Gluing fabric into windshield channel - best practice

[Mark Goldberg]

After reading about Tim's problem - it seems appropriate to provide Bob's guidance on how best to do this.

Bob leaves about 1" of extra fabric to glue into the channel. He glues it in there and then also places a 2" finishing tape across on top with also 1" also to be glued into the channel. The other half of the width of the finishing tape is just used normally on top of the ceiling fabric.

The above is pretty much what I did on my four place 1900 hours and 18 years ago.

Bob waits until the last to install his windshield. Then he uses black RTV to fill in any open space in the channel. This serves two purposes. It helps keep rain out and also helps that fabric stay in place.

And the last thing you need to do is to rib stitch the ceiling fabric back to the rear spar. Low pressure is created up there and the fabric will, on some planes, billow out/upward in the ceiling area. The rib stitching keeps it from doing this and also is a good precaution if the fabric ever comes out of the channel for any reason.

In the 1950's & 1960's - there were a few accidents with Pipers where just this happened. If enough fabric comes loose and drapes over the tail surfaces - it can be very bad.

Hope this helps. Mark

[rodsmith]

Steve Wittman had this happen on his last flight with fatal results. I think it was a Wittman Tailwind. Enough fabric peeled back to interfere with the tail surfaces.

[Mark Goldberg]

Rod, my recollection is that the fabric failure that killed Steve Wittman had to do with fabric glued to the plywood covering of a wing. It came loose and wrapped around an aileron. Maybe the tail surfaces but that is not what I remember. Mark

[coosbo]

I think this is the NTSB report. Says he was 91 with a current medical and almost 17,000 hour! https://app.ntsb.gov/pdfgenerator/Re...Final&IType=FA

[rv8bldr]

I think he and his wife were on their way back to Osh from Ocala, FL. He called the airplane the O&O Special (Osh and Ocala).