Overview of Chapter 18 - the canopy

The Long-EZ canopy is purchased from a 3rd party source, but the builder is still responsible for making the composite frame all around it.

While I was learning about Long-EZ's before I started building mine, I noticed at airshows how many Long-EZ's had a "kink" between the canopy and their cowl. I remember thinking, "What is going on here?!" Also, a lot of them don't seem to carry a smooth spline from the nose, to the canopy, to the firewall and aft engine cowl. I think the reason this happens is because the plans has us build all these chapters independently of each other. Because of this, I decided to build mine all in one shot.

The plans has us make 4 blocks that suspend the canopy in the location we want...

We then bond a bunch of foam blocks around it, shape it, and glass it.

After the outside is glassed, the canopy and frame is removed from the fuselage, turned upside-down on the bench, where the interior layups can be completed. Hinge and latch hardware is then installed.


Canopy flange: CP #26 under builder hints tells us it's ok to remove the flange around the canopy (the drawing below shows the original flange per plans). Removing this flange prevents stress risers and reduces the chances of developing cracks in the canopy in the future. Since the flange is removed, this requires changing the blocks that hold the canopy in place while we bond foam blocks to it and glass the outside.

Drip trays: CP #35 under builder hints also tries to warn us about potential seal problems later on. The original plans canopy doesn't have much of a seal between the canopy frame and fuselage. Builders have gotten clever about this and have made drip trays for a better rain seal; however, instructions on this isn't very clear. I'll have to come up with a clear plan on how to tackle this as I go.

Canopy frame warping: CPs don't mention anything about this, but previous builders have warned me about their canopy warping in flight and causing air leaks - typically in the front corners. I will consider adding a ply of carbon fiber to try and stiffen the canopy frame.

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