Turbine engines are extremely reliable and many business jet pilots go through their entire careers experiencing engine failures only during simulator training. But in mid-July, two Beechjet 400A pilots found out what it’s like to lose not just one engine in flight, but both of them. Fortunately for them and their seven passengers they were able to get one of the light jet’s engines restarted during the descent.
Safety analyst Robert Breiling of Robert E. Breiling Associates said dual flameouts are “very rare.” He added, “There have been only four or five such incidents in the history of business jets.”
According to the NTSB’s preliminary report of the recent incident, at about 1210 EDT on July 12, both engines of a Beechjet 400A operated by fractional provider Flight Options flamed out while the airplane was descending from FL410 to FL330 over the Gulf of Mexico about 100 miles west of Sarasota, Fla. The NTSB said the airplane (N455CW) was operating on an IFR flight plan under Part 135 (although Flight Options disputes the latter point) from Duncan, Okla., to Fort Myers, Fla.
The preliminary report states that the airplane was cruising in instrument conditions at FL410 when ATC cleared the crew to descend. The pilots said that after they initiated the descent they felt a jolt and heard a bang.
About 30 seconds later, the pilots realized the airplane was losing cabin pressure. They then declared an emergency and went through the emergency-descent checklist.
At about FL350, the crew “noticed that every cockpit warning light was illuminated and that both engines were not operating.” After several attempts, they were able to get the number-two engine restarted at about 14,000 feet and elected to divert to Sarasota because it was relatively close. The aircraft landed safely, and the two pilots and seven passengers were not injured. Flight Options said the passengers aboard the aircraft continued on to their destination, but would not say by what mode.
Initial examination of the Beechjet’s Pratt & Whitney Canada JT15D-5 turbofans has revealed no mechanical anomalies, according to the NTSB. To date, the JT15D family has accumulated about 34 million operating hours, and the in-flight engine shutdown rate is .005 per 1,000 hours. Besides the Beechjet, the engine model is also on several other business aircraft, such as the Citation 500, II, V and Ultra; and the Mitsubishi Diamond, the Beechjet’s predecessor.
At press time, the Safety Board was still analyzing fuel samples taken from both the Beechjet and the last location where the aircraft uploaded fuel before the incident. Raytheon Aircraft and Pratt & Whitney Canada declined comment, citing the ongoing NTSB investigation.