Take-off technique -taking weight off nosewheel?
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Take-off technique -taking weight off nosewheel?
During a dual check recently, the instructor said I must pull back on the stick during the take off run in order to "take the weight off the nosewheel." I said why, whats wrong with the nosewheel?
He said it was the weakest part of the aircraft and could cause nosewheel shimmy if I did not do it. I then perused manufacture's POH for Cessnas and Pipers and could not find any reference to this technique, apart from soft or rough field take off where it is recommended you take the aircraft off the ground as soon as practical in a slightly tail low attitude.
Anyone else heard of this problem with weak nosewheel structures, and if nosewheel shimmy is prevalent, isn't this a shimmy damper unserviceability problem which should be reported in the maintenance release?
I asked a friend of mine who flew Barons and now flies F28's, and they don't take the weight off the nosewheel - so is my instructor teaching horse-s**t?
He said it was the weakest part of the aircraft and could cause nosewheel shimmy if I did not do it. I then perused manufacture's POH for Cessnas and Pipers and could not find any reference to this technique, apart from soft or rough field take off where it is recommended you take the aircraft off the ground as soon as practical in a slightly tail low attitude.
Anyone else heard of this problem with weak nosewheel structures, and if nosewheel shimmy is prevalent, isn't this a shimmy damper unserviceability problem which should be reported in the maintenance release?
I asked a friend of mine who flew Barons and now flies F28's, and they don't take the weight off the nosewheel - so is my instructor teaching horse-s**t?
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I personaly teach the student to raise the nose wheel off the ground into the t/o position and then let the aircraft fly when ready. This helps the 'snatch and fly' technique I've come across where the student watches the ASI intently for the rotate speed and upon reaching, procedes to heave the aircraft into the air with the real possibility of airspeed decay close to the ground with resulting altitude loss whilst regaining airspeed. Also the the climb attitude is set before take off which I find is a easier transition from ground roll to airborne and also less friction with a wheel removed from the equation.
Just my thoughts.
PS I find nose wheel shimmy's quite common but mainly on landing roll. same could happen on take off roll if student tries to 'fish' the aircraft off the ground (ie constantly moving cc back and forth, trial & error type flying)
Just my thoughts.
PS I find nose wheel shimmy's quite common but mainly on landing roll. same could happen on take off roll if student tries to 'fish' the aircraft off the ground (ie constantly moving cc back and forth, trial & error type flying)
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My instructor course instructor taught me never to say "Pull back on the stick", rather to say "Apply back pressure". Over pedantic? Not really, students will take what you say quite literally.
A little bit is needed on the take off roll, but not much. I've seen a few tail scrapes on take off and landing on 152s and Tomamhawks, caused by people "pulling back on the control column" when they should have "applied back pressure"
Shimmy is mostly a landing problem, and easily stopped by applying slight back pressure and gently applying the brakes to get away from the resonance that is causing the problem. Shimmy dampers only damp it, they don't eradicate it. Nosewheels are pretty tough old things. I'd be worried if the LAME told me there was any weak part on any aircraft I was flying!! They don't like being slammed into the ground, but then who does?
A little bit is needed on the take off roll, but not much. I've seen a few tail scrapes on take off and landing on 152s and Tomamhawks, caused by people "pulling back on the control column" when they should have "applied back pressure"
Shimmy is mostly a landing problem, and easily stopped by applying slight back pressure and gently applying the brakes to get away from the resonance that is causing the problem. Shimmy dampers only damp it, they don't eradicate it. Nosewheels are pretty tough old things. I'd be worried if the LAME told me there was any weak part on any aircraft I was flying!! They don't like being slammed into the ground, but then who does?
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Well some aircraft in my 'fleet' shimmy like Shakin Stevens on speed-acid during takeoff and the required technique is to ease the nose up through the run. I consider myself fully prepared for the world where you have to 'work round' the FMC etc rather than just fix the damn silly thing!
WWW
WWW
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Thanks for the explanation for the shake, I thought it was a built in slimming aid for fat pilots !
I was tought to keep the pressure off of the front wheel by applying slight back pressure at all times, even when taxying, I understand that the front strut should always be treated gently otherwise 'shimmying' soon sets in due to wear. Mind you, I did fly a 152 on to a short field landing, had to apply the brakes like mad and thought the vibration was going to cause the engine to fall out, the shake was so bad, I had blurred vision !!
I was tought to keep the pressure off of the front wheel by applying slight back pressure at all times, even when taxying, I understand that the front strut should always be treated gently otherwise 'shimmying' soon sets in due to wear. Mind you, I did fly a 152 on to a short field landing, had to apply the brakes like mad and thought the vibration was going to cause the engine to fall out, the shake was so bad, I had blurred vision !!
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Thanks for the first replies chaps. So what we have got so far is that no one uses the manufacturer's POH recommendation, but everyone has their own pet technique. I find no trouble accepting the POH technique. But I pity the poor students who take the time to read the POH only to be told by their instructor to do it his way and not the POH way. That is why I started this thread to get a discussion going on non-POH-standard techniques used by flying instructors.
Also, if the nose-wheel shimmies on take-off and landing, then apparently the fix is to fly an unpublished technique to minimize the shimmy. Why not u/s the shimmy in the tech log and eradicate the defect altogether?
I know of one flying school operating C150's that deliberately keeps the aircraft tyres deflated to half the recommended pressure in order to minimize chronic nose-wheel shimmy on taxying, take-off and landing. The operator refuses to consider remedial servicing.
As far as scarping along the runway with the nosewheel off the deck in the climb attitude, surely the take off performance charts would become invalid due to extra drag. And if litigation followed an accident, I would have thought that the instructor would be on very thin ice if it was proved he was teaching a student a technique contrary to the manufacturer's POH.
Many accident reports that I have read indicate that the aircraft left the ground prematurely in a nose high attitude due to the student/pilot taking the weight off the nose-wheel, and with extra induced drag, failed to accelerate and simply ran out of strip. Best stick to the manufacturer's POH, chaps - it's safer and your backside is covered if something goes wrong.
The real danger of the myth of the taking the weight off the nose-wheel technique is that there is no way of knowing for certain how much stick force is required, and exactly how far off the runway the nose-wheel is floating. A little gust of wind on the nose and you have a Cessna skipping airborne in ground effect. Then the fun occurs with the speed hovering on the stall. I can hear the stall warning sounding intermittently from here!
Perhaps those instructors that are convinced that their pet theories are technically sound, should write to the aircraft manufacturer and suggest the test pilots have got it all wrong. I am sure that the manufacturer will be grateful for the advice.
Don't forget to attach documentary evidence of your flight tests done over controlled conditions to back your "facts."
Also, if the nose-wheel shimmies on take-off and landing, then apparently the fix is to fly an unpublished technique to minimize the shimmy. Why not u/s the shimmy in the tech log and eradicate the defect altogether?
I know of one flying school operating C150's that deliberately keeps the aircraft tyres deflated to half the recommended pressure in order to minimize chronic nose-wheel shimmy on taxying, take-off and landing. The operator refuses to consider remedial servicing.
As far as scarping along the runway with the nosewheel off the deck in the climb attitude, surely the take off performance charts would become invalid due to extra drag. And if litigation followed an accident, I would have thought that the instructor would be on very thin ice if it was proved he was teaching a student a technique contrary to the manufacturer's POH.
Many accident reports that I have read indicate that the aircraft left the ground prematurely in a nose high attitude due to the student/pilot taking the weight off the nose-wheel, and with extra induced drag, failed to accelerate and simply ran out of strip. Best stick to the manufacturer's POH, chaps - it's safer and your backside is covered if something goes wrong.
The real danger of the myth of the taking the weight off the nose-wheel technique is that there is no way of knowing for certain how much stick force is required, and exactly how far off the runway the nose-wheel is floating. A little gust of wind on the nose and you have a Cessna skipping airborne in ground effect. Then the fun occurs with the speed hovering on the stall. I can hear the stall warning sounding intermittently from here!
Perhaps those instructors that are convinced that their pet theories are technically sound, should write to the aircraft manufacturer and suggest the test pilots have got it all wrong. I am sure that the manufacturer will be grateful for the advice.
Don't forget to attach documentary evidence of your flight tests done over controlled conditions to back your "facts."
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Hudson:
I certainly agree as far as your last post is concerned and must also say that I am curious about the statement of "holding the ac in the takeoff attitude untill lift of occurs". Most of my time teaching have been in Cessna's, but have flown a slew of other types. If trimmed correctly for takeoff, most all will fly of the ground when a little bit of backpressure is applied at the proper speed. As far as the shimmy damping is concerned, it is a real problem, specially in trainer's, the problem sometimes is easy to fix, change the actual unit, but many times it is neccessary to overhaul the whole strut assembly due to excessive clearances in the hardware. Easing the load on the nose will many times stop the problem, but you are correct that it is merely a short term solution and proper corrective action should be taken.
I certainly agree as far as your last post is concerned and must also say that I am curious about the statement of "holding the ac in the takeoff attitude untill lift of occurs". Most of my time teaching have been in Cessna's, but have flown a slew of other types. If trimmed correctly for takeoff, most all will fly of the ground when a little bit of backpressure is applied at the proper speed. As far as the shimmy damping is concerned, it is a real problem, specially in trainer's, the problem sometimes is easy to fix, change the actual unit, but many times it is neccessary to overhaul the whole strut assembly due to excessive clearances in the hardware. Easing the load on the nose will many times stop the problem, but you are correct that it is merely a short term solution and proper corrective action should be taken.
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Hudson old boy, you are being taught to fly by your instructor, not by the pilots operating handbook. Are you going to abandon every takeoff when nosewheel shimmy is encountered and then snag the aeroplane? You’ll find your club membership revoked after about three weeks and half the light aircraft in the UK grounded if you do.
There is nothing at all wrong with applying backpressure throughout the T/O roll to relieve nose shimmy if you are taught how to do it.
Thundering along the runway with the front leg shaking itself to bits until Vr will lead to total failure quite soon. Personally I agree with Cessnaboy that the sprint and snatch technique is overly common in PPLs and is more dangerous. Fly by attitudes rather than instruments during T/O and you can’t go wrong. Similarly students are more likely to ‘apply back pressure’ if they are easing on the elevator from the first 50ft of the run rather than waiting until Vr before daring to move the controls.
I urge you to be wary of the POH when learning to fly. It is written by test pilots and concerns itself with the best way for other pilots to operate the aircraft. It does not concern itself with the best way to be taught how to fly. We instructors often tell half truths to get you around a problem. If your instructor is stuck with aircraft that shimmy and his boss won’t fix them then what can he do other than teach you to ‘fly around’ the problem.
I very much doubt he is teaching you something hazardous as he has got to send you off solo sometime and the last thing he wants to see is you staggering into the sky only to stall on takeoff and crash back to the ground.
Get used to the fact that all pilots have pet methods and particularly when it comes to instruction. Even in well standardised units such as RAF UAS squadrons there are differences. Certainly between airlines there are different ways of doing the same thing. There is a lot of science in aviation but some art does remain.
Your illustration of an aircraft struggling down the runway nose high and staggering into the air with the stall warner blaring is not really valid as I very very much doubt this is what your instructor is doing or telling you to do. It is perhaps what a PPL might do if he had heard about nose wheel shimmy techniques but had never been taught them… I remember a bold young PPL aged 17 who was told how to use the ADF by a mate of his. He got terribly lost and very scared a few weeks later when he tried to use it and got in a terrible muddle. I learned that lesson well and now never use a piece of kit or technique unless I have been explicitly taught it…
As for half inflated tyres that is dangerous.
Best of luck with your course. If I was your instructor I would be very impressed that you had read the POH – most thumb through it on day one and then use it as a convenient table leg leveller for the rest of their training!
WWW
There is nothing at all wrong with applying backpressure throughout the T/O roll to relieve nose shimmy if you are taught how to do it.
Thundering along the runway with the front leg shaking itself to bits until Vr will lead to total failure quite soon. Personally I agree with Cessnaboy that the sprint and snatch technique is overly common in PPLs and is more dangerous. Fly by attitudes rather than instruments during T/O and you can’t go wrong. Similarly students are more likely to ‘apply back pressure’ if they are easing on the elevator from the first 50ft of the run rather than waiting until Vr before daring to move the controls.
I urge you to be wary of the POH when learning to fly. It is written by test pilots and concerns itself with the best way for other pilots to operate the aircraft. It does not concern itself with the best way to be taught how to fly. We instructors often tell half truths to get you around a problem. If your instructor is stuck with aircraft that shimmy and his boss won’t fix them then what can he do other than teach you to ‘fly around’ the problem.
I very much doubt he is teaching you something hazardous as he has got to send you off solo sometime and the last thing he wants to see is you staggering into the sky only to stall on takeoff and crash back to the ground.
Get used to the fact that all pilots have pet methods and particularly when it comes to instruction. Even in well standardised units such as RAF UAS squadrons there are differences. Certainly between airlines there are different ways of doing the same thing. There is a lot of science in aviation but some art does remain.
Your illustration of an aircraft struggling down the runway nose high and staggering into the air with the stall warner blaring is not really valid as I very very much doubt this is what your instructor is doing or telling you to do. It is perhaps what a PPL might do if he had heard about nose wheel shimmy techniques but had never been taught them… I remember a bold young PPL aged 17 who was told how to use the ADF by a mate of his. He got terribly lost and very scared a few weeks later when he tried to use it and got in a terrible muddle. I learned that lesson well and now never use a piece of kit or technique unless I have been explicitly taught it…
As for half inflated tyres that is dangerous.
Best of luck with your course. If I was your instructor I would be very impressed that you had read the POH – most thumb through it on day one and then use it as a convenient table leg leveller for the rest of their training!
WWW
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BIRCH & BRAMSON
FLIGHT BRIEFING FOR PILOTS-VOLUME 1.
Take off and climb-Undercarriage considerations.
Immediately directional control is ensured a GENTLE BACKPRESSURE must be applied on the control column to remove weight from the nosewheel.This important technique is sometimes overlooked so that the nosewheel is subject to unnecessary stress during the take off run.Furthermore under certain conditions there may occur a development called WHEEL-BARROWING.
If the situation is allowed to continue unchecked the aircraft can develop an uncontrollable swing leading to total loss of direction which is beyond correction.In the process the undercarriage has been known to collapse-can be corrected by moving back the wheel/stick SLIGHTLY to restore weight onto the mainwheels.
"Try as I might I can't find any mention of wheel-barrowing in my POH-therefore I can only conclude it does not exist and I have been teaching an incorrect technique for ten years"
FLIGHT BRIEFING FOR PILOTS-VOLUME 1.
Take off and climb-Undercarriage considerations.
Immediately directional control is ensured a GENTLE BACKPRESSURE must be applied on the control column to remove weight from the nosewheel.This important technique is sometimes overlooked so that the nosewheel is subject to unnecessary stress during the take off run.Furthermore under certain conditions there may occur a development called WHEEL-BARROWING.
If the situation is allowed to continue unchecked the aircraft can develop an uncontrollable swing leading to total loss of direction which is beyond correction.In the process the undercarriage has been known to collapse-can be corrected by moving back the wheel/stick SLIGHTLY to restore weight onto the mainwheels.
"Try as I might I can't find any mention of wheel-barrowing in my POH-therefore I can only conclude it does not exist and I have been teaching an incorrect technique for ten years"
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Two points here, firstly, all this scary stuff about nose high attitudes and wheelbarrowing and all that. Easy to control with a bit of practice really, only enough backpressure to bring the shimmy to a shiver. Braking, again balance braking and backpressure to reduce the shimmy. Dead easy really, just takes half a dozen t/o and landings in a flying school wreck to perfect.
Second point, is Hudson actually sugesting that maintenance is carried out on a flying school aircraft, nice idea, but I don't think it will catch on anywhere, its cheaper to teach students to counter the problems. Nothing like instrument and radio failures in real life situations you know !much more realistic than practice under controlled conditions !
Sorry,
Second point, is Hudson actually sugesting that maintenance is carried out on a flying school aircraft, nice idea, but I don't think it will catch on anywhere, its cheaper to teach students to counter the problems. Nothing like instrument and radio failures in real life situations you know !much more realistic than practice under controlled conditions !
Sorry,
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Yes, what is being talked about here is taking the weight off the nosewheel with a little back pressure, not raising it right up in the air. Also remember that the POH is often written for an American audience who generaly tend to fly of nice smooth tarmac. In the UK we are quite often operating from bumpy grass where this technique is definitely an advantage.
[This message has been edited by foxmoth (edited 06 January 2000).]
[This message has been edited by foxmoth (edited 06 January 2000).]
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From memory, I believe the weight off the nosewheel technique was first introduced by the RAF in early jet fighters. My Vampire Pilots'Notes AP 4099A, page 20 - Handling states : As soon as the aircraft reaches a speed of 60-70 knots IAS, lift the nosewheel just clear of the ground, then at 82-87 knots ease the aircraft off the ground.
I flew Vampires, and it was easy to get the nosewheel too high (especially at night)causing drag and a longer take off run. A recent accident to a warbird Venom in New Zealand which ran of the end of the runway, was put down to excessive nose high attitude in the early part of the take off. When it was obvious that the drag had affected the take off acceleration, the pilot aborted and got wet in the river.
It might be a coincidence, but the early De Havilland Comet airliners used the same technique, ie lift the nosewheel just clear of the runway as soon as the elevators were effective. De Havillands also designed the Vampire. Unfortunately there were two major accidents caused by this technique, resulting in loss of life. It was found that the pilots had over-rotated early in the run in order to get the nosewheel skimming the runway, and the aircraft simply failed to accelerate. Both Comets crashed off the end of the runway. Interesting that in modern times, the big jets leave the nosewheel on the runway until reaching the calculated VR speed for rotation.
I take the point that pilots would be banned from flying by some schools if they wrote a shimmy defect in the tech log. So you teach a techique that gets around nosewheel shimmy. What a dreadful reflection on General Aviation as a whole.
I maintain, however, that unless it is a rough field take off (the technique for which is covered in the manufacturer's POH), there is no reason to deliberately take the weight off the nosewheel during take off, until reaching the correct lift off speed. I certainly don't on Cessnas and Warriors et al, and have not experienced handling difficulties. On the other hand I have seen numerous examples of light aircraft getting airborne prematurely due to early back elevator.
If this the weight off the nosewheel technique was vital to the success of the take off, then it would be in the POH. This is notwithstanding the advice published in the book by Alan Bramston. He is entitled to his opinion. Certainly in the major airlines that I flew with, the manufacturer's recommended take off technique was accepted, and no personal techniques were allowed.
I flew Vampires, and it was easy to get the nosewheel too high (especially at night)causing drag and a longer take off run. A recent accident to a warbird Venom in New Zealand which ran of the end of the runway, was put down to excessive nose high attitude in the early part of the take off. When it was obvious that the drag had affected the take off acceleration, the pilot aborted and got wet in the river.
It might be a coincidence, but the early De Havilland Comet airliners used the same technique, ie lift the nosewheel just clear of the runway as soon as the elevators were effective. De Havillands also designed the Vampire. Unfortunately there were two major accidents caused by this technique, resulting in loss of life. It was found that the pilots had over-rotated early in the run in order to get the nosewheel skimming the runway, and the aircraft simply failed to accelerate. Both Comets crashed off the end of the runway. Interesting that in modern times, the big jets leave the nosewheel on the runway until reaching the calculated VR speed for rotation.
I take the point that pilots would be banned from flying by some schools if they wrote a shimmy defect in the tech log. So you teach a techique that gets around nosewheel shimmy. What a dreadful reflection on General Aviation as a whole.
I maintain, however, that unless it is a rough field take off (the technique for which is covered in the manufacturer's POH), there is no reason to deliberately take the weight off the nosewheel during take off, until reaching the correct lift off speed. I certainly don't on Cessnas and Warriors et al, and have not experienced handling difficulties. On the other hand I have seen numerous examples of light aircraft getting airborne prematurely due to early back elevator.
If this the weight off the nosewheel technique was vital to the success of the take off, then it would be in the POH. This is notwithstanding the advice published in the book by Alan Bramston. He is entitled to his opinion. Certainly in the major airlines that I flew with, the manufacturer's recommended take off technique was accepted, and no personal techniques were allowed.
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Hudson
I take it your just trying to stir up all of us instructors!
WWW is completely right 'Your instructor is teaching to to fly the plane not the POH'.
Yeah the POH has tips and advise of how to fly the aircraft but your instructor has invaluable experience which you can learn from - LISTEN TO IT.
When I taught on Cessnas shimmy was and still is a fact of life. Of course you tell the engineer (But you don't not fly -unless its realy bad or your personaly not happy with it) but quite often he'll spend a lot of time trying to fix the problem to no avail costing the flying school a fortune. In turn pushing up the cost of hiring the aircraft.
I take it your just trying to stir up all of us instructors!
WWW is completely right 'Your instructor is teaching to to fly the plane not the POH'.
Yeah the POH has tips and advise of how to fly the aircraft but your instructor has invaluable experience which you can learn from - LISTEN TO IT.
When I taught on Cessnas shimmy was and still is a fact of life. Of course you tell the engineer (But you don't not fly -unless its realy bad or your personaly not happy with it) but quite often he'll spend a lot of time trying to fix the problem to no avail costing the flying school a fortune. In turn pushing up the cost of hiring the aircraft.
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Having read this thread with some interest, I recall my instructing days in a PA-38.... where nose wheel shimmy was THE indication to relieve the pressure on the nosewheel.This had a two pronged effect...
1/ student then knew when to "apply back pressure" without having to "fix" on the instruments.
2/aircraft became more controllable on the take-off roll.(PA-38 screaming down runway with nose wheel shaking and bouncing is not the most controllable aircraft!!!)
With regards to the point about the P-Charts then becoming useless....don't they become less useful with every hour added to the aircraft?I mean...P-Charts are based on brand-new aircraft...not something 20 yrs old with dents in the wing etc!
If the strip you are flying into/out of is marginal, then surely the "short field take-off " technique should be applied!
P-Charts are not factored for STOL performance...ie. holding brakes on until full power is applied, which should give you an extra 3-4 % in take off distance available.
Surely also, the climb-out speed is supposed to be 1.3 x Vs.....which should give you a 30% higher airspeed than the stall!I am not aware of any aircraft that does not accelerate after becoming airborne(provided the nose is not raised excessively!)
CONCLUSION: take pressure off nosewheel...yes! raise nose....no!
May the number of landings you all do, equal the number of take-offs you do!
1/ student then knew when to "apply back pressure" without having to "fix" on the instruments.
2/aircraft became more controllable on the take-off roll.(PA-38 screaming down runway with nose wheel shaking and bouncing is not the most controllable aircraft!!!)
With regards to the point about the P-Charts then becoming useless....don't they become less useful with every hour added to the aircraft?I mean...P-Charts are based on brand-new aircraft...not something 20 yrs old with dents in the wing etc!
If the strip you are flying into/out of is marginal, then surely the "short field take-off " technique should be applied!
P-Charts are not factored for STOL performance...ie. holding brakes on until full power is applied, which should give you an extra 3-4 % in take off distance available.
Surely also, the climb-out speed is supposed to be 1.3 x Vs.....which should give you a 30% higher airspeed than the stall!I am not aware of any aircraft that does not accelerate after becoming airborne(provided the nose is not raised excessively!)
CONCLUSION: take pressure off nosewheel...yes! raise nose....no!
May the number of landings you all do, equal the number of take-offs you do!
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I must agree with Hudson. Spent many, perhaps too many, hours teaching in Cessna and Piper aircraft. Unless you are using roughfield techniques, where it is required, there is no need to raise the nosewheel of the ground. If shimmying is detected, certainly relieve the pressure on the nosewheel and unless its really bad, it will disappear, the shimmy not the wheel 
. raising the wheel of the ground on all takeoffs, not in my humble opinion.
. raising the wheel of the ground on all takeoffs, not in my humble opinion.
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Nosewheel shimmy is common has been common in light aircraft for decades. I fly brand new Cessnas everyday and nosewheel shimmy is a fact of life.
Shimmy dampers often become unserviceable because the weight is held on the nosewheel with forward pressure in the "Sprint & Snatch" technique.
The "weight off the nosewheel" technique actually prolongs the life of the shimmy dampers. It also makes for a very smooth take-off. You should listen to your instructor methinks.
Shimmy dampers often become unserviceable because the weight is held on the nosewheel with forward pressure in the "Sprint & Snatch" technique.
The "weight off the nosewheel" technique actually prolongs the life of the shimmy dampers. It also makes for a very smooth take-off. You should listen to your instructor methinks.
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Thanks for the varied advice. I did listen to my instructor. Turned out he was a brand new grade 3 with total, I repeat, total of 325 flying hours. That is why I had my doubts about his advice (or criticism, as it turned out) He is God to his students. He wears 3 gold bars, gold wings and a huge timepiece.
But do you know what? He had never read the Cessna 152 Manufacturer's Pilot Operating Handbook. All his info came from instructors on his PPL course. They were all junior instructors too.
It is not true to say that all training aircraft have built in nosewheel shimmy. The secret is regular maintenance. And the mechanics cannot fix a nosewheel shimmy unless the instructors and others tell the mechanic about the defect. And if the aforesaid gentlemen instructors lack the moral courage and the professionalism to write up the defect when it occurs, then the defect never gets fixed, does it?
So there you are. It is simple. IF the shimmy occurs, snag it. Then when it gets rectified, you won't have to take the weight off the nosewheel. Then you can learn to fly like the airline pilots who fly by their POH, and not by pet theories.
A wind up? Maybe -but it got you thinking, didn't it. Thats the beauty of Pprune...
But do you know what? He had never read the Cessna 152 Manufacturer's Pilot Operating Handbook. All his info came from instructors on his PPL course. They were all junior instructors too.
It is not true to say that all training aircraft have built in nosewheel shimmy. The secret is regular maintenance. And the mechanics cannot fix a nosewheel shimmy unless the instructors and others tell the mechanic about the defect. And if the aforesaid gentlemen instructors lack the moral courage and the professionalism to write up the defect when it occurs, then the defect never gets fixed, does it?
So there you are. It is simple. IF the shimmy occurs, snag it. Then when it gets rectified, you won't have to take the weight off the nosewheel. Then you can learn to fly like the airline pilots who fly by their POH, and not by pet theories.
A wind up? Maybe -but it got you thinking, didn't it. Thats the beauty of Pprune...
Guest
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Weight off the nosewheel, OK.
Vaild points re squawking shimmy too, if that's the only snag, be thankful.
Also be even more thankful you've not been in the States recently learning their short or worse soft field technique. Soft field technique in an Arrow is apply full flap, keep it rolling, don't stop at all, and apply FULL back pressure until it's only rolling on the mains, at which point, relax the back pressure and balance it with no weight (or contact) at all on the nose, then try to keep it in ground effect as it staggers off the ground at half a knot above the stall speed and as soggy as a piece of bog roll because of all that flap, and with the climb performance of a wet sponge.
Keeping it in ground effect is quite easy, it's not that keen on flying in the first place. Then it's just a case of retracting some of that flap while avoiding making contact with the ground again too soon!
Wheelbarrowing. The back pressure idea is relevant to some types, especially Piper twins, where it is all too easy to end up wheelbarrowing, as it's going to fly, almost regardless of elevator position, because of the angle it's at on the ground. So, if it's trimmed nose down for some stupid reason, it's *very* easy to end up with only the nose wheel in contact with the ground, and that's not at all desirable
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"Irish" Steve
Vaild points re squawking shimmy too, if that's the only snag, be thankful.
Also be even more thankful you've not been in the States recently learning their short or worse soft field technique. Soft field technique in an Arrow is apply full flap, keep it rolling, don't stop at all, and apply FULL back pressure until it's only rolling on the mains, at which point, relax the back pressure and balance it with no weight (or contact) at all on the nose, then try to keep it in ground effect as it staggers off the ground at half a knot above the stall speed and as soggy as a piece of bog roll because of all that flap, and with the climb performance of a wet sponge.
Keeping it in ground effect is quite easy, it's not that keen on flying in the first place. Then it's just a case of retracting some of that flap while avoiding making contact with the ground again too soon!
Wheelbarrowing. The back pressure idea is relevant to some types, especially Piper twins, where it is all too easy to end up wheelbarrowing, as it's going to fly, almost regardless of elevator position, because of the angle it's at on the ground. So, if it's trimmed nose down for some stupid reason, it's *very* easy to end up with only the nose wheel in contact with the ground, and that's not at all desirable
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"Irish" Steve
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Irish Steve. I am gobsmacked at your revelation of full flap take off in Pipers in the US. Looks like their FAA are pretty slack at not picking that gem up.
Re wheel-barrowing. I think the reason for that is that some instructors teach stick forward of neutral during cross-wind take off. This lifts the tail off the ground and in the worse case (which I have never struck, fortunately)the main wheels lose traction, and you then have a real directional problem. From observation, wheel barrowing occurs if the aircraft is not lifted off the deck at the correct speed.
With forward CofG (eg PA44/PA34 with 2 up front and no ballast) it is common to see lift off 10 knots faster than recommended by POH because of surprise at stick force needed to get it airborne.
Like it or not, sticking to POH speeds will prevent wheel barrowing.
Re wheel-barrowing. I think the reason for that is that some instructors teach stick forward of neutral during cross-wind take off. This lifts the tail off the ground and in the worse case (which I have never struck, fortunately)the main wheels lose traction, and you then have a real directional problem. From observation, wheel barrowing occurs if the aircraft is not lifted off the deck at the correct speed.
With forward CofG (eg PA44/PA34 with 2 up front and no ballast) it is common to see lift off 10 knots faster than recommended by POH because of surprise at stick force needed to get it airborne.
Like it or not, sticking to POH speeds will prevent wheel barrowing.