I'm currently doing the annual inspection on my 10 year old 320hrs TT RV12 and discovered wear on the LP4-3 rivets that connect the inboard rear rib to the left main spar.
See photos:
Angle: https://photos.app.goo.gl/zU1QMEnBDZEkScWN7
Topmost rivet: https://photos.app.goo.gl/eqRnvbvNeLd6fpb89
Second topmost: https://photos.app.goo.gl/zhgvyAcDqmM2hYTV6
Third rivet: https://photos.app.goo.gl/MQmaZEx9aqUADZzVA
Bottom rivet: https://photos.app.goo.gl/BmNR6KJTFoGbwY8f9
End of Left main spar: https://photos.app.goo.gl/wTmkS1xo119vBtUy7
I'm guessing this wear is due to play in the wings. I've performed the MM Rear Spar Doubler check and measure 0.038" movement in the Left wing and 0.026" in the Right wing. I did the check by myself so I'm unsure how accurate that is, but would seem to indicate some movement. The maintenance manual says 0.050" is acceptable with the new ES-00076 & ES00077 Electrical Connectors but 0.010" with the old UHMW ones.
Last year I installed landing and position lights, but removed the UHMW connector and just wired in a molex connector for the lights. Does anyone know why the new electrical connectors increase the play tolerance? Did I introduce this play by removing the UHMW blocks?
See photos:
Angle: https://photos.app.goo.gl/zU1QMEnBDZEkScWN7
Topmost rivet: https://photos.app.goo.gl/eqRnvbvNeLd6fpb89
Second topmost: https://photos.app.goo.gl/zhgvyAcDqmM2hYTV6
Third rivet: https://photos.app.goo.gl/MQmaZEx9aqUADZzVA
Bottom rivet: https://photos.app.goo.gl/BmNR6KJTFoGbwY8f9
End of Left main spar: https://photos.app.goo.gl/wTmkS1xo119vBtUy7
I'm guessing this wear is due to play in the wings. I've performed the MM Rear Spar Doubler check and measure 0.038" movement in the Left wing and 0.026" in the Right wing. I did the check by myself so I'm unsure how accurate that is, but would seem to indicate some movement. The maintenance manual says 0.050" is acceptable with the new ES-00076 & ES00077 Electrical Connectors but 0.010" with the old UHMW ones.
Last year I installed landing and position lights, but removed the UHMW connector and just wired in a molex connector for the lights. Does anyone know why the new electrical connectors increase the play tolerance? Did I introduce this play by removing the UHMW blocks?