FAA Issues Rudder Stop ĎADí on Swept-Tail Cessna 150/152
May 14, 2009 — Despite comments from the Cessna Pilots Association and other interested parties, the FAA has issued AD 2009-10-09, effective June 17, 2009, requiring the installation of a new rudder stop modification kit on all models of the slant-tail versions of the Cessna 150 and 152, or, in lieu of the kit’s installation, the aircraft must be placarded against intentional spins and other acrobatic maneuvers. The AD must be complied with within 100 hours Time In Service (TIS) after June 17, 2009, or within the first 12 months, whichever occurs first.
Tom Carr of CPA, an experienced A&P mechanic with decades of experience concerning Cessna aircraft maintenance, commented that since the two aircraft involved in fatal spin-related accidents cited in the proposed AD issued in 2007 were not in compliance with the aircraft’s type design the issues surrounding the proposed AD were better served by the issuance of a Special Airworthiness Inspection Bulletin, rather than an AD. (One aircraft, which crashed in 2005, had the rudder stop installed upside down, compromising the control system’s functionality; on the other accident aircraft, which crashed in Canada in 1998, the rudder most likely was pushed over by outside forces acting during the accident sequence. On that aircraft the rudder control system had known maintenance-related issues, which rendered the aircraft unairworthy, yet the aircraft was still flown.)
While Cessna created a modification kit in 2001 to enhance the design of the rudder stop (a kit that has subsequently been redesigned and given a new part number), there have been no failures of the aircraft’s rudder control system which would lead one to belive the aircraft’s type design was at fault. On the contrary, as is true with many other systems on an aircraft, if the aircraft is maintained in compliance with the type design standards, the aircraft will continue to operate as intended. But if maintenance fails to detect a failure or induces a failure of the system, then the aircraft is unairworthy. An SAIB, coupled with revised maintenance/inspection procedures, is a reasonable and prudent way to address a maintenance-related issue such as this.
For more information on the issuance of the AD, it can be viewed on the FAA’s website at www.faa.gov, click on the Regulations & Policies tab and then click on the link for Airworthiness Directives. Enter the AD number AD2009-10-09, or just click on the New ADs link on the right side of the page to review the list of recently issued ADs.