Analysis
The Captain (Age 41, 7,000hrs on 737 but only 72hrs on 737-800) was PF. The F/O (Age 25, 1,400hrs TT). The aircraft, at the time of the accident, landed with an estimated mass of 64,427 kg.
The latest ATIS was as follows:
VOR05 Approach Wind VRB03KT 9999 BKN1600 17/11 1017 RS080/03KT 05110/03KT 23080/05KT
But a wind check 2 minutes before the incident was as follows:
Wind 350 220V020/13KT gusting 24KT runway 05
Funchal Airport
For those pilots who dont know Funchal airport, It is a Category C airport due to its proximity to terrain which means that it does not have an ILS and turbulence can be expected in high winds. The airfield briefing states:
"The Airport is located on a plateau on the East coast of Madeira Island. Except for the seaside, ground raises rapidly very closed to it. This fact generates, very often, wind variation and turbulence. Also severe low altitude wind shear conditions and/or micro burst are likely to be encountered. "
Damage to G-GDFC (Photo GPIAA Report)
The crew had been expecting turbulence from the TAF and METARs but the wind was within limits for the approach. The aircraft had held before commencing the approach due to traffic congestion. The aircraft that landed ahead reported turbulence in the last 150 feet. The approach was smooth and stable until 100ft when moderate turbulence was encountered with no apparent aircraft drift. The trunulence increased in intensity until at a height of around 30 feet and, simultaneously, a significant sink of the aircraft rapidly developed resulting in a firm landing at approximately 1000 feet beyond runway 05 threshold and about 5 feet left of the runway centerline followed by a shallow but prolonged bounce. It was decided not to perform the go-around with the presence of the downdraft but instead attempt to maintain the aircraft attitude with external visual references. The crew did not consider the pitch attitude of the aircraft to present a tail strike risk so a slight flare was performed before the second contact with the runway which was again firm. The contact occurred near the intersection with taxiway “C” and approximately 15 feet left of the runway centerline.
The aircraft touched in the initial touchdown at 154 knots with 6.1° of nose up pitch and a peak normal acceleration of 1.86g. The recorded left and right engine N1 at touchdown were 40% and 36% respectively. The speedbrakes were not armed before initial touchdown but was manually deployed during the bouncing and shortly before the second touchdown. The highest recorded radio altimeter height in this period was 8 feet. During the bouncing the aircraft pitch attitude reduced to 4° then reached a peak of 9.15° nose up after manual spoiler deployment.
Findings
- In the sequence of the event 2 cabin crew members (CCM) sustained injuries in the lumbar region
- From listening to the CVR it was possible to conclude that the Normal Checklist (Landing) was not executed during the approach
- The aircraft approach was conducted in variable wind conditions, both in intensity and direction, which caused an increase in the pilots workload
- The aircraft approach was conducted under turbulence conditions in the last 150 feet and with a crosswind component from the left side
- The rate of descent exceeded the 1000 feet per minute during the final approach up to moments immediately before the flare
- The aircraft deviated above the nominal approach path below 500 feet
- The approach speed exceeded in more than 10 knots the planned approach speed
- Upon the initial contact on the runway surface with the main landing gear, the aircraft bounced to the air and kept flying at a height of approximately 8 feet, for a distance of about 1000 feet and for 4 to 5 seconds. During the bounce, an excessive aft input was commanded in the flight controls resulting in an attitude of about 9.15⁰, which exceeds the safety margin to avoid a tail strike on the runway, and in a second contact with a load factor of 2.15g
- Following the tail strike on the runway surface, the aircraft sustained damage in Section 46, 47 and 48 of the fuselage
Causes
The accident was due to an excessive nose up input after the first contact with the runway and at a time in which the aircraft was airborne at around 8 feet (RA) which, associated to the manual deployment of the speedbrakes and consequent loss of lift, resulted in a sharp nose up attitude (9.15⁰) to a point of causing the tail strike with the runway surface.
Contributing Factors
- The Normal Checklist (Landing) was not executed (737-800 FCOM Chapter NP)
- The aircraft approach was conducted under turbulence conditions in the last 150 feet
- Aircraft deviation from the “stabilized approach” profile which implied the execution of a go-around (737 NG FCTM Chapter 5);
- The judgement not to execute a go-around after the bounce on the runway (737 NG FCTM Chapter 6);
- Speedbrakes manual deployment during the bounce resulting in a loss of lift and nose up pitching moment
SAFETY RECOMENDATIONS
- To issue instructions to the flight crews to strictly adhere to the company SOP´s.
- Review the recency rules regarding B737-800 variant pilots when operating at CAT C airports.
- To incorporate bounced landing recovery training among the B737-800 variant
- To practice the speedbrakes manual deployment in a timely manner, e.g. by firstly identify the attitude and condition of the aircraft, in the event of an automatic deployment failure
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G-GDFC Jet2 737-800 tailstrike on landing
