New nose gear MKll

[aircrafter]

Right where you see that rotation is very soft sand and I suspect it is sinking slightly into the softer stuff. I have been stuck in those spots with the original Vans nose wheel. We have been in drought conditions for sometime and as you can see, no ground cover on most of the strip.
I have no external shimmy dampener but using the internal friction of the oleo. Part of the testing is weather a shimmy dampener will be required, but at this point it seems fine.
Mick

[Canadian_JOY]

Mick - that looks like a pretty darned nice nose gear you've got there! You're absolutely right - to a casual observer the castor angle isn't readily visible, but from the video it's clear the castoring is working quite well.

My "flying" aircraft, a Davis DA2A, uses a similar style of steel "arch" to extend the nose gear outward and downward to the point of axel attachment. We've found there can be considerable lateral flexing with this style of gear, enough that some users (myself included) have had the fattest part of the tire rub against the inside surface of the "arch".

I'm not sure if I was seeing that sort of flexing happening in your gear when I watched your video (youtube quality limits our ability to see that level of detail). If you view the full HD video and see this type of flexing happening, it's fairly easy to add extra beef by welding a piece or two of steel tubing from the point where the oleo attaches then downward toward the axel. A good fillet of weld on the tube seems to produce the desired stiffening without adding too much weight.

Keep up the good work. This is a design I'd love to see "A" model builders have access to as an option to the stock Vans gear leg.

[aircrafter]

I did find the first couple of nose wheel forks flexing exactly as you describe. This one using a curve has lessened the side ways flex but there is some. No signs of rubbing but I would like it a bit stronger in side loading. Any chance you have a picture of your nose wheel fork?
Now that I'm happy with the basic design of the actual mounting and oleo, I will have a new one manufactured with a couple of weight saving changes. In a couple of weeks I should now the exact weight of the finished nose gear.
Mick

[Bill Boyd]

I really like this idea. The vid shows no detectable shimmy and the gear seems to track that torture-test runway surface very well indeed. Maybe you can post some video of the strut in action on a landing, especially one where the nose wheel is plopped on, or not enough flare and allowed to touch too soon. That would be the acid test.

Any tendency to shimmy on a hard-surface runway at high taxi or roll-out speeds?

Do you have a newsletter I can subscribe to?

Will you shut up and take my money?

-Stormy / RV-6A

[aircrafter]

Originally Posted by Bill Boyd

I really like this idea. The vid shows no detectable shimmy and the gear seems to track that torture-test runway surface very well indeed. Maybe you can post some video of the strut in action on a landing, especially one where the nose wheel is plopped on, or not enough flare and allowed to touch too soon. That would be the acid test.

Any tendency to shimmy on a hard-surface runway at high taxi or roll-out speeds?

Do you have a newsletter I can subscribe to?

Will you shut up and take my money?

-Stormy / RV-6A

Bill I'll take your money

Unfortunately my RV has yet to get its CofA. I'm having trouble with the fuel servo and in the video you can hear she's not running right, stumbles and missing at idle. Just another job on the list.
If anyone wants to help with testing I would be happy to discuss. Obviously someone in Aus would make it easier for logistics.
Mick

[Bayou Bert]

Hi Mick, great looking design.
What is the difference in the wheel base dimension from center line
of front wheel to center line of the mains, old vs new?

[Av8torTom]

I'm just curious. While shimmy is a common problem with free castering nose wheels, most RV-A users are more concerned with flip-overs. Do you have any reason to believe that this design will decrease this tendency?

[Richard@Langair]

Have you done anything different with how the new style gear leg is fastened into the plane?

There have been a couple instances where the bolt that holds the gear leg in the engine mount has sheared from excessive side loading/rotational forces likely due to having the swivel stop installed backward. Is your new leg design going to be applying similar sideways/rotational forces on that bolt?

Not trying to be a debbi downer at all, just wondering if some of the failures that have been seen on stock nose gear installations may find their way into this design.

[aircrafter]

I will try and answer the last couple of posts.

The wheel base has been kept as per original, I wanted to be able to use Vans weight and balance formula.

The design of the Vans nose gear has been discussed in detail here on the forum so I won't go into it. My gear uses an Oleo for suspension as opossed to bending so unless the gear shears or losses a nose wheel the chances of a roll over are slim.

One of the reasons for me starting on this design was the outcome from an engineer that done the loading testing for long range fuel tanks I designed. Although he had not been aware of the Vans nose gear design before seeing my aircraft, he was able to tell exactly where the failure would occur. One of his concerns was the single bolt attachment and the rotational forces applied to it.
My new gear also uses the single bolt at the top but also has a strengthening doubler mounted to the gussets of the engine mount nose gear socket. The nose gear uses a second bolt at this location to help with those rotational forces. At this point I have not seen any signs of movement at these locations.

Hope this answers your questions.

Cheers
Mick

[aircrafter]

Vans nose gear including nose wheel, minus fairings 21Lbs
New nose gear including larger nose wheel, minus fairings 24Lbs
I should be able to shave another pound from the next gear I'm having made.
Some of you may have noticed in the video that the engine was running a bit ruff at idle and throttle up, I initially thought it was the fuel servo needing attention but turned out to be the left mag. So no more testing until that is fixed.

Mick