Ed

My Chipmunk is bouncing badly at touchdown. It has very stiff struts. Would reducing my elevator to Low rates just for landing, or adding some Expo help ? ? ? []

Thanks for your help .

abufletcher

I've got one of the Black Horse ARF Chipmunks and I haven't had problems with landings (despite the fixed music wire struts). Can you slow the model down on final? And also forget about 3-point landings. That is to say, forget about doing a last minute flair just above the ground (which is what I assume you're doing from your comment about the elevator). Frankly, I use little to no elevator on landing. It's much better just to bring the model in on a very shallow approach and fly it right onto the main gear. After the main gear is down then just let the tail settle on its own.

Does your model have flaps? I did have a few bumpy landing when I tried to land with full flaps. Basically, I let it get too slow and it was just dropping out of "the sky" just before touching down and on a few occasions I bent the struts. The key there is to keep the power on until the gear actually touches the ground. Also I now only use "half flaps" on landing.

beepee

Some of my birds have a problem bouncing. When I have a consistent problem with it, I will add just a touch of throttle as I flair. That helps reduce the decent to a nice soft kiss of the ground. ... that is if I do it all right. Sometimes when we come in too slow, we get on the backside of the power curve. That is where things start working backwards. Pull on the elevator to arrest the decent and she comes down faster. Bounce time!

Keep working it. Developing a good technique is part of the fun.

Good luck,

Bedford

MajorTomski

I had problems with the GP Ryan STA until I remembered a trick a 1:1 Cessna 170 pilot showed me. Plan on a slightly nose high wheel landing, not a three point, then just as the wheels kiss the grass or the pavement RELEASE the up elevator or even add just a HINT of down elevator. It fixes the reson for the bounce in the first place; high angle of attack.


If you think about it at the point of the bounce, you're going from a low angle of attack to a high angle of attack, thus for a moment the wing is generating enough lift to keep the nose up. You holding in up elevator contributes to the problem. Sticking the plane to the ground with no or down elevator reduces the AOA and reduces the major lift force that helps with the bounce.

It works for me on all my taildraggers

MTC YMMV

Tom

David Bathe

And check the CG isn't to far forward.

Dr1Driver

Ideally, the plane should stall just as the wheels touch. It sounds like you're coming in too steep and flaring too high and it's dropping in. Come in at a more level attitude but with the nose slightly down and allow the speed to bleed off. Release all elevator as soon as the wheels touch.

Chip_Mull

My Feedback: (1)

I agree with MajorTomski. I was watching one of the Madera racers once and he never bounced the T-6 on landing, NEVER. I asked him what his secret to perfect landing was and he said "You justa leta go when she touches down, justa leta go. Just watch the wheels, nothing else.". You normally have either a little backpressure on the elevator or trimmed for a nose up landing so releasing the backpressure plants the gear. Landing a seaplane is exactly the same.

Ed

" then just as the wheels kiss the grass or the pavement RELEASE the up elevator " All good advice here, and I'm gonna try the release holding up elevator as the wheels touch down idea by Tom. I think that my problem has been trying to flair it into 3 pointing. I think that holding the stick back at touchdown has been getting me sideways, and breaking out my landing gear. I loose directional control, scrape wing tips, and break out my landing gear. I think that i need to concentrate on doing a wheels landing and keeping it moving straight. I fly off of pavement, the wheels stick, and it gets sideways. [] Should i worry about reducing my landings to using Low rates, or Expo ?

JL1

My Feedback: (93)

Flair the plane and hold it a few inches above ground with elevator. Hold that height while slowlyincreasing elevetor (raising the nose slowly without gaining altitude) until the wing quits flying and the plane drops to the gound.

gene6029

I reduce my elevator throw to <1/4" throw on my Chipmunk when landing. I use the throttle to control my decent/accent until im over the threshold. Then i cut it and flair til the wheels touch.( There isnt enough elevator throw to balloon the model back into the air).I also imploy the use of flaps, & they greatly reduce the airspeed. Here are a few pics of my Dynaflite Chipmunk w flaps.....Gene

gene6029

One more.....Gene

Chip_Mull

My Feedback: (1)

Left thumb, left thumb, left thumb. Concentrate on using that left stick. So many people fly around using the ailerons and when it comes time to land, they forget how important directional control with the rudder becomes. Check the alignment of the gear and be sure you haven't tweaked one of the gear to exacerbate the problme.