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3 point vs. wheel landing?

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Old 01-05-2014, 05:40 PM
  #26  
rowdyjoe
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Originally Posted by dbsonic
I've found that 3 point landings is not necessarily the best all around technique. The wheel landing provides the best overall control particularly in highly turbulent and crosswind conditions .. conditions under which you can do some real serious damage.
Exactly right. Windy and/or gusty conditions dictate more speed on approach and landing to provide full control even after touchdown. With a taildragger, a 3 point landing requires a slow approach and a full stall. The slower approach speed means less airflow over the control surfaces and results in reduced control response. In light winds, that's OK. However, you will find the airplane will balloon at or after touchdown if you are too fast.
A faster approach for a "wheel" landing allows more airflow over the control surfaces and much better control of the plane before and after touchdown. When flying a taildragger, keep the airplane straight with rudder until speed bleeds off and the tail settles on it's own, then pin the tail down with up elevator.
With tricycle gear airplanes in high or gusty winds, you need to keep your speed up on final and flair slightly less than normal. Touch down on the mains. Do not allow the nose gear to touch first or the airplane will "wheel barrow" and go out of control and probably break your prop.
In both cases, you need more speed on landing. Keep your "ground speed" up.

RJ
Old 01-05-2014, 05:45 PM
  #27  
Cpt Crash
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I notice that my aerobatic airplanes like 3 pointers. My MX2 and Giles 202 are also very happy with the tailwheel touching first, and then settling onto the mains as well. But my Monocoupe is a wheeler. It seems that a big factor is the symmetrical airfoil of aerobatic planes versus the flat bottom wing of the Coupe. If I fly the Coupe on a nice flat approach, when it reaches the runway it's nice and slow. I just let it settle onto the mains, back off the power, and keep my hands off the elevator. The Giles won't fly this attitude because it needs some AOA for its wing to fly slow.


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Old 01-05-2014, 06:49 PM
  #28  
rowdyjoe
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I've got the same issue with my GP Super Chipmunk 1.20. It would much rather touch down mains first than be forced into a 3 pointer. 3 pointers can be done but, you have to work at it more so than my Extra 300. I attributed it to the horizontal being mounted a bit higher than the wing ....similar to a Cap 232 but, not as pronounced. Or ...it could be me.

RJ
Old 01-05-2014, 08:12 PM
  #29  
husafreak
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Depends on the airplane as to whether a 3 point landing is even feasible, but I certainly do not agree that the ideal is to stall at the point you touch down, you never want to stall, especially close to the ground. This applies to full scale as well as models.
Old 01-05-2014, 08:31 PM
  #30  
rowdyjoe
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Originally Posted by husafreak
Depends on the airplane as to whether a 3 point landing is even feasible, but I certainly do not agree that the ideal is to stall at the point you touch down, you never want to stall, especially close to the ground. This applies to full scale as well as models.
You're dead wrong.
Old 01-05-2014, 10:08 PM
  #31  
sehlers
 
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Models and how you fly them can make a difference and your perception on landings can be also a factor . However in Full scale ,it can also be pilots choice with a given
aircraft . An acquaintance of mine that is a Senior Captain as a Heavy Equipment Driver ( read as Airline Pilot ) that also is a Advanced Aerobatics competitor ,told me
once on a flight we had in a rather nice GA plane he owned ( Luscombe 8E ) , when asked why he landed "3 Point " ,his answer was that the tail wheel has to come down ,
so why not at the time of landing . Of course this is with a so-called squirrely landing airplane that has had a ground looping stereo-type ,handed to it ,due to all the trouble
people had gotten into with this particular airplane over the years .I'm a licensed full scale pilot also and having flown my own Experimental Tail Drager airplane ,landing it can be very enlightening . The tail wheel design can also make or break a an airplane when it comes to full scale . When flying Full Scale tail draggers ,there are some lessons
learned that don't seem to make much difference on our R/C models ....
Old 01-05-2014, 10:42 PM
  #32  
TexasAirBoss
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Some of my airplanes seem to like to 3 point, and others seem to wheel land prettier. I just listen to the airplane and do what it likes.
Old 01-06-2014, 12:23 AM
  #33  
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on my Cub and "crop duster" (both tail draggers) i prefer wheel landings , vs three pointers on a calm day, it requires a little more work at it to get them to look just right...same thing with trike setups...

aerobatic planes like Extras and Yaks do 3 pointers easier than wheels landings, it probably has to due with the way i have them balanced

Last edited by MetallicaJunkie; 01-06-2014 at 12:28 AM.
Old 01-06-2014, 01:28 AM
  #34  
bogbeagle
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Imagine trying to 3-point this ... and getting it badly wrong, such that it bounces and you need power.

That could get quite sporty, I'd imagine.
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Old 01-06-2014, 01:30 AM
  #35  
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In most cases rate of decent is the undercarriage killer, not groundspeed.

A nice flair to touchdown is prefered but being able to put the mains down lightly and "fly" it along the ground at a higher speed is a good tool to have in your deadstick toolbox if you need it..
Old 01-06-2014, 04:24 AM
  #36  
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The largest factors on our models when it come to 3 pointing a landing or wheel landing is the overall weight and the AOA sitting on the gear, you can in fact have two of the exact same models with exception to weight and/or landing gear AOA differences and one will settle into a wheel landings better than the other, or 3 point better than the other. Other then that, practice, practice practice...

Bob
Old 01-06-2014, 05:08 AM
  #37  
alasdair
 
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Originally Posted by BMatthews
Consider too that full size aircraft have much higher stall angles of attack than the same design as a model. That old Reynolds number issue again. So if you want a model to be at the stall angle when in a flat 3 point attitude you need to flatten the angle. Models up to around 4 foot span will stall at around 7'ish degrees AoA. The big gas engine models of over 15 lbs and at 100 inch span and bigger will stall at a more full size angle of up around 10'ish degrees. Meanwhile the full size stall angles are likely up around 15 or more degrees. That's why we see airliners "gliding" in at around a 10 to 15 degree glide slope even with their nose well up in the air. For that size and at that sort of Reynolds number the stall angle is way up well over 15 degrees. We simply can't match that with our models.

So in the end if we can land a Spitfire or Mustang model of modest to medium wing span with a nice 3 point landing it's likely that we timed the stall to the landing "just so". The model was in the process of stopping and pitching down just as the wheels touched down. But a landing without this sort of well time aggressive stall for a model will need to be a rolling landing. We just can't NOT end up with a lot of bouncing otherwise other than by sheerest luck.
BMatthews is right about the different stall angles of models due to the lower Reynolds Number. I think he is right that a model of a taildragger (e.g. P-51 or Hurricane) will stall before the tailwheel touches, but if it is done correctly, an inch above the ground, the model will still settle neatly in a smooth looking landing.
Slapping a taildragger onto the ground at a speed way above its stalling speed will always result in a mighty bounce.

When learning to fly on a taildragger (Chipmunk) we always tried for a 3-pointer. The secret is speed control, and the secret to that is Trimming. Most model pilots approach too fast, and most do not retrim for a correct approach speed. They leave the trim set for high speed cruise (or even full throttle) and then fly the approach with a handful of up elevator. That is very hard to do accurately (and would earn a severe b*ll*cking from an instructor on full size).

BTW BMatthews, I am surprised that I have to correct your statement "That's why we see airliners "gliding" in at around a 10 to 15 degree glide slope even with their nose well up in the air."
Airliners ALWAYS approach at an angle of 3 degrees. ALL ILS glideslopes, and PAPIs and VASIs are set at 3 degrees. The reason the nose is well up in the air is because they have LE slats. Watch the traffic at a busy airport and you can spot airliners that use flaps (all of them) but no slats (very few) by the nose down sit in the air on approach.
Old 01-06-2014, 06:30 AM
  #38  
jerdavis
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FWIW: My scale T-6s require wheel landings as does my 1/5th P- 51. I suppose once in a while I could get away with a 3 pointer, but a full stall landing usually results in a bounce (no matter how small) that gives that moment of no control and a resultant ground loop and parts flying off of the airplane.

While struggling with the P51 landings I had a full scale pilot tell me to try wheel landings like he does his full scale P51…..I did and the ground looping problem ended.

I wheel land all of my warbirds. Using full flaps and a steep approach, I round out about 1 foot above the runway, chop the throttle, hold the airplanes attitude and let it settle on the ground by itself. Doesn't get any prettier or easier.

On the other hand, my stinger 120 will not wheel land with out bouncing and damage. Probably due to soft landing gear.

Jerry
Old 01-06-2014, 07:02 AM
  #39  
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Originally Posted by jerdavis
While struggling with the P51 landings I had a full scale pilot tell me to try wheel landings like he does his full scale P51…..I did and the ground looping problem ended. Jerry
Interesting. I have heard of full size taildraggers landing on the mains and gradually lowering the tail, but I thought it was to reduce runway occupancy - and the long zigzag taxy needed when the nose is in the way.
Did your full size P-51 pilot operate from tarmac?
Old 01-06-2014, 07:21 AM
  #40  
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who cares how you land as long as you dont bounce i flytrikes 90% ARE 3 POINT LANDINGS
Old 01-06-2014, 07:23 AM
  #41  
bogbeagle
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Originally Posted by [email protected]
who cares how you land as long as you dont bounce i flytrikes 90% ARE 3 POINT LANDINGS

Hold on, I'll fetch my popcorn for this.
Old 01-06-2014, 08:52 AM
  #42  
husafreak
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Originally Posted by rowdyjoe
You're dead wrong.

Stall away then bro! Let me know how that works out for you.
Old 01-06-2014, 09:51 AM
  #43  
vertical grimmace
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Originally Posted by husafreak
Stall away then bro! Let me know how that works out for you.
The maneuver that we call the landing, is a stall.
Old 01-06-2014, 12:56 PM
  #44  
rowdyjoe
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The bottom line is ...all winged aircraft must "stall" (ie. quit flying) to stay on the ground for landing. Taildragger or tricycle, they all must "stall" at some point during the landing procedure. Do it too high and you loose, or damage, your aircraft.
In windy conditions, it is advisable to "fly" (above stall speed) the airplane down to touchdown and allow speed to bleed off until it is below stall speed. After that, your tail or nose wheel with do the steering. Before that your rudder should do the steering.

Most RC pilots, to the detriment of their pocket books, don't have a clue about the theory of flight. As long as their airplane(s) goes up and down and round and round they are happy. Full scale pilots MUST care about it or they, and their passengers, will die.

If you want to learn the real answer, go here for an excellent explanation on the theory of flight ...http://en.wikipedia.org/wiki/Stall_%28flight%29
...or you can read "Stick and Rudder" by Wolfgang Langewiesche. IMO, no other book explains it better.

RJ
FAA Commercial ASMEL
Old 01-06-2014, 01:01 PM
  #45  
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Originally Posted by alasdair
.......
BTW BMatthews, I am surprised that I have to correct your statement "That's why we see airliners "gliding" in at around a 10 to 15 degree glide slope even with their nose well up in the air."
Airliners ALWAYS approach at an angle of 3 degrees. ALL ILS glideslopes, and PAPIs and VASIs are set at 3 degrees. The reason the nose is well up in the air is because they have LE slats. Watch the traffic at a busy airport and you can spot airliners that use flaps (all of them) but no slats (very few) by the nose down sit in the air on approach.
I'm thinking more about the last few hundred feet of descent to touchdown. Not so much about the approach glide slope. Where, as you say, the flight path is constrained to set values to make everyone fly the same way. Watching any number of videos of airliners landing and the last few hundred feet to touchdown can show a rather surprisingly high angle of attack when we consider the airfoil chord line to the path traveled by the airplane.
Old 01-06-2014, 01:02 PM
  #46  
rowdyjoe
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Originally Posted by husafreak
Stall away then bro! Let me know how that works out for you.
....and you continue in your ignorance and I hope it works for you but, don't post it on a public forum where someone may take it as truth.
Old 01-06-2014, 04:15 PM
  #47  
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Originally Posted by alasdair
Interesting. I have heard of full size taildraggers landing on the mains and gradually lowering the tail, but I thought it was to reduce runway occupancy - and the long zigzag taxy needed when the nose is in the way.
Did your full size P-51 pilot operate from tarmac?

Sorry..didn't mean to convey that I was a full scale P51 pilot. I'm a 1/5th scale P51 pilot.

Jerry
Old 01-06-2014, 08:19 PM
  #48  
bogbeagle
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Well, it's a simple task to land an aeroplane, without bringing the wing very close to the stalling angle of attack.


oneaw@msn does it all the time, when he "3-points" his trikes.


I do it when I wheel-on my tail-draggers.


If my aeroplane was very close to the stall, I would have little-to-no control over it.

Last edited by bogbeagle; 01-06-2014 at 11:56 PM.
Old 01-06-2014, 11:35 PM
  #49  
husafreak
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I should probably just let this go but i think there is some misunderstanding. I said I do not think stalling the airplane onto the ground is a good goal for landing. Then someone tells me I am dead wrong to say that. Then I look back into the thread and see this person has said that same thing himself. So there must be some misunderstanding. But to be told I have no business posting on a public forum is insulting. Please do not be so quick to attack other forum members, even if you consider yourself to be some kind of ultimate expert.
Old 01-07-2014, 02:22 AM
  #50  
alasdair
 
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I apologise for going off-topic a bit, but trikes are never stalled on landing. Airliners are landed by flying a 3 degree approach right down to the runway, then for the flare you close the throttles and check back on the stick (the order and timing vary with type) to raise the nose and reduce rate of descent at which the main gear hits the runway, then gently lower the nose gear. You don't *****foot around trying for a greaser, because you need weight on the mains before you can pull reverse, and you need the nose down before you can use the brakes.

So, when the main gear hits the runway, on a trike the aircraft's inertia with the CG ahead of the wheels makes it want to pitch nose down - which is OK.

On a taildragger the CG is aft of the wheels so when the wheels touch -unless it is very gentle - the aircraft's inertia makes it pitch nose up, which is a bounce. For this reason I think good wheeler landings on a taildragger are probably more difficult than 3 pointers.


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