dashvii(at)hotmail.com
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 Posted: Thu Oct 04, 2007 10:20 am Post subject: Lesson Plan for Aircraft System Failures Including Primary F |
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Doug, Laurrie, any others interested,
I have made this CFI lesson plan to be generic or non-aircraft specific. I don't have 20,000 hours in aircraft, but this was stitched together from various publications by many pilots who did. I would imagine that there's over a million hours of combined experience in this document! Check it out, see what you think. Hopefully I have minimized gramatical errors. I have references to personal experiences in there that might not be fleshed out as I tell them from memory. I haven't finished it all, as you can see there are a few through the list that I haven't posted anything under, andlast 10 topics or so on survival equipment and survival in different environments isn't finished. I have about 58 pages of text to reduce down and make something useful out of when I get around to it. Maybe someday this will help somebody out, Brian W.
Reference AC 61-67C Stall & Spin Awareness
"Don't drop the aircraft in order to fly the microphone” = Aviate, Navigate, Communicate
"Rule one: No matter what else happens, fly the airplane." = You are allowed to break any regulation needed in order to make a safe landing. If it comes down to it, you may have to sacrifice Navigation and Communication in order to crash into the softest thing possible.
"Fly it until the last piece stops moving." = The flight isn’t over until the prop stops moving, the aircraft is at rest, and the aircraft secured.
"If you're faced with a forced landing, fly the thing as far into the crash as possible." - Bob Hoover = Never give up! Flying, under control, into a brick wall is better than letting the aircraft loose control even for one second in an emergency.
Engine Failure, 3 S’s: Speed--Spot--Set-up: Establish best glide Speed without delay. Select and head toward a suitable landing Spot. If time and altitude permit, Set-up for the landing by configuring the airplane according to the operating handbook. If you're landing off-airport, don't forget to prepare the airplane so you can get out of it once it's on the ground. Consider opening or even jettisoning the door or canopy prior to landing.
Before Beginning a Maneuver: FOUR A's - Altitude, Articles, Aircraft, Airspace: Be sure you have enough Altitude to begin. Factor in the maneuvers to be flown, your current level of proficiency and physical conditioning, and an adequate safety factor. Verify that all loose Articles are secure--this includes windows, doors, canopies, and occupants! Verify that the Aircraft is configured properly--mixture, switches, engine instruments, carburetor heat/alternate air, flaps. Clear the Airspace for other traffic and make sure you're complying either with the provisions of FAR 91.303 or a waiver for the area.
Best Defense
• The old adage of the best defense is a good offense when we’re talking about aircraft emergencies holds true
• The right mindset and the right training will generally allow for an uneventful landing that may have otherwise resulted in a fatal accident.
• Let's face it, sitting on the ground is the time to figure that out because if you haven't thought about it before it happens you may not be in any mental condition to rationally consider your options.
• TAKE PREFLIGHT SERIOUSLY!
• Really check the controls to make sure that they move freely and in the proper direction. Listen and feel for anything unusual such as binding or scraping
• Be sure that everything in the cockpit is stowed away in an orderly place so that in an emergency, you won’t be looking for that map, so that in the event of turbulence you don’t have something hit you in the head or eye, and so that nothing is rolling around that could jam the controls
• Put down the flaps and, if they're electrically actuated, listen to the motor as they extend and retract. If the flap motor is struggling on the ground, it's likely to have real problems when it must overcome the aerodynamic pressure of the relative wind. If they are manually operated make sure that they both extend as commanded and that there is no binding or abnormal resistance.
• Don't panic. Do fly the airplane!
• Use the 3 prong strategy in an emergency, your training will take over, but may times your initial instinct will be the wrong action to take, so take your time.
1. Do Nothing
2. Think
3. Act
• When I take off, I assume I'm going to have to abort. If you put yourself in that mind state, you're ready for things to happen. Pilots should use the quiet moments during flight to ask themselves the what-if questions — where would I put down if my engine failed? What would I do if my rudder jammed?
• I constantly asked myself, where I would put down if the engine failed, what if my aileron jams at this point. I would takeoff using a Vy climb to put me in a better position if my engine failed on takeoff. I often use a short field takeoff. I often do a full power off approach from downwind so that I’d have a feel that I could make it if my engine failed on landing. Delivering aircraft, or flying cross country, I would mentally plan to land at the next airport each time in case the weather was getting bad, never forgetting to turn back to the last if the weather was getting worse ahead. I also constantly updated weather for the next point in question. In addition I picked out fields along the way to land in if I had to at that exact moment in time and couldn’t make it back to an airport.
Communications Failure
• Are your comm switches set in the right positions?
• Is the volume up?
• Do you hear yourself when you try to transmit?
• Check your headset plugs to see if they’re all the way in and not corroded
• Switch headset or mic
• Try speaker mode
• Switch to comm 2
• Check to see if your battery is discharging or see if your alternator is working.
• If on IFR flight plan but not IMC, land at nearest VFR airport; stay VFR
• Squawk 7600, transmit intentions “in the blind”
• Use AVE-F if in IMC, Assigned, Vectored, Expected, Filed
Transponder Failure
• Check to make sure that it is in the correct position (alt)
• Does the interrogation light illuminate?
• Recycle it – power off, power on
• Try switching through different codes and then back to your original (take care to avoid codes such as 7500, 7600, 7700, and 7777)
• Hit the faceplate (no really, this is in some POH’s, and works!)
Doors Opening In Flight or seatbelt stuck in door
• Maintain control of aircraft, fly the plane
• When at a safe altitude, slow the aircraft down and push out on the door followed by pulling it in and trying to latch it
• If this doesn’t work, make a normal landing and worry about it on the ground
Pitot-Static Failures
• Pitot static failures can come from a number of things such as ice, bugs, breaks in system lines, tape over static ports during painting or washing planes, etc.
• A good preflight will help make sure that these systems aren’t clogged on the ground.
• During the takeoff roll, make sure the airspeed is coming alive and gauges are in the green. Ask yourself if the airspeed “feels” right. If the airspeed isn’t coming up fast enough, abort.
• In flight if you have a failure, try to determine the cause. An clogged pitot tube will cause the airspeed to drop to zero while a clogged pitot and static will cause the airspeed to work as an altimeter, giving reverse expectations such as increasing speed in climb and decreasing in descent. The sounds of the air outside should be clues to whether you’re actually increasing or decreasing in speed. A blocked static port only will cause the Altimeter to freeze while the airspeed will overreport values.
• When dewpoint and temperature are close together, if the humidity is high, even if the temperature is not at freezing, the pitot can pick up ice. If equipped, turn on the pitot heat. (note, if also having alternator issues, this can drain the battery which may be used for flaps, lights, gear, etc. depending on aircraft. Use good judgment. If equipped and have to use pitot heat while discharging battery, drain backup battery first)
• Switch to alternate static source if equipped, using POH to determine altitude error. If not equipped, breaking the glass on a VSI can act as an alternate static source.
• When landing with inaccurate airspeed, ask yourself if it “feels right”. Use clues such as RPM increasing in descents and wind noise outside. Carry extra airspeed in landing and use full recommended flaps to lower stall speed. Consider a straight in approach and be sure to be established with attitude, configuration, and rpm set with plenty of altitude. This will fix your airspeed within a certain speed range and provide some additional protection.
GPS Failure
• In this day and age we have come to rely on the GPS too much
• Fly every flight as though you were going to dead reckon the entire way.
• Use other navigation aids, be sure to identify station if using VOR or NDB systems
• It has been said that many aircraft in the future may go back to using LORAN as a backup for GPS, and may become integrated into the system so that you know that your GPS has lost integrity and went into LORAN mode. This essentially works like a GPS.
• Use the GPS as you would a VOR, noting distances from various airports or identifying marks. Mentally overlay this on a Sectional, possibly making updated marks on the Sectional along with noting the time.
• If the unit fails, calculations can be made for speed time and distance to find your way.
• Dual GPS units will allow for a malfunction of one system, but not a loss of satellite signal integrity
• If you loose a minimal amount of satellites, the system will eventually come back, but in the meantime you navigate by other means
• Don’t be too proud to ask ATC for help with a DF Steer
AHRS Failure
• Check that AHRS Circuit Breakers are in
• Use standby instruments
• If in a cloud and have the ability, used a timed 180 degree standard rate turn
• If attempting a reset in flight, try to maintain a straight and level attitude, stay in clear weather, the system will update and get tighter over time.
Inadvertent Flight Into IMC
• Remember your training and execute a level 180 degree turn out of the cloud as you would under the hood using a timed standard rate turn.
• If that doesn’t work, continue to fly the plane, do not descend
• If you have a frequency for an air traffic controller, tell them your situation and they can help guide you out.
• Try to keep level flight by maintaining a power setting and looking at the attitude indicator to keep the blue side up. Make sure that you’re not descending or climbing and then try to trim for that power setting.
• Once clear of clouds, maneuver to stay clear and land at the nearest possible airport.
Inadvertent Flight Into Icing
• Follow specific manufacturers guidelines
• Probably going to add a percentage to your normal approach speeds
• Probably going to make a no flap landing
• Potential for no or partial landing gear retraction.
• Do not retract gear after they are down and locked as this may freeze them in the up position
• You can simulate icing by doing a no flap approach at a higher than normal approach speed (remember this will result in a significantly longer ground roll)
Unusual Atitudes
• RELAX: Most unusual attitudes in the aerobatic environment are pilot-induced. Trying to force the airplane to fly without enough energy, or with misapplied controls, or both can quickly lead to an inadvertent stall/spin or inverted attitude. The airplane will usually return to a more normal flight mode by simply relaxing your grip on the controls--even letting go--when a maneuver first goes sour.
• Even experienced pilots would be hard pressed to save a botched maneuver. If it's that bad, it's probably a zero anyway. Why compound matters by transitioning into an unusual attitude with minimal energy? Abort those errant maneuvers early instead. You'll maintain control and you'll have more options available.
• Your attitude indicator might tumble in the advent of an extreme unusual attitude and become unreliable.
• Looking outside may fool you as well. An extreme nose down attitude will look the same whether inverted or right side up
• Your best indications will be visually, but the instruments such as airspeed indicator and the altimeter will reinforce that. Look at both and determine an appropriate course of action. Also the sound of increasing or decreasing RPM and airspeed can be clues.
• If the airspeed is increasing and the altimeter decreasing, power to idle, level the wings and slowly pull out of the dive. (airspeed can get past Vne in a couple of seconds in this attitude)
• If the airspeed is decreasing and the altitude increasing, full power and decrease the angle of attack, and then level the wings.
• If you find that you’re in an inverted attitude follow these steps: Power--Push--Roll: In the aerobatic environment, if you find yourself upside down when you shouldn't be, reduce the Power (especially if you're descending). Apply a slight Push on the elevator to reduce the positive g-load and to retard the rate at which the nose may be falling through the horizon. Apply full aileron, followed by coordinated rudder, to Roll the airplane upright. Avoid pulling while you're rolling--roll upright first, in a low-g environment, then recover the pitch attitude.
Stalls/Spins
• Since 1976 there have been 4,800 stall spin accidents recorded in the U.S. This represents nearly 12% of accidents recorded.
• Both stalls and spins can happen at ANY attitude and airspeed!
• A stall can only happen when you have exceeded a critical angle of attack, therefore if you reduce the angle of attack the aircraft will come out of the stall. (lessons learned: Not all aircraft require shoving the nose forward to break the stall, but simply allow the control to pass through neutral by relaxing back pressure. Additionally some aircraft will remain in a nose up attitude even when fully stalled, with a high rate of descent)
• One-third of stall/spin accidents in an NTSB study involved pilots with more than 1,000 hours of flight time. The median pilot experience of those involved in stall/spins was 400 hours
• The pilots who are most at risk have logged fewer than 1,000 hours; who is on a daytime pleasure flight in good weather; who is in the traffic pattern; and who is either turning or climbing. Leading up to the inadvertent stall/spin, the pilot will be distracted into making a critical error in judgment. Fixation on the unfolding accident will effectively render (1) in (3) pilots deaf to a blaring stall warning horn. And pilots with fewer than either 500 hours total time, or 100 hours in type, are more likely to encounter an inadvertent stall/spin than to have a genuine engine failure (i.e.: a random-event engine failure, not one attributed to such pilot errors as fuel mismanagement).
• Most instructors teach no more than 30 degrees bank in the traffic pattern. Aerodynamically speaking the degree of bank at 300 or 3000’ is the same. Instead pilots try turning flat by cheating with rudder, which can cause a cross-controlled situation and lead to a stall/spin in the pattern.
• The notion that mandatory spin training was rescinded in 1949 because “we were killing more pilots during spin training than the training was saving” is a myth. “This amendment eliminates spins from the pilot certification requirement and, in lieu thereof, provides for dual flight instruction in the prevention of and recovery from power-on and power-off stalls entered from all normally anticipated flight attitudes. It is believed that the deletion of the spin requirement and the placing of greater emphasis upon the prevention of and recovery from stalls will result in greater air safety in two ways: (a) it will emphasize recognition of and recovery from stalls which, on the basis of available accident statistics, has proved to be the most dangerous maneuver to pilots; and (b) elimination of the required spin maneuver will act as an incentive for manufacturers to build, and operators of schools to use, spin-resistant or spin-proof aircraft.”
• If you inadvertently enter into a spin, the most effective way to recover is a 4 step process:
Power - off
Aileron - neutral
Rudder - opposite
Elevator – through neutral (decrease angle of attack, which might mean pulling back if inverted in order to break the stall)
• Ailerons should be kept neutral because aileron application may alter spin characteristics (i.e. become divergent)
• It is possible that a person may become disorientated if the spin becomes divergent or if it becomes inverted. The best way to recover when you reach the rudder input is to mentally describe which shoulder is moving forward in the spin. Then apply the rudder input to the same side. This works whether diverging, inverted, flat, or normal spin.
• It is possible to have a broken throttle linkage and then entering into a spin. In this case, use the mixture to reduce power.
• Although it used to be required for all private pilot applicants to demonstrate a spin recovery, it no longer is a requirement. Though beneficial, unfortunately the infrastructure does not exist for spin training to be conducted safely on a national scale. My recommendation is to take a course in spin (aimed at understanding spin dynamics and teach spin avoidance!) AND upset attitude recovery at an aerobatics flight school from qualified professionals.
Mixture/Throttle Failures
• Example (mixture control broke on Esqual that I was test flying at 12,000 feet)
• Second Most Common type of control failure is a linkage broke to the throttle, and it’s usually stuck wide open!
• First, slow down by climbing
• Once within operating limits, lower gear, deploy full flaps
• Now control power with mixture (WWI airplanes used ignition controlling which was full or no power typically) Full mixture for power, cutoff for idle. As long as prop is turning and magnetos are left on, engine will continue to run
• When assured a landing, mixture to idle cutoff and touchdown normally
Fouled Spark Plugs
• Fouled Spark plugs are a common problem in aircraft engines. It will cause the engine to run rough
• Usually this is caused by running the engine too rich, either in flight or on the ground.
• In order to “clean” the plugs, you must lean the mixture, which increases the cylinder head temperatures and burn the carbon off of the spark plugs.
• If roughness continues, proceed to the nearest airport and make an emergency landing. The spark plugs may need to be changed.
Hydraulic Pump or Gear failure
Tires
• If missing a wheel or tire on takeoff while still on the ground, try to keep the nose going straight with rudders and single breaking, even if the aircraft is skidding to one side, increasing brake pressure as you slow.
• Unlatch door or canopy, pull safety belts tight, before landing, shut down engine when landing assured, exit aircraft after it has come to a full stop
• If missing a wheel or tire after airborne, leave gear down, get visual confirmation, and land on good wheel side of the runway to allow skidding to bad tire side. Follow the rest of the above procedure.
• If a nosewheel is damaged, missing, or blown: plan a soft field landing where you keep the nosewheel off as long as possible. Once assured a safe landing secure engine, prop to fine pitch.
Fires on Ground
• If cranking, continue to crank engine
• If engine starts power up to at least 1700 rpms to suck flames in
• If engine fails to start, throttle full, mixture idle, continue cranking
• Secure engine, master off, fuel shutoff off, ignition off
• If able, use fire extinguisher, if not get a safe distance away
Fires in Flight
• Example: smoke in the cabin during a flight after maintenance had been done. Once on the ground I found that oil spilled on the engine block had burned off and released the smoke. There was no danger, but without an inspection on the ground there was no way of knowing.
• Fires in flight take many different forms and can be among the most serious of in flight emergencies. These require that appropriate and prompt action be taken.
• All fires or evidence of an impending fire (i.e. visible smoke, sparks, or the smell of something burning) must result in an emergency landing, even if you think the fire is out.
• NEVER reset a circuit breaker more than once, it was thrown for a reason. Some would say that if the circuit breaker isn’t critical (like the actuator for the gear) to never reset a thrown breaker until you get it checked out. If it is something critical, but only used at a certain time, reset it only when you need it. (like gear)
• If you smell smoke or see smoke in the cockpit
• If the fire is coming from the engine compartment, shut off fuel to that engine, shut off the alternator, but allow the engine to continue running until it runs out of fuel in the lines and then shut off the magnetos to the engine.
• Wing fires can be caused by heated pitot tubes, wing lights, electrically actuated hydraulic gear pumps, or heated wing leading edges. Shutting off all electrical equipment to that wing would be appropriate, along with a side slip to keep the flames away from the cabin.
• The number one thing to remember is to keep control of the aircraft. If you can, always keep a pair of nomex gloves in your flight bag so that if there are flames or if the controls become hot, it will be easier for you to touch them.
• The two biggest fears are burning to death, or that the control cables will burn through. Accelerants such as hydraulic fluid, fuel, magnesium metal parts will shorten your time to make a safe landing. If there are visible flames outside the aircraft, if you have the altitude, push the nose over to increase speed to an incombustible mixture even if this means going over Vne. If traveling beyond Vne, pull out smoothly and slowly to keep from overstressing the aircraft.
• Do not look for a runway unless you are in the immediate vicinity of the airport. If you are in the airport area, declare an emergency and make an immediate turn towards the runway. If possible, alert fire/rescue at airport to be waiting. If you’re not close to a runway, put it down in a field, preferably into the wind and a field without any furrows. As much as possible make sure the field isn’t full of tall dry grass or the such that may trap you in a fiery field once safely down. Fire/rescue will not be able to be there, but if you can alert a nearby tower to your position, then local fire/rescue may be there soon.
• Unlatch the doors prior to landing so that you can escape
• If the fire is in the cockpit, consider putting the aircraft down with landing gear in the up position to come to a stop quicker.
• Any passengers should be made aware that after the aircraft comes to a stop, where the exits are and to exit quickly. Also tell them to unlatch doors prior to landing so that they can’t become jammed. All passengers should meet at a predetermined location, if landing into the wind, at least 100 yards in front of the aircraft (to avoid standing in fire and smoke downwind) and told not to come back to the aircraft under any circumstances.
Pressurization Failures
• Check pressurization passing through 10k
• I recommend going to an altitude chamber to recognize your personal symptoms to hypoxia. (at 10 minutes and 25,000 feet, mine were blue fingernails, up to the second knuckle! And blue lips. I had a minimal slow down in reaction time, but obviously degraded mental faculties and becoming hyper-focused on one thing. Others included feeling sick, being cold, being hot, laughing uncontrollably, and some just totally lost their minds!)
• Mentally train yourself to realize that when you think that you are having unusual or irrational thoughts to check for your symptoms, check the O2 system if there is one, and to follow your checklist for emergency descent.
• Go on oxygen if supplied, even if below 10,000 feet, or 5,000 feet at night. Hypoxia effects can be extremely quick, or take time, but oxygen is an almost instant cure!
• If on diluter demand and showing symptoms, check pressurization systems and consider switching to pressure demand
• One technique that I have used is initiating an emergency descent while trimming for a 500 fpm rate of descent. Forcing the plane to greater than 500 fpm. If you pass out the plane will continue on a descent and hopefully you’ll wake up before the plane impacts terrain. Even if you don’t it is possible to survive the plane impacting level at this rate of descent.
Crew should remain on oxygen after any type of pressurization failure for the remainder of the flight. Also should check the regulators to make sure oxygen is flowing.
Control System Malfunctions (Example = United 232)
• NEVER, EVER, GIVE UP!
• It is estimated that approximately 3,600 control system malfunctions occur every year in the United States. About 11 of these result in an accident, of which not all are favorable. These are pretty positive odds of a good outcome!
• These types of failures are more likely to happen during early test flights or return to service flights. Generally these flights are done with no turbulence and little or no wind, however, most people who are not test pilots will not have this luxury. It may occur in IMC, during weather, and turbulence. We need to practice these situations so that we may know what to do when the situation exists for real
• Being ready for a control system malfunction requires the right mindset and training.
• Always practice these problems with 1,000’s of feet between you and the ground so that you don’t put yourself in unnecessary danger.
Aileron
• Third most common type of control failure
• Perhaps the easiest type of control system failure to deal with
• Do not try to push past the obstacle as it may increase the chance of structural failure and cause a more serious condition.
• Instead, transition to a nice, stable side slip
• Make sure that your turns are in the direction of your slip
• Carry extra speed as you are in a cross controlled configuration and a resulting stall would surely end up in a spin at a low altitude.
• Take advantage of the wind to help you keep aligned with the runway by keeping the wind at your low wing. This way you’re essentially making a normal crosswind landing.
Rudder
• Stuck rudders, simultaneous aileron and elevator failures, and trim failures round off the list of common control problems.
• When the rudder becomes stuck in the fully deflected position, the solution is the same as when the ailerons become stuck — a stable slip that will let you fly right back to the runway and make a straightforward crosswind landing.
• Carry extra speed as you are in a cross controlled configuration and a resulting stall would surely end up in a spin at a low altitude.
• Don’t forget that by opening your doors on either side of the cabin you have a rudder!
Elevator
• (Example = crop duster at Jonesboro)
• This is the most common type of control system malfunction/failure
• If the elevator or stabilator becomes jammed, the initial instinct to apply pressure to overcome the jam is the wrong approach.
• Leaving the elevator in the same position will keep the cables from being broken
• Control can be maintained by the use of trim, flaps, and power to control pitch
• Remember that flaps will increase drag and pitch the nose down. This will help most at altitude, but not a good idea to extend when on approach to landing
• A combination of power and trim will give the best results for fine adjustments. Power will have a delayed effect on pitch, but trim will be nearly instant.
• Optimally, during the flare you will have the ability to use at least half the trim for nose up. Power is then secondary and will now allow more for a softer touchdown than to be used for pitch control.
Multiple
• Stuck rudders, simultaneous aileron and elevator failures, and trim failures round off the list of common control problems.
• A combination aileron and elevator failure means it's time to let go of the yoke and work those rudders. You should be able to direct the airplane any way that you want it to go just using rudder and pitch trim.
• Don’t forget the use of your doors, opening them on one side or the other to use for rudders and yawing flight.
Trim
• Example: First flights in Esqual with no trim control
• Note that trim controls may be wired backwards
• Finally, trim failures generally can be overcome with elevator, although the exercise may be exhausting as you muscle the airplane into the desired attitude.
Flaps
• Tie for the 3rd most common type of failure
• If flaps simply fail to deploy, check the circuit breakers
• If circuit breakers are fine, land without any flaps
• A much more serious problem is an asymmetrical flap extension
• The best way to deal with this is in training. Students keep their hands on the flaps until they have verified that both flaps are in the correct position and no uncommanded roll is encountered. If your hand comes off the flaps it has been shown that it is unlikely that under duress that you will come back to the flaps in a timely fashion.
• If a split flap is encountered, most of the time it will retract.
• If it only partially retracted, try using ailerons and rudder to help roll yourself to the upright and fly in a side slip.
Structural Failures
Crashing
• There is an art to crashing!
• When at all possible, land in a level flight attitude at the slowest possible airspeed, with minimal rate of descent.
• Always wear seatbelts, either while on the ground or airborne, if the plane flips over on the ground it can keep you from having head injuries, in flight it can keep you in place if you hit turbulence.
• If building, make sure that you have chosen a belt webbing of at least 0.09 inches thick, preferably made of Dacron vs. Nylon. (dachron stretches slightly and allows more dissipation of energy, while still holding you securely in place)
• Dual shoulder restraints are preferable, with lower body restraints.
• The strap over the shoulder should make an angle of approximately 25 degrees Angles less than 25 degrees may cause spinal compression as the pilot's body moves forward and under the shoulder harness. Strap angles greater than 25 degrees with the horizontal may not provide the restraint necessary during a high-G stop.
• The lower belts should lie across your hips, not your upper thighs nor your lower abdomen. If the hips aren't restrained in a crash, your body could slide under the belt, causing abdominal or spinal injuries.
• Seating position is another important factor in crash survivability. As we discussed in Part 1 of this series, stopping distance is the key to preventing injuries. The typical cropduster has approximately eight to ten feet of distance between the pilot's seat and the tip of the airplane's nose. That's an extra eight to ten feet of distance in which to decelerate the airplane's occupants. If a pilot only needs 12.3 feet for a 9-G deceleration, then eight feet of crushable nose area give the pilot 65% of that distance. Many light twins have similar distances between pilot seats and the tip of the airplane's nose. Smaller training airplanes, however, can have only four to six feet of distance between pilot seating positions and the airplane's nose. What does all this mean to you?
It means that you may gain a slight advantage in survivability by increasing the distance between you and the airplane's nose. You and your passengers would do this by moving your seats as far aft as is practical. In most smaller airplanes you can gain nearly a foot to a foot-and-a-half advantage in distance by sliding the seat back.
In some cases this is more practical for the front seat passenger than it is for the pilot. After all, the pilot must still fly the airplane. If the pilot is short, he or she needs to remain close enough to manipulate the flight controls. Taller pilots can easily slide the seats aft before impact (if they're not already against their aft stops).
• Passengers should also place something protective over their face prior to impact. A jacket works well in these instances. This tends to be more difficult for the pilot to do since he or she still needs to fly the airplane. But, where possible, pilots should do the same prior to impact.
• Gear up or gear down? First, if the surface is hard (dirt, sod, asphalt, concrete, etc.) it makes sense to land with the gear down. If the surface is soft enough to cause the wheels to catch, possibly flipping the airplane over, then land with the gear up. Surfaces like water, mud and swampland could easily cause the airplane's nose to dig in and flip the airplane if the gear were extended. Second, consider the advantages of extended gear when forced to land in the tree tops. The landing gear becomes a breakable impact-absorbing structure which may help retard forward motion through branches. Additionally, depending on the type of gear, it may offer better deceleration in the vertical direction. There are concerns, however, about crashing airplanes with the gear down. It's possible that the gear could tear into a fuel tank as it rips away during impact, leading to a fire. This is more of a concern for low-wing airplanes than it is for those with high wings. Also, during impact, the gear might enter the cabin and injure the passengers. Finally, on some airplanes, part of the gear lies directly underneath or ahead of the fuel tanks. Thus the gear may provide a barrier of sorts to minimize the chance of fuel tank puncture. How do you know if this is true for your airplane? You don't, unless you ask. Find a competent mechanic and ask him or her about the gear and fuel tank structure or call the airplane manufacturer for help with this information.
• USAF Flight Safety Research Branch. This study indicated that, in any sort of terrain, forced landings in tricycle-geared airplanes are less likely to result in injuries or fatalities if the landing gear is down.
• Short field distances are based on an approach speed of 30% to 40% above stall speed (the typical speed most POH's recommend for short field approaches). But who says that you must approach at 30% to 40% above stall speed when trying to get the airplane down in a confined space in an emergency? I've known pilots to use values of 10% to 20% above stall speed for short field approaches. Of course, they have power if they need it and they are quite cognizant of operations on the back side of the power curve. Nevertheless, in an emergency, if you had to get an airplane down in a confined area, and you were skilled at airspeed control, it's perfectly reasonable to make an approach with a much lower short field approach speed. Remember, we're talking about an emergency here, not normal flight conditions. The lower approach speeds should dramatically decrease your obstacle clearance and landing roll distances.
Sometimes, it may be wise to force the airplane down onto the ground if a collision looks imminent. Considering this circumstance, raising the flaps on touchdown or even during the flare is another reasonable action. Perhaps you may even retract the gear after touching down as a deceleration aid.
Emergency Egress
• THREE H's - Handle, Headset, Harness: Grab the emergency Handle (it's often red, or should be) and jettison the door or canopy (Note: Decathlons and Citabrias have a retaining pin that must be removed first to unlock the handle. Although you generally pull the handle, in some Citabrias it must be pushed). Most aircraft will not have a door or canopy jettison option. This increases the chance of hurting yourself during egress
• If you have a side mounted door, try to yaw the airplane to the side that your door is on. This will help shield the door from the wind and allow you to open it easier. It will also allow the tail to be deflected away from your exit as much as possible.
• If you have a forward latched canopy it will be difficult to egress. The easiest method is to unlatch the canopy, following the completion of the 3 H’s, invert the aircraft and push the nose forward violently. Let go of the stick as you become light in the seat and this should throw you clear.
• If you have an airplane that is a pusher prop, be sure to shut down the engine and make sure the prop has stopped turning before you egress.
• Remove your Headset and drop it to the side (If you're wearing a helmet, disconnect the headset cord from the airplane).
• Undo your Harness and move the loose ends away from your body. Exit the airplane head first. As soon as you're clear of the airplane, LOOK at the rip cord handle (the D-shaped ring), GRAB it with both hands, and PULL!
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