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Approach and Landing Safety

It is not my intention to purposely identify Air France as a safety culprit when it comes to dodgy approaches to land. But they have certainly been providing the industry with plenty to talk about in recent times. And this is a good thing; not because we like pointing fingers – quite the opposite – but because there is so much to learn through casual discussion of incidents and accidents.

(The benefits of casual discussion are also clear when preparing for six-monthly simulator training sessions, in which all manner of unfortunate and sometimes unpleasant events are thrown as us. Pilots yet to meet their simulated “bad day” question their colleagues, beady-eyed and attentive to the smallest nugget of advance warning, on the ‘events’ handled by those who have already suffered in the recent past. This talking encourages study and formation of opinion and is a critical aspect to the continuous development we must commit to as professional aviators.)

So why have I picked up on Air France?

I will leave the actual judgement and discussion up to you, but I want to identify a couple of common factors in some fairly high-profile approach instability events as reported via avherald.com.

See if you can spot the common factors in each:

  1. High energy approach (too fast or high to safely get on – and stop on – the runway)
  2. Issues with autopilot and a tendency to disconnect it rather than operate it appropriately
  3. Mishandling of the resulting situation
      1. either physical mis-manipulation of the controls, or
      2. improper monitoring of the aircraft systems; no observation by the crew of what the aircraft was screaming at them.

Report: Air France A320 at Tel Aviv on Apr 3rd 2012, approach to stall on turning final results in Alpha Floor and flaps overspeed

Report: Air France A388 at New York on Oct 11th 2010, oversped flaps during go-around

Report: Air France A319 at Tunis on Mar 24th 2012, extreme rate of descent on glideslope intercept, GPWS alerts and descent below safe altitude

Report: Air France B772 at Paris on Nov 16th 2011, continued to descend despite go-around

(As an addition, I have already written about another Air France event on approach to Paris here – false glideslope capture and near stall.)

None of these resulted in injuries. I have paraphrased from the avherald reports.

Tel Aviv

“The pilot flying however felt they were high on the approach but did not share his concern with the pilot monitoring.

“Still in the decent through about 1540 feet the autopilot gets disconnected, flight director and autothrust remain engaged.

“The pilot flying applies nose up inputs for about 10 seconds while the flight director commands nose down inputs to maintain the target speed, the airspeed reduces from 135 KIAS to 122 KIAS with the pitch increasing from 0.7 to 10 degrees nose up, the pilot monitoring later provided testimony that he was monitoring the alignment with the runway. An automatic “Speed, Speed, Speed” call activated at Vapp-16 knots.

“The pilot flying decided to go around but did not call out the go-around. The pilot flying moved the throttle levers into the TOGA detent and applied nose up inputs, the pilot monitoring applied nose down inputs for about 2 seconds (dual input). At that point Alpha Floor protection activated applying TOGA thrust and TOGA Lock, 3000 feet is being selected into the altitude window, open climb mode is being engaged, the speed returns into normal range, the pilots do not detect the “TOGA LOCK” status however. The aircraft climbs through 2000 feet, the crew recognizes difficulties in reducing the thrust. The flaps are selected to 1, the speed increases to 208 KIAS and still continues to increase, 2000 feet and 188 KIAS are being selected into the MCP, the aircraft climbs to 2500 feet before starting to descend again, the speed increased to 223 KIAS (flaps limit 215 KIAS), an overspeed alarm activated.”

New York

“The first officer was pilot flying using the autopilot but did not engage the approach mode. As result the aircraft was above glidepath, the first officer disengaged the autopilot and continued manually.

“At 480 feet AGL the speed was still 210 KIAS and above glidepath about 1nm before the threshold, when the captain, pilot monitoring, ordered a go-around surprising the first officer. The thrust levers were moved to the TOGA detent and initiated a go around, the aircraft quicky assumed a climb rate of about 3400 fpm, pitch attitude about 2 degrees nose up. The first officer moved the thrust levers to the MCT detent, unnoticed by the captain. The aircraft accelerated exceeding the maximum speed for the flaps at position 2, an alert sounded and the flap relief moved the flaps to position 1, about 2 seconds later the flaps were selected to position 1, the vertical speed increased to +4200 fpm. The aircraft climbed through the go-around altitude of 1000 feet, at 1600 feet the first officer attempted a first level off, the speed rose through 301 KIAS. Now the thrust levers were pulled into the CLB detent, which effectively commanded the autothrust into speed mode, the engines were spooled down to idle.”

Tunis

“Upon contacting Tunis approach the controller advised that the active runway had just been switched to runway 19, which shortened the flying distance to land by about 20 nautical miles. The captain briefed for an ILS approach to runway 19 and decided to continue the approach.

“The aircraft descended through FL100 13.5nm before touchdown, the autopilot was disconnected.

“Descending through 3550 feet, 1700 feet above glide, about 5nm from touchdown, flaps still at position 0, vertical speed -4400 fpm, speed brakes and landing gear extended, the first officer (ATPL, 1,700 hours on type) transmitted they were established on the ILS 19. The autothrust was disconnected, the engines were reduced to idle thrust.

“The captain re-engaged autothrust and autopilot.

“The captain stowed the speed brakes and disengaged the autopilot again.

“The thrust levers are placed into the TO/GA detent, the aircraft turns to the left and climbs to 2000 feet, then positions for a visual approach to runway 19 with ILS support.”

Paris (Number 1)

” “Go-around”, the captain responded by pushing the throttles forward to initiate the go-around disconnecting autothrottle in the process. A nose up pitch command on the control yoke is recorded however insufficient in strength to disconnect the autopilot. While the aircraft began to accelerate the attitude changed from +1.15 degrees to -0.5 degrees. The captain ordered the flaps to be reduced to 20 degrees, the pitch decreases further to 2 degrees nose down. The relief pilot called out “Pitch!” 10 seconds after the go-around was initiated both crew pulled the yoke now resulting in the autopilot disconnecting, the aircraft pitched up sharply resulting in +1.84G vertical acceleration, the attitude changed from 2 degrees nose down to 7 degrees nose up and subsequently reducing to 4 degrees nose up when the control yoke was returned to neutral, speed was now 169 KCAS. The relief pilot again called “Pitch!”. The crew applied nose up input on the control yoke, the aircraft reached its lowest point of 63 feet AGL at 180 KCAS, the nose rose to 11 degrees nose up in 2 seconds and subsequently 19 degrees nose up and the aircraft climbed out to safety.”

Paris (Number 2)

“When the aircraft was 9nm before the runway threshold, the aircraft had been established on the localizer however was at 4950 feet MSL about 1750 feet above glideslope. At 4nm before touchdown the aircraft was at 3700 feet MSL: 2100 feet above glideslope, the glideslope indications in the cockpit had already reverted to the side band of the glideslope transmitter (mirror glideslope at 9 degrees).¬†At about 2nm out, the aircraft descended through 2850 feet MSL 1600 feet above glide, the vertical channel of the autopilot mode changed to glideslope capture.

“When the aircraft rotated through 26 degrees nose up, the crew disconnected the autopilot and pushed the side stick forward to near the mechanical stop, the pitch attitude and the rate of climb reduces, the aircraft began to accelerate to 143 KIAS again, the autothrust system disconnected. About 30 seconds later the crew re-engages autopilot 1 and autothrust in climb thrust with the intention to perform an automatic go-around.”

* Note: in the second Paris event, the crew recognised the incorrect flight mode of the autopilot and took control manually once again. This showed good decision-making, ironically saving a situation caused by very poor decision-making in the first place. However, it can be argued that it was exceptionally clear to the crew that the wrong flight modes were engaged, because the aircraft had suddenly nosed over and was now pointing at the earth.

Happy reading and opining.