Friday, 1 June 2018
EMERGENCY LANDING .v. CRASHING
Acknowledgements: AIR FACTS/Robert Reser
(Ed. Note: Of course, it’s part of your training, but how would you react if it happened for real? Robert’s excellent account of a possible scenario may be of help …. )
“The control of the aircraft during any approach and touchdown determines the difference between landing and crashing.
· A controlled aircraft flown to and through touchdown is a landing.
· An aircraft falling uncontrolled to the surface, even from just a few feet, is a crash.
If making an emergency off-field approach to an area with obstacles there is a strong tendency to try to make the aircraft avoid these obstacles. Often this is not possible in partial or unpowered forced landings. You must accept that it is going to be bad and continue flying the aircraft to a normal landing approach and touchdown, no matter what the condition of the landing area is.
· The landing gear is the first place you want contact with the surface. Its design is to absorb lots of energy.
· After the gear, the wings contacting obstacles will absorb some energy.
· The fuselage should be the last place you want to encounter an obstacle. You are idirect encounter with an obstacle can push the engine back into the cockpit. That is not good. A glancing encounter may be better.
The key is to use all means possible to slow down with minimum contact of the fuselage. This means you must have controlled the aircraft as long as possible. At touchdown, you will quickly become aware when you no longer have any control and have become a passenger!
Continuing the Approach
Having established a collision course on the final approach, you are confident you can make the field; but the field looks bad. There are trees and rocks just short of the touchdown point, and the field itself looks rough this low to the ground. It looked a lot better from a higher altitude. The tall grass is covering up a lot of rocks, ditches, and gullies. You have to live with the decision. In some cases, if recognised early enough, it may be possible to change landing fields, but be real sure before you decide to change.
Now you have to land on the selected area:
· Get it centred low and unmoving relative to the windshield. Attaining a collision course allows early confirmation of the landing area, and enables more time for controlling. If maintaining a collision course, you cannot miss.
· Consider if it is necessary to land on the area at slightly faster indicated-airspeed, or can you afford floating past some? Are you faster or slower than best glide indicated-airspeed?
· Keep the visual picture. Make the airplane go to it. But watch out when trying to make the airplane do something. Maybe it can’t.
· Be real careful using the elevator-pitch control now. You have the indicated-airspeed set with elevator-trim. All you can do with the elevator-pitch, before round-out and flare, is pull too much and stall. Don’t do that!
Extreme Landing Surface
If landing on an extremely bad surface, it is obvious a dismantling of the aircraft will follow:
· Consider using maximum nose up trim and full flaps for a minimum forward velocity. Then you don’t need the elevator-pitch control. The aircraft will be at its minimum indicated airspeed. The descent rate will be somewhat higher, and any change will require pushing the control wheel to allow the landing gear to absorb its maximum of both vertical and horizontal energies.
· There is no set way to make these rough field obstacle landings. You must have previously considered many different scenarios, but never decide there is only one way to do this. Resist the urge to pull back at this point – you must maintain best glide speed. When the time comes, you must do whatever it takes for that situation. It might not be any of those previously considered. Every landing approach is the same; the touchdown will be different in different circumstances and with different obstacles.
· Land the aircraft first; don’t let it stall.
Landing on a Relatively Smooth Surface
· You can set the indicated airspeed as if for a normal approach to a short field or soft field landing. Set the elevator pitch trim to this speed in anticipation of making a normal touchdown.
· Now, are you high or low? Most people tend to be high. You can utilise drag procedures like extension of the flaps or slips to increase descent.
· Are you low? You could be somewhat low, although by keeping the landing area centred on the windshield it should not be too low.
· You are below best glide indicated airspeed? Push it down to get best glide indicated airspeed again. That will extend the glide. If you are making the approach with full flaps for drag, retracting some will extend the glide distance.
· Do you feel you are too low for that? Push the elevator pitch control to gain best glide indicated airspeed, or even a little faster; level just above the surface, with minimum flaps for reduced drag. Now you will be in ground effect. That can extend your glide distance even more.
· Manoeuvre to a minimum forward speed. You are just above the ground, approaching the selected touchdown area. You are landing … wait a minute! This technique is the same for all landings. Your approach to touchdown is always the same. It is just another Visual Directed-Course toward a landing area. This is what you always do when making any idle-power approach … isn’t that interesting?
· The round-out and flare will likely be the last control inputs you can make, unless you are on a relatively smooth field. At this point, do whatever it takes. Keep flying through touchdown. You will recognise when you have become a passenger; until then, keep flying, and keep steering.
· The round-out has levelled the aircraft, and it is slowing and sinking. Continue to flare the nose up as normal. Just don’t stall. Any stall should occur only at touchdown. You have manoeuvred to a minimum forward speed. That is the best you can do. Do not try to make it fly slower. It can’t. It will stall if you attempt it.
· You are on the ground. It is rough. You’ve never experienced anything like this before; you just landed in rocks and gullies; the airplane just came to a rapid stop.
· Upon touchdown, you realised you had no control. You became a passenger.
· A forced landing doesn’t have to be a crash; sometimes it’s just an off-airport arrival. It may seem strange, but if this ever happens, you will think that. Why? Because I just told you so! It is now in your mind, and if the time ever comes, you will recall it… believe me, I know!
Did I say roll? Well, maybe so, maybe no. You are not finished yet. Most of the excitement takes place from touchdown to stop. You thought the approach was tough, but the landing is where it is at. What do you do during the landing roll?
· The main thing is, in what condition you need to be when the aircraft stops?
· YOU NEED TO BE CONSCIOUS! If not conscious, you can do nothing for yourself or for others.
· How do you do that? Well, you have to protect your head. Don’t let it bang around. You just instructed your passengers to do so. You have to do the same, if you can. Consideration of some techniques might help protect you during “touchdown to stop”.
· Staying Conscious: You just touched down on an unprepared field. Things are quickly going bad. How quick is quick? How long from touchdown to stop, if you land in the trees, rocks, and gullies? If you encounter irregular hard objects, the airplane is going to start coming apart. It may tip over on its back. No one can guess. No two incidents are ever the same.
· Everything takes time: The one thing you can depend on is that the deceleration will be quite fast. In many cases, you could expect touchdown to stop within three to five seconds. That is not a lot of time, but maybe it is enough to do something. During those few seconds of deceleration, you must recognise you are a passenger and protect your head to assure consciousness when stopped. That panel is not your friend – protect your head.
How long is three to five seconds? Try counting: one thousand one, one thousand two, one thousand three, one thousand four, one thousand five… That is a lot of time! What did you do during this time?
· One thousand one… at touchdown you quickly realised you had no control of the aircraft. Thrown forward by the rapid deceleration, you leant against the shoulder harness. You wrapped your arms around your head to keep from banging it against the glare shield and window post.
· One thousand two… you kept your eyes open, so you could react. Things were bouncing all over. When was this thing going to stop?
· One thousand three… It seemed like it had been three minutes. It was like slow motion.
· One thousand four… wow, it just flipped over on its back.
· One thousand five… It finally stopped. You were conscious, but hanging upside down. You thought “I’d better get everyone out of here”.
Anyway, you have stopped, upside down, hanging by your seatbelt, with a broken arm. Do you know what that feels like? Take time to consider this kind of situation as part of your experience training:
· Don’t worry. You are conscious, and if you get out quickly before the plane catches fire, you are home free. You will heal. Those bumps on your head will go away.
· Ouch! That hurts, dropping from the seat belt onto your head. Your left arm isn’t doing anything. You have to get these people out!
What do you think just happened?
· You were protecting your head and face while watching what was going on. Your brain works fast. It seemed like minutes rather than seconds for the thing to stop.
· You were lucky enoughto be conscious. You will be able to remember in detail all these events for the rest of your life. That is what happens when you have your eyes open during fast-moving events. It could be the same in a rolling car accident, a fall from a ladder, or any other fast-moving situation. Time seems to slow down… if you are watching.
· Your passengers are conscious too as they were not bumped so badly. They were protecting their faces, with arms wrapped around their heads, and leaning forward at impact, so… get them out of the airplane. The door is blocked? Kick the window out with your feet!
· That part is all over now. Take care of anyone hurt badly, then go sit together by a tree somewhere and try listening for the birds singing. It’s nice and quiet now. This is a way of relaxing for control of shock. There is nothing pressing to do for now.
· Rescue will come sometime in the next few minutes or hours. Don’t worry about food. It takes a few weeks to starve. Most people need to lose a pound or so anyway. And of course, you always carry water! ……….don’t you?”