California
Highway Patrol and the Virginia and Delaware State Police provide air ambulance
services in portions of those states. Several county police forces and emergency
medical units throughout the United States also perform air ambulance missions.
Also, federally operated aircraft provided by the U.S. Coast Guard in Alaska and the
U.S. Army in Hawaii conduct civilian air ambulance operations. CRS estimates that
federal, state, and local government-operated aircraft currently account for about 10%
of air ambulance operations in the United States. However, private operators make
up the large majority of air ambulance services across the United States.²¹ Unlike
aircraft that are operated by a state or local agency which are considered public
aircraft and therefore not under direct FAA oversight, air ambulances operated by
private companies are regulated by the FAA, and therefore have been the focus of
safety studies examining safety within the industry and the FAA’s actions to monitor
and regulate safety.²² These private aviation medical providers may operate under

¹⁹ Foundation for Air-Medical Research & Education (FARE), Air Medicine.
²⁰ Ibid.
²¹ See the Association of Air Medical Services (AAMS), Atlas & Database of Air Medical
Services (ADAMS). AAMS National Office, Alexandria, VA for a comprehensive
geographic database of air ambulance service coverage across the United States.
²² CRS is not aware of any study examining the safety of public aircraft used as air
(continued...)

direct contract providing aircraft and flight crews to a specific hospital or hospital
consortium, or as is becomingly increasingly more common, may act more as a
independent entity with affiliations with various hospitals over a large geographic
region.
In the late 1990s, regulatory changes requiring ambulance services, including
air ambulances, to bill patients separately from hospital charges as well as increases
in Medicare reimbursement for air ambulance flights in some regions, brought about
significant changes to the industry.²³ Most helicopter emergency medical services
in the 1980s and early 1990s were either run directly by hospitals and emergency
facilities or, more commonly, operated under hospital-managed contracts with
aviation companies that provided the helicopters and pilots.²⁴ Today, many of these
services are now operated by stand-alone, private entities with hospital affiliations,
and in many locations, there is direct competition between air ambulance service
providers within a region.
While some states and local governments provide air ambulance services as a
public good or quasi-public good, privately-run operations are far more common.
The Maryland State Police Aviation Command, as an example of a state-run system,
derives about two-thirds of its funding from automobile registration fees and the
remainder from general state treasury funding for the state police. Patients are
consequently not required to pay for transport and medical costs provided by this
service. In the privately-operated air ambulance model, by contrast, patients or their
insurers are directly billed for charges incurred for air ambulance transport. Although
privately-operated air ambulance services provide an important function in the
communities they serve, critics argue that the financial pressures associated with
operating these services as well as insufficient regulatory requirements and oversight
may be significant factors that could negatively affect flight safety across the
industry.
Although competition and associated pressures to conduct missions was already
present when the NTSB examined air ambulance helicopter safety in 1988, it was
generally concluded that helicopter patient transport at that time was not profitable
on the basis of transportation alone. In fact, a 1986 survey cited by the NTSB found
that patients were, on average, only charged for about 75% of the direct cost of air
ambulance transport.²⁵ Hospitals made up for these losses through charges for other
advanced care services provided at the hospital. Thus, the competition that existed

²² (...continued)
ambulances or any study comparing safety between private air ambulance operators and
those operated by state and local government entities.
²³ Barry Meier, “Crashes Start Debate on Safety of Sky Ambulances.” The New York Times,
February 28, 2005. Also see, Title 42 Code of Federal Regulations, Part 414, Subpart H:
Fee Schedule for Ambulance Services.
²⁴ Ibid. See also, National Transportation Safety Board, Safety Study: Commercial
Emergency Medical Service Helicopter Operations.
²⁵ National Transportation Safety Board, Safety Study: Commercial Emergency Medical
Service Helicopter Operations.

in the 1980s was largely between hospitals. From a business perspective, air
ambulances, at that time, were largely seen as a marketing tool to increase public
recognition of the hospital within the community and attract patients. In the current
environment, however, the competition appears to be more directly related to the
flight mission as the business model for most private-sector air ambulance services
has been shifting toward stand-alone operators that market their services to local
hospitals, emergency officials, and even to the general public.²⁶ One example of
marketing to the general public is the sales of yearly “memberships” that will cover
any gaps not paid by insurance for air ambulance transports.²⁷ Various competitive
pressures, including direct competition among services and the desire to satisfy
hospital and emergency medical service administrators that oversee air ambulance
contracts, can potentially affect flight safety if they factor into decisions regarding
whether to accept or continue a flight mission. Operating air ambulances as private
businesses may also create financial pressures that could lead some operators to
forego safety improvements or enhancements that are not specifically required in
order to keep operational costs at a minimum. These various operational pressures
that exist in the air ambulance industry and their potential impact on safety will be
considered in greater detail along with other possible causal and contributing factors
in air ambulance crashes.
Causes of Air Ambulance Crashes
The large majority of air ambulance accidents occur due to a chain of
circumstances involving pilot decision-making and performance and flight
conditions such as weather and terrain. In particular, darkness, reduced visibility, and
rising terrain present significant challenges and risks to air ambulance operators –
particularly helicopter operators – and are often cited as causal factors in accidents.
Pilot knowledge or “situation awareness” regarding weather conditions and terrain
has also been found to be a significant factor in a large number of air ambulance
accidents.
CRS analyzed a database of 120 helicopter air ambulance accidents compiled
by the Helicopter Association International that occurred between 1991 and 2004.
Causal factors were categorized based on brief descriptions of the accident
circumstances and weather conditions provided in this database. The results of this
analysis are shown in Figure 2.

²⁶ Barry Meier, “Crashes Start Debate on Safety of Sky Ambulances.”
²⁷ Ibid.

Figure 2. Factors in Helicopter Air Ambulance Accidents
(1991 -2004)

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Source: CRS analysis of accident synopses provided in Helicopter Association
International, Air Medical Service Accidents, 1991 thru 1994, Alexandria, VA.
Note: CFIT: Controlled Flight into Terrain; ADM: Aeronautical Decision
Making; SA: Situation Awareness; VFR into IMC: Visual Flight Rules into
Instrument Meteorological Conditions. Percentages sum to more than 100%
because many accidents were assigned to more than one causal factor.
Interaction Between Pilots and Flight Conditions. The interplay
between the pilot or flight crew (the operator) and environmental factors such as
weather and terrain played a part in roughly 80% of the accidents examined. This
finding closely matches other analyses examining the causes of air ambulance²⁸
crashes. One of the most common causal factors in these accidents, cited in 27.5%
of the crashes, was what aviation safety experts refer to as controlled flight into
terrain (CFIT), a broad category that generally involves a loss of situation awareness
regarding surrounding terrain, often in poor visibility or at night. The other most
cited factor, also identified in 27.5% of the accidents, was aeronautical decision
making and situation awareness (ADM/SA), which refers to a pilot’s knowledge of
factors affecting the safety of flight and the ability to evaluate risk based on these
factors and make appropriate informed decisions. Another contributor to helicopter
air ambulance crashes, related to errant pilot decision making, is continuing a flight
using outside visual references as is permissible under visual flight rules (VFR) into
²⁸ See Ira J Blumen, M.D., and the University of Chicago Aeromedical Safety Committee,
A Safety Review and Risk Assessment in Air Medical Transport.

poor weather and visibility conditions, known to aviators as instrument
meteorological conditions (IMC). Continued VFR into IMC, as it is referred to by
air safety experts, was cited as a causal factor in 9% of helicopter air ambulance
crashes. Other pilot-related factors cited in a number of accidents included loss of
aircraft control, pilot technique, and visual illusions, all factors that frequently crop
up in poor visibility conditions when a pilot loses visual reference to the horizon or
the ground below and is unable to effectively transition to flight solely by reference
to cockpit instruments. These flight operational factors are a central concern and
have been the focus of the NTSB’s safety recommendations regarding air ambulance
operations as well as the efforts of the FAA and the air ambulance industry to
encourage voluntary implementation of systems safety and risk management concepts
in air ambulance operations.
Pilot Situation Awareness of Weather Conditions. In its most recent
review of air ambulance safety, the NTSB found that situation awareness can often
be lacking in air ambulance operations for a variety of reasons, but was chiefly
concerned with the lack of formal flight dispatch procedures among operators. Air
ambulance pilots lack the benefit of consistent, comprehensive flight dispatch
procedures and often rely on emergency (911) dispatchers, referred to in the industry
as communications specialists, or emergency medical personnel that typically have
no formal training in flight dispatch procedures. In 11 of the 55 accidents reviewed
by the NTSB in their 2006 special study, incomplete or missing information
regarding weather, route of flight, and coordination with on-scene rescue personnel
factored into the causal chain of the accident. The NTSB, consequently,
recommended that the FAA require air ambulance operators to use formalized
dispatch and flight-following procedures that include up-to-date weather information²⁹
and assistance in flight risk assessment decisions. In response to this
recommendation, policymakers might opt to assess the benefits and costs of
implementing formal flight dispatch procedures and specific training in these
procedures to both flight crews and ground communication specialists in the
emergency medical field that coordinate and dispatch air ambulance missions.
Mission Pressures. Aviation safety experts have also pointed to pressures
to complete the mission as factors that can lead to poor judgment among air
ambulance pilots and contribute to accidents. In 1988, the NTSB found that mission
pressures could be exacerbated by a lack of on-site supervision among operators,
particularly those operators that service a broad geographic area. In many of these
instances, the NTSB found that a pilot’s immediate supervisor was not located at the
pilot’s base station or hospital, and in some cases, was located in a distant city. The
NTSB concluded that isolation from management forces pilots to look for structure
and guidance from other sources, particularly hospital emergency service
administrators and personnel. This arrangement can result in pilots placing greater
importance on the medical mission and potentially may compromise sound judgment
with regard to flight safety. The NTSB noted that:

²⁹ National Transportation Safety Board, Special Investigation Report on Emergency
Medical Service Operations.

[h]ospital management, the EMS medical personnel, and the dispatchers can all
intentionally or unintentionally put pressure on the pilots to take a flight in
marginal weather conditions. The reasons for these pressures include
misunderstanding or lack of understanding of weather-related considerations,³⁰
genuine zeal to get a job done, or even competition between EMS programs.
The NTSB also found that, besides the pressures to complete missions based on
medical need influencing flight safety considerations, the relationship between air
ambulance operators and hospitals can play a role in decisions regarding whether to
accept or continue a mission. Pilots may feel pressured to accept or continue
missions in marginal weather conditions in order to satisfy hospital administrators
and maintain good business relations with them. In privately-operated air ambulance
services, the hospital is, in essence, a customer of the air ambulance service, and
pilots may feel compelled to satisfy their customer by accepting and completing a
maximum number of missions. These pressures may be even greater at hospitals and
in regions where there is direct competition among air ambulance providers.
A survey of helicopter air ambulance pilots found that while pressure to accept
or continue missions is a significant concern, pilots more frequently cited pressure
to speed up response time as the most significant pressure factor affecting mission
safety. Internal and external pressures to speed up response time could cause pilots
to miss important risk factors and fail to obtain a full understanding of the weather,
route of flight, obstacles and obstructions en route, and other key pieces of
information during the flight preparation process.
Policymakers may consider options to require specific training and
implementation of risk management techniques for air ambulance operators dealing
with the specific operational environment and operational pressures of the air
ambulance industry. While the FAA has provided a variety of training materials and
resources on aeronautical decision making that are both general in nature as well as
specific to unique considerations for helicopter and air ambulance operations,
decision making and various external pressures that may effect pilot judgment on air
ambulance missions is often not covered in depth during initial and recurrent pilot
training. Therefore, policymakers may consider more formal training and testing of
aeronautical decision making concepts specific to air ambulance operations as a
possible option for mitigating accidents related to poor judgment and decision
making errors.
Besides training in aeronautical decision making, formal techniques for
evaluating the operational risks associated with each flight assignment may benefit
pilots in the decision making process. The FAA has recommended that helicopter
air ambulance operators implement formal operational risk assessment programs to³¹
evaluate flight safety and risk for every mission. The recommended practices
include empowering pilots to be the final decision authority in accepting or declining

³⁰ National Transportation Safety Board, Commercial Emergency Medical Service
Helicopter Operations, p. 17.
³¹ Federal Aviation Administration. FAA Notice N8000.301: Operational Risk Assessment
Programs for Helicopter Emergency Medical Services. August 1, 2005.

a mission assignment; incorporating formal risk assessment tools for gauging the
level of risk on a specific mission; and carrying out a risk mitigation plan to reduce
risks to acceptable levels when feasible. Factors considered in formal pre-flight risk
assessments include weather and visibility conditions; terrain and route of flight;
pilot qualifications, experience ,and fitness for duty; any maintenance issues such as
inoperative equipment; and aircraft performance capabilities and limitations.
Examples of techniques for mitigating risk factors may include more stringent
weather minimums for less experienced pilots; more stringent weather minimums
when certain equipment is inoperative or otherwise unavailable; and the use of
special equipment to improve a pilot’s situation awareness and ability to see and
avoid terrain and obstructions at night and in poor visibility. While the FAA has
issued voluntary guidance to helicopter air ambulance operators set up these risk
management programs, the NTSB has recommended that these flight risk evaluation
programs be made mandatory for all air ambulance operators, and require formal
training in the risk evaluation process for all employees directly involved in flight
missions, not just pilots.³²
Conditions in the Flight Environment. With regard to environmental
conditions, night, weather, obstructions (such as power-lines) and mountainous
terrain, or some combination of these factors was found to have played a role in a
large number of the helicopter air ambulance accidents reviewed by CRS. Presently,
air ambulance operators, for the most part, are not required to equip their aircraft with
instruments that could improve situation awareness regarding height above terrain
and potential terrain collisions, nor are they required to utilize any special equipment
that could enhance visibility at night and in poor weather conditions. While the
FAA, in its guidance to air ambulance operators and inspectors who oversee these
operations issued in January, 2006, identified this equipment as a means to avoid loss
of control and CFIT accidents, it has not required use of this equipment to date.³³
However, the NTSB issued a recommendation to the FAA, based on its 2006 special
study findings, that would specifically require the use of terrain warning systems on³⁴
air ambulances.
Mechanical Failures and Maintenance Related Crashes. In addition
to flight operational factors and conditions of flight, a significant proportion (about
22%) of the helicopter air ambulance accidents examined were found to be
attributable, at least in part, to some type of mechanical failure. This finding roughly
matches that of an earlier comprehensive study looking specifically at maintenance-
related helicopter air ambulance accidents over a 24-year period which concluded
that 23% of all helicopter air ambulance accidents reviewed were maintenance-

³² National Transportation Safety Board, Special Investigation Report on Emergency
Medical Service Operations
³³ Federal Aviation Administration. Helicopter Emergency Medical Services (HEMS) Loss
of Control (LOC) and Controlled Flight Into Terrain (CFIT) Accident Avoidance Programs,
Flight Standards Handbook Bulletin for Air Transportation (HBAT) 06-02A, January 23,

2006.

³⁴ National Transportation Safety Board, Special Investigation Report on Emergency
Medical Service Operations.

related.³⁵ That study found that 50% of helicopter air ambulance crashes attributable
to mechanical or maintenance-related causes were engine related, while 24% were
due to failures of the main rotor drive or transmission, 13% were attributed to
malfunctions of the tail rotor system, and another 13% were attributed to faulty flight
controls. These findings suggest that maintenance of air ambulances poses a
significant safety risk. However, neither the FAA nor the NTSB has identified
maintenance practices among air ambulance aircraft as a specific area for concern.
Consequently, present efforts to prevent air ambulance crashes are focused, instead,
on risk factors associated with flight operations and pilot performance. Available
data suggests that policymakers might also choose to consider a more in-depth
examination of maintenance practices in the air ambulance industry to identify ways
to reduce maintenance-related accidents.
Options for Improving Safety
Based on available data summarized above suggesting that flight operational
factors are the central cause of the large majority of air ambulance accidents, options
for improving safety have focused on possible changes to flight operations and
practices among air ambulance operators. These various options have been framed
in terms of possible alternatives for changing regulatory standards and oversight of
air ambulance operators, incorporating system safety and risk management principles
into the decision making processes regarding air ambulance missions, providing
additional or supplemental training for flight crews as well as medical crews, and
incorporating various technologies to aid pilots and improve safety in low visibility
conditions.
Regulatory Standards and Oversight
Media coverage of air ambulance safety has raised concerns over the degree of
oversight that the FAA has devoted to air ambulance operators, asserting that the
FAA has been unable to keep pace with the industry’s rapid growth.³⁶ Those
expressing concern believe that the FAA has been lax in inspecting air ambulance
operations, particularly for new operators and operational bases, as well as at remote
base stations that are distant from company headquarters.³⁷ In terms of regulations,
critics also contend that the FAA has been slow to take action to better regulate safety
among air ambulance operators. The NTSB noted that while the FAA has taken a
positive step toward improving air ambulance safety by creating a task force in
August 2004 to look into helicopter air ambulance accidents, that task force had not
yet made any specific recommendations or proposals for regulatory change.³⁸ The
FAA has, however, issued special guidance to helicopter air ambulance operators and
has intensified efforts to review these operators’ training and procedures.

³⁵ Ira J. Blumen, M.D., and the University of Chicago Aeromedical Safety Committee, A
Safety Review and Risk Assessment in Air Medical Transport, 2002.
³⁶ Alan Levin and Robert Davis, “Surge in Crashes Scars Air Ambulance Industry.”
³⁷ Ibid.
³⁸ National Transportation Safety Board, Special Investigation Report on Emergency
Medical Service Operations.

Conducting Special Emphasis Inspections. In Fall 2005, the FAA
initiated a special emphasis inspection program targeting helicopter air ambulance
operators. The inspection program is designed to focus on policies, procedures,
training, communications, and management of flight operations and the development
of safety culture among operators with the goal of identifying and correcting factors³⁹
known to contribute to accidents among helicopter air ambulances. The FAA has
also issued a special bulletin for developing and critiquing air ambulance operator
training programs and operating procedures that are specifically designed to prevent
loss of control and CFIT accidents.⁴⁰ FAA inspectors will be looking for specific
improvements to pilot training to deal with inadvertent flight into low visibility
conditions, flight solely by reference to cockpit instruments, and recovery from⁴¹
unusual aircraft attitudes. Inspectors will also be looking at air ambulance operators
to see if they have implemented various procedures, such as pre-flight assessments
of obstacles and terrain considerations along the route of flight, and the use of
approved technologies to aid in-flight situation awareness in an effort to curtail
accidents.
Applying Consistent Regulatory Requirements During All Phases
of Operation. The NTSB also noted that when patients are not on board, for
example during positioning flights or en route to an accident scene, air ambulance
operators may operate under a less stringent set of regulations, because the FAA
regards medical personnel on board as essential crew members.⁴² When operating
under these less stringent regulations, air ambulance operators have no set minimum
requirements for in-flight visibility nor do any regulations pertaining to flight and
duty time for pilots apply. The NTSB found that, of the 55 air ambulance accidents
studied, 35 occurred while operating under these less stringent regulations without
patients on board. In 10 of these accidents, the flights were being conducted in
weather conditions that would not have met the minimum requirements for operation
under the more stringent set of commercial regulations required for flights with
patients on board. The NTSB concluded that, in its opinion, medical personnel on

³⁹ Federal Aviation Administration. Notice N8000.307: Special Emphasis Inspection
Program for Helicopter Emergency Medical Services. September 27, 2005.
⁴⁰ Federal Aviation Administration. Flight Standards Handbook Bulletin for Air
Transportation (HBAT) 06-02A: Helicopter Emergency Medical Services (HEMS) Loos of
Control (LOC) and Controlled Flight Into Terrain (CFIT) Accident Avoidance Programs.
Effective 1/23/2006, Revised 3/14/2006.
⁴¹ Aircraft attitude refers to its orientation relative to the horizon. Examples of unusual
attitudes include a steep bank, a dive, a steep climb, or some combination of these
conditions.
⁴² National Transportation Safety Board, Special Investigation Report on Emergency
Medical Service Operations. Note: Currently flights without patients may be operated under
regulations prescribed in Title 14 Code of Federal Regulations (CFR), Part 91, whereas
flights with patients on board must be operated under regulations contained in Title 14, CFR
Part 135. For the purposes of this discussion, the principal differences between these two
sets of regulations are that under Part 91, there are no flight and duty time limitations and
there are less stringent requirements regarding weather conditions that operators are
permitted to fly in.

board do not meet the definition of required crew members for flight operational
purposes, and therefore recommended that the FAA require air ambulance operators
to comply with more stringent commercial flight regulations whenever medical
personnel are on board, as they currently do when carrying patients.
The fact that air ambulance operations without patients are conducted under
separate regulatory guidelines also has a potential impact on those operations
conducted with patients on board. This is because without any specific duty time
regulations being applied to flights conducted without patients, such flights are not
counted in a pilot’s duty time totals. Therefore, lengthy flight operations without
patients on board could contribute to pilot fatigue and affect safety during subsequent
flights with patients on board. While regulations currently include industry specific
flight time and rest time requirements for helicopter air ambulance pilots,⁴³ flights
flown without patients are not required to be considered in complying with these
regulations. Therefore, notwithstanding the NTSB’s recommendation to conduct all
flights with medical personnel on board as commercial operations subject to specific
duty time limitations, policy makers may consider alternative approaches to account
for and limit pilot duty times in air ambulance operations in a manner that more
accurately reflects actual flight time logged, regardless of whether patients are on
board or not.
Addressing Concerns Over Pilot Fatigue. Addressing the specific issue
of pilot fatigue and duty time regulations among air ambulance operators is regarded
by many aviation safety experts as being very important because the combination of
stress, rotating shift work, and operating at or near the minimal flight crew staffing
levels needed to maintain 24/7 operations is common across the industry and⁴⁴
predisposes pilots to acute and chronic fatigue. While fatigue has not been
identified as a causal or contributing factor in very many air ambulance accidents,
this may largely be due to the difficulty in substantiating the presence of fatigue
following an accident. In 1988, the NTSB noted that, while pilot fatigue had only
been identified in one of the accidents it reviewed, pilot fatigue was suggested by
some in the EMS helicopter industry to be the primary cause of accidents.⁴⁵ Since
that time, because no notable changes have taken place with regard to regulations or
practices pertaining to pilot duty times across the industry, preventing pilot fatigue
would appear to still be a significant objective for improving safety in air ambulance
operations. Therefore, in addition to addressing the broader question of whether air
ambulance flights should adhere to commercial flight regulations during all phases
of a mission, including times when patients are not on board, policymakers may
consider possible changes in pilot duty time and flight time regulations to address
concerns over the potential role of fatigue in the safety of flight operations.
To fully address the issue of pilot fatigue, specific regulations pertaining to
flight time and rest requirements may need to be examined separately from the issue

⁴³ See Title 14, Code of Federal Regulations § 135.271.
⁴⁴ National Transportation Safety Board, Commercial Emergency Medical Service
Helicopter Operations.
⁴⁵ Ibid.

of requiring air ambulance operators to conform to other commercial operating
regulations. In particular, those regulations pertaining to weather minimums and
weather reporting requirements, when conducting flights with medical personnel on
board, may need to be examined as a separate issue. Specifically, air ambulance
operators have voiced concerns that applying existing commercial flight regulations
to patient pick-up flights may significantly limit the ability of air ambulances to
accept missions in reduced visibility. This, according to an industry trade group, is
due to the fact that commercial regulations, as currently written, require approved
weather reporting at the intended destination in order to fly solely by reference to
instruments.⁴⁶ This could significantly limit operators to visual flight conditions
only. Working around this issue may require specific exemptions or a separate set
of requirements for air ambulance operators. Although regulations and policies
pertaining to weather and flight duty time standards for air ambulance operations are
both important issues for consideration, uniformly applying commercial flight
regulations designed primarily for other purposes to all facets of air ambulance
operations may be an imperfect solution. Policy makers may consider tailoring these
regulations to the specific safety concerns and operational needs of the air ambulance
industry by dealing with those regulations pertaining to weather minimums and those
regulations pertaining to pilot duty times as distinct policy issues.
Increasing Maintenance Oversight. As previously mentioned, little
attention has been given to the oversight of maintenance practices at facilities that
maintain and repair air ambulance aircraft. However, consistent with this report’s
findings, an in-depth study of maintenance-related accidents found that about 23%
of helicopter air ambulance accidents may be attributed, in part, to mechanical or
maintenance issues. About one-third of these accidents were regarded as being the⁴⁷
result of inadequate or improper maintenance. Given that aviation safety experts
have devoted considerable attention to airline maintenance practices, the lack of any
specific focus on maintenance of air ambulance operations is somewhat surprising,
but this is likely attributable to the fact that these maintenance safety issues are
largely eclipsed by concerns over flight operational safety issues which account for
the large majority of air ambulance crashes. Nevertheless, policymakers may
consider whether additional oversight and scrutiny of air ambulance maintenance
practice may be able to provide additional insight into specific maintenance practices
that compromise safety and available options for preventing maintenance-related
incidents and accidents.
Improving Aircraft Crashworthiness. Aircraft crashworthiness and
accident survivability is another regulatory issue that hasn’t received much attention
with regard to air ambulance safety. A comprehensive examination of helicopter air
ambulance crash injuries and fatalities found that main cabin occupants of air
ambulance helicopters had about 4.5 times the risk of death or serious injury

⁴⁶ Graham Warwick. “Medical Alert.” Flight International, February 21-27, 2006, pp.

72–73.

⁴⁷ Based on data presented in Ira J. Blumen, M.D., and the University of Chicago
Aeromedical Safety Committee, A Safety Review and Risk Assessment in Air Medical
Transport, 2002.

compared to occupants of other helicopters.⁴⁸ The study concluded that the increased
risk is likely attributable to cabin design modifications to accommodate emergency
medical missions. The study went on to identify greater relative risks among lighter
weight air ambulance helicopters (i.e., helicopters weighing less than 4,500 pounds)
in crashes where there was a post-crash fire, among occupants not wearing shoulder
harnesses, and for mechanical-related crashes. For larger helicopters (i.e., helicopters
weighing more than 4,500 pounds), these distinctions between air ambulances and
other helicopters were not as noticeable. This finding could have important
implications if the service model for helicopter air ambulance operations continues
to shift toward more autonomous private operators who may be more likely to use
smaller, lighter-weight helicopters to keep aircraft acquisition and operating costs
low. The study concluded that the use of energy-absorbing seats that can handle
greater crash forces in combination with lap and double-shoulder (five-point)
harnesses, along with greater attention to crashworthiness in designing cabin
modifications for air ambulance operations could significantly improve occupant
survivability and reduce the severity of crash-related injuries. Based on an analysis
of military helicopter crash data, the study also concluded that the use of helmets by
flight crews and medical crews could significantly reduce the risk of serious and fatal
head injuries in a crash. Policymakers may consider whether specific design
guidance or standards for seats, seatbelts, and interior design modifications as well
as operational requirements for equipment such as shoulder harnesses and helmets
could reduce fatalities and mitigate injury risks in air ambulance crashes. Equipment
and design standards and requirements would likely have to strike a balance between
providing flight and medical crews with adequate protective measures while ensuring
that these safety measures do not unduly prevent or interfere with patient care and
other critical mission functions.
Implementing System Safety and Risk Management
Principles
The degree to which safety principles are trained and practiced as a matter of
routine within the air ambulance industry is a matter of considerable interest. While
the FAA and trade organizations within the industry have issued guidance to⁴⁹
operators to improve safety practices, available accident statistics suggest that these
safety measures either have not yet been adequately adopted and implemented across
the industry or have not been particularly effective. The principal trade organization
of air ambulance operators, the Association of Air Medical Services, recently
launched an initiative, called “Vision Zero”, with the goal of attaining an industry-
wide commitment to “...to reduce and eliminate errors of consequence—those events
within the transport medicine environment that result in serious injury or fatality –
and to reduce the entire spectrum of helicopter accidents by 80% over the next

⁴⁸ See also Ira J. Blumen, M.D., and the University of Chicago Aeromedical Safety
Committee, A Safety Review and Risk Assessment in Air Medical Transport, 2002.
⁴⁹ See, for example: AAMS, AAMS Brief – Part One: Our Commitment to Safety.”
Alexandria, VA: AAMS; AAMS, Air Medical Service Safety Initiative, Alexandria, VA:
AAMS; and Federal Aviation Administration, FAA Notice N8000.301: Operational Risk
Assessment Programs for Helicopter Emergency Medical Services.

decade.”⁵⁰ While these efforts suggest that the industry as a whole is concerned
about the current level of safety among air ambulance operators and desires to take
positive steps to improve safety, some, including the NTSB, argue that voluntary
measures to improve safety such as this are insufficient, and certain safety-related
changes such as formal dispatch procedures and risk management practices should
require mandatory, industry-wide compliance. Policymakers, either at the FAA or
in Congress, will ultimately have to weigh the merits of this argument and determine
whether the safety benefits of these initiatives outweigh the costs associated with
implementing them.
In its special study examining air ambulance accidents occurring between
January 2002 and January 2005, the NTSB found that a formal risk evaluation of the
mission may have prevented 13 of the 55 accidents reviewed.⁵¹ However, the NTSB
found that most operators have not implemented a formal risk evaluation process,
even though guidelines for setting up such a process has been made available by the
FAA. While the FAA has issued guidelines for implementing risk assessment
programs for helicopter air ambulance operations, this material is only advisory in
nature and is not required to be implemented.⁵² Therefore, the NTSB formally
recommended that the FAA require all air ambulance operators to develop and
implement flight risk evaluation programs and train all employees involved in
decision-making and support of flight operations on participating in these risk
evaluation processes.⁵³
In the airline industry, several initiatives to improve the collection and analysis
of safety-related operational data have taken root and are now common practice. For
example, air carrier flight operational quality assurance (FOQA) programs collect
extensive flight operational data. Using data mining techniques, operations that fall
outside the defined parameters of safe operations are identified and subsequently
investigated to determine the circumstances surrounding the incident, with the goal
of reducing or eliminating events that compromise safety and could lead to an
accident. Many airline safety programs also include internal reporting mechanisms
and specific “whistleblower” protections for employees that identify hazardous
operational practices. Mechanisms have been put in place at several airlines, through
a program called the Aviation Safety Action Program (ASAP), allowing employees
to voluntarily provide confidential reports regarding safety concerns to the FAA with
specific protections against negative consequences, except in those cases involving
suspected criminal actions or drug and alcohol misuse.⁵⁴ The objective of these
programs is to provide a mechanism for preemptively identifying and correcting
unsafe operations before they lead to an accident. While comprehensive FOQA and

⁵⁰ AAMS, “Vision Zero: The Time Is Now,” p. 1., AAMS, Alexandria, VA.
⁵¹ National Transportation Safety Board, Special Investigation Report on Emergency
Medical Service Operations.
⁵² See Federal Aviation Administration, FAA Notice N8000.301: Operational Risk
Assessment Programs for Helicopter Emergency Medical Services. August 1, 2005.
⁵³ National Transportation Safety Board, Special Investigation Report on Emergency
Medical Service Operations.
⁵⁴ See Title 49 USC, § 40123, and Title 14 Code of Federal Regulations, Part 193.

ASAP programs may be too complex to effectively implement in the air ambulance
industry, policymakers may consider whether similar approaches to information
sharing and safety data analysis regarding critical safety issues could be feasibly
implemented across the air ambulance industry.
Training and Procedures for Flight and Medical Crews
It has been reported that, in 2000, representatives from the air ambulance
industry approached the FAA with a proposal to require that air ambulance pilots and
crew members receive training in crew resource management (CRM). This type of
training is mandatory for airline crews and focuses on how to effectively
communicate risk information and use available resources to assess and manage
operational risks.⁵⁵ However, this proposal has not yet resulted in any FAA
recommendations or regulatory proposals. Presently, there are no specific training
requirement for pilots on topics such as CRM, risk management, and aeronautical
decision making beyond the general understanding of these topics required to obtain
commercial pilot certification and appropriate ratings required for employment, such
as helicopter and instrument ratings. These general requirements are considered
relatively minimal, and many safety experts argue that they do not receive adequate
coverage in general flight training and pilot testing. Moreover, training received on
these topics in the course of general flight training is not tailored to the specific
operational conditions and pressures that a pilot or crew member might experience
in air ambulance operations. Thus, any specific training in dealing with operational
risks unique to the flight environment of air ambulances is provided solely at the
discretion of the operator. While some operators provide this training in various
forms, there is no industry standard for course content or objectives for these types
of training programs.
In the NTSB’s 1988 study of helicopter air ambulance safety, it found that
among the 14 instrument-rated pilots involved in the crashes it examined, only one
was current to fly solely by instruments.⁵⁶ Similarly, a later analysis of pilot
qualifications among air ambulance operators concluded that, while a greater
percentage of air ambulance operators were instrument rated, a lack of instrument
currency or proficiency could be a detriment because instrument-rated pilots may
overestimate their instrument training skills and press on in deteriorating conditions,
despite not having adequate recent experience and practice with instrument flight
procedures.⁵⁷ Examining training practices in the medical helicopter industry, the
NTSB found a wide range of approaches to training, and noted that while many
operators had well-defined training programs on paper, actual training did not
adequately address real-world conditions in the operational environment. The NTSB
recommended supplemental training material on aeronautical decision making be
incorporated into initial and recurrent training for pilots. The NTSB also

⁵⁵ Alan Levin and Robert Davis, “Surge in Crashes Scars Air Ambulance Industry.”
⁵⁶ National Transportation Safety Board, Commercial Emergency Medical Service
Helicopter Operations.
⁵⁷ Ira J. Blumen, M.D., and the University of Chicago Aeromedical Safety Committee, A
Safety Review and Risk Assessment in Air Medical Transport, 2002.

recommended that guidelines for FAA inspectors be revised to include reviews and
approvals of initial and recurrent training for pilots to ensure that they provide
adequate levels of instruction on poor weather operations and accident scene
procedures.⁵⁸ The recently initiated FAA targeted inspection program for helicopter
air ambulance operators⁵⁹ appears to directly address these concerns, and therefore,
the effectiveness of ongoing FAA inspections of helicopter air ambulance operators
may be of particular interest as an issue for oversight of the FAA.
Besides flight crew training, there has also been a recent emphasis on providing
aviation-specific training to other members of the air ambulance team, principally
communications specialists that dispatch and monitor air ambulance flights. The
FAA has also suggested, but does not yet require, special training for ground
communications specialists that dispatch and track air ambulance flights covering
aviation weather, flight operations, and flight tracking procedures.⁶⁰ Unlike the
airlines, which must used FAA-certified dispatchers, air ambulance pilots are
typically dispatched by EMS dispatchers or communication specialists who typically
do not receive any formal training in aviation operations or aviation weather. The
NTSB has recommended that all air ambulance operators implement formal flight
dispatch procedures utilizing dedicated aviation dispatchers with formal aviation-
specific knowledge and experience that can assist pilots in assessing weather data,
provide comprehensive flight following, and aid pilots in making informed decisions
whether to accept or continue a mission.⁶¹ Policymakers will need to determine the
feasability of requiring dedicated flight dispatchers in the air ambulance environment,
and whether these services require an FAA certified dispatcher approved under
existing FAA training and certification requirements for flight dispatchers.
Alternatively, policymakers may evaluate whether mandatory training of existing
emergency medical communication specialists that work with or for air ambulance
operators on aviation-specific dispatch procedures, aviation weather, aircraft
capabilities, flight following, and so on, would meet the intent of this
recommendation. At least one company has already developed aviation-specific
training for emergency medical communication specialists conforming to FAA
recommended training for ground communication specialists and hopes that this form
of training will be mandated for the entire industry.⁶²

⁵⁸ National Transportation Safety Board, Commercial Emergency Medical Service
Helicopter Operations.
⁵⁹ Federal Aviation Administration. Flight Standards Handbook Bulletin for Air
Transportation (HBAT) 06-02A: Helicopter Emergency Medical Services (HEMS) Loss of
Control (LOC) and Controlled Flight Into Terrain (CFIT) Accident Avoidance Programs.
Effective 1/23/2006, Revised 3/14/2006.
⁶⁰ Ibid.
⁶¹ National Transportation Safety Board, Special Investigation Report on Emergency
Medical Service Operations.
⁶² “Air Dispatcher Training Should Make EMS Flights Safer.” Air Safety Week, April 24,

2006, p. 3.

Technology to Improve Safety in Low Visibility Conditions
Various technologies are available to improve visibility and pilot situation
awareness of terrain, obstacles, and weather. While these technologies may be of
benefit to improve the safety of air ambulance missions, some operators have
expressed concern over the cost of installing and maintaining these systems if doing
so was made mandatory as the NTSB has recommended. Others have questioned
whether these technologies are appropriately suited for air ambulance use, or whether
modifications may be needed to tailor these devices to the unique mission profiles
and needs of air ambulance operators, particularly for use on helicopter air
ambulance missions.
Terrain Warning Systems. The NTSB’s recent assessment of air ambulance
safety included a recommendation to equip all helicopters and aircraft used in
emergency medical services with terrain awareness and warning systems (TAWS,⁶³
previously referred to as enhanced ground proximity warning systems or EGPWS).
These devices provide pilots with visual displays and audible alerts for terrain
avoidance. Advanced Class A TAWS (TAWS-A) that rely on detailed terrain
databases, Global Positioning System (GPS) data or other means of precise aircraft
positioning, and radio altimeters to provide height above terrain information are
already required on all commercially operated aircraft with 10 or more passenger
seats. Slightly less sophisticated versions of TAWS, called Class B TAWS (TAWS-
B), which do not include radio altimeter height above terrain inputs, are required on
all turbojets and turboprops, whether commercially or privately operated, having six
or more passenger seats. A typical TAWS-B installation may cost between $10,000
and $30,000 per aircraft depending on existing equipment configurations. While
some larger fixed-wing air ambulance aircraft may already fall under the requirement
for TAWS-B installation if they have seating for six or more passengers, most
helicopter and airplanes used as air ambulances do not. The NTSB specifically
recommended that air ambulance operators install TAWS and provide adequate
training in the use of TAWS to their flight crews, although it did not specify whether⁶⁴
these aircraft should be equipped with TAWS-A or TAWS-B. The NTSB believes
that TAWS could help prevent many controlled flight into terrain or CFIT accidents,
which, as previously noted constituted one of the two most common causal factors
cited in air ambulance accidents.
Some operators have voiced concern, however, that false alarms generated by
the TAWS systems could distract pilots. These operators are worried that high false
alarm rates – particularly among helicopter air ambulances that frequently operate in
close proximity to terrain in a manner not typical of other aircraft and flight
operations – could largely negate any benefit that TAWS may provide in terms of
improving pilot situation awareness regarding terrain clearance. While false alarms
are a potential concern when using TAWS systems because they may distract pilots,
the NTSB and other aviation safety experts believe that the benefits of TAWS in
improving pilot situation awareness regarding the surround terrain far outweigh any

⁶³ National Transportation Safety Board, Special Investigation Report on Emergency
Medical Service Operations.
⁶⁴ Ibid.

negative effects that might occur due to false alarms. However, further operational
testing of TAWS usage in simulated air ambulance missions may be needed to fully
assess the suitability of TAWS in helicopter air ambulance operations.
Technologies to Enhance In-Flight Visibility. In addition to TAWS, a
variety of technologies are available to improve pilot situation awareness regarding
terrain and obstacles during low visibility conditions and at night. As shown in
Figure 2, nighttime visual conditions were a contributing factor in 14% and reduced
visibility due to weather was a factor in 9% of the helicopter air ambulance crashes
examined between 1991 and 2004. Technologies to improve visibility under these
restricted visibility conditions and at night could mitigate these types of accidents.
One broad category of available technologies to improve pilot vision, referred
to as night vision imaging systems (NVIS), rely on various forms of infrared sensors
or cameras to enhance a pilots view of the outside scene and avoid terrain and
obstructions at night. One example of NVIS technology is night vision goggles
NVGs), used extensively in military helicopter operations, which can be worn by
pilots to improve out-the-window visibility and aid in the avoidance of terrain and
obstacles, such as power lines. An FAA study found that properly used NVGs can
increase safety, enhance situation awareness, and reduce pilot workload during flights
at night.⁶⁵ Although the FAA has approved the use of NVGs and recommends they
be deployed for helicopter air ambulance operations, the NTSB found that most
operators do not use NVGs because they have only been recently made available for
non-military aviation use, equipping aircraft and training pilots is expensive, and they
can only be used effectively in sparsely populated areas where there isn’t much
ambient light. While the NTSB found that the use of night vision goggles may have
mitigated 13 of the 55 accidents it examined in its 2006 special study, it did not
formally recommend NVG usage, recognizing that these systems are not usable in
all situations.
Besides NVGs, other imaging systems are available for aviation use. Forward
looking infrared cameras (FLIR) can provide enhanced images of night and low
visibility scenes. FLIR images can be projected on screens in the cockpit or through
head-up displays (HUDs) that overlay the enhanced image on top of the out the
window scene. Recently certified enhanced vision systems (EVS) use similar
principles to present images generated from special infrared cameras in the cockpit,
usually on a HUD. EVS systems have been specifically certified by the FAA for use
in instrument flight operations for flying approaches to airports in poor visibility and
at night and several business and commercial jets have been equipped with this new
technology. Such systems could potentially be used to improve visibility and
situation awareness in air ambulance operations, especially for helicopter air
ambulance operations that fly into unprepared landing sites where navigational aids
and instrument approach procedures are not available to guide the pilot.

⁶⁵ W. T. Sampson, G. B. Simpson, and D. L. Green. Night Vision Goggles in Emergency
Medical Services (EMS) Helicopter. DOT/FAA/RD-94/21 (1994): Federal Aviation
Administration,

In addition to the aforementioned technologies that rely on cameras or sensors
to enhance vision by capturing information outside the spectrum of what is visible
to the human eye, the FAA has also approved synthetic vision systems (SVS) for
operational use. Unlike EVS, which relies on sensors or cameras to collect
information from the outside scene, SVS relies on precise positioning, principally
from very precise GPS receivers,⁶⁶ and accurate onboard terrain databases to present
pilots with a computer-generated image of the known terrain features and obstacles
in and around the aircraft’s flight path. These images can be overlaid on top of
navigational instruments, or like EVS, can be projected on a head-up display to
overlay on top of the out-the-window view. Coupled with highly accurate
positioning information, SVS can potentially provide helicopter air ambulance pilots
with accurate navigation and terrain avoidance capabilities in low visibility and night
conditions. As these technologies further advance, some combination of EVS and
SVS imaging may be able to provide air ambulance pilots with situation awareness
of terrain and obstacles that matches, or in some cases, surpasses visual capabilities
in unrestricted daylight conditions. Systems that combine EVS and SVS imaging are
currently in the testing and certification process and may provide a means to enhance
cockpit situation awareness in air ambulance operations in the near future.⁶⁷

⁶⁶ Presently, the greatest accuracy in positioning can be obtained from the use of GPS
augmented with Wide Area Augmentation System (WAAS) inputs that improve position
accuracy.
⁶⁷ Glenn Connor. “From Air to Ground.” Professional Pilot, April 2006, 54-60.