Weight-Shift Control Aircraft Flight

Inadvertent Flight into Instrument Meteorological Conditions (IMC)

Proper flight planning using available weather resources should allow a pilot to avoid flying when the probability of low visibility is high. It is expected that WSC pilots exercise good judgment and not attempt to fly when the visibility is questionable. However, this section is included as background for this emergency procedure for inadvertent flight into instrument meteorological conditions (IMC), flight without visual reference to the horizon.

Although it is possible to get an attitude indicator installed in a WSC aircraft, there are no training requirements for flying by instruments for sport or private pilot WSC ratings. Samples of these instruments are shown in Figures 13-9 and 13-10.

Sport pilots are not allowed to fly unless there is visual reference to the surface and three miles visibility. This is different for private pilots for whom there is not a requirement for visual reference to the ground and the minimum flight visibility is only one statute mile (SM).

Accident statistics show that the average airplane pilot who has not been trained in attitude instrument flying, or one whose instrument skills have eroded, will lose control of the aircraft in about 10 minutes once forced to rely solely on instrument reference. WSC pilots without any instrument training attempting to use instruments in IMC conditions would lose control much sooner. No WSC pilot should attempt flight into IMC conditions.

The purpose of this section is to provide guidance on practical emergency measures to maintain aircraft control in the event a VFR pilot encounters IMC conditions. The main goal is not instrument flying; it is to help the VFR pilot keep the aircraft under adequate control until suitable visual references are regained.

The first steps necessary for surviving an encounter with IMC by a VFR pilot are:

• Recognition and acceptance of the gravity of the situation and the need for immediate remedial action.
• Maintaining control of the aircraft.
• Obtaining the appropriate assistance in getting the aircraft out of IMC conditions.

Recognition

A VFR pilot is in IMC conditions anytime he or she is unable to maintain aircraft attitude control by visual reference to the natural horizon, regardless of the circumstances or the prevailing weather conditions. Additionally, the VFR pilot is in IMC any time he or she is inadvertently or intentionally and for an indeterminate period of time unable to navigate or establish geographical position by visual reference to landmarks on the surface. These situations must be accepted by the pilot involved as a genuine emergency requiring immediate action.

As discussed earlier, when entering conditions in which visibility is decreasing or IMC, the pilot should turn around, climb, or descend immediately and return to where ground visibility is known. Do not continue assuming that conditions will clear and visibility will be regained.

Maintaining Aircraft Control

Once the pilot recognizes and accepts the situation, he or she must understand that the only way to control the aircraft safely is by using and trusting the flight instruments. Attempts to control the aircraft partially by reference to flight instruments while searching outside the flight deck for visual confirmation of the information provided by those instruments results in inadequate aircraft control. This may be followed by spatial disorientation and complete loss of control.

The most important point to be stressed is that the pilot must not panic. Recognize the situation and take immediate action. The task at hand may seem overwhelming, and the situation may be compounded by extreme apprehension. The pilot must make a conscious effort to relax and understand that the only concern at this point is to fly toward known visibility. If climbing into a cloud, reduce throttle and descend. If descending into a cloud, increase throttle and climb out of the cloud. If visibility is suddenly lost (e.g. flying into a cloud), turn 180° and fly toward known visibility.

The pilot should remember that a person cannot feel control pressures with a tight grip on the controls. Relaxing and learning to control with the eyes and the brain instead of muscles usually takes considerable conscious effort.

The pilot must believe that the flight instruments show the aircraft’s pitch attitude and direction regardless of what the natural senses tell. The vestibular sense (motion sensing by the inner ear) can confuse the pilot. Because of inertia, the sensory areas of the inner ear cannot detect slight changes in aircraft attitude nor can they accurately sense attitude changes which occur at a uniform rate over a period of time. On the other hand, false sensations are often generated, leading the pilot to believe the pitch attitude or direction attitude of the aircraft has changed when, in fact, it has not. These false sensations result in the pilot experiencing spatial disorientation.

Attitude Control

Attitude is defined as “The position of an aircraft as determined by the relationship of its axes and a reference, usually the earth’s horizon.” For WSC, the pitch and the roll are the relevant attitudes.

Most aircraft are generally, by design, inherently stable platforms and, except in turbulent air, maintain approximately straight-and-level flight if properly trimmed and left alone. They are designed to maintain a state of equilibrium in pitch, roll, and yaw. The pilot must be aware, however, that a change about one axis affects the other axes. The WSC aircraft is stable in the yaw and pitch axes, but less stable in the roll axis. The yaw and pitch axes of the WSC are easy to control, but the roll axis is the challenge for WSC aircraft control in IMC. The key to emergency aircraft attitude and directional control, therefore, is to:

• Fly at the normal trim speed. To climb, increase throttle; to descend, decrease throttle. To fly level, fly at the throttle setting that provides level flight. The vertical speed indicator or altimeter provides information regarding pitch attitude.
• Resist the tendency to overcontrol the aircraft. Fly with fingertip control. No attitude changes should be made unless the flight instruments indicate a definite need for a change.
• Make all attitude changes smooth and small, yet with positive pressure.

The primary instrument for roll control is the attitude indicator if so equipped. [Figures 13-9 and 13-10]

For aircraft not equipped with an attitude indicator, a magnetic compass [Figure 13-11]

or a GPS [Figure 13-12]

are the instruments that can be used for roll control. The compass stays stationary and the WSC aircraft rotates around the compass dial. A pilot is flying wings level if the compass heading is not changing. If the compass is changing direction, the aircraft is banked into a turn. Similarly, the GPS provides ground track. If flying wings level, the GPS ground track is steady. If the GPS ground track is changing, the aircraft is in a bank and turning.

Turns

Turns are perhaps the most potentially dangerous maneuver for the untrained instrument pilot for two reasons: 

• The normal tendency of the pilot to overcontrol, leading to steep banks.
• The inability of the pilot to cope with the instability resulting from the turn.

As an example, a 180° turn would be the most likely turn to exit a cloud and return to where there is visibility with the surface. The direction the turn started should be noted in order to determine the direction needed to exit the IMC conditions. For example, if heading North when flying into the cloud, turn 180° and head South to exit the cloud.

When a turn must be made, the pilot should anticipate and cope with the relative instability of the roll axis. The smallest practical bank angle should be used—in any case no more than 10° bank angle. [Figure 13-13]

A shallow bank takes very little vertical lift from the wings, resulting in little if any deviation in altitude, and the WSC aircraft can continue to be fl own at trim speed. It may be helpful to turn 90° and then reduce the bank and return to level flight. This process may relieve the progressive overbanking that often results from prolonged turns. Repeat the process twice until heading in the opposite direction of entry in order to exit. Once on the proper heading to exit the IMC conditions, maintain this heading until obtaining visual reference with the surface.

Turns with a magnetic compass or a GPS would be similar but the only indication of bank angle is the rate at which the compass or GPS is rotating. The rotation should be slow and steady and not increase in speed. Any increase in compass or GPS rotation should be slowed by decreasing the bank back to level flight to avoid increasing the bank. Practicing gentle turns and observing the rotational speed of the compass and GPS under VFR conditions will help a pilot recognize an acceptable rotational speed flying at trim speed should need ever arise.

High Winds and Strong Turbulence

Preflight planning for intended airports and winds aloft over the planned route and possible diversions can provide the pilot a means of anticipating the winds that would exceed aircraft or pilot capabilities. However, unanticipated high winds can create an emergency for any aircraft. High winds during cruise flight are not a danger unless they create extreme/severe turbulence, or the pilot is flying with questionable fuel reserves into a headwind that is stronger than expected.

High Winds and Turbulence During Cruise Flight

If the winds at cruise altitude provide an unanticipated slower groundspeed than planned, and the fuel reserves are questionable, the flight should be diverted to an alternate airport so there is no chance of running out of fuel for the intended flight. Stronger headwinds and crosswinds slow the groundspeed; tailwinds increase the groundspeed, resulting in the ability to reach airports that are farther away. The GPS is an accurate tool for measuring an aircraft’s groundspeed during flight.

In high winds, it is generally advisable to cruise with enough ground clearance to assure that turbulence or sinking air does not reduce altitude to an unsafe level. For example, maintain at least 1,000 feet AGL when flying in strong winds to be far enough away from the ground to account for any turbulence, wind shear, or downdrafts. If a pilot is flying and sees high wind or a gust front approaching with blowing dust or other indicators, a decision must be made to land and secure the WSC aircraft before the gust front hits, or turn and fly away from the area as fast as possible. Never fly into a gust front. If it looks like strong winds, it probably is and avoiding it is wise.

Strong turbulence can be created from high winds, wind shear, rising/falling unstable air, or any combination of these. As described in the basic flight maneuvers chapter, the pilot should keep the wings and pitch angle within the manufacturer’s limitations through power and control bar flying techniques. Generally, if the turbulence continues to increase, fly back to where the turbulence was less severe instead of continuing where the turbulence might become more severe. However, if the pitch becomes too high and a whip stall occurs, as the nose drops into a dive, the pilot should push the control bar full forward and apply full power for the best chance of recovering to normal flight and not progressing into a tumble. The best whip stall/tumble avoidance is to avoid severe turbulence and keeping the nose within the manufacturer’s limitations.

High Winds and Turbulence During Takeoffs and Landings

Takeoffs in high winds can simply be avoided by deciding not to fly. However, if a pilot takes off and encounters high winds or turbulence, high energy should be maintained throughout the climb and departure.

If it is determined that the winds are too high for landing at the intended location, divert to another location or wait until the strong winds subside to land. This is where the Automated Weather Observation Station (AWOS), Automated Surface Observing System (ASOS), or radio contact with other airports can assist the pilot in finding an airport with wind conditions within the pilot’s capabilities and aircraft limitations.

If the headwind is within the pilot’s capabilities and aircraft limitations but the crosswinds are above any limitations, the pilot may need to land on a taxiway or sideways on a runway that is wide enough, thus reducing the crosswind component to acceptable levels. Strong winds produce strong mechanical turbulence on the lee side of objects which should be considered and avoided during any takeoff or landing in strong winds.

High Winds During Taxi

For strong head winds during taxi, the nose must be lowered to keep the WSC aircraft on the ground. Raising the nose could allow the WSC aircraft to lift off. In any case, the nose should be lowered completely to keep the WSC aircraft on the ground. In strong tail winds, the nose must be raised so that the wind does not get underneath the wing and lift it up from the back and possibly tumble it forward. If the wing starts to lift from the back, release the brake and push the control bar forward to keep the wing from lifting and possibly tumbling forward.

Strong crosswinds during taxi must be managed by keeping the wing level or slightly down into the wind so the wind does not catch it, lift up, and topple the WSC aircraft to the side, causing significant damage. If the wind pushes down on the wing, it could pin it to the ground which is the better option. If the wing does become pinned from the wind, the pilot can give some throttle and steer into the wind, rotating around the tip and freeing the wing from the pinned state. This may cause damage to the tip from scraping on the ground. If the windward side gets too high and wind gets under the wing lifting it from the side, all efforts should be made to hold it down while the front wheel is turned downwind and the nose raised to turn with the wind and avoid tumbling sideways.

Taxiing to a location that is on the leeward side of a structure into the wind shadow provides the best option for exiting the WSC aircraft in high winds. When available, seek assistance to exit and/or secure the WSC. If no wind shadow is available, the pilot can turn the WSC aircraft into crosswind and pin the wing to exit.

Electrical System

The loss of electrical power can deprive the pilot of communications and navigation systems, but for day/VFR conditions this is not a life threatening situation because most engines ignition systems are on a separate electrical system and not dependent on the battery for keeping the engine running. However, losing communications does present some challenges especially if operating at a controlled tower airport in which procedures in the Airman’s Information Manual (AIM) would be followed.

Pitot-Static System

The source of the pressure for operating the airspeed indicator, the vertical speed indicator, and the altimeter is the pitot-static system. Most WSC aircraft have pressure for the airspeed indicator. If this becomes plugged, the airspeed indicator may not read properly. If it is suspected that the airspeed indicator is not reading properly, use the feel of the aircraft and the trim position to determine speed. It is perfectly safe to fly a WSC aircraft without an airspeed indicator if the pilot has developed a feel of the aircraft since the trim position speed is known and all other speeds can be determined based on the feel of the air and the pressure on the control bar.

Altitude and vertical speed utilize static pressure. Because there is typically no static line connecting these, they operate independently. Therefore, if one fails or becomes plugged, the other can act as a reference. For example, if the altimeter fails for any reason, the vertical speed indicator would provide the pilot with information on whether the aircraft was climbing, level, or descending. The global positioning system (GPS) (if equipped) could also provide altitude readings. If the vertical speed indicator failed, the altimeter could provide information on whether the aircraft was climbing, level, or descending by looking at the altitude reading over time.

Landing Gear Malfunction

If there is any landing gear malfunction before or during takeoff, the flight or takeoff should be aborted and the malfunction fixed before attempting another takeoff. However, if a malfunction takes place during or after takeoff in which the landing gear is not completely functional for landing, the situation should be evaluated using aeronautical decision-making (ADM) to make the best choice based on the outcome of the situation.

If a tire falls off, a known flat of the tire is evident, or a landing gear strut has shaken loose or become damaged, precautionary measures must be taken to minimize the results from landing with a defective landing gear.

Fly to a smooth runway where the WSC aircraft can skid and not stop abruptly and tumble. Inform the local ATC, UNICOM, or multicom frequency that there is a MAYDAY in order to obtain immediate help for a crash landing. There is no hurry to land, so use ADM to survey the situation and make the best decision on where and how to land. Find a location that has medical support, a smooth runway that minimizes abrupt stops/tumbling, and land into the wind for the best outcome. Attempt to make a normal approach into the wind with the lowest possible speed to touchdown.

Inadvertant Propeller Strike

A propeller strike in a pusher WSC aircraft is more dangerous than in any other aircraft. If an object or the propeller is flung up into the wing trailing edge, a structural failure could occur. This situation should not be underestimated or ignored. Procedures should be implemented and followed to avoid propeller strikes from articles flying out of the flight deck. Passengers sitting in the back are the greatest risk to propeller strikes. A comprehensive preflight brief with proper flight deck management procedures should reveal any open pockets or items that could dislodge and fly into the propeller. The passenger in the back should be instructed not to take off gloves, helmet, or glasses, or pull out a camera/mobile phone without a lanyard. However, the passenger in the rear seat cannot be monitored completely; it is possible that items could fly out of the flight deck and go through the propeller, presenting a serious situation.

If a bird strike occurs or anything else hits the propeller, reduce throttle immediately and evaluate the situation. The severity of the vibration is the key element to determining what to do. If the vibration is severe, shut off the engine and make an emergency landing. Minor vibration can be tolerated, but the risk of flying with a damaged propeller, which could dislodge and hit the sail, should be minimized. It is best to shut down the engine and perform an emergency landing.

Stuck or Runaway Throttle

Throttles can stick above idle or unexpectedly increase, which is called a runaway throttle. If on the ground, a runaway throttle can be disastrous if not anticipated and mitigated. A pilot (and instructor, if teaching) should always have access to the ignition system in order to shut it off immediately in the event of a throttle stuck above idle or a runaway throttle. A runaway throttle can be caused by the pilot or student pushing on the throttle pedal during taxi or startup, thinking it is the right brake, as in an airplane. Setting the cruise throttle to full open rather than full closed during startup also causes a runaway throttle. On startup, the checklists must be followed, including cruise throttle closed, foot off of foot throttle, brake on, propeller cleared, etc. The PIC must have control of the ignition to shut it off immediately during startup and taxi. A runaway or stuck throttle during flight can be handled by climbing or flying to a suitable location where the engine can be shut off and a safe engine-off landing can be made.

Abnormal Engine Instrument Indications

The AFM/POH for the specific aircraft contains information that should be followed in the event of any abnormal engine instrument indications. The table in Figure 13-8 offers generic information on some of the more commonly experienced inflight abnormal engine instrument indications, their possible causes, and corrective actions.

It is important to know that when an engine temperature probe fails, it usually reads an unusually low value, zero, or does not register. This should be taken into account when evaluating the situation with engine instruments.

Recovery from a Steep-banked Spiral Dive

At times, weight-shift control pilots find themselves in an unintentional steep-banked descending spiral turn. This may happen while performing an emergency descent but more commonly happens when the pilot spots something on the ground and wants to get a closer look. The pilot initiates a turn which steepens to 45 to 60 degrees of bank or greater. Through turbulence, wind gusts, or inattention the turn may develop into a steep-banked spiraling descent. If the pilot attempts to arrest the descent by pushing out the control bar and increasing pitch, the rate of turn and rate of descent will increase and an accelerated stall may ensue. It may require significant force to level the wing at this point and with some wings it may actually be impossible unless the correct technique is followed. If the maneuver began at low altitude, there will be very little time to correct the situation before a crash occurs. The appropriate recovery technique is to simultaneously reduce throttle, pull the control bar in to reduce pitch, and move the control bar to the side to level the wing. Pulling the control bar in to reduce pitch may seem contrary to a pilot’s instinct when the ground is rushing up, but it must be done to unload the wing and reduce control forces sufficiently to allow the pilot to level the wing. Once the wings are leveled, the pilot should be careful not to stall the wing or build up excessive speed to accomplish a successful dive recovery.

Practicing recovery from a steep spiral should only be performed after receiving instruction from an experienced and properly certificated flight instructor. The purpose of practicing this maneuver is to build recognition of and a reflexive response to a steep-banked spiraling dive. Start all practice at an altitude that will permit a recovery at no lower than 1,000 feet above the ground. An altitude of at least 2,500 AGL is recommended. Before starting the maneuver, the pilot should ensure that the area is clear of other traffic. Begin with a steep turn in level flight with adequate power to maintain altitude and at a speed well above the stall speed for the planned bank angle. The bank angle should be at least 45 degrees and below the manufacturer’s maximum bank limitation. Allow the aircraft to begin a slow descent with a slight reduction in power, but be careful not to exceed the manufacturer’s airspeed limitations. It may be necessary to push the control bar out somewhat as part of establishing the spiral and to control speed. Once the steep spiral is established the pilot may notice that the control forces required to level the wing or counter the wing’s overbanking tendency will have increased. Do not push the control bar further out as it will likely result in an accelerated stall. Recovery should be initiated rapidly by simultaneously reducing the throttle to idle, pulling in the control bar, and reducing the bank angle to zero. A recovery must be performed by carefully controlling pitch and G-forces as the aircraft will naturally pitch up once the wings are level. As the airspeed returns to a normal cruise speed increase the throttle to maintain level flight. The pilot must be careful not to stall the aircraft or exceed airspeed limitations at all times.

The following are some errors that are commonly made during the recovery of a steep spiral:

• Failure to adequately clear the area. 
• Entering the maneuver at a speed inadequate to prevent a stall at the selected bank angle. 
• Allowing the airspeed to build rapidly without beginning a recovery. 
• Leveling the wing without pulling the bar in and reducing throttle. 
• Excessive pitch-up attitude during the recovery. 
• Stalling the wing anytime during the maneuver. 
• Failure to scan for other traffic before and during the maneuver.

Emergency Descents

An emergency descent is a maneuver for descending as rapidly as possible to a lower altitude or to the ground for an emergency landing. The need for this maneuver may result from an uncontrollable fire, avoidance of other aircraft, weather, or any other situation demanding an immediate and rapid descent. The objective is to descend the aircraft as quickly as possible within the structural limitations of the aircraft. Simulated emergency descents should be made in a turn to check for other air traffic below and to look around for a possible emergency landing area. A radio call announcing descent intentions may be appropriate to alert other aircraft in the area. When initiating the descent, a bank angle of approximately 45° to 60° should be established to maintain positive load factors (“G” forces) on the aircraft. Generally, the steeper the bank angle is, the quicker the descent is. But caution should be exercised with steep bank angles for extended periods because the high G forces and rotation can cause disorientation or motion sickness, which might make matters worse. The manufacturer’s bank and speed limitations should not be exceeded.

Emergency descent training should be performed as recommended by the manufacturer, including the configuration and airspeeds. The power should be reduced to idle. The pilot should never allow the aircraft’s airspeed to surpass the never-exceed speed (V_NE) or go above the maximum maneuvering (V_A) speed, as applicable. In the case of an engine fire, a high airspeed descent could extinguish the fire. The descent should be made at the maximum allowable bank angle and airspeed consistent with the procedure used. This provides increased loads and drag and therefore the loss of altitude as quickly as possible. The recovery from an emergency descent should be initiated at an altitude high enough to ensure a safe recovery back to level flight or a precautionary landing.

When the descent procedure is established and stabilized during training and practice, the descent should be terminated. For longer descents, alternating turn directions should be used so the pilot does not become disorientated. Prolonged practice of emergency descents should be avoided to prevent excessive cooling of the engine cylinders. [Figure 13-7]

Inflight Fire

A fire in flight demands immediate and decisive action. The pilot must be familiar with the procedures to meet this emergency as contained in the AFM/POH for the particular aircraft. For the purposes of this handbook, inflight fires are classified as: engine fires and electrical fires. If a fire extinguisher is installed on the WSC aircraft, the passenger should be briefed on its use and the pin should be connected to the extinguisher by a lanyard so it cannot be dropped into the propeller, creating a worse situation.

Engine Fire

An inflight engine fire is usually caused by a failure that allows a flammable substance such as fuel, oil, or hydraulic fluid to come in contact with a hot surface. This may be caused by a mechanical failure of the engine itself, an engine-driven accessory, a defective induction or exhaust system, or a broken line. Engine fires may also result from maintenance errors, such as improperly installed/fastened lines and/or fittings, resulting in leaks.

Engine fires can be indicated by smoke and/or flames coming from the engine area. They can also be indicated by discoloration, bubbling, and/or melting of the engine cowling skin in cases where flames and/or smoke are not visible to the pilot. By the time a pilot becomes aware of an inflight engine fire, it usually is well developed. Unless the aircraft manufacturer directs otherwise in the AFM/POH, the first step after discovering a fire is to shut off the fuel supply to the engine (if so equipped). The ignition switch should be left on in order to use up the fuel that remains in the fuel lines and components between the fuel selector/shutoff valve and the engine (if equipped with an electric fuel pump). This procedure may starve the fire of fuel and cause the fire to die naturally. If the flames are snuffed out, no attempt should be made to restart the engine.

If the engine fire is oil-fed, the smoke is thick and black, as opposed to a fuel-fed fire which produces bright flames with less smoke.

Some light aircraft emergency checklists direct the pilot to shut off the electrical master switch. However, the pilot should consider that unless the fire is electrical in nature, or a crash landing is imminent, deactivating the electrical system prevents the use of radios for transmitting distress messages and also causes air traffic control (ATC) to lose transponder returns.

The pilot must be familiar with the aircraft’s emergency descent procedures and remember that:

• An engine fire on a WSC aircraft means the flames are going to the rear of the aircraft where minimum components are exposed. If the BPS is used, it would change the direction of the flames, possibly setting the wing and/or fuselage on fire. The flames could also burn the parachute line, creating worse problems. 
• The aircraft may be structurally damaged to the point that its controllability could be lost at any moment. 
• The aircraft may still be on fire and susceptible to explosion. 
• The aircraft is expendable—the only thing that matters is the safety of those on board.

Electrical Fires

The initial indication of an electrical fire is usually a slight amount of smoke and the distinct odor of burning insulation, which may not be noticeable in a WSC open flight deck. Once an electrical fire is detected, the pilot should attempt to identify the faulty circuit by checking circuit breakers, instruments, avionics, and lights. If the faulty circuit cannot be readily detected and isolated, and flight conditions permit, the battery master switch should be turned off to remove the possible source of the fire. However, any materials that have been ignited may continue to burn.

If electrical power is absolutely essential for the flight, an attempt may be made to identify and isolate the faulty circuit by:

1. Turning the electrical master switch off.
2. Turning all individual electrical switches off.
3. Turning the master switch back on.
4. Selecting electrical switches that were on before the fire indication one at a time, permitting a short time lapse after each switch is turned on to check for signs of odor, smoke, or sparks.

This procedure, however, has the effect of recreating the original problem. The most prudent course of action is to land as soon as possible.

The electrical fire could expand into a larger fire in the carriage. A fire in the cabin presents the pilot with two immediate demands: attacking the fire and getting the aircraft safely on the ground as quickly as possible.

Water Landings (Ditching)

Preflight planning for any flight where a water landing is possible should include personal flotation 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 five 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 difficult 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 flying 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, flying 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 flown 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 flight 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 flying 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, supplies 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/flares, and a large space blanket doubling as tarp.

Other items specific to unique terrain and climate zone should also be considered. For mountain terrain, a saw, shovel, water purifier, and 100-foot rope would be appropriate. For large bodies of water, flotation devices, extra water, and a water purifier would be added to the basic survival gear. If in desert conditions, bring a lot of water and hats for shade. In situations of extreme temperature changes, add both sun shading and layered clothing to the gear as appropriate.

Engine Failure After Takeoff

As discussed earlier in Chapter 7, Takeoff and Departure Climbs, proper takeoff technique provides lower pitch angles during the initial climb to provide the slowest possible descent rate for an engine failure after takeoff. The pitch angle and altitude available for engine failure at takeoff are the controlling factors in the successful accomplishment of an emergency landing. If an actual engine failure should occur immediately after takeoff and before a safe maneuvering altitude is attained, it is usually inadvisable to attempt to turn back to the takeoff field. Instead, it is safer to establish the proper glide attitude immediately, and select a field directly ahead or slightly to either side of the takeoff path.

The decision to continue straight ahead is often difficult to make unless the problems involved in attempting to turn back are seriously considered. First, the takeoff was probably made into the wind. To return to the takeoff field, a downwind turn must be made. This increases the groundspeed and rushes the pilot even more in the performance of procedures and in planning the landing approach. Second, the aircraft loses considerable altitude during the turn and might still be in a bank when the ground is contacted, resulting in cartwheeling (a catastrophe for the occupants, as well as the aircraft). After turning downwind, the apparent increase in groundspeed could mislead the pilot into a premature attempt to slow the aircraft to a stall. Finally, it is more than one 180° turn. For example, it is first a 225° turn in one direction, then another 45° turn in the other direction, totaling 310° of turn. [Figure 13-6]

On the other hand, continuing straight ahead or making a slight turn allows the pilot more time to establish a safe landing attitude. The landing can be made as slowly as desired, but more importantly, the aircraft can be landed while under control.

At airports where the runways are much longer than needed, there is typically ample runway to make a straight ahead landing. If a tight pattern is being used and the crosswind leg is started at the end of the runway, turning back the additional 90° to the runway could be the best option, depending on the suitability of landing areas straight ahead.

Depending on the specific design of the WSC aircraft considering weight, wing, and carriage, this maneuver can be performed with no reaction time and as low as 250 to 500 feet AGL. However, the pilot should determine the minimum altitude that such a maneuver would require of a particular aircraft. Experimentation at a much higher, safe altitude, 700 feet AGL as an example, should give the pilot an approximation of height lost in a descending 225° and 45° turn at idle power. Starting high above the ground at low bank angles and monitoring the altitude loss while doing the required turns to line back up on the runway provides a good reference. Finding the best bank angle to perform the required turns for this maneuver with minimum altitude loss is key to optimizing this maneuver and developing a habit if this maneuver is needed in a real emergency.

By adding a safety factor of about 30 percent to account for reaction time and no thrust from the propeller, the pilot should arrive at a practical decision height. The ability to make these turns does not necessarily mean that the departure runway can be reached in a power-off glide; this depends on the wind, the distance traveled during the climb, the height reached, and the glide distance of the aircraft without power.

This is a highly advanced maneuver with turns close to the ground. This should be practiced well into the training program with the instructor. For example, consider an aircraft which has taken off and climbed to an altitude of 350 feet AGL when the engine fails. After a typical 4-second reaction time, the pilot pulls down the nose, maintains control of the aircraft, and elects to turn back to the runway, losing 50 feet. [Figure 13-6, A to B] The pilot performs the 225° turn and loses 300 feet. [Figure 13-6, B to C] The pilot must glide back to the runway, losing another 50 feet. [Figure 13-6, C to D] The pilot must turn another 45° to head the aircraft toward the runway, losing another 50 feet. [Figure 13-6, D to E] By this time the total change in direction is 310°, the aircraft will have descended 450 feet, placing it 100 feet below the runway.

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 flat, 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 flat 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 flight 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.

Terrain Selection

A pilot’s choice of emergency landing sites is governed by the:

• Route selected during preflight 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 flying 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 flying at 500 feet AGL has 500 feet multiplied by five 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, flying in a downwind direction provides more area to be covered while flying 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 first selecting the desired general area than a specific 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 field
3. Obstacles in the final approach path and the field 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 final approach with some margin for error in judgment or technique. A pilot who overestimates the gliding range may be tempted to stretch the glide 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 flying 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.

Confined 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 final 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.

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 flight. A typical example is an aircraft forced down by engine failure.
• Precautionary landing—a premeditated landing, on or off an airport, when further flight 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-inflicted 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 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 find a relatively safe landing area whenever the flight 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 insufficient, stretching the glide without regard for minimum control speed in order to reach a more appealing field, 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 influenced by two other factors: the pilot’s financial 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 sacrificing 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 (flight 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 flight 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 benefit 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 fields 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 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 flat and open field 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 figures 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 firm 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 flight deck area. A careful consideration must be made considering wind, slope, and terrain.

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 an 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 conflicts 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 flying 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 fly the aircraft first, 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 preflight 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 fly 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 flying, or flying 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.
• 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 fire or could tangle during the deployment. Like any system, it can fail or not be operated properly, so there is no guarantee it will fire 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 inflates.
• 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).
• Before impact, put hands in front of face and keep arms and legs in and tight to body. 
• After impact, exit aircraft immediately.