Conventional gear take-off techniques...
Sun May 21, 2006 12:07 pm
I have found one of those conflicts of opinion in flying techniques that I thought people here might find interesting. I am seeking the opinions of those who fly tailwheel, hopefully with more than 500 hours.
When flying the L-5, in calm or headwind conditions, I have been taught to bring the tail off the ground as soon as possible (push the stick forward). In a recent discussion with a very experienced tailwheel pilot, he was aghast that I was doing that, and felt that I should roll it as far as I could on the tailwheel before allowing the tail to come up on its own accord. The price of 8.00 SC tailwheel tires aside, what is the opinion of those who fly tailwheel- should you leave the tail on the ground, and let it come up by itself, or push the stick forward to get it up as soon as possible? I have my own opinion but would like to see what more experienced people have to say about this.
When flying the L-5, in calm or headwind conditions, I have been taught to bring the tail off the ground as soon as possible (push the stick forward). In a recent discussion with a very experienced tailwheel pilot, he was aghast that I was doing that, and felt that I should roll it as far as I could on the tailwheel before allowing the tail to come up on its own accord. The price of 8.00 SC tailwheel tires aside, what is the opinion of those who fly tailwheel- should you leave the tail on the ground, and let it come up by itself, or push the stick forward to get it up as soon as possible? I have my own opinion but would like to see what more experienced people have to say about this.
Sun May 21, 2006 12:22 pm
I try to get the tail in the air as soon as possible, primarily to have rudder control authority. The tail won't come up until you get enough airspeed anyway. All that tailwheel's purpose in life is to do is to keep the rudder out of the dirt.
Sun May 21, 2006 12:24 pm
I was taught tail wheel flying like you it seems. I always get the tail up as soon as possible so I can see where I'm heading into. But also, I want to reduce weight on the tail wheel to avoid shimmy.
I guess that the reason to keep the tail on the ground for as long as possible is to maintain better control on the runway. Visibility is not that much needed, as my Dad says about flying the Harvard, when the tail is low, as long as you don't see the runway you are doing fine. Start seeing it, you have veered of course!
I guess that the reason to keep the tail on the ground for as long as possible is to maintain better control on the runway. Visibility is not that much needed, as my Dad says about flying the Harvard, when the tail is low, as long as you don't see the runway you are doing fine. Start seeing it, you have veered of course!
Tailwheel 2p
Sun May 21, 2006 12:55 pm
The problem with forcing the tail up is it brings all kinds of airframe torque and prop gyroscopics into play nearly simultaneously. With low-power aircraft it's not that big a deal. When you start moving into higher power aircraft, you can get yourself into trouble very quickly.
The prime culprits (my 2p, anyway) are A: torque due to rotating slipstream; B: torque due to P-factor (asymetric prop loading); and C: torque from the gyroscopic effect of the prop rotation.
These factors are in play during various parts of the takeoff run.
A: Torque from the rotating slipstream stabilizes when the engine reaches full power (or whatever you use for takeoff power).
B: P-factor comes into play as the tail comes up and then disappears. It reappears again at lift off. Picture this in play everytime a change in attitude occurs.
C: Torque due to gyroscopic precession of the prop is only present during the time the tail is raised. It is directly related to the speed at which the tail is raised. Tail up slowly and the toque effect comes on slowly. Raise the tail quickly and the onset is amplified and occurs in a smaller period of time.
"A" occurs at the beginning of the takeoff run and stabilizes at takeoff power. "B" and "C" both come into play during while the tail is coming up and is very noticable in higher powered aircraft. It's here that you can conceivably run out of rudder to counteract the torque.
The prime culprits (my 2p, anyway) are A: torque due to rotating slipstream; B: torque due to P-factor (asymetric prop loading); and C: torque from the gyroscopic effect of the prop rotation.
These factors are in play during various parts of the takeoff run.
A: Torque from the rotating slipstream stabilizes when the engine reaches full power (or whatever you use for takeoff power).
B: P-factor comes into play as the tail comes up and then disappears. It reappears again at lift off. Picture this in play everytime a change in attitude occurs.
C: Torque due to gyroscopic precession of the prop is only present during the time the tail is raised. It is directly related to the speed at which the tail is raised. Tail up slowly and the toque effect comes on slowly. Raise the tail quickly and the onset is amplified and occurs in a smaller period of time.
"A" occurs at the beginning of the takeoff run and stabilizes at takeoff power. "B" and "C" both come into play during while the tail is coming up and is very noticable in higher powered aircraft. It's here that you can conceivably run out of rudder to counteract the torque.
Sun May 21, 2006 2:56 pm
In the small A/C like the J-3, I push the stick forward to get the tail up and its helps shorten the ground roll. In the bigger iron, in my short time, learned that the tail is off the ground when it is ready, but kept low to insure you have rudder authority. It just does't get any better than a tail wheel A/C
Cheers,
Lynn
Cheers,
Lynn
Sun May 21, 2006 6:05 pm
If you were supposed to pick the tail up right away wouldn't it have had a nose wheel instead of a tailwheel?
As L2Driver pointed out it can cause other problems. I listen to people all the time complaining about running out of right rudder on take off and it amazes me! That's mainly a self induced problem by pushing foreword on the stick, it's very seldom caused by using too much power. When you force the tail up the airplane turns left, it's as simple as that.
It's a common problem with pilots that learned to fly with tricycle gear.
When you think about it, most tricycle gear pilots and instructors hold full up elevator while on the take off roll so why do they want to use full down elevator when in a conventional gear airplane?
Glenn
As L2Driver pointed out it can cause other problems. I listen to people all the time complaining about running out of right rudder on take off and it amazes me! That's mainly a self induced problem by pushing foreword on the stick, it's very seldom caused by using too much power. When you force the tail up the airplane turns left, it's as simple as that.
It's a common problem with pilots that learned to fly with tricycle gear.
When you think about it, most tricycle gear pilots and instructors hold full up elevator while on the take off roll so why do they want to use full down elevator when in a conventional gear airplane?
Glenn
Conventional gear takeoffs
Sun May 21, 2006 6:59 pm
I have a significant amount of both low, medium and high-powered tail-wheel time and some L-5 time and would not suggest your technique. Let the tail come up on its on and then you are most likely to have full rudder control for directional control before lift off. Popping the tail up early in many tail-wheel aircraft will get you a quick trip off the runway, especially in good cross-winds. It has happened in L-5s in strong cross-winds. Learning to look off to the side of the nose in a tail-wheel aircraft to judge your alignment with the runway and directional control on both takeoff and landing is something that isn't natural but is required to be proficient, in my opinion. As always, just my 2 cents.
Randy
Randy
Sun May 21, 2006 6:59 pm
Glenn Wegman wrote:
When you think about it, most tricycle gear pilots and instructors hold full up elevator while on the take off roll so why do they want to use full down elevator when in a conventional gear airplane?
Glenn
I never hold full up elevator in tricycle gear a/c on the take off roll. (Except maybe while doing a soft field takeoff procedure)
Do not recall being taught that either.
In our Skybolt, ( locking free castoring TW) I was taught to hold full back stick ( locked the TW) until full rudder authority. Hold her straight with the brakes and locked TW. Once the rudder was up ease the stick to neutral/slight nose down. Wait for the TW to come up and let her fly off the runway.
Last edited by oscardeuce on Sun May 21, 2006 7:22 pm, edited 1 time in total.
Sun May 21, 2006 7:11 pm
Whoa, loads of good advice reading you gentlemen. I'll keep that in mind next time I take the 185 up.
I never learned to hold full up elevators in nose wheel aircraft too, unless I'm performing a soft-field takeoff where you want the weight off the nosewheel.
I never learned to hold full up elevators in nose wheel aircraft too, unless I'm performing a soft-field takeoff where you want the weight off the nosewheel.
Sun May 21, 2006 8:23 pm
As others have said it depends on the airplane.
In the Cub I push the stick forward and get the tail up ASAP. In fact I taxi with the tail up, most of the time (tail wheels are expensive).
In the Sea Fury if you "pick it green", or rather if you pick the tail up early the nose will definately swing left (or right, if you're British). I keep neutral stick and follow the tail when it's ready to come up, then I add more forward pressure, to pin her level on the mains. Landing is just the opposite...keep the tail up until it's ready to come down (retracting the flaps on rollout speeds the tail coming down), then follow it and pin it at the bottom.
In the Cub I push the stick forward and get the tail up ASAP. In fact I taxi with the tail up, most of the time (tail wheels are expensive).
In the Sea Fury if you "pick it green", or rather if you pick the tail up early the nose will definately swing left (or right, if you're British). I keep neutral stick and follow the tail when it's ready to come up, then I add more forward pressure, to pin her level on the mains. Landing is just the opposite...keep the tail up until it's ready to come down (retracting the flaps on rollout speeds the tail coming down), then follow it and pin it at the bottom.
Sun May 21, 2006 8:52 pm
Hello Steve,
Your pumping Avgas through a 3350 and your concerned with the cost of Cub tailwheels!!
Glenn
Your pumping Avgas through a 3350 and your concerned with the cost of Cub tailwheels!!
Glenn
Sun May 21, 2006 9:52 pm
My preferred technique for Stearman/C-195 on down is to set the trim to the takeoff position and let 'er fly off when she's ready. The designers and test pilots set that position for a reason.
Stock Stearmans do great soft field takeoffs with the stick all the way back to the stop until the mains leave first.
Never worn out a tailwheel tire yet, but I intend to when my T-6 is flying.
Stock Stearmans do great soft field takeoffs with the stick all the way back to the stop until the mains leave first.
Never worn out a tailwheel tire yet, but I intend to when my T-6 is flying.
Many thanks
Sun May 21, 2006 11:10 pm
...I am very appreciative to those who have lent their experience to my question. I have felt that my instructor was wrong on this one but being a low time pilot in the face of 7000 plus hours is a bit intimidating. I have gone left on two occasions and ran out of rudder to correct. Both times were in crosswind where I brought up my tail ASAP. I won't be doing that any more...
Mon May 22, 2006 4:31 am
I generally raise the tail at the begining of the takeoff roll to get the aircraft in a more streamlined attitude for better acceleration, unless the aircraft in question has enough power to accelerate well in a three-point attitude. In low power aircraft this also prevents the aircraft coming off in an attitude that slows acceleration and climb. It is common to see inexperienced pilots getting the tail too high, frequently level, allowing the aircraft to accelerate in a tail low, climb attitude will allow it to fly off when it's ready.
Many instructors teach full forward elevator at the begining of the takeoff, while not the best technique, see above, it usually works fine in low power conventional gear aircraft that don't have powerfull elevators, in a J-3, under the right loading that will raise the tail before the rudder becomes effective, likewise in every Stinson (75/105/108) that I've flown. While I've never flow a L-5 I suspect it too has a very powerfull elevator, and I suspect your instructor is teaching a technique he has used succesfully in other aircraft but may be new to the Stinson series and unaware of the powerful elevators.
I looked at you L-5 at Horn Point, nice, quite authentic............except for the Ty-raps.
Tom-
Many instructors teach full forward elevator at the begining of the takeoff, while not the best technique, see above, it usually works fine in low power conventional gear aircraft that don't have powerfull elevators, in a J-3, under the right loading that will raise the tail before the rudder becomes effective, likewise in every Stinson (75/105/108) that I've flown. While I've never flow a L-5 I suspect it too has a very powerfull elevator, and I suspect your instructor is teaching a technique he has used succesfully in other aircraft but may be new to the Stinson series and unaware of the powerful elevators.
I looked at you L-5 at Horn Point, nice, quite authentic............except for the Ty-raps.
Tom-
Mon May 22, 2006 9:40 am
After 35 years of TW acft I developed a technique that basicly will work for all TW acft. Leave the TW down untill it's ready as there will be more control if needed. If you do it the same way all the time in all acft there is less chance of messing up when you go to a different acft. Cubs and Champs don't develop the torque to get you into problems but why do something different. I have watched two people roll their 985 Stearman's up in a ball on T.O. because they wanted to get the tail up so they could see with a slight left crosswind and the result was a nice left goundloop on takeoff and a wrecked acft. A stocker it isn't much of a problem but anything can be agrivated. In the Mustang I guarentee you will see the left side of the runway or worse at 50 in man/pres or more, with or without a crosswind, if you bring it up too fast.
good luck and have fun
good luck and have fun