Flying the Tecnam P92 Echo and Old Wives Tales
How many flying schools teach takeoff with 10 deg of flap in a 172 these days on a bitumen runway? I’d tip many. Years of experience tells instructors and pilots about what works well and what is safest. The dinosaur aircraft manufacturers need to get off their butts and update their POH’s with the 21 century. Golly, if I climbed my aircraft at the recommended speed, I’d have cooked 20 engines by now!
For the purposes of this discussion there is a big difference between reducing pressure on the nose-wheel and keeping it 2 inches off the ground.
For the purposes of this discussion there is a big difference between reducing pressure on the nose-wheel and keeping it 2 inches off the ground.
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I don't think this is a case of ignoring the POH. It is just applying a slightly modified technique to unload stress on the flimsy nosewheel for a soft field takeoff.
As said earlier this is different than keeping it off the ground.
The POH of the Tecnam P2002JF I did my initial training on doesn't include anything on takeoff technique(just checked). Neither for paved, soft or short field. Nothing on rolling start for a soft field or full brake full power build up for a short field. And it doesn't describe how to adjust for crosswind either. These are topics for a training manual. Not the POH which describes only the limits and performance.
Just a matter of having the schools write a proper training manual, the authorities verifying the manual and the school making sure the instructors follow the manual.
As said earlier this is different than keeping it off the ground.
The POH of the Tecnam P2002JF I did my initial training on doesn't include anything on takeoff technique(just checked). Neither for paved, soft or short field. Nothing on rolling start for a soft field or full brake full power build up for a short field. And it doesn't describe how to adjust for crosswind either. These are topics for a training manual. Not the POH which describes only the limits and performance.
Just a matter of having the schools write a proper training manual, the authorities verifying the manual and the school making sure the instructors follow the manual.
How many flying schools teach takeoff with 10 deg of flap in a 172 these days on a bitumen runway?
I say follow the POH, no one has ever shown me personally a POH procedure that makes me feel like if I do that I'm going to kill myself...
That which the test pilot has shown is "safe", and the manufacturer is happy is "the best performance this aircraft can show" is not necessarily the easiest way to fly, the softest landing nor the best engine cooling/gear & brake life etc. etc.
... or nose wheel life, for that matter, to bring it back to the thread - if you are flying a type with a particularly fragile nose wheel on unprepared surfaces.
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Frankly, it’d be short-sighted to not consider the Lawyers’ scrutiny of and input to any POH, in an effort to limit the airframe manufacturers exposure to litigation. You can Bet the lawyers ain’t Test Pilots either... and I reckon it’d be a fairly safe bet they wouldn’t give a toss about modifying a test pilots input either.
You don’t have to be ancient old to remember the near-death of GA Manufacturing in the USA as a consequence of ambulance-chasing, litigious lawyers.
You don’t have to be ancient old to remember the near-death of GA Manufacturing in the USA as a consequence of ambulance-chasing, litigious lawyers.
Judging by the comments so far, it seems the consensus is that early nose wheel lifting is a good thing regardless of the pros and cons. Maybe the majority of readers who elect not to post feel the same. That said, it must be confusing for new students (or even laid-off former airline pilots returning to general aviation) to be told by an occasional instructor to forget the POH, just do as I say and everything will be alright.
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Just stick to with what the manufacturer said. There is no need to reinvent the wheel. Still many airlines try to do this.
The POH has a recommended technique.
Nothing stating you can’t excercise a little bit extra mechanical sympathy.
Even though Cessna initially called their tricycle gear the “Landamatic” the nose wheel is really just there to support the weight.
Just for giggles next time you preflight a light single engine airplane see how much you can pull the yoke or stick back for the elevator to be neutral.
Mark it with a bit of sticky tape on the push/pull tube.
You’ll be surprised how much sooner the airplane levitates off the runway.
There is barely any need to “rotate” a light airplane.
The airplane doesn’t fly because it has an airspeed indicator.
Nothing stating you can’t excercise a little bit extra mechanical sympathy.
Even though Cessna initially called their tricycle gear the “Landamatic” the nose wheel is really just there to support the weight.
Just for giggles next time you preflight a light single engine airplane see how much you can pull the yoke or stick back for the elevator to be neutral.
Mark it with a bit of sticky tape on the push/pull tube.
You’ll be surprised how much sooner the airplane levitates off the runway.
There is barely any need to “rotate” a light airplane.
The airplane doesn’t fly because it has an airspeed indicator.
You can do soft field or short field procedures if needed. There is no need to teach people to force hovering in ground effect at speeds too low for flying.
Pilots are funny creatures when it comes to figuring things out for themselves, I had a guy who swore black and blue that leaving the cowls open on a 207 made it fly faster all because one day he forgot to close them, when he did, checked the GPS and saw he was going slower!! then opened them and a little while later was going faster, he never even considered that the winds simply changed a couple of knots and that the laws of physics were completely against what he was trying to tell me. I suspect a lot of these OWTs start this way, someone pulled back on the stick a little sooner than usual one day, got the wheel "A couple of inches off the ground" (no way to actually tell this) and it leapt off the ground way faster so they started doing it from then on, they didn't even consider a gust of wind or a change in wind direction was what caused it, perhaps even some kind of wind shielding was occurring from buildings or any other number of things. What scares me about this sort of thing is that they might teach this to someone who'll jump into something like a 210 one day where they'll try this exact technique and then wonder why it never accelerated and coasted off the end of the runway into the trees, "But sir, I had the wheels exactly 2 inches off the ground just like I was taught by bob! What do you mean witnesses saw the wheel hanging a foot off the runway, I'm sure it was only 2 inches!"
Where did anyone say that the aircraft will take off faster by raising the nose wheel?
Using the proper technique the take off distance ground roll is least with a soft field take off.
Lifting off in ground effect however and care must be taken to accelerate prior to climbing out of ground effect.
There is an inference above that lifting the nosewheel off early, is a way to make the aircraft takeoff faster, be it into ground effect or shortened takeoff roll, but that was never part
of the discussion. As a result, it could be suggested that I for one who use this technique, am doing it for a shorter takeoff and this is completely incorrect.
I’ve never heard of anyone lifting the nose off early from the start, doing it for the purposes of a shorter or faster takeoff.
I've flown about 40 different types of LSA. Centaurus is correct. On tarmac, leaving the nosewheel on the ground with just a hint of back pressure on the stick/yoke is the safest and most efficient course of action. It will also produce the shortest ground roll (less induced drag).
Markkal I think you mean 'Alpha'. Incidence is fixed (unless you're a retired F-8 driver).
Markkal I think you mean 'Alpha'. Incidence is fixed (unless you're a retired F-8 driver).
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Markkal I think you mean 'Alpha'. Incidence is fixed (unless you're a retired F-8 driver).[/QUOTE]
I wish I was a retired F-8 driver !!!!!
Yes right wing angle incidence is fixed vis a vis fuselage, angle between wing chord line and longitudinal axis
But not towards the airflow (AoA)
AoA (And If I understand correctly Alpha) varies from Minus few degrees in cambered wings (Zero lift) / 0 degrees in non cambered symmetrical wings -Aerobatic high performance singles symmetrical not cambered no incidence no dihedral- to around 18 degrees ( Stall).
And you nail the point about easing the nosewheel ( or tailwheel) to reduce drag and obtain the shortest T.O. run. But NOT from the start as it will have the opposite effect, only when speed builds up to generate enough lift,
I am also a mountain rated pilot in france, and this technique is used to operate from grass short fields T.O. run.
It is absolutely vital, given the density altitude and diminished performance of already underpowered piston singles.
We also ad a touch of flaps for a second to help with creating lift as soon as speed builds up to additionally ease the mains off the ground an accelerate in ground effect with a touch of forward stick speed -and lift- builds up quickly.
Perhaps beyond the scope of this thread, but it shows that we have a precious tool to reduce drag in our trainers, lacking in power...
I wish I was a retired F-8 driver !!!!!
Yes right wing angle incidence is fixed vis a vis fuselage, angle between wing chord line and longitudinal axis
But not towards the airflow (AoA)
AoA (And If I understand correctly Alpha) varies from Minus few degrees in cambered wings (Zero lift) / 0 degrees in non cambered symmetrical wings -Aerobatic high performance singles symmetrical not cambered no incidence no dihedral- to around 18 degrees ( Stall).
And you nail the point about easing the nosewheel ( or tailwheel) to reduce drag and obtain the shortest T.O. run. But NOT from the start as it will have the opposite effect, only when speed builds up to generate enough lift,
I am also a mountain rated pilot in france, and this technique is used to operate from grass short fields T.O. run.
It is absolutely vital, given the density altitude and diminished performance of already underpowered piston singles.
We also ad a touch of flaps for a second to help with creating lift as soon as speed builds up to additionally ease the mains off the ground an accelerate in ground effect with a touch of forward stick speed -and lift- builds up quickly.
Perhaps beyond the scope of this thread, but it shows that we have a precious tool to reduce drag in our trainers, lacking in power...
Last edited by markkal; 29th Apr 2021 at 08:17.
Alpha is controlled by the elevator and can easily be greater than 20 degrees in a snap/flick roll. The wing just isn't generating any lift. Operating from soft and/or short fields is - as you clearly know Markkal -very different from a smooth tarmac runway. On tarmac, leaving the nosewheel on the ground is the safest and most efficient course of action.
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Alpha is controlled by the elevator and can easily be greater than 20 degrees in a snap/flick roll. The wing just isn't generating any lift. Operating from soft and/or short fields is - as you clearly know Markkal -very different from a smooth tarmac runway. On tarmac, leaving the nosewheel on the ground is the safest and most efficient course of action.
I also concur leaving the nosewhel on the ground is te safest way to go on concrete, but start to ease it off at a shallow angle at POH rotation speed is the way to go, not to pull it off the ground 20 knots faster, that is something I see every day; Tendency to take off fast and land fast....
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Definitely out of topic, and I was referring to snap roll (Accelerated stall + roll by rudder input) the purpose is to stall the wing abruptly by a sharp input of back stick at a speed well below VA ( And to play safe well below max flight manual allowed flick speed limits) thought don't know how many degrees that would be Though for those interested in numbers its VS x square root of G load, the wing will stall at a given speed and Gload exerted.
I've always believed the received wisdom that the average GA aerofoil 'stalls' at around 17 degrees alpha. The fact that it may still be generating some lift is irrelevant if the lift generated isn't enough to support the weight of the aeroplane, wouldn't you agree?
Totally agree Markkal. Taking off and landing either too fast or too slow is not good practice! To return to the original point;- the idea that - on smooth tarmac - raising the nose wheel is productive is complete bollocks. In fact, its counter-productive. The ground roll is extended and directional control reduced. These aren't my opinions, they're observable facts.
Totally agree Markkal. Taking off and landing either too fast or too slow is not good practice! To return to the original point;- the idea that - on smooth tarmac - raising the nose wheel is productive is complete bollocks. In fact, its counter-productive. The ground roll is extended and directional control reduced. These aren't my opinions, they're observable facts.