28 Aug 2025
MTD-01-2025 - 'Inspection of horizontal stabiliser (tailplane) attachment brackets and associated hardware for cracks, looseness and other forms of distress' for Zenair CH601, CH650, CH701, CH750 and variants of these four models has been upissued to Issue 2. This is in order to correct an error in the 'Effective Date' of this MTD. This MTD can be found HEREÂ and is also available below.
A number of cases have been found whereby the structural integrity of the horizontal stabiliser mountings on the Zenair types identified above have been compromised by one or more of the following:
cracking of the attachment brackets
oversize holes
loose rivets
distorted and chafed brackets.
These problems could occur due to a number of factors including poor build quality, a build-up of tolerances in the positioning or dimensions of the brackets, improper assembly, rough treatment or in-flight vibration. Failure of a tailplane attachment could result in degraded controllability in flight or loss of control.
Special inspections of this area have been recommended by Zenair since January 2017, in their document ‘Mandatory Action. Jan. 2017 – Inspection of Horizontal Stabilizer tail attachment brackets’. This Mandatory Technical Directive mandates this safety action for aircraft operating on LAA Permits to Fly.