Series 5 Vixen elevator

[FoxBob]

I screwed up fitting the ribs into the tubing frame of my elevator; sort of jammed them in rather than relieving enough wood to make a light touch-fit. Many of them warped after some months and I am about to replace them, using the old ones as templates to cut new plywood, and adding stiffeners. For some reason, all the longer HS ribs that are not against metal have stiffeners, but not the elevator ribs, per the plans. I notice that the Series 7 SS elevator is larger and wonder whether there would be any advantage to fitting it to an otherwise stock Series 5 Vixen, as I am remanufacturing my elevator anyway. I might fit an Airmaster CS prop, which would add a bit of front end weight, and the extra elevator authority (and weight) might help balance this. I will likely be fitting a Rotax 914 engine. I would like to hear opinions from other builders, especially those who have fitted Series 7 elevators to Series 5 aircraft with the Rotax 900 series engines.

Bob Miller
rmiller88@msn.com

[Esser]

I think the bigger elevator is a mod worth doing as a lot of model 5 guys end up doing it.

I also added stiffeners to my elevator ribs. I lived in a very humid climate when I first started building and the ribs were prone to warping without the stiffeners.

[jiott]

Definitely add the stiffeners to the elevator ribs. If you don't, when you shrink the fabric the tubing will pull in slightly and the ribs will assume an "S" shape.