What is this Bump on tail of my RV-7?

[dilamipo]

hello forum,
I noticed this bump on the tail of my rv7.
What could be due?

[petersb]

Originally Posted by dilamipo

hello forum,
I noticed this bump on the tail of my rv7.
What could be due?

Looks like a hard landing to me. The crease goes through the inspection plate so it can't be a manufacturing error. It could possibly have changed the incidence of the stabilizer slightly to negative thus requiring a little foreward trim in level flight.

[High_Flyer]

Hi,

This is quite common on RV-tailwheel using bumpy grass runways...
The cure is to rivet an angle just below the inspection plate.

Here are 3 pictures I received from another builder in the U.K.
I've done it on my RV-7 (not flying yet), very easy to do. I used some surplus angle received with my kit.







Alain.

[Robert Anglin]

Originally Posted by petersb

Looks like a hard landing to me. The crease goes through the inspection plate so it can't be a manufacturing error. It could possibly have changed the incidence of the stabilizer slightly to negative thus requiring a little foreward trim in level flight.

The smoking rivets behind the rudder cable would seem to indicate something more than just the common hump at this site has happened here.
Most every thing has a fix, it just takes time and some sheet metal work.
Yours, R.E.A. III #80888

[brad walton]

Good eye Robert. Looks like there was some excessive tail wheel loads beyond the design capabilities

[Pat Hatch]

Dimitri,
I agree with the other posters that it looks like your tail area took some kind of a hit. I notice that the leading edge to the tailwheel fork at the bottom shows a lot a wear, possibly may even have taken a blow of some kind--like falling into a pothole or something.

If it were me, I would pull everything apart, remove your tailwheel spring, remove the horizontal stab/vertical stab and rudder because you are going to need access to assess the damage and do the repair.

One other recommendation: looks like you could really use one of the after-market tailwheel forks like those sold by JD Air or Vince Frazier. This might prevent the kind of damage that apparently happened here.

[Mel]

And while you're at it, change the rudder cable attach bolts to drilled bolts with castilated nuts and cotter pins.

[Ironflight]

To me it looks like a classic case of side-loading the tailwheel - it falls off the pavement and gets caught on an edge, or the two bolts that hold the socket to teh spring shear as the tail is being swung around and it falls off an edge. Either way, the tailwheel itself comes to a sudden stop while the fuselage is still trying to swing, and you put a slight kink in the fuselage structure. I've seen it on a couple airplane's, and both have had a sudden tailwheel stop event.

Just one possibility.

Paul

[BillL]

I have been monitoring (then posting) VAF for a decade. I tend to remember all the issues that affect my model (-7), but again, VAF has surprised me with new, valuable, and relevant information.

Thanks DR, and apologies to the OP for the off topic comment.

[Mel]

Originally Posted by High_Flyer

This is quite common on RV-tailwheel using bumpy grass runways...
The cure is to rivet an angle just below the inspection plate.

I disagree that this is common. I've inspected a lot of RVs over the last 35 or so years and I find this rare. Yes, I've seen it, but not often.