The fatal crash of a homebuilt Zodiac CH-601XL last month has prompted the FAA to freeze the issuance of new airworthiness certificates for the design. The accident was the sixth attributed to an in-flight break up.
The timing of the crash is poignant, as it came one day before the FAA issued a Special Airworthiness Information Bulletin concerning aerodynamic flutter that may have been a factor in the accidents.
“There have been too many crashes. We think one crash is too many,” said Sebastien Heintz, president of Zenith Aircraft, which manufactures the kits. His father, Chris Heintz, is the designer of the aircraft. “The frustrating thing is that there is no single cause that was responsible for all the accidents.”
On Nov. 6, a Zodiac CH-601XL was destroyed as a result of an in-flight breakup near Agnos, Arkansas, killing the pilot. Both wings separated from the fuselage in-flight.
In April, the NTSB called on the FAA to ground all Zodiac CH-601XLs after it linked six accidents, which killed 10 people, to aerodynamic flutter, a phenomenon in which the control surfaces and wings can suddenly oscillate and lead to catastrophic structural failure. Preliminary investigation of the Arkansas accident reveals a failure mode similar to that seen in the earlier crashes, NTSB officials report.
Since April, the NTSB and the FAA have been conducting a special review of the Zodiac CH601XL and the similarly designed CH650 to evaluate design and operational details of the aircraft. The SAIB is the result of that review.
Heintz noted his company is working closely with the FAA and the NTSB on the issue.
“We are taking a very pro-active approach in that we have introduced a full upgrade package,” he said. “It beefs up the entire airplane.”
As this issue was going to press, the company was in the process of finalizing the upgrade package.
“We are making the upgrade package available to all builders and owners to meet the FAA’s recommendations as soon as possible and at minimum inconvenience and cost,” said Heintz. “We think it will cost about $400, which is fairly inexpensive.”
According to Heintz, the package is designed to strengthen the airplane by over-building the wing spars and adding aileron counter-balance.
“We strongly believe that implementation of the comprehensive upgrade package kit, combined with continuing pilot education and training, as well as an ongoing airworthiness/maintenance program, will put an end to the type of tragic accidents that have been happening and restore this aircraft’s reputation as a capable and fun Light Sport Aircraft,” he said.
Heintz estimates the upgrade package will take a few weeks to a few months for aircraft owners to apply — “depending on how much they work on their airplanes,” he said.
Heintz noted that within hours of the SAIB being issued the company had information posted on its website to answer customer’s questions.
“We have also been taking a lot of phone calls,” he said. “We have customers around the world and we have been here for them. We are talking to them and they have been very supportive.”