The FAA has issued an emergency airworthiness directive grounding all Raytheon Beech Model 45 aircraft, commonly known as T-34s. The action comes after the in-flight break-up of a Texas Air Aces-operated T-34 last week. The company uses the former military trainers to give customers a taste of mock aerial combat.
Although the T-34 bears some similarity to the Beech Bonanza, the wing spar issues are different, and this accident is not likely to directly affect Bonanza and Baron owners," said Andy Cebula, AOPA senior vice president of Government and Technical Affairs.
"However, this adds more pressure on the FAA to examine aging aircraft issues in the general aviation fleet. Some of the T-34s have a much greater number of fatigue cycles than the typical GA aircraft. From the FAA's viewpoint, the problems they are having could be an advance indicator of issues that will face other aircraft in the next decades.
"Our number one priority is maintaining the safety of our aircraft," Cebula said. "But consistent with safety, we also will continue AOPA's advocacy to keep these aircraft affordable and flying."
The FAA's Emergency AD 2004-25-51 grounds all T-34s until they can be inspected or modified under a program approved by the FAA's Wichita aircraft certification office (ACO). However, investigators don't know yet exactly what caused the left wing to fail, so there is no approved inspection program at this time. The T-34s will be grounded for an indefinite period.
The AD does allow owners to fly their aircraft back to home base or to a maintenance facility. For that purpose, owners may fly the aircraft for up to 10 hours within the next 30 days, provided they do so in VFR conditions, do not exceed 152 knots, and don't impose any loads on the aircraft greater than normal-category flight (-0 to +2.5 G).
The Texas T-34 that broke up was an early model (serial number G-13). The FAA says that, according to maintenance records, it was in compliance with AD 2001-13-18 R1. That AD was issued after the 1999 in-flight wing separation of another T-34 engaged in mock aerial combat. It calls for various repetitive wing spar inspections. Approved alternate means of compliance (AMOC) can eliminate some of the repetitive inspections.
In this case, the aircraft owners had satisfied the AD by installing a used Baron wing spar, as allowed under one of the AMOCs. While it was legal to install a used spar at that time, currently only new spars may be installed to satisfy the AD.
In this accident, the left wing center section failed four inches inboard of the forward wing attach fitting. That's inboard from the replacement Baron spar, which did not fail. That's also an area not covered by the existing AD. The FAA reports that there was visual evidence of metal fatigue in other areas not covered by the AD.
Because of the way this aircraft was used, investigators will have more information to work with than is the case with many GA accidents. The T-34 was equipped with three cameras to record the customer's flight. The videotape of the accident flight was recovered and may yield additional clues.
AOPA has worked in concert with the T-34 Association to find cost-effective ways to keep these classic aircraft flying safely. In particular, AOPA has argued that T-34s used in aggressive aerobatic flight should be treated differently than aircraft flown in the normal category.
For more information, see AOPA's regulatory brief.
December 14, 2004