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landing bounce

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landing bounce

Old 09-16-2012, 05:08 AM
  #51  
jester_s1
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Default RE: landing bounce

That's a really common beginner error to come in too hot. They are scared the plane is going to drop out of the sky or get hit by a wind gust so they try to keep some safety margin. I did that too for way too long. What cured me was getting out on a gentle wind day and really experimenting with shooting approaches just a foot off the ground. My plane would keep flying at a much slower speed than I had thought it would, which gave me the confidence to slow it down on approaches. I also learned that day how to hold flare and set it down with the throttle. Learning to skim the ground with the plane just 1-2 mph above its stall speed is crucial to making good landings.
Old 09-16-2012, 05:12 AM
  #52  
rmh
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Default RE: landing bounce

The classic "chop n drop" approach will get a bounce every time and remove the gear on many of the little ARFS
Old 09-16-2012, 05:46 AM
  #53  
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Default RE: landing bounce

Approach speed is always a factor. Learning his plane's characteristics and "personality" is something he needs to work through. There's no substitute for that, not even when using the expensive flight simulators. The eye-plane-thumb-radio connection is complicated, until it falls into place in your head. After that, it just gets tighter, and tighter.

When you spend time with him again, try and reassure him that the ground isn't something to fear, and that you have to head for it at least once every flight, so he'd better get used to that! It's also really important that he improves his handling capabilities when the plane is coming toward him. Teach him the hard-and-fast rules, like: "Coming toward you, the low wing gets the stick for correction," and all the usual stuff. Trying to put himself in the cockpit means his responses will be too slow should a wingtip drop near the ground.

Sounds like you're well on your way to hashing it out. Odds are, it's just the normal newbie stuff.

~ Jim ~
Old 09-16-2012, 06:53 AM
  #54  
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Default RE: landing bounce

his flying technique. I mentioned in post #5 that he tends to land long, usually in the last third of the runway. Our runway is 600+ feet with the pilot stations at mid point. The plane thus glides past his position and is going away from him. He can see that he is running out of runway and therefore may be anxious and forces the plane down which may cause the bounces
Well for normal sport flying he should just throttle up and go around for another attempt.

I used to race Formula One which were heavy, low drag tai- dragger models that you landed dead stick so there was only one shot at landing. Coming down from 175 mph to landing speeds (25-30 mph) took about 1/4 to 3/8ths a mile to lose speed, often after a minute of high adrenaline flight. So landings were usually tense when the runway was under 600 feet. The technique that worked well was to get the wheels on the ground regardless of speed. If slow enough, just wait out for the tail to drop.

But on those hot landing that were going way too fast and long, we found that shoving down elevator would lift the tail so that the wing would scrub off the energy while gluing the wheels to the runway. After losing the speed, you go back to normal control inputs.
Old 09-16-2012, 07:18 AM
  #55  
da Rock
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Default RE: landing bounce

What's the real lesson to learn in this thread about aerodynamics?

Very often, it ain't an aerodynamic problem at all.
Old 09-16-2012, 08:31 AM
  #56  
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Default RE: landing bounce

Truer words was never spoke.

~ Jim ~
Old 09-16-2012, 10:10 AM
  #57  
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Default RE: landing bounce

LOL, Took my Eflite T-34 out for some flights in my backyard. I converted this to glow with a Magnum 52 FS. This plane is a PITA to land. You have to grease it in, if you stall it in, it slams to the ground. I dont have a lot of room to land it, and a fence at both ends, so I have to clear the fence before I can land. Tried it with flaps, pitches up and stalls out, or climbs with a little throttle. Need to play with the flap adjustment for landings, takeoffs use full flaps, landings about 1/3 of that.  When I get the speed just right for it to land properly it goes long. If I didnt have that fence to contend with, I could get it to land good every time, but man what a PITA on short runways.   Now I can land my Kadet LT40 in the same space with room to spare, and except for the bumpy ground, looks good when it lands.

This may be the last flights on the plane though, A 13 MPH crosswind kicked up when trying to bring it in for a landing and it yawed it towards me, and I didnt have the speed to bank away and couldnt get enough speed up to climb and flew it into a tree. Plane is OK, the nose gear wire popped out and a servo arm snapped off, and lost the link, but the plane is fine.  I have never really liked this plane like I thought I would.  So going to fix the servo arm and give it one more try without the droops and see if it makes a difference and if not, going to strip the goods out of it for a different plane.   I resolved the long takeoff, now it takes off in a short distance, but this plane has always been a pain to land.

I never bounced it though!  It almost always hits nose first when it lands, unless I land it hot. I just dont have enough runway to do that.
Old 09-16-2012, 10:35 AM
  #58  
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Default RE: landing bounce

Yeah. Landing it right on the nose definitely stops that "bounce" problem! Leaves you with a few others, though, I'd reckon!

You might (just a suggestion here) want to find a slightly larger area to fly and land it?

Sounds like you're having fun, though.

~ Jim ~
Old 09-16-2012, 11:44 AM
  #59  
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Default RE: landing bounce



My 2 cents.

Anyone consider that maybe its an engine thrust problem e.g. No downthrust or possibly up thrust on the engine?

I have a Kaos that had two much down thrust (4 degrees down) and it stuck to the landing strip like glue until I applied up elevator at which point it would pop into the air. In this case I was thinking the opposite that it the thrust wasatzero or up instead of down andthat this could be causing the bounce. The only other thing I could think of would be too much positive incidence on the wing.




Old 09-16-2012, 12:48 PM
  #60  
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Default RE: landing bounce

I'll be curious to see what they find out. I'll guess it's newbie stuff.

~ Jim ~
Old 09-16-2012, 01:46 PM
  #61  
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Default RE: landing bounce

All depends on if its an ARF or Kit.   If an ARF, the thrust angles are pretty much dialed in for most engines. Kits can be off depending on how it was built.   I am adding a couple degrees right thrust to my 4*120 because the DLE20 has it yawing left.

Texas, I have a place I fly on Tuesday evenings that has more room, and once the corn is cut down, the landings will be much easier.  The weather has been bad the past week and doesn't look good for this week either and needed to get some flying in. I have park flyer room but park flyers and wind dont mix.  I am considering getting another 4*, a 40 size to put the Magnum 52 on. I can fly the 120 here, but dont want to take a chance on a bad landing, which if history shows, means landing on the fence, which would not bode well for the plane.
Old 09-16-2012, 03:05 PM
  #62  
Microz
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Default RE: landing bounce



DO RANDOM STUFF AT RANDOM TIMES.


Carry On....
Old 09-17-2012, 12:40 PM
  #63  
jester_s1
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Default RE: landing bounce

Acdii- Admittedly off topic, but your experience underscores the value of a proper flying location. A club field would be smooth and flat, which means easier takeoffs and landings, and no trees or fences to hit. Maybe the nearest club is too far from you to be practical, but if not it's a good investment. It may not actually save you money, but it will save you aggravation and repairing time.
Old 09-17-2012, 03:16 PM
  #64  
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Default RE: landing bounce

I've been trying to contact the guy for the club 20 minutes from me, with no luck. The other one is 40 minutes away and in another county so a park district pass is costly. The one close to me is unmarked and I have no idea where it actually is.  Where I normally fly is not a bad place to fly, and I usually dont have mishaps unless I misjudge the plane from me. What happened yesterday was a fluke, and with a plane I have not a lot of time on, which coupled with the cross winds, led to me treeing it.

Besides, repairs are half the fun, otherwise I wouldnt have much to do when I dont fly!
Old 09-20-2012, 01:28 PM
  #65  
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Default RE: landing bounce

Well, the guy did not bring the 4* to the field. However, he had a Hangar 9 Ultra Stick he wanted me to test fly. I flew it, trimmed it out and landed it with zero issues. Then he flies it and I noticed he was landing long just like the 4* did. I walked out to the flying station to and started to question his landing technique with him. The plane was sitting still on the runway but the motor was running. I asked why and he flipped a switch on his Tx and the motor stopped.

Problem identified. He has his planes set up so that the motor will run when the throttle is at full down. This is done by a sort of throttle hold feature on the radio. He is so worried about stalling the plane in the landing approach, he flips the switch and the motor runs at partial power while he attempts to land. Then he switches it off while taxing back to his station. He has it set low enough so that it doesn't pull the plane on the ground but provides a slight amount of thrust during his landings. It is just enough thrust to cause the airplane to "float" for an excessive amount time. I'm sure the thrust also contributes to the bouncing issue. He has got to learn to trust his planes won't fall out of the sky when bringing the throttle to idle.

Anyway, the issue is landing technique in this case.

Mike
Old 09-20-2012, 03:55 PM
  #66  
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Default RE: landing bounce

It pays to ask questions and watch closely with newbies. They have fears and, as often as not, misunderstandings, or just lack of understanding certain aspects of flight. Toss in the added idiosyncrasies of models in flight, and they're in even deeper.

Learning to tune a motor so that it doesn't stall is critical. Learning to land properly is crucial. It wasn't clear whether he was running an electric or a glow, but if it's a glow, he probably hasn't learned how to tune a motor so it will idle dependably.

All pretty standard stuff that newbies face. The guys in his club should take the time to help him sort it out. Sounds like you're already starting on that.

~ Jim ~
Old 09-20-2012, 05:09 PM
  #67  
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Default RE: landing bounce

Jim

It is electric.

Mike
Old 09-20-2012, 05:13 PM
  #68  
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Default RE: landing bounce

Wow.

He needs to learn the joys of dead-stick landings. I'm not a fan of electrics, but that's one feature that shines about electrics; being able to chop that throttle and glide in for a nice landing. And still power up for a go-round if you're not lined up right.

He'll get there.

~ Jim ~
Old 09-21-2012, 05:39 AM
  #69  
jester_s1
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Default RE: landing bounce

Show him how to float the plane around in a flared attitude. With those stall resistant wings, trainers are great for that (as are sticks) as they can almost be in a harrier attitude and not drop. If he can learn to hold the nose up and control his altitude with the throttle, he'll learn to land very precisely. Obviously this won't work with a warbird or many aerobatic models, but it's a step in learning to do a proper flare and to land using throttle management.
Old 09-21-2012, 10:59 AM
  #70  
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Default RE: landing bounce

Guys, this is about run its course. And truly it has wandered away from any link to aerodynamics or design dynamics.

We'll give it the rest of the day in case anyone has any last moment thoughts and then it'll be locked to fade away.
Old 09-21-2012, 04:26 PM
  #71  
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Default RE: landing bounce

the way to avoid a bounce is to touch on the tail wheel first...
Old 09-21-2012, 05:17 PM
  #72  
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Default RE: landing bounce

There is a good article in the latest Model Aviation magazine. Good reading.
Old 09-24-2012, 11:52 AM
  #73  
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Default RE: landing bounce

Thread closed....

If there is still any questions about how best to fly a model to avoid a bounce on landing then the discussion should be put into the Questions and Answers forum or Beginner forum or in a forum that deals with whatever style of model is at issue.
Old 06-10-2016, 07:09 PM
  #74  
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The best landing plane I have is my Sig Kobra and even after a few landing that should have resulting in a bounce it always sticks to the runway. Second best That I have owned is my Goldberg Tiger
Old 06-11-2016, 10:49 AM
  #75  
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Trike gear don't count because the main gear is in back of the CG.
Originally Posted by mustangherb View Post
The best landing plane I have is my Sig Kobra and even after a few landing that should have resulting in a bounce it always sticks to the runway. Second best That I have owned is my Goldberg Tiger

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