Viper Tail Modification

by Paul Herman

Here is my solution for the weakness in the Viper and Predator at the V-Tail leading edge. The design of both aircraft cause a weak spot right at the front of the V-Tail. An additional problem is the rigid rear tail skid which creates a long lever. This give leverage which will crack the fuselage sides during launch or tail 'smack-down' landing. 

Since my first Predator broke it's tail off after a few heats in a race, I have been doing this on all Predators and they have taken abuse well. 

This modification is especially important if Bill Vargas is going to launch your plane. They don't call him 'Rocket Launch Man' for nothing.

Step one - Remove the bottom sheet covering. I widened the antenna tube notch to move the tube to one side. Note that I do NOT have my antenna trailing out the rear. I have seen at least 3 antennas stepped on during launch, pulling them out. I saw one pulled out just picking the plane up to ID it. 

Step two - Cut out carbon fiber or thin plywood doublers and saw alongside the fuselage sides with a Zona saw into the V-Tail mounting block at a 45 degree angle. 

Step three - Epoxy the doublers in and mount a music sire skid. 

Step four - re-sheet the bottom.

News  Officers  Forums  Member List  Join

Send mail to DonStegall@carolina.rr.com with questions or comments about this web site.
Copyright © 2003-2005 RCPRO.org
Last modified: August 01, 2008