NTSB examining possible pre-crash break-up of Learjet 60

Investigators are also hoping their inquiry will be aided by a cockpit voice recorder
Evidence suggests that the Learjet 60 that crashed near Palm Beach in Florida on 1 November may have suffered some degree of structural failure prior to slamming into the ground, according to the US National Transportation Safety Board (NTSB).

Investigators also say the aircraft had at one point been equipped with a cockpit voice recorder, though if that equipment was actually on the jet when it crashed remains unconfirmed.

“We do have some indication that the aircraft was breaking up before impact,” NTSB member Thomas Chapman said on 2 November. “We are still seeking to determine that.”

Chapman spoke during the NTSB’s first post-crash briefing, held in West Palm Beach, not far from the crash site in Lake Worth Beach. He stresses the investigation is in its earliest stages and that much remains unknown about what contributed to the incident, while noting that weather is “certainly a factor”.

The aircraft had been passing near or through storms immediately prior to the crash. Purported video of the crash shows the Learjet descending nearly vertically at an incredibly high speed. The crash left a crater that since filled with water.

All nine people on board the jet – seven passengers and two crew – died. One person on the ground suffered a leg injury, says NTSB lead accident investigator Timothy Monville.

The Learjet was operated by Aurora Aviation under the business name Upper Jets. It was flying under Part 135 Federal Aviation Administration rules from Austin-Bergstrom International airport in Texas to North Eleuthera in the Bahamas, Chapman confirms.

At 12:47 Eastern US time, while at 35,000ft, one of the Learjet’s pilots told air traffic controllers that “they were encountering light clear ice which was manageable” and “moderate turbulence” that was causing 700ft altitude deviations, Chapman says.

At the time, the temperature outside the jet was -47°C (-53°F).

“Very soon after, the crew transmitted, ‘We are picking up precipitation’ and requested permission to climb to 37,000ft”, says Chapman.

Controllers approved that request.

“Less than 30 seconds later, a transmission from the airplane announced the descent, followed by a mayday call,” Chapman says.

The broader crash site spans an area roughly 0.5 x 0.4 miles (0.8 x 0.6km), says Monville, but Chapman adds that investigators might “find parts of the aircraft some distances away from the actual impact site”.

Officials confirm the aircraft at one point had been equipped with a cockpit voice recorder. “What we don’t know is if that recorder was still on board,” Chapman says. “Sometimes these things change over time.”

Hundreds of local residents were evacuated due to the crash and have not yet returned to their homes, officials say.

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