Pilot lost grip on control yoke before 767 freighter’s hard nose-gear impact

Sharp derotation that badly damaged fuselage occurred after captain blocked control column to avoid excessive nose-up attitude.
US investigators believe neither pilot had control of a Boeing 767-300 freighter’s pitch when it sharply derotated on landing at San Bernardino, the hard nose-gear touchdown wrinkling its fuselage.

The aircraft – operated by Air Transport International, and branded in the livery of retailer Amazon – had been arriving from Spokane on 15 January this year, with the first officer flying the ILS approach to runway 6.

As the aircraft touched down, it tended to pitch up, and the first officer relaxed the control yoke and applied forward pressure.

But the captain felt the aircraft was over-rotating and, concerned about a potential tail-strike, used his hand to block the control yoke from moving further aft.

The first officer testified that the yoke “abruptly and forcefully” moved forward, causing him momentarily to lose his grip, and the aircraft rapidly derotated.

“While the first officer recalled that the controls moved abruptly forward while he was at the same time already moving it forward, the captain recalled putting his hand up to prevent further movement of the control column aft,” says the National Transportation Safety Board.

“The investigation was unable to resolve this discrepancy definitively.”

But it says the first officer did not realise the captain was restricting the aft yoke movement, and the captain – who was watching the runway – did not see that the first officer’s hands had slipped from the yoke.

“They discovered this during their after-landing conversations, and concluded that, for a period of time, apparently neither one of them [was] on the controls,” says the inquiry.

“Review of the recorded data could not definitively confirm when, or for how long, the pilots had their hands off the control yoke.”

The inquiry points out that this inadequate communication between the pilots on pitch control inputs, and lack of situational awareness regarding the yoke, contributed to the accident.

“There was no verbal communication between the crew recorded on the [cockpit-voice recorder] at the time of the captain’s intervention, or the first officer’s loss of grip on the yoke,” it states.

Flight-data recorder analysis shows the 767 touched down at 124kt, while 5° nose-up. The control column, positioned about 12° aft, initially reduced to 6°, lowering the nose.

But the column then moved to 20° aft before it “immediately reversed” to 20° forward in the space of 1.5s, says the inquiry.

This resulted in the aircraft’s pitching from 3° to 6° nose-up before the sudden derotation to zero – resulting in a 1.6g impact as the nose-gear made runway contact.

Examination of the 767 – a 1992 airframe registered N443AZ – revealed that it had sustained considerable damage to the crown of the upper fuselage, which was buckled and fractured, damage which extended to the underlying stringers, lap and butt joints. Neither pilot was injured.

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