Hi,
Has anyone figured out how to get the nose gear door on Kerry's Vampire to work?
Seems to me I've spent as much time trying to figure it out as it did to build the plane (not really, but it's brought construction to halt).
Any ideas or pics would be greatly appreciated.
Jon

There was a thread on this very topic last April (or thereabouts)...some good pictures were posted....


What I'm curious about is that triangle shaped notch on the sideways closing door. The two place Vamps have a similar shaped plate attached to the struct which covers this when the gear is retracted, but I can't find anything of how the single placers covered this "hole" when the gear is retracted...or for that matter why it is even there..?????

Nony,
I started this thread because the other thread is so long.
The problem with that thread is, it shows how the real door works. Because the geometry of the retracts is different than the real thing, pivot point/location, you can't do it the way DH did it. All I know is I must be missing something because no matter what I try, I can't get it to work. On the other thread I figured out the pivot point for the NG door to work properly, but you can't get it to fit inside the model; it's forward of the #1 former, almost touching the f/g nose cap, there's just not enough room. Tried Robart offset hinges, that didn't work, in fact, everything I tried hasn't worked!. It's pretty frustrating, I finally can get back to finish the construction, only to be held up by a stupid door!
I'm not sure I understand your question, but the door fits in the fuse as the fuse opening is a mirror of the door, 45 degree notch and all.
Have no idea why they would've made the door that way.
BRG,
Jon

I know 3 people with Vamps, one took a Vamp to the World Scale Champs so I'm sure he has it figured. I'll probably see him at a jet fly in about 3 weeks, I'll quiz him.

I'll email the othe 2 guys. They all fly 2 seaters, is that of use? Ahh, poor Jon, have you never had the 'pleasure' of owning a British car? - John.

The top/forward hinge is more like an "H" acting as a standoff and with the legs just long enough to enable the door to close flush.
The bottom/aft of the door is hinged to the gear leg.
Even with a different geometry of the retract, this should be possible to copy with the necessary adjustment of the length of the "H".

Boomerang,
The two seater's nose gear door is different than the single seater.
Anyways,thanks for the help.
BRG,
Jon

See what I mean about that 45 degree notch? There is no correcsponding plate in the nosewheel bay to cover it when retracted. (I know Kerry has one in his plans...).
Just one of those why? and how? mysteries.

That geometry of the front nose gear door is pretty complex with offset hinges and angles. Would it work if you used offset door hinges at the front so that it looks scale when the gear is down, and used spring pressure to close it - ie no struts at the rear of the door- the nose gear would push it open, and allow it ot close when retracted, Kingcat style....just a thought.

Nony,
I finally figured out the geometry. I'm going to make a couple of "L" brackets that will be mounted by the forward retract mount holes and another bracket on the inside of the door. I'll use 2-56 rods with a nylon mini clevis on one end and solder a piece of brass for the rear pivot. I'm going to operate it with a small air cylinder that I hope I can time with the retract so the door and the N/G operate together. The only thing I'm concerned about is, because of the air loads, the top of the door might dig into the top opening in the nose cap when the door opens, jamming the door and breaking it. I think if I put in a bevel on the nose and the top of the door it should be OK.
I'm going to try to set it up tomorrow, if it works I'll take a couple of pictures.
BRG,
Jon

Do you have any pics of your model and the progress you have made?

Not recent ones.
I had some personal problems this summer and didn't get a chance to work on it.
Everything is done, the only unresolved issues are the door, the main L/G doesn't retract completely in the well, I'm going to call Daryl at Sierra Precision tomorrow and see if there's a fix and setting up the sliding canopy.
Right now I'm installing all the servo's, all 14 of them, the airlines and valves, then the fuel system.
It'll be ready for f/g in Jan. I decided on a color scheme and my buddy is going to paint it for me.
If I get a chance this week, I'll set it up and take a couple of pics.
Jon

Hope somebody can answer Nony on the notch. Seems like they flew with the triangle open. Maybe it was needed to make the door clear the leg during retraction/extension. The door is pushed open and closed by the leg and held in position by an over-center spring mechanism. Could be an air intake, but the cabin ram air intake is the little hole in the center of the nose.

Per

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Thanks for the pics Per....

The 2 place versions have a triangle shaped piece at the end of a stand-off attached to the nosegear strut...this would cover the notch when the gear is retracted....

Hi Jon:

The nose gear - forward door works with 2 mechanisms. The first is a trapeze attached at the TOP of the door and just inside the nose gear opening in the fuse. This allows for the door to swing OUT away from the fuselage and UP when it opens.

The 2nd attach point is from the door to the lower strut directly. You will not be able to connect at this specific location on your gear but just above it.

Please see photo and I have attached the DeHavilland VAMPIRE manual drawing to illustrate.

If you still have questions please give me a call.