12 Oct 2026
Mandatory Technical Directive MTD-07-2026 Issue 4 and Van’s Aircraft Service Bulletin SB 00134 Revision 2.2
MTD-07-2026 Issue 4 provides additional guidance on assessing deviations from the designed shape and position of the notches in the HS-714 flange, including clarification of when the position of a bolt hole relative to a notch requires additional repetitive inspections. It also corrects the socket size specified for identifying AN3 bolts from 7/16-inch to 3/8-inch AF.
What action is required?
Aircraft previously inspected under Issue 1 or 2: Check the bolt sizes and HS-714 notches in accordance with Issue 4 and complete the relevant entries in Appendix A.
Aircraft already inspected and found satisfactory under Issue 3: No further action is required.
All other applicable aircraft: Carry out the full inspection and measurements specified in SB 00134 Revision 2.2 and complete Appendix A.
Please refer to the documents below for full details of the inspection requirements and compliance timescales.