Excel-Jet Ltd. has filed suit against the FAA over the crash of the company’s Sport-Jet prototype last June at the Colorado Springs Municipal Airport.
In its filing, the Colorado Springs-based company claims air traffic controllers caused the June 22, 2006, crash when the plane was cleared for takeoff behind a de Havilland Dash-8-200 in violation of mandatory separation requirements. When the Sport-Jet encountered wake turbulence from the Dash 8, it suffered a violent, uncommanded roll immediately after lift off and crashed, Excel-Jet officials claim. Test pilots James Stewart and Ron McElroy suffered minor injuries.
The company had “no option but to take this action to prove that there was no fault with the aircraft or pilot,” said Bob Bornhofen, president.
“Test pilots James Stewart and Ron McElroy had accumulated 24 hours of virtually flawless flight testing,” he said. “The Sport-Jet had explored the majority of its flight envelope without problems.”
Bornhofen believes the ATC clearance of the Sport-Jet was in violation of the FAA’s regulations “and caused it to crash,” according to lawyer Frank Coppola.
In its filing, the company cites the Air Traffic Control Manual, which states that controllers “should separate small aircraft taking off from an intersection on the same runway behind a preceding departing large aircraft by ensuring the small aircraft does not start takeoff roll until at least three minutes after the large aircraft has taken off.”
In a previous interview with General Aviation News, test pilot Stewart said the clearance came one minute and 28 seconds after the Dash 8 took off. When he got his clearance, he began his takeoff roll immediately, he said.
Excel-Jet has retained experts to review the accident and their analysis concludes there was no fault with the aircraft or the pilot, according to company officials.
“The focus is on ATC procedures and operations and wake turbulence,” a company announcement about the lawsuit states. However, the company’s position disagrees with a preliminary report from the National Transportation Safety Board, which conducted its own wake turbulence study.
Using an engineering numerical model of the behavior of aircraft trailing vortices, NTSB researchers computed a “snapshot” of the Dash-8 wake vortices at the time of the accident, according to the safety board’s report. Using Airport Surveillance Radar data, investigators determined that the Sport-Jet was in the same position on the runway that the Dash-8 had been in two minutes and 11 seconds earlier.
The study concludes, “Even slight turbulence in the atmosphere would have caused the circulation of the vortices within 0.25 nautical miles of the accident to decay to zero within two minutes.
“Given the time of day of the accident, consistent reports of easterly surface wind speeds on the order of 6 to 7 knots, higher wind speeds aloft, and the mountainous terrain near Colorado Springs, it is unlikely that the atmosphere was quiescent enough to allow the wake vortices to retain any significant circulation after two minutes.
“Furthermore, easterly surface winds would have blown the wake vortices well to the west of the runway by the time of the accident. Consequently… it is most likely that the wake vortices were neither strong enough nor close enough to cause the violent roll to the left reported by the witnesses to the accident.”
“We think the NTSB conclusion is wrong,” responded Coppola, Excel-Jet’s lawyer.
The company has asked for compensatory damages for the loss of its property, as well as loss of business and profits. No dollar figure was set in the filing, which also asks for “other and further relief as the court deems just and proper.”
An FAA spokesman said the agency does not comment on pending litigation, but did refer to the NTSB report.
Meanwhile, the company continues work on the second prototype of the Sport-Jet, which is a single-engine, four-place jet, powered by a Williams FJ-33 engine. Sport-Jet, which is priced at about $1.2 million, is expected to cruise at 380 knots at 28,000 feet, and carry four people for more than 900 nautical miles.