Abnormal and
Emergency Procedures
Chapter 13
Introduction
This chapter contains information on dealing with abnormal
and emergency situations that may occur in flight.
Aeronautical decision-making (ADM), a systematic approach
to determine the best course of action in response to a
given set of circumstances, should always be used rather
than making a quick decision without determining the best
outcome. Most emergencies can be prevented by making the
proper decisions. This may be the fi rst go/no-go decision of
whether to fl y, when to fl y, or where to fl y. All safe fl ights
start with proper prefl ight planning.
Figure 13-1. WSC aircraft coming down under a ballistic parachute
system.
Throughout this chapter, all abnormal and emergency
decisions should be based on ADM. Some situations allow
more time than others to evaluate the outcome. ADM
should be applied to any unplanned or unexpected situation
presented.
In addition to ADM, the key to any emergency situation,
and/or preventing a abnormal situation from progressing
to a true emergency is a thorough familiarity with, and
adherence to, the procedures developed by the manufacturer
and contained in the Aircraft Flight Manual and/or Pilot’s
Operating Handbook (AFM/POH). The following guidelines
are generic and not meant to replace the manufacturer’s
recommended procedures. Rather, they are meant to enhance
the pilot’s general knowledge in the area of abnormal and
emergency operations. If any of the guidance in this chapter
confl icts with the manufacturer’s recommended procedures
for a particular make and model weight-shift control (WSC)
aircraft, the manufacturer’s recommended procedures take
precedence.
Ballistic Parachute System (BPS)
The ballistic parachute system (BPS) provides an additional
safety margin to fl ying WSC aircraft. However, if utilized
when other alternatives would produce a better outcome or
if not deployed with the proper procedures, BPS system use
could create a worse situation than not using a BPS. The BPS
should be used only as a last alternative and only after other
options have been evaluated through ADM. [Figure 13-1]
The choice of adding a BPS as an additional system for
emergencies is up to the pilot. This decision should be made
by evaluating the disadvantages of an additional system, its
advantages, and the situations in which the system would
be utilized.
Advantages of a BPS:
• BPS can be used if there is a total loss of control of the
WSC. The term “loss of control” is key to when the
BPS should be deployed. Always fl y the aircraft fi rst,
but if the pilot cannot control or regain control of the
aircraft (loss of control), this is when the BPS should
be used. Loss of control might result from midair
collisions or wake tip vortices with other aircraft.
A loss of control could also result from structural
failure due to inadequate prefl ight or lack of proper
maintenance.
• BPS can be used if the engine quits and there are no
suitable landing areas. Although pilots try to have a
suitable landing area within gliding distance, there are
times when a parachute could be used with an engine
failure, such as over high trees.
• Pilot incapacitation is a situation where the BPS could
be used. This could be a pilot-in-command (PIC)
illness, such as a heart attack, or an external factor,
such as a bird strike in the face temporally blinding
the pilot. For example, if the pilot is incapacitated by
a bird strike, the pilot could feel for the handle and
pull it. Other designs allow the pilot and passenger
to be able to reach and actuate the BPS, while other
designs have two separate handles for the pilot and a
passenger. Many passengers feel safer if they know
they can actuate the BPS if the pilot is unable to fl y
the aircraft.
• Pilot disorientation with loss of control of the
aircraft is a situation where the BPS could be used.
In the unusual situation of severe vertigo or spatial
disorientation preventing the pilot from differentiating
up from down, such as severe turbulence, night fl ying,
or fl ying into bad weather, a BPS could be used.
Attempts should always be made to regain composure;
if attempts fail, then the BPS is an option.
Disadvantages of having BPS:
• It provides a false sense of security. A pilot might
believe that the BPS can save him or her from
hazardous situations, which could cause the pilot to
develop hazardous attitudes, exceed limitations, and
make bad decisions.
• Before impact, put hands in front of face and keep
arms and legs in and tight to body.
• After impact, exit aircraft immediately.
Emergency Landings
This section contains information on emergency landing
techniques in WSC aircraft. The guidelines that are presented
apply to the more adverse terrain conditions for which no
practical training is possible. The objective is to instill in the
pilot the knowledge that almost any terrain can be considered
suitable for a survivable crash landing if the pilot knows how
to slow and secure the WSC aircraft while using the WSC
structure for protection of the pilot and passenger.
Types of Emergency Landings
The different types of emergency landings are:
• Forced landing—an immediate landing, on or off an
airport, necessitated by the inability to continue further
fl ight. A typical example is an aircraft forced down
by engine failure.
• Precautionary landing—a premeditated landing, on
or off an airport, when further fl ight is possible but
inadvisable. Examples of conditions that may call for
a precautionary landing include deteriorating weather,
being lost, fuel shortage, and gradually developing
engine trouble.
• Ditching—a forced landing on water.
A precautionary landing is less hazardous than a forced
landing because the pilot has more time for terrain selection
and approach planning. In addition, the pilot can use power
to compensate for errors in judgment or technique. The
pilot should be aware that too many situations calling for a
precautionary landing are allowed to develop into immediate
forced landings when the pilot uses wishful thinking instead
of reason, especially when dealing with a self-infl icted
predicament. Trapped by weather or facing fuel exhaustion,
the pilot who does not give any thought to the feasibility
of a precautionary landing accepts an extremely hazardous
alternative.
Psychological Hazards
There are several factors that may interfere with a pilot’s
ability to act promptly and properly when faced with an
emergency. These factors include reluctance to accept the
emergency situation, the desire to save the aircraft, and undue
concern about getting hurt.
A pilot who allows the mind to become paralyzed at the
thought that the aircraft will be on the ground in a very short
time, regardless of the pilot’s actions or hopes, is severely
• The pilot could deploy the parachute when it is not
needed. A BPS should be utilized only as a last
alternative to normal emergency procedures. It should
not be used when ADM produces a better alternative
for the situation at hand.
• BPS systems installed on a WSC aircraft have greater
initial cost, maintenance, and weight.
• A BPS can be deployed accidentally. This can happen
when the actuation handle is not properly placed, or
when deployed by occupants not following appropriate
procedures.
• BPS systems may not fi re or could tangle during the
deployment. Like any system, it can fail or not be
operated properly, so there is no guarantee it will
fi re or deploy properly. However, if it is mounted,
maintained, and operated properly, the chances of a
successful deployment are good.
The BPS should not be used in abnormal or emergency
situations, such as engine failure when suitable landing areas
are within gliding distance. Other situations in which to avoid
using a BPS are during strong winds/convection/turbulence,
or if lost. Alternatives and greater detail is presented for these
situations where a BPS is not used later in this chapter .
Procedures for Using a BPS
In an emergency situation where ADM is used and the
best outcome for the given situation is the use of a BPS,
the following general procedure for properly operating the
BPS is:
• Select the proper location if still in control of the aircraft.
Consider wind drift and a descent rate of 900 to 1,800
feet per minute (fpm). A minimum 500 feet above
ground level (AGL) is recommended for complete
deployment that is low enough to provide accurate
targeting at intended area. (If below 500 feet AGL,
consider this a low deployment and skip this step.)
• Shut off the engine (this is especially important for
pusher WSC).
• Slow down and lift the wing on the side where the
chute will deploy (if a side deployment and above
500 feet AGL).
• Pull the BPS deployment handle hard and as far as
it will go. This can be more than 12 inches in some
situations.
• Hold the control bar firmly with bent arms until
parachute infl ates.
• Steer the descending WSC aircraft toward best landing
spot, if possible (some installations that hang from the
top at the hang point center of gravity (CG) may allow
some directional control).
Figure 13-2. Using vegetation to absorb energy.
handicapped. An unconscious desire to delay the dreaded
moment may lead to such errors as a delay in the selection
of the most suitable landing area within reach and indecision
in general. Desperate attempts to correct whatever went
wrong at the expense of aircraft control fall into the same
category.
The pilot who has been conditioned during training to
expect to fi nd a relatively safe landing area whenever the
fl ight instructor closes the throttle for a simulated forced
landing may ignore all basic rules of airmanship to avoid a
touchdown in terrain where aircraft damage is unavoidable.
Typical consequences are making a 180° turn back to the
runway when available altitude is insuffi cient, stretching the
glide without regard for minimum control speed in order to
reach a more appealing fi eld, or accepting an approach and
touchdown situation that leaves no margin for error. The
desire to save the aircraft, regardless of the risks involved,
may be infl uenced by two other factors: the pilot’s fi nancial
stake in the aircraft and the certainty that an undamaged
aircraft implies no bodily harm. There are times, however,
when a pilot should be more interested in sacrifi cing the
aircraft so that the occupants can safely walk away from it.
Fear is a vital part of the self-preservation mechanism.
However, when fear leads to panic, we invite that which we
want most to avoid. The survival records favor pilots who
maintain their composure and know how to apply the general
concepts and procedures that have been developed through
the years. The success of an emergency landing is as much
a matter of the mind as of skills.
Basic Safety Concepts
A pilot who is faced with an emergency landing in terrain
that makes extensive aircraft damage inevitable should
keep in mind that the avoidance of crash injuries is largely
a matter of:
1. Keeping vital structure (fl ight deck where the pilot
and passenger are seated) relatively intact by using
dispensable structure, such as wings, landing gear, and
carriage bottom to absorb the violence of the stopping
process before it affects the occupants.
2. Avoiding forward wing movement relative to the
carriage, allowing the mast to rotate into the fl ight deck
occupants, or the front tube to compress and break,
providing structure to impale/stab the occupants.
The advantage of sacrificing dispensable structure is
demonstrated daily on the highways. A head-on car impact
against a tree at 20 miles per hour (mph) is less hazardous for
a properly restrained driver than a similar impact against the
driver’s door. Statistics indicate that the extent of crushable
structure between the occupants and the principal point of
impact on the aircraft has a direct bearing on the severity of
the transmitted crash forces and, therefore, on survivability.
Compared to an airplane, the WSC aircraft has less structure
to absorb the impact and is moving slower, but the same
principles apply.
Avoiding forcible contact with the front tube, cowling,
dashboard, or outside structure is a matter of seat and body
security with the use of seatbelts. Unless the occupant
decelerates at the same rate as the surrounding structure, no
benefi t is realized from its relative intactness. The occupant
is brought to a stop violently in the form of a secondary
collision.
Dispensable aircraft structure is not the only available energy-
absorbing medium in an emergency situation. Vegetation,
trees, and even manmade structures may be used for this
purpose. Cultivated fi elds with dense crops, such as mature
corn and grain, are almost as effective in bringing an aircraft
to a stop with repairable damage as an emergency arresting
device on a runway. [Figure 13-2] Brush and small trees
provide considerable cushioning and braking effect without
destroying the aircraft. When dealing with natural and man-
made obstacles with greater strength than the dispensable
aircraft structure, the pilot must plan the touchdown in such
a manner that only nonessential structure is “used up” in the
principal slowing down process.
It should be noted that examples presented here are not to
Figure 13-3. Stopping distance vs. groundspeed.
2 G deceleration
42 feet
10.5 feet
Headwind
Tailwind
Groundspeed
25 mph
Groundspeed
50 mph
be practiced because these situations are hazardous and can
damage the WSC and injure occupants. These examples are
shown for informational purposes, in case similar situations
arise in the future.
The overall severity of a deceleration process is governed by
speed (groundspeed) and stopping distance. The most critical
of these is speed; doubling the groundspeed quadruples the
total destructive energy and vice versa. Even a small change
in groundspeed at touchdown, resulting from wind or pilot
technique, affects the outcome of a controlled crash. It is
important that the actual touchdown during an emergency
landing be made at the lowest possible controllable airspeed
using all available means.
Most pilots instinctively—and correctly—look for the largest
available fl at and open fi eld for an emergency landing.
Actually, very little stopping distance is required if the speed
can be dissipated uniformly; that is, if the deceleration forces
can be spread evenly over the available distance. This concept
is designed into the arresting gear on aircraft carriers, and
provides a nearly constant stopping force from the moment
of hookup.
For example, assuming a uniform 2 G deceleration while
landing into a headwind with a 25 mph groundspeed, the
stopping distance is about 10.5 feet; in a downwind landing
at 50 mph groundspeed, the required stopping distance is
42 feet—about four times as great. [Figure 13-3] Although
these fi gures are based on an ideal deceleration process,
it is interesting to note what can be accomplished in an
effectively used short stopping distance. Additionally,
landing uphill reduces the stopping distance and landing
downhill increases the stopping distance. Understanding
the need for a fi rm but uniform deceleration process in very
poor terrain enables the pilot to select touchdown conditions
that spread the breakup of dispensable structure over a short
distance, thereby reducing the peak deceleration of the fl ight
deck area. A careful consideration must be made considering
wind, slope, and terrain.
Attitude and Sink Rate Control
The most critical and often the most inexcusable error that
can be made in the planning and execution of an emergency
landing, even in ideal terrain, is the loss of initiative over
the aircraft’s attitude and sink rate at touchdown. When the
touchdown is made on fl at, open terrain, an excessive nose-
low pitch attitude brings the risk of “sticking” the nose in
the ground. Steep bank angles just before touchdown should
also be avoided, as they increase the stalling speed and the
likelihood of a wingtip strike.
Since the aircraft’s vertical component of velocity is
immediately reduced to zero upon ground contact, it must
be kept well under control. A fl at touchdown at a high sink
rate (well in excess of 500 feet per minute (fpm)) on a
hard surface can be injurious without destroying the fl ight
deck structure depending on the design of the airframe and
the shock absorbing system. On soft terrain, an excessive
sink rate may cause digging in of the nose wheel with the
wing and/or WSC aircraft rotating forward into the ground,
stopping with severe forward deceleration or tumbling with
higher speeds.
Figure 13-4. Increased altitude provides increased landing options.
Ground
1,000' AGL
500' AGL
2,000' AGL
5,000' AGL
5,000 Feet AGL 80 Square Miles
Terrain Selection
A pilot’s choice of emergency landing sites is governed by
the:
• Route selected during prefl ight planning and
• Height above the ground when the emergency
occurs.
The only time the pilot has a very limited choice is during low
and slow fl ying or during takeoff if the landing approach is
always within gliding distance of the runway.
It should be understood that the amount of area for available
landing sites increases at a rapid rate with increased altitude.
[Figure 13-4] As an example, a WSC aircraft with a 5 to 1
glide ratio fl ying at 500 feet AGL has 500 feet multiplied
by fi ve feet horizontal (or 2,500 feet) radius on the ground
to select a suitable landing area. For example, use a ½
mile radius. The area of available landing spots is π x r2,
approximately 0.8 square miles. At 1,000 feet AGL, this
area would be 3.1 square miles; at 2,000 feet AGL, this is
about 12.5 square miles; and at 5,000 AGL, this is almost
80 square miles.
Additionally, fl ying in a downwind direction provides more
area to be covered while fl ying upwind reduces the amount
of area that can be covered while looking for a suitable
landing area.
If beyond gliding distance of a suitable open area, the pilot
should judge the available terrain for its energy absorbing
capability. If the emergency starts at a considerable height
above the ground, the pilot should be more concerned about
fi rst selecting the desired general area than a specifi c spot.
Terrain appearances from altitude can be very misleading
and considerable altitude may be lost before the best spot can
be pinpointed. For this reason, the pilot should not hesitate
to discard the original plan for one that is clearly better.
However, as a general rule, the pilot should not change his
or her mind more than once.
Approach
When the pilot has time to maneuver, the planning of the
approach should be governed by three factors:
1. Wind direction and velocity
2. Dimensions and slope of the chosen fi eld
3. Obstacles in the fi nal approach path and the fi eld
itself
These three factors are seldom compatible. When compromises
must be made, the pilot should aim for a wind/obstacle/terrain
combination that permits a fi nal approach with some margin
for error in judgment or technique. A pilot who overestimates
the gliding range may be tempted to stretch the glide
Figure 13-5. Using treetops to “hang” the wing during an
emergency landing.
across obstacles in the approach path. For this reason, it is
sometimes better to plan the approach over an unobstructed
area regardless of wind direction. Experience shows that a
collision with obstacles at the end of a ground roll, or slide,
is much less hazardous than striking an obstacle at fl ying
speed before the touchdown point is reached.
Terrain Types
Since an emergency landing on suitable terrain resembles
a situation with which the pilot should be familiar through
training, only the more unusual situation is discussed.
Confi ned Areas
The natural preference to set the aircraft down on the ground
should not lead to the selection of an open spot between trees
or obstacles where the ground cannot be reached. Once the
intended touchdown point is reached, and the remaining open
and unobstructed space is very limited, it may be better to
force the aircraft down on the ground than to delay touchdown
until it stalls (settles). An aircraft decelerates faster after it is
on the ground than while airborne.
A river or creek can be an inviting alternative in otherwise
rugged terrain. The pilot should ensure that the water or creek
bed can be reached without snagging the wings. The same
concept applies to road landings with one additional reason
for caution: manmade obstacles on either side of a road may
not be visible until the fi nal portion of the approach.
When planning the approach across a road, it should be
remembered that most highways and even rural dirt roads
are paralleled by power or telephone lines. Only a sharp
lookout for the supporting structures or poles may provide
timely warning.
If the only possible landing alternative is a small clearing and
it is not possible to land the WSC aircraft, the BPS should
be deployed, if equipped, as discussed earlier.
Trees
Although a tree landing is not an attractive prospect, the
following general guidelines help to make the experience
survivable.
For example, if the trees are taller than 15 feet and not dense
enough to assure the wing could be set on top of them, use the
BPS if so equipped. This provides two possible chances of
hanging up in the trees and a slower descent rate if the WSC
aircraft does not become lodged in the trees and continues a
descent to the ground.
If the trees are estimated to be shorter than 15 feet or a BPS is
not installed on the WSC aircraft, landing in the trees should
be performed as follows:
• Keep the groundspeed low by heading into the
wind.
• Make contact at minimum indicated airspeed, but not
below stall speed, and “hang” the wing in the tree
branches in a nose-high landing attitude. Involving
the underside of the fuselage and both wings in the
initial tree contact provides a more even and positive
cushioning effect. Hold the control bar with both hands
more than shoulder width apart and bend elbows to
lessen the impact of the control bar against the chest.
[Figure 13-5]
• Avoid direct contact of the fuselage with heavy tree
trunks.
• Try to land in low, closely spaced trees with wide,
dense crowns (branches) close to the ground, which
are much better than tall trees with thin tops; the latter
allow too much free fall height. (A free fall from 75
feet results in an impact speed of about 40 knots or
about 4,000 fpm.)
• Ideally, initial tree contact should be symmetrical;
that is, both wings should meet equal resistance in the
tree branches. This distribution of the load helps to
maintain proper aircraft attitude. It may also preclude
the loss of one wing, which invariably leads to a more
rapid and less predictable descent to the ground.
• If heavy tree trunk contact is unavoidable once the
aircraft is on the ground, it is best to involve both
wings simultaneously by directing the aircraft between
two properly spaced trees. However, do not attempt
this maneuver while still airborne.
Water Landings ( Ditching)
Prefl ight planning for any fl ight where a water landing is
possible should include personal fl otation devices for the
pilot and occupants. A hook knife should also be accessible
for the pilot and passenger. A beach or landing spot where
an emergency landing can be made on land, is preferred
to landing in water. If a water landing must be made,
the aircraft should be positioned close to land in shallow
water, if possible, preferably four to fi ve feet deep to use
as a cushion but still deep enough to stand in with the head
above water.
With any altitude above the water, preparations should be
made to get rid of any items that would make it more diffi cult
to exit the WSC aircraft and swim once it enters the water.
This would include removing boots for swimming, discarding
any camera lanyards, headphones, or other unnecessary
items that could hinder the exit from the WSC aircraft once
underwater.
There are not many actual accounts of WSC aircraft ditching
in water, but all accounts at stalling above the water or fl ying
it in at minimum controlled airspeed stops the WSC aircraft
abruptly and puts the occupants under water immediately.
Depending on the speed, the WSC could tumble over the
water before stopping. Another account of a BPS deployment
provided a successful entry into the water. In any event,
the pilot and passenger would most likely be under water
immediately and disorientated. There are two alternate
techniques that have been successfully used for ditching in
the water:
• Flying to the water and stalling just above the
surface
• Using the BPS
Stalling Just Above the Water’s Surface
With a stronger wind, fl ying to the water and stalling just
above the surface is a viable alternative to landing in the
water. It has been done a number of times successfully. The
WSC aircraft should be fl own directly into the wind to slow
down the groundspeed as much as practical. Once the wheels
are close to the water surface just above minimum controlled
airspeed, abruptly push the control bar out to enter the water
at the slowest speed possible. Take a deep breath and hold it
before hitting the water.
Using the BPS
An alternate water landing technique is to use the BPS. This
should not be used in calm winds because the parachute
would come down over the WSC aircraft and the lines could
entangle the occupants during the escape. A slight breeze or
greater wind (some ripples on the water) is needed for this
technique so the parachute does not come down directly
onto the WSC aircraft. Use the BPS deployment technique
discussed earlier. Take a deep breath and hold it before
hitting the water.
Once Under Water in the WSC Aircraft
Once in the water, immediately release the seat belt, free
yourself and passenger of any restrictions, and swim to the
surface. If disoriented, swim toward light or follow bubbles
upward to the surface. The WSC will be sinking, so escape
must be made quickly. The control bar must be pushed
forward at all costs to release the pilot to exit the aircraft
and swim to the surface. The forces of the water could push
the control bar back and pin the front seat/pilot into the seat.
If the landing is in shallow water, the pressure pinning the
pilot into the seat may stop when the WSC aircraft sinks to
the bottom.
Emergency Equipment and Survival Gear
For any fl ight away from the airport, basic supplies should be
carried in case there is engine failure. At a minimum, supplies
should include a mobile phone/radio for retrieval, clothes
appropriate for the environment, ropes to tie down the WSC
aircraft, cash/valid credit cards, and food/water.
In the case of fl ying cross-country or over remote areas,
emergency equipment should be carried for a possible
extended period of being stranded. In addition to the basics
listed above, suplies for the appropriate time in the elements
should be carried. Survival gear for protection from the
elements should include clothing for hot and cold climates,
as applicable. Without proper clothing, someone can die
within hours from hypothermia or heat exhaustion. Water
is also very important for survival. Food is important, but a
person can survive over a week without it. Additional items
to include are a knife, signal mirror, extra portable radio and
batteries, emergency smoke/fl ares, and a large space blanket
doubling as tarp.
Other items specifi c to unique terrain and climate zone should
also be considered. For mountain terrain, a saw, shovel,
water purifi er, and 100-foot rope would be appropriate. For