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Extended gear?
http://t18.net/thorpforum/viewtopic.php?f=7&t=7200
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Author:  Hagle347 [ Wed Jan 16, 2013 9:17 pm ]
Post subject:  Extended gear?

Okay, does anybody have landing gear that looks like this? I can see the "why" it was done. I'm just not sure if its a one of a kind - and also question pushing the wheel axles forward. Anyone have suggestions on whether to keep it like this or change back to straight legs?

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Author:  leewwalton [ Wed Jan 16, 2013 9:29 pm ]
Post subject:  Re: Extended gear?

That's the opposite I what most extensions look like .. Most keep the line or move it slightly forward.

Author:  leewwalton [ Wed Jan 16, 2013 9:39 pm ]
Post subject:  Re: Extended gear?

Material looks way too thin as well .. Pull that off and live with a short gear or make some proper extensions. Just my opinion.

Author:  Hagle347 [ Wed Jan 16, 2013 11:23 pm ]
Post subject:  Re: Extended gear?

I don't have much information on the history of this airframe. I do know that it had flown for many years. I'm also making assumptions that it had an 0-320 with a constant speed prop. There is a good size piece of lead in the aft end of the airplane. I've yet to remove it so I don't know how much it weighs. My guess on the extended gear was to give some extra prop clearance. I have an 0-320 (160hp) to install on the airplane with an Aymar Dumuth wood prop. I think Lee's suggestion to remove the extensions and go back to stock will be a good move. I'm also looking forward to changing the tail spring to a tail rod.

Author:  Rich Brazell [ Thu Jan 17, 2013 12:06 am ]
Post subject:  Re: Extended gear?

CS to an AD prop is a BIG weight change ! I would have to look at my paper work , but I believe my AD prop tips the scales at 13 pounds ? I would prefer some sort of "cargo" in the baggage compartment to "lead" in the tail and have my AD prop ! ::)

RB O0

Author:  dickwolff [ Thu Jan 17, 2013 8:58 am ]
Post subject:  Re: Extended gear?

Are we looking at the left wheel or the right wheel? I'm assuming we are looking at the left and the intent was to move the axles forward.

Bill Cox, the original builder of my airplane, did something like this but as Lee pointed out... not as far. Mine are forward by roughly 1.5 inches (whatever the bolt spacing is on the axle.) I also agree with Rich.. those plates are way too thin. Mine are 5/8" thk, I think, and only about 5" or 6" long.

I believe the main reason this was done was to put the axle line back to approximately the same longitudinal position on the long gear as it would have been with the short gear. This was to make the airplane less vulnerable to nose-over on landing with forward CG, not having the stick firmly in your groin, and applying the brakes too hard and/or too early in the landing roll.

MLMP also had a CS prop on it at one point, apparently, so its empty CG would have been more forward.

If you have no history or documentation, I highly recommend you re-do your W&B and adjust the lead accordingly.


D

Author:  Scott Stine [ Thu Jan 17, 2013 9:38 am ]
Post subject:  Re: Extended gear?

The extension piece looks like it was made correctly, as per the newsletters.....however it appears as though it was not bolted on in the right orientation. I made the same gear leg extension as was recommeded in the NL but it is suposed to be bolted on vertically to extend the gear and keep it in line with the leg...moving it slightly forward. The material thickness of the extension looks similar to the material I made mine out of. Take it off, rotate it 90deg and send us another pic....

SS

Author:  Scott Stine [ Thu Jan 17, 2013 9:51 am ]
Post subject:  Re: Extended gear?

747

L gear leg extension

Author:  leewwalton [ Thu Jan 17, 2013 10:51 am ]
Post subject:  Re: Extended gear?

I disagree Scotter .. that extension is not per NL, it looks like the intention was to move the mains back more than increase length. Not sure why he would want to put more weight forward of the mains (especially with a CS prop) but regardless I'd say they are better used as artwork than on an airplane.

Here's the "keep the line" version.

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Author:  Scott Stine [ Thu Jan 17, 2013 12:00 pm ]
Post subject:  Re: Extended gear?

Assuming that is your R gear leg, isnt your extension moving the wheel down and back and mine is moving the wheel down and forward.....? With you constant speed guys dont you want the wheels moved forward?

Notice I didnt say back and to the left...especially for the Texas crowd.

Author:  leewwalton [ Thu Jan 17, 2013 1:45 pm ]
Post subject:  Re: Extended gear?

Well an extended gear is just that, simply extended, so the "keep the line" method duplicates that. There have been some extensions that move the wheels forward and a bit can't hurt, but the long gear airplanes (now much the norm) handle just fine.

Author:  mattst18 [ Thu Jan 17, 2013 2:13 pm ]
Post subject:  Re: Extended gear?

Just pointing out another obvious difference between Scott and Lee's leg extenders. Scott's are longer. (6 bolts on Lee's, 8 on Scott's)

I looks to me that if Hagle347 rotated his extentions down 90 degrees his would be similar to Scott's only maybe even longer... He may have to flip them over for clearance with the brakes. Plus it looks like maybe they are welded to the gear legs????

Author:  mattst18 [ Thu Jan 17, 2013 2:17 pm ]
Post subject:  Re: Extended gear?

Hagle347, the picture says "Left Main Gear", but this is the right main correct? My brakes are behind the axel, so I assume all are... :-\

Author:  leewwalton [ Thu Jan 17, 2013 2:21 pm ]
Post subject:  Re: Extended gear?

You're right Matt, Scott's extensions are per Newsletter 51 and are 2" extensions, mine raises 1".

Terry from the looks of things you're a ways off from needing to deal with this but when the time comes I recommend you make a set like Scott's, check out Newsletter 51.

Author:  Jim Mantyla [ Fri Jan 18, 2013 8:32 am ]
Post subject:  Re: Extended gear?

Guys,

I think the set up in the picture Lee posted was done so that the wheels could reach the ground.

Jim :-)

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