The US Federal Aviation Administration (FAA) has launched a special review of the structural design and flutter characteristics of certain Zenair Zodiac CH-601 XL aircraft models in response to several recommendations on the type issued by the National Transportation Safety Board (NTSB) in April.
The agency however stopped short of the NTSB’s call to ground the experimental and factory-built light sport aircraft (S-LSA) versions of the low-wing two-seater.
In a 13 July letter to the NTSB, FAA administrator Randolph Babbitt writes that the FAA “lacks adequate justification” to ground the CH-601XL models, per the NTSB’s request. “Data indicates the CH-601XL has a safety record similar to other S-LSA and appears capable of safe flight and operations if maintained according to the manufacturer’s recommendations,” Babbitt continues.
NTSB investigators have determined that flutter and other related factors are suspected as factors in six CH 601 XL crashes that have killed 10 people in Europe and the USA since 2006.