Shock struts XL

[grdev]

Is the "V" strut setup really necessary if you just use low pressure tires for shock loads? Why couldn't you just insert a tube from where the V would normally attach and that would hold the gear from moving in or out. It would be less parts, so less weight, but I don't know if the change in geometry would adversely affect the fuselage.

[Sam Buchanan]

Is the "V" strut setup really necessary if you just use low pressure tires for shock loads? Why couldn't you just insert a tube from where the V would normally attach and that would hold the gear from moving in or out. It would be less parts, so less weight, but I don't know if the change in geometry would adversely affect the fuselage.

Here is what is probably the simplest, lightest version of the XL gear you can build:



I flew this gear for a season and it worked great.


Not sure what you are asking in your question--is this it?



If you eliminated the vee and went with single long tubes I would be concerned about them buckling under compression loads.

[grdev]

I was thinking about installing cables just as you have them. On station #2 on the gear bracket you use the outer 1/4" hole for the gear leg, with the inter 1/4" hole, same bracket you install the V bracket on. I want to know if you don't install the V bracket, rather you run a tube down to each axle on each side to keep the wheels from shifting inward just like your straight tube between the wheels do. The cable would take the load normally seen by the V strut.

[grdev]

Well it is on it's gear, well almost  ;D

[grdev]

is there any reason why this strut, along with cross cables will not work?

[rockiedog2]

I believe the engineers will tell you that is a very weak gear for inboard side loads and will likely fail under minimal compression loads. also the close proximity of the brace strut to the main gear leg is high drag. the plans gear has been proven to be the most efficient for planes of our type and is difficult to improve. I installed a well thought out and executed carbon fiber low drag leaf gear on mine and the gain was near nil but the difficulty was way more than the plans gear.

[Sam Buchanan]

is there any reason why this strut, along with cross cables will not work?

Yes, I think there are very sound engineering reasons why that design will fail when subjected to side loads.

Modify the gear only with valid engineering analysis. A gear failure is a big deal, most likely will result in engine, prop, and airframe damage......in other words, you will wreck your plane.......

The gear built to plans works really nicely.

[grdev]

I believe the engineers will tell you that is a very weak gear for inboard side loads and will likely fail under minimal compression loads. also the close proximity of the brace strut to the main gear leg is high drag. the plans gear has been proven to be the most efficient for planes of our type and is difficult to improve. I installed a well thought out and executed carbon fiber low drag leaf gear on mine and the gain was near nil but the difficulty was way more than the plans gear.
I will just follow the plans:)  But it is fun to consider alternatives if she comes in heavy. 

[grdev]

It is 50 pounds the way she sits. Have to watch every ounce. I can't tell for sure, but the gear may not have any toe in. I'll pull the wheels off  tomorrow and check. It sure rools well on pavement, so I can't be very far off

[Sam Buchanan]

I like that gear, Gil. 

[grdev]

Thanks Sam.;D

[Poorman2]

Gil, It looks like you left out a diaginal from station one to station two above the foot well.

[grdev]

Not on purpose, just ran out of 5/8" tubing.