While we were in Daytona Beach, Van’s Aircraft released two Service Bulletins to address cracks in RV elevators and horizontal stabilizers. Van’s recommended that all affected aircraft be inspected before the next flight.
SB 14–01–31, “Hoizontal Stabilizer Cracks”, applicable to RV–6, –7 and –8 (and the tricycle gear variants) calls for an inspection of the horizontal stabilizer front spar for cracks, and provides details on a repair if cracks are found. The first cracks were found by Van’s Aircraft during an annual inspection of one of their high time demo aircraft. They checked other local aircraft, and found quite a few with similar cracks. They then developed a horizontal stabilizer front spar reinforcement and instructions to make this modification on already completed aircraft. The modification can optionally be made even if cracks are not found, in the hope of avoiding cracks to develop in the future.
Since this SB has been released, informal info gleaned from the Vans Airforce (VAF) web forums suggest roughly 10% of the aircraft that are inspected have these cracks. The large number of in-service aircraft with the cracks, with no known failures, strongly suggest that aircraft can fly safely for years in this condition.
SB 14–02–05,“Cracks in Elevator Spar”, applicable to RV–3, –4, –6, –7 and –8 calls for an inspection of the elevator spars for cracks. This has its roots in cracks that were found by an RV owner during an inspection. He reported his cracks to Vans, and on the VAF forums. I am aware of two other RVs that were found to have similar cracks. I inspected my elevators after reading the reports on VAF many months ago, and found
SB 14–02–05 provides inspection procedures and instructions for a repair if cracks are found.
Today I did the inspections for both SBs, and was happy to find no cracks. Given the significant percentage of aircraft that eventually develop the horizontal stab spar cracks, I may remove the tail and do the mod next winter. This thread on VAF gives a good perspective on the details of the mod.
