7.2 Nose Gear Installation (Door mechanism)

This entry is part 1 of 39 in the series 07 - Landing Gear

This is an area that’s been bugging me since day 1. The main gear doors a attached to the gear legs. But the nose doors are hinged. They are brought up by means of a rather complicated hydraulic system. Here’s a picture of a completed plane.

This picture is looking aft at the canard bulkhead. The greenish looking pipe going down is the nose gear leg. The opening at the bottom is the space that the nose gear comes through when it retracts. You can see the rear hinge arms of the nose gear doors (they’re white). Those doors are closed by a hydraulic cylinder (gold at the top center partially behind the large red flexible duct) which pulls up on a pair of arms that extend down to the door hinges. The hydraulic cylinder is activated by a switch (off to the right near the bottom of the cylinder) that gets triggered when the nose gear is up.

I’ve seen a couple other builders that used this method. After some investigation, I found the guy who builds these.

I asked the builder who came up with this if he could build one for me. But his fabrication guy was unavailable. So Malcolm told me he had built one that it’s in a plane nearby. A call to Terry Miles had me stopping by to take some pictures and measurements.

Same view as the previous picture but with the Hangar 18 mechanism.

The spring is so that when the gear bounces a little while in the up position, the doors will stay closed.

Some fabrication I can do. But I’m not a welder and I don’t have a milling machine. So Lynn, my current A&P put me touch with a guy who put me in touch with a guy who does metal work. I sent him my drawings and measurements. In return, he sent me:

Here are those parts installed.

Now I have to get the linkage and spring so I can drill for the pins to fix the arms in place.

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