Tip: Making the Slider Canopy Fit

After building a 9A and helping several friends make their sliding canopy frames fit, I've done some investigations.

First of all, I've talked to Van's about the issue, and they know there is an issue, but the canopy frames are all jig-built and they can't determine why there is a problem with some aircraft.

With the help of a friend, I did a survey of some local RV's with sliders to determine if the fuselage was the big variable. In short, the answer is YES.

Here's some examples:
At roll bar At top aft skin/longeron intersection.
1. 42 3/4 " 40 11/16
2. 42 7/8 " 40 7/8"
3. 42 1/2 " 40 7/8 "
4. 43" 40 3/4" (my RV-9A, QB fuse)

So it appears that there is quite a bit of variation in width (up to 1/2") at the roll bar position. This makes sense, because this dimension is not controlled very well during construction.

I've seen some folks with narrow fuselages have to bend the roll bar (quite a task), but the canopy frame fits well. The opposite is also true-- those that don't have to bend the roll bar have to cut and weld the canopy frame (as I did). These 'wide' fuselages also have large fish-mouths in the aft part of the canopy tracks where they need to be trimmed flush with the fuse.

So, based on my experience, here is a method for making the canopy frame adjustable for a perfect fit.



Good luck!

Here's some pictures of how the shape of my fuselage is different than a friend's. The cardboard template was cut from his fuselage, and you can see that there is about a 1/8" gap at the seat back location.

My fuse is wide at the rollbar (43") compared to others (see previous post), and this forces my fuselage into a different shape.

The result is a big variation in the canopy frame fit, which was the root of all of my fit problems.




V

Thanks, Vernon. Very helpful information. I'll be starting my RV-7 canopy in May.