US investigators have determined that an executive jet crew commenced take-off without clearance before it passed in front of a JetBlue Embraer 190 that was flaring for touchdown on an intersecting runway.

The serious incursion, during the E190’s approach to runway 04R at Boston at night, was captured on video by a jumpseat occupant in the cockpit.

According to the National Transportation Safety Board the E190 had been cleared to land while the executive aircraft – a Learjet 60 operated by charter firm Hop-A-Jet – had been instructed to line up and wait on runway 09.

But the Learjet proceeded to start its take-off roll without clearance, and the airport’s surface-detection radar alerted the tower controller to the incursion.

Runways 09 and 04R intersect close to the thresholds of each – at distances of just 300m and 270m respectively.

“As we entered the flare after crossing the threshold of [04R] at about 30ft above the ground, I saw an aircraft cross [04R] on runway [09] from our left to right,” the E190 captain told the inquiry.

“I could not estimate the distance from the aircraft as it had passed out of sight in approximately one to two seconds from when we first saw it.”

JetBlue incursion1-c-NTSB

Source: NTSB

Video captured during the E190 approach (upper) shows the Learjet entering the runway (centre) and crossing the centreline (lower)

Alerted by the incursion alarm, the controller ordered the E190 crew to execute a go-around, which was immediately initiated. The captain said the E190 overflew the intersection at about 20ft, behind the departing Learjet.

The E190 jumpseat was occupied by an Airbus A320 first officer who had chosen to take video footage of the approach – using a personal device, in accordance with JetBlue policy – since it was conducted on a clear night.

He was not wearing a headset, and did not hear any air traffic control communications.

But 1min 26s into the video, the nose of the Learjet enters the left edge of the runway just as an automated ‘30ft’ call-out is heard in the E190 cockpit.

The Learjet starts crossing the centreline slightly ahead of a ‘20ft’ call-out, and exits the runway as an E190 crew member remarks, “go around” and a ‘10ft’ call-out is heard.

Boston 04R and 09 intersection-c-Google Maps

Source: Google Maps

Boston’s runways 04R and 09 intersect close to their thresholds

According to testimony given to the inquiry by the Learjet captain – who was the non-flying pilot – the aircraft was being repositioned to Fort Lauderdale, where Hop-A-Jet is based.

He said the aircraft had been cleared to cross the parallel runway 04L and take taxiway M for runway 09.

“Taking taxiway M we had the clearance that seems to be, ‘Line up and wait’, probably,” he said. “I replied back but, on my mind, I was clear for take-off.”

The first officer, who was flying the Learjet, stated that he was concentrating on taxiing the aircraft correctly but remembered the controller’s instructing them to enter the runway.

“As we [lined-up], I asked my work partner if we were cleared for take-off, and [they] said ‘yes’,” he said. “I then proceeded with the take-off procedure.”

After the Learjet became airborne, its crew learned of the incursion incident. The first officer told the inquiry: “We were both convinced that we were cleared for take-off, but that was not the case.”

No-one on board either aircraft (N179JB and N280LJ) was injured during the event.