The NTSB issued recommendations that the FAA revise birdstrike certification requirements and more carefully monitor charter operators following the Board’s determination of the probable cause of a
birdstrike crash in Oklahoma City last year. The crash occurred on March 4, 2008, about two minutes after a Cessna Citation 500 registered to Southwest Orthopedic & Sports Medicine took off from Wiley Post Airport. According to the NTSB, “The probable cause of the 2008 crash…was airplane wing-structure damage sustained during impact with one or more large birds…which resulted in a loss of control of the airplane.” All on board–two pilots and three passengers– were killed in the crash.

In its investigation of the accident, the NTSB found that the Citation collided “with a flock of American white pelicans, which far exceeded the airframe’s design certification limit.” The Safety Board also claimed it found that the operator was conducting an illegal charter with the Citation. “At the time of the accident, Interstate Helicopters was operating the accident airplane in commercial service contrary to its [FAA]-issued…Part 135 operating certificate, which, at the time, did not authorize operation of the accident airplane or any other fixed-wing aircraft.”

The NTSB noted that neither pilot was qualified to fly under Part 135, nor was the Citation maintained in accordance with Part 135. Interstate Helicopters, which did hold a Part 135 certificate for helicopters at the time of the accident, disguised fixed-wing charter flights by labeling invoices as “aircraft lease” and “sales demo” flights, according to the NTSB, “circumventing the terms of its operating certificate.”

In September 2008, the FAA revoked Interstate’s Part 135 certificate on an emergency basis, but company founder and president Jim Johnson appealed the revocation, and the FAA agreed to expedite Interstate’s reapplication for a new certificate if Johnson dropped the appeal. The FAA issued a new Part 135 certificate about four months later, although only for a single-pilot operation.

Johnson said that Interstate was leasing the Citation to the customer, United Engines and United Holdings. “That flight never started out to be a charter,” he told AIN, adding that the company never claimed to have a fixed-wing charter certificate. According to the NTSB, the FAA’s Oklahoma City flight standards district office had made a two-hour on-site inquiry at Interstate after receiving a complaint about the company and didn’t detect any improper charter activity. The FAA also had conducted a special emphasis inspection focusing on operational control, and that “inspection was insufficient to detect the type of noncompliant charter operations that were conducted by Interstate Helicopters,” the NTSB said.

Although the NTSB placed much emphasis on what it said was a noncompliant charter, Johnson noted that the pilots were properly trained for the flight they were conducting and that no amount of Part 135 company procedures and paperwork training would have helped the pilots handle the birdstrike any differently.

The Safety Board concluded that birdstrike airframe certification standards are insufficient “because they are not based on birdstrike risks to aircraft derived from analysis of current birdstrike and bird-population data and trends.” The airport also had failed to conduct a required wildlife hazard assessment, the NTSB wrote, and that failure “prevented the determination of what mitigation measures, if any, could have been implemented to reduce the risk of an in-flight collision with American white pelicans.”

Something else that might have helped, the NTSB added, would be reference charts in the pilot’s handbook “that depict both the airspeeds at which the airframe can sustain strikes from various-sized birds without exceeding certification standards and minimum safe airspeeds [that] could help pilots devise precautionary operational strategies for minimizing potential airframe birdstrike damage in high-risk areas for birdstrikes.” The NTSB also wants the FAA to make birdstrike reporting mandatory to “improve the quality of the data in the FAA National Wildlife Strike Database.”

Family members of the passengers who died in the crash have sued Interstate Helicopters.