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Landing gear yay or ney on glider Thinking no but...

Old 01-16-2015, 04:41 AM
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gadgeter
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Default Landing gear yay or ney on glider Thinking no but...

I haven't flown this plane with the 2.6m wing yet and I wanted to try a controlled take off on wheels for maiden. I'm being told this is a bad idea. I was proud of my molded plastic retrofit .lol.
Any input appreciated
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Old 01-16-2015, 06:17 AM
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It can work... look at the Dynaflite Butterfly. Appx 99 inch span motor-glider with wheels.

The landing gear adds weight and drag, but when being used for test flights that's not a huge consideration as long as you ensure CG is a little forward inside the correct range. The wheels should be slightly forward of CG with the aircraft level and I recommend slight toe-in
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Old 01-16-2015, 07:57 AM
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Landing gear on a Glider is Just Fine , You have My Permission to use it LOL
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Old 01-16-2015, 08:44 AM
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Personally I look to REDUCE appendage / weight on a glider to increase it's flight envelope ...

On another thread - we have the discussion about folding prop and Brake ... To be honest if you are fitting wheels / legs - then the brake question is superfluous ... the wheels will make a huge difference to flight time and capability - far more than any prop folding.

Full size gliders usually only have a central wheel and small ones or skids on wing tips .. to keep weight to minimum.

My ASK 21 has a central nose wheel .. but does not allow use of prop on ground - not enough height.

My opinion anyway ...

Nigel
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Old 01-16-2015, 04:01 PM
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Prop windmilling creates a disc of drag almost as is you replaced it with a lexan disc the same diameter as the prop.

The landing gear produces far less drag.

But... He said he wants it on just for some test flights, to get the aircraft trimmed.
The landing gear lets you have both hands on the TX from the moment the aircraft starts to move. That can mean the difference between the aircraft surviving long enough to be trimmed and becoming a pile of scrap.

Using landing gear until its trimmed and has a few flights on it, then transitioning to the hand launches is fine.

For practice hand launching... buy a cheap foam 4.5 ft foam glider.... and add 3 oz on the CG. Cheaper to tear that up than the big RC sailplane.
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Old 01-16-2015, 05:35 PM
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I did see the mention of 'for maiden' ... and my bad for not qualifying my post better.

For maiden - yes why not but I posted based on human frailty and tendency to change mind !! It's wrong of me to have thought the wheels would become more of a maiden trial fixture and that was really my point.

As to the drag factor of folding prop vs wheels / U/C.

If we talk about a FIXED prop windmilling then I would totally agree with ffhuber. But this is a folder that as I observed on my ASK 21 and others ... if not braked - can windmill but they often do not completely unfold to a straight fixed mode ... more of a backward V ... meaning a substantially reduced disc area. So I suggest that drag from the prop vs wheels / U/C may not be such a cut and dried one greater than other. I agree that if prop does extend fully or nearly and windmill - then it would constitute greater drag.

Nigel
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Old 01-17-2015, 12:23 AM
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Thanks guys,
I do have some experience hand launching with smaller gliders however this 2.6m scares me a little. I will probably fit a single wheel after test flights as the fuselage does not have a very well built skid plate. (bout the only thing wrong with it)
Landu(volentex) Phoenix evolution convertable 1.6/2.6 span
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Old 01-17-2015, 01:53 AM
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at least I get to run/test motor on the deck
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Old 01-17-2015, 01:54 AM
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At least I get to test it on the deck
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Old 01-17-2015, 07:46 AM
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Originally Posted by gadgeter View Post
Thanks guys,
I do have some experience hand launching with smaller gliders however this 2.6m scares me a little. I will probably fit a single wheel after test flights as the fuselage does not have a very well built skid plate. (bout the only thing wrong with it)
Landu(volentex) Phoenix evolution convertable 1.6/2.6 span
Lanyu ? That's factory

VolantexRC is the 'trader' that took over from Lanyu Models some of the Lanyu line of models .. sadly inflating prices of them same day.

Just commenting ...

Nigel
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Old 01-18-2015, 02:07 AM
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Well the grass was too thick to take off from the deck. Had to hand launch but it did just fine. A little sluggish due to gear maybe but elev./spoil adj took care of that
I;ll send video
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Old 01-18-2015, 02:17 AM
  #12  
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Default Maiden Launch

Video Link Of Maiden launch
https://www.youtube.com/edit?o=U&video_id=ACQVspJs8l0
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