out the U. S., and the pending issuance of a reg-
ulation requiring use of oxygen where cabin
altitudes exceed 12,000 feet (NPRM-67-30) are
remedial actions we have underway. Further
information is provided in FAA Report AM
66-28.

VI. Alcohol.

In spite of protests by various groups to
the contrary, ethyl alcohol continues to play a
significant role in U.S, general aviation acci-
dents. thy! alcohol produces euphoria, and
even in small amounts changes the mood and
judgment of individuals. In driving, a two-di-
mensional task, not involving roll and pitch pa-
rameters as is so with three-dimensional flight
(and involving neither stall speeds nor wind
drift), aleohol has been a concomitant for dec-
ades of homeward trips after evening cocktail
parties. In flight, even small amounts of alcohol
can incapacitate an airman from the judgment
standpoint. The toxicological evidence indicates
that a significant number of general aviation
pilots have attempted flights under circumstances
which exceed the pilot qualifications or the air-
craft limitations (instrumentation), resulting in
serious accidents.

Five years of toxicological data relative to
fatal general aviation accidents lend strong evi-
dence that alcohol continues to play an adverse
role in air safety. While some of these cases may
be “false” positives, due to putrefaction, contami-
nation, or other factors, many are substantiated
by a history of pilot consumption of alcohol im-
mediately prior to the fatal flight. In a number
of cases, unequivocal evidence that the alcohol
played a role in the accidents was not obtained,
hence, the official probable cause for these does
not reflect the presence of alcohol. On the other
hand, the data are firm enough in the aggregate
to warrant an aggressive safety education pro-
gram. The following data is instructive:

FAA Report AM 66-29 provides detailed in-
formation on this data.

VIL. Suicides (Volitional Acts).

Suicides encompass a certain percentage of
“accidents”, and in our view, since such delib-
erate acts are volitional, should not be cate-
gorized as accidents (the latter being “unplanned
events”). Several suicides occur each year
through the instrumentailty of an aircraft, pos-
sibly about a dozen in number. It is our feel-
ing that since suicides are not accidents, the
latter defined as unintended happenings, ac-
cident investigators should be alert in each in-
vestigation to clues suggesting a wilful act. If
the latter proves to be the case, perhaps suicides
should ‘be provided a separate category in
safety statistics, distinct from the accident data
which are accordingly reduced in magnitude. A
report on aviation suicides was made by the FAA
in Vol. 38, No. 10, Aerospace Medicine, October
1967, pp. 1058-1059.

VII. Aerial Application.

In July of 1965 a pilot lost control of his
Piper Supercub while spraying with insecticides
of the organophosphorous type. Laboratory
blood tests revealed that the cholinesterase level
was low enough to produce significant phys-
iologic impairment. It was felt by the inves-
tigators that in some way excessive exposure
to the insecticide was experienced by the pilot
during loading or handling procedures. The
FAA is continuing studies of the extent to which
toxic substances contribute to flight accidents
and has established a special laboratory activity
at the Civil Aeromedical Institute to receive
samples forwarded by investigators of agri-
cultural flying accidents. A concurrent safety
education program is underway. Report AM
66-30 gives a detailed analysis of aerial applica-
tion accidents.

1968 1964 1965 1966 1967*
‘Total Fatalities -. 900 980 1,020 1,123 1,016
Fatal Accidents ~-. ATT 510 543 564 508
Pilot Toxicology Performed 29% 42% 54% 62% T4h%
Pilot Positive Aleohol - 59(48%) — 82(39%) 105 (36%) 94(27%) 91(24%)
Less Than 50 mg% -. 19 23 45, 44 43,
50-99 mg% - 12 18 20 18 1
100-149 mg% 22 16 16 16
Over 150 mg% 19 19 24 16 21

*Data available as of February 1968.



these two groups as well as all airman. Motion
pictures illustrating the relationship of various
medical factors to accidents are being made by
the FAA. The latest of these is just completed
and describes the psychological factors which
underlie unsafe flight.

In conclusion, we recognize that many factors
conspire to cause accidents, and probably there

is an irreducible number of accidents which re-
sult from “unreachable” closed-minded. individ-
uals. We intend to continue our investigations
and research into the medical and emotional
factors underlying general aviation accidents
with the appropriate follow-up by educational
activities, including pamphlets, reports, talks to
pilot groups, and movies for loan.

REFERENCES

1, Bonn, Doveras, The Love and Fear of Flying, Inter-
national Universities Press, Inc., New York, 1953.
2, Rernnarpt, Roger F, "The Flyer who Fails: an

Adult Situational Reaction”, American Journal of

Psychiatry, 124:6, pp 740-744, December 1967.
8. Moynrman, Danrex P. (Chairman), Report of the
Secretary’s Advisory Committee on Trafic Safety,
Department of Health, Education, and Welfare, U. S.
Government, Washington, D. ©., February 29, 1968.
BEpeLL, RowLanp, H.S., “General Aviation Accident
Repeaters”, Presented at the Aerospace Medical As-
sociation meeting, Miami Beach, Florida, May 6-9,
1968.

»

5, Mouter, Stantey R., Bepett, Rowranp H. §&., Ross,
Avan, VerEcce, Evererr J., Aireraft Accidents by
Older Persons, OAM Report, No. 67-22, October 1967.

6, Verace, Evererr J., Type Airman Certification as Re-
lated to Accidents, OAM Report No. 67-23, October
1967.

. Monten, Stantey R., Recent Findings on the Im-
pairment of Airmanship by Alcohol, OAM Report, No.
66-29. September 1966.

8. Dittz, J.R. and Morris, E.W., Human Factors in

General Aviation Accidents, OAM Report No. 66-27,
July 1966.

a


continued educational program on the adverse ef-
fects emotions can have on flight behavior. The
use of an aircraft for expressing sexual frustra-
tions, the acute mental shock following marital
separation or divorce, and the use of dangerous
flight acts as a form of “self-punishment” rela-
tive to guilt feelings, are documented.*? The role
such dangerous maneuvers can play in creating
exhilaration as a counteractant to depressive feel-
ings represents a concomitant factor. The syner-
gizing effects of even a little amount of alcohol
with other factors so as to impair judgment and
mood has also been previously described. Such
factors have recently been implicated in aggres-
sive and dangerous automobile driving behavior
and should be reemphasized in a continuing avia-
tion safety program from which the evolving
new crops of pilots will benefit as well as those
old hands who may not have “gotten the mes-
sage.”° Office of Aviation Medicine FAA Re-
port AM 66-8 covers certain of these topics.

III. Weather.

Weather accidents, especially when they repre-
sent deliberate pentration of known adverse cir-
cumstances, constitute examples of wilful activity
which may be compared with “Russian Roulette”.
Our education activities are beamed at calling to
the attention of potential victims the hazards
of launching themselves into temporary atmo-
spheric extremes which hold promise of exceed-
ing the structural strength of their aircraft.
Freudian disciples have attributed a significant
number of these accidents to such factors as
“tempting the Gods”, thus suggesting inimor-
tality, pressing the weather to demonstrate mas-
culinity, and other psychic mechanisms. Since
the majority of general aviation weather acci-
dents occur after the pilot has had ample warn-
ing that a critical circumstance was developing
(either from the Weather Bureau, a Flight Serv-
ice Station or the obvious appearance of the ele-
ments), we are disseminating case history in-
formation so that airmen may be forewarned of
proclivities on the part of some to penetrate
known adverse weather.

IV. Carbon Monoxide.

No matter how often facts of carbon mon-
oxide poisoning have been disseminated, appar-
ently a certain percent of general aviation pilots

have failed to comprehend the significance of
this potential hazard. This past spring a pilot
highly experienced in flying could not account
for one hour of a two hour flight in his Piper
Apache while flying over Minnesota at night
after midnight. The pilot later recounted that
all three of the radios became inoperative and he
made a perfect gear-up landing at an airport.
When observers approached the aircraft, all of
the electrical equipment was on as the power
controls had not been turned off. The pilot was
in place mumbling incoherently over and over,
“so tired”. The radios, when tested, were in per-
fect condition. It developed that the gasoline
heater in the fuselage was in the “on” position,
the heater can had three one-inch cracks and the
exhause pipe from the heater was broken. The
investigators felt that carbon monoxide had es-
caped into the cabin and partially incapacited
the pilot. This near tragedy further emphasizes
our continuing efforts regarding the dissemina-
tion of information bearing upon the potential
hazards of carbon monoxide, with guidance as
to the periodic checks for defective heaters.

V. Hypoxia.

Hypoxia is a condition known to competent
airmen since World War I, yet, even today, gen-
eral aviation pilots climb to altitudes in excess
of twelve thousand feet for extended periods of
time and become impaired due to hypoxic
changes.

In February of 1967, a Cessna 401 obtained
an altitude of 23,000 feet over South Carolina
on an instrument flight plan while climbing to
25,000 feet. The aircraft was lost to air traffic
radar and a ground witness (a flight instructor)
heard a high pitched whine which was accele-
rating in nature followed by a dull thud. The
accident investigators found scattered debris and
evidence that the wings had separated in flight.
The evidence indicated that although the aircraft
was equipped with oxygen, the pilot had no ac-
cess to his oxygen mask (which was stowed in
the back out of reach). On some previous oc-
casions the pilot had boasted of having been
capable of operating at 25,000 feet without
oxygen.

Continued education of all pilots regarding the
adverse effects of hypoxia on performance, an ex-
panded physiological training program through-


IX. Appendicitis.

A May 1967 fatal Cessna 172 accident in Mon-
tana occurred when the pilot apparently got into
rising terrain in mountainous conditions and
could not climb out of a ravine. The post
mortem revealed that the pilot exhibited acute
suppurative appendicitis with periappendicitis
and abscess formation. The Regional Flight
Surgeon felt that the attempted gain of altitude
and concomintant gas expansion in the appendix
and abscess could have caused enough pain to
impair the pilot’s performance. Certainly the
presence of such a serious medical condition
in which wives or children with no, or minimum,
{recognizing that it may have been totally
asymptomatic) would potentially be adverse to
 pilot’s well being. We are continuously pub-
lishing Medical Facts for Pilots (in the Air-
mans’ Information Manual) and other medical
safety educational material and have prepared
several motion pictures for loan by the FAA to
pilot groups concerning the importance of phys-
ical state to safe flight.

X. Cardiovascular Disease.

Pilot inflight incapacitation due to experi-
encing a coronary occlusion or a cerebrovascular
accident occurs about six times each year as docu-
mented by the reports of the National Transpor-
tation Safety Board (formerly produced by the
Civil Aeronautics Board). Without doubt, were
it not for the physical standards regarding re-
petitive medical certification for airmen, the in-
flight incapacitation and accident rate would be
considerably higher. However, spectacular epi-
sodes continue to occur several times each year
flight ability, manage to land an aircraft after
cardiovascular incapacitation of the pilot. Con-
tinued educational programs aimed at identi-
fying for pilots the symptoms of cardiovascular
disease and the need for thorough physical ex-
aminations, together with the desirability of
physical fitness activities, are current preventive
measures of aviation medicine discussed and dis-
cussed in Aerospace Medicine, vol. 38, No. 10,
October 1967, pp. 1057-1059.

XI. Age.

Although age is considered significant in air
carrier operations (in the U. S. the retirement.
age for air carrier pilots is 60 years) no man-

datory upper limit is set for general aviation
pilots. The accident statistics relative to age in
general aviation flight activities bear out the
present philosophy. For example, the following
figures describe the accidents per 10,000 pilots
for the certificated and age categories shown:

16-29 80-44 45-59 60 & Total

years years years over Total
Student 60 94 11 82 7
Private 126 118 120 113 120
Commercial 254 146 109 123 152
Air Transport 298 118 59 104 93

Total

Accident Rate 106 6121-109 10S td

The above data reveal that the older pilots do
not experience a higher accident rate than their
younger colleagues. The table does not contain
“exposure” data such as the number of hours
flown per year, which may be less for pilots over
sixty. On the other hand, perhaps older pilots
are more cautious (thus achieving an older age)
and “expose” themselves to such things as adverse
weather or unwarranted low level maneuvers less
often. Detailed information is provided in FAA
Report AM 67-22.

XII.

The observation that some people are accident:
prone takes on real implications when the fol-
lowing statistics are viewed.* During the period
1965-66, a survey of 15,977 general aviation ac-
cidents revealed that 79 pilots experienced two or
more accidents. Six hundred and sixty had two
accidents, sixty-two had three and seven had
four. Dr. Bedell found that within the repeater
population, twelve percent were fatal (87 out of
729 repeaters). This segment of the airman pop-
ulation represents another area for safety educa-
tion activity.

Accident Repeaters.

XII. Physician Pilots.

Occupational studies relative to accidents have
revealed interesting statistics. For example, phy-
sician pilots in the U. S. appeared in the annual
fatal aircraft accident rosters an estimated four
times in excess of their representation within the
general aviation pilot population. After an in-
tensive educational program launched by the
FAA, the separate number of M.D. fatal acci-
dents dropped slightly, but not enough to give


AM 69-2

MEDICAL FACTORS IN U.S. GENERAL AVIATION
ACCIDENTS

P. V. Siegel, M.D.

S. R. Mohler, M.D.
Approved by Released by
°
S. R. Mouter, M.D. P. V. Srecet, M.D.
Cuter, AEROMEDICAL APPLICATIONS Frperan Arr SuRGEON

Drviston

January 1969

Department of Transportation

FEDERAL AVIATION ADMINISTRATION
Office of Aviation Medicine



a clear cut effect. The M.D. flight accident cir-
cumstances revealed that the majority of physi-
cian accidents resulted from fatigued M.D. pilots
undertaking long planned and highly anticipated
trips for recreational purposes. The victims hap-
pened to draw departure or return times which
coincided with adverse weather, and, in view of
the “therapeutic” nature of the flights, elected to
risk adverse weather rather than scrub the antici-
pated flight. When the above personal human
frailty pitfall was grought to the attention of the
pilots, some appear to have developed the capacity
to avoid future similar emergincies. Details are
given in FAA Report AM 66-25.

XIV. Gyrocopters.

In the United States a considerable home-built
amateur “experimental” movement is active and
tens of thousands of aircraft resulting from this
activity are in various stages of construction and
flying. The safety experience of the group ap-
pears quite good, and through their national or-
ganization, the Experimental Aircraft Associa-
tion, the dissemination of safety information is
quite extensive. In following the program, one
type, the separate small self-powered single seat
“gyrocopter” segment, seems to experience a rela-
tively high accident rate.

Selected examples of fatal accidents involving
powered gyrocopters are shown in Table I.
From the table, it is apparent that some en-
thusiasts are pursuing flight in the new gyro-
copters in a fashion reminiscent of the way early
aviators pursued flight in their fragile aircraft,
the result being a high accident rate due either
to pilot limitations or aircraft frailties. In view
of the popularity of this new segment of avia-
tion, we hope to encourage steps which effect a
reduction in gyrocopter accidents.

XV. Commentary and Conclusion.

Each year a new crop of student pilots emerges
and many move into the private pilot category.
From this, a significant number go on to higher
certification. Air safety information programs,
therefore, must be continuing and repetitive. Ac-
cident case histories are object lessons and the
dissemination of the factors leading to specific
accidents have important educational value for
all airmen, but especially the new airman. Of
critical significance are the Aviation Medical
Examiner (who is the only legally designated
individual periodically seen by each airman) and
the flight instructor (probably the most impor-
tant single person in the airman’s flight career).
Accordingly, our safety programs and literature
for distribution will continue to be directed to

Taste I

Date Location
9/25/66 Benton, Pennsylvania _—-.
10/22/66 Raleigh, North Carolina

10/26/66 North Kingsville, Ohio
12/12/66 Dowagiac, Michigan -.
1/28/67 Chino, California —

4/6/67 Scottsbluff, Nebraska -.
5/14/67 Westland, Michigan -.
7/10/67 El Mirage, California -
9/2/67 New Orleans, Louisiana -.
9/16/67 ~--_--------- Palmyra, New York —---~~---
10/10/67 -~----------- Cimarron Field, Oklahoma
10/22/67 -------.----- Lockport, Illinois --~.-----_-
11/5/67 Brown Field, San Diego -.

El Mirage Lake, California
Chula Vista, California
West Liberty, Iowa ~~.
Upshur County, West Va.

El Mirage, California ----.

West Point, Virginia --__--~~

Circumstances

Waiting details.

Waiting details.

Waiting details.

Waiting details.

Waiting details.

After owner started engine, propeller blades inflicted
fatal injury—strong surface winds.

Three descents then fatal, out of control, impact.

Waiting details.

Flying low over road, pulled up and nosed over, fol-
lowed by crash.

_-. On base leg, pieces came from gyrocopter at about

40 feet altitude.

_.. After circling airport at 100 feet, gyrocopter went

into a steep dive with rotor blades coming off in
air.

_-. Pilot carried “medi-alert” card referencing a pre-

vious heart attack.
while inflight.

Disintegrated at 200 feet.

Waiting details.

Waiting details.

Crashed near highway.

In strong winds, pilot thrown from aireraft, frac-
tured skull in blade contact.

Pilot may have had another

_.. Turned upside down shortly after take-off. Physi-

cian pilot.
Waiting details.



Qualified requesters may obtain Aviation Medical Reports from Defense Documentation
Center. The general public may purchase from Clearinghouse for Federal Scientific
and Technical Information, U.S. Dept. of Commerce, Springfield, Va. 22151


MEDICAL FACTORS IN U.S. GENERAL AVIATION ACCIDENTS

I. Introduction.

General aviation activity in the U. S. exceeds
that of any other country and presently involves
617,000 airmen and 115,000 active aircraft in a
total fleet of 150,000. Annual general aviation
flight hours are in the neighborhood of 21.3 mil-
lion as compared to 6 million for air carrier air-
craft, the latter numbering 2,150 of which about
1,700 are flying at any one time. Of the 617,000
airmen, seventy percent are student or private
pilots, twenty percent fly for hire, twenty percent
have instruments ratings and about 21,000 are air
carrier pilots and 18,000 are women, The FAA
fosters as high a level of general aviation safety
as practicable and in accomplishing this activity
attempts to thoroughly investigate all general
aviation accidents. In this latter role, the FAA
serves to assist the National Transportation
Safety Board which has the statutory respon-
sibility of determining the probable cause of civil
aircraft accidents.

The FAA, through its Accident Investigation
Branch within the Aeromedical Applications
Division, coordinates a broad program of med-
ical participation in general aviation accidents,
especially fatal accidents. This program is dis-
charged primarily through the seven Regions
under the activity of the respective Regional
Flight Surgeons, who, in turn, coordinate the
work the approximately six thousand designated
aviation medical examiners accomplish. When
autopsies are obtained following fatal accidents,
body fluids, and, or tissues, are analyzed by the
Armed Forces Institute of Pathology in Wash-
ington, D. C., the FAA’s Civil Aeromedical In-
stitute in Oklahoma City, or a qualified civil
pathology laboratory.

The increasing success of this medical pro-
gram can be seen in the fact that pilot autopsy
and toxicological investigations of fatal general
aviation accidents in the U. S. rose from 29% in
1963 to 74% in 1967.

The scope of the accident activity in the U. S.
is seen in the following data:

Total Accidents in

General Aviation
1966 1967
‘Total 5,786 6,281
Fatal Accidents 564 610
Fatalities 1,123 1,237
Airborne Collisons 28 26

Many of the above accidents result from cir-
cumstances having a medical basis and examples
of these types of accidents are described in the
following information.

II. Psychological Factors.

Emotions can result in the development of a
“head of pressure” which induces a pilot to un-
dertake hazardous activities (unwarranted low-
level manuvers).. For example, low level ma-
neuvers such as “buzz jobs” may be undertaken
as a result of such things as sexual frustration
relative to a girl friend, a wife, or a recently
divorced mate.

The very experienced pilot of a Stearman 75
made a series of low-level flight maneuvers over
a river in Hawaii, including a flight under a
bridge followed by an abrupt pull-up, in July of
1967. Afterwards he flew to a section of beach
and waved at a girl in a Bikini who waved
back. The pilot landed on the beach nearby, in-
troduced himself to the girl, then borrowed her
telephone, calling several bars to locate his girl
friend. While doing so he drank a beer. The
pilot then departed saying that if his newly met
acquaintance keeps wearing her Bikini, he was
coming back. He also said “Always think happy
thoughts”. On becoming airborne he executed
two loops near ground level, and on the second
loop impacted the ground with fatal conse-
quences. It developed that the pilot had recently
separated from his wife and in past years had
been known at times as a very heavy drinker.
The pilot had also told persons for some time
that he was going to fly under the bridge if it
were the last thing he ever did. The history
above is, in its general theme, repeated in other
sections of the U. S. often enough to warrant a