19th Jun 2012, 19:31
Doing some TRUCE today at work (not much else to do where I am at the moment...) and read the following report:
Surprised not to have seen this discusssed on PPrune and would welcome any thoughts on it from yourselves. Double bounce, reversers deployed, low energy, high drag GA, cross wind.... Quite a mixture!:eek: As an ATCO, I'd be interested to know what the tower called when they hit the crash alarm - Full Emergency or Aircraft Accident Imminent?
From top slot, re' AAIB's analysis of approach-landing ARC-tail, A306/10Jan2011, East Midlands:
"... not ... discussed on PPrune ... welcome any thoughts ... Double bounce, reversers deployed, low energy, high drag GA, cross wind...."
THANKS -- I'll add that AAIB analysis to the files: Appch/Ldg mishap, ARC-tail.
This 10Jan2011 mishap could be filed as a G/A mishap, or a Bounced Ldg, or Low Energy (idle) ARC. Mostly, investigators have found such cases too difficult for comprehensive analysis, but AAIB does much better than NTSB.
Lndg-ARC's included: hard (heavy), bounced, tail-, or wingtip- strike: whether the strike is Tail or Wingtip, they share common factors:
http://www.pprune.org/tech-log/446935-ups-a306-hard-landing-kabq.html , still awaiting NTSB's "docket" and "final".
http://www.pprune.org/tech-log/350693-vref-landing-4.html , slot 61, 70, 73.
http://www.pprune.org/rumours-news/451705-american-md-83-lga-wing-tip-contact-may-5-2011-a.html , slot #11.
Re' G/A with a ThRev in-transit:
PacWest 314 / 11Feb78, B737-275, C-FPWC, Cranbrook BC. ... flew ILS Rwy 16, touched-down on runway, selected Reverse Thrust, pilot immediately elected to Go-Around due to snow removal equipment on runway. The engine thrust reverser on the left engine did not fully re-stow because hydraulic power was automatically cut off at lift-off.
“Reverse thrust was cancelled immediately after touchdown and a go-around was initiated. The aircraft became airborne prior to the 2000 foot mark, and flew down the runway at a height of 50 to 70 feet, flying over a snow removal vehicle which was still on the runway, 2050 feet from the threshold and 20 feet from the right edge. About this time the left engine thrust reverser doors deployed. A few seconds later the flap was selected up from 40 degrees to 15 degrees. The landing gear remained down and locked. Six seconds before impact and just over 4000 feet from the runway threshold, the flight recorder data indicates that a large amount of left rudder was momentarily applied [note 2 The validity of this FDR indication is in question...]. The aircraft climbed to 300 to 400 feet above the airfield, banked steeply to the left, lost height and side-slipped into the ground to the left of the runway. Fire broke out on impact.” [AAR pg 2]
Pilots lost control of the aircraft consequent upon the left engine thrust reverser deploying in flight when the aircraft was at low speed, and in a high drag configuration. Considerable yaw to the left occurred about 6 seconds before impact and caused a roll to the left....
Analysis, section 2.6, “The Loss of Control” – “The go-around would no doubt have been successful if the left engine thrust reverser doors had not deployed. This occurred because the retraction cycle was interrupted at lift-off by a feature of the design which caused hydraulic power to be removed from the thrust reverser door mechanism....”
Analysis Pg 37: “The flight data recorder record indicates that left rudder was applied 6 seconds before impact, about the time that the flap lever was moved to “15”. Such a rudder application would start a yaw and roll to the left at a critical phase of the flight. The validity of this data point showing a heavy, brief application of left rudder must be called into question ... if the 20 degrees of left rudder had been applied as indicated by the FDR, the aircraft, which was at only 100 ft above the ground at that moment, would have struck that ground within two or three seconds.... Full details of the actions in the cockpit and the reactions of the aircraft in those final six seconds will probably never be known, due to loss of recorded data. There is however no doubt that a considerable yaw to the left occurred about 6 seconds before impact and caused a roll to the left. The pilots attempted to counter this yaw and roll at 4 seconds before impact with full right aileron and rudder at the same time pulling back on the control column. The aircraft, then being below minimum control speed went out of control and rolled 90 degrees to the left....”
Conclusions (Findings) [AAR pg 40] = “3.1... estimated time of arrival .... used by Aeroadio ... considerably in err ... resulted in a traffic conflict between the arriving aircraft an a vehicle working on the runway.”
Distracted crew failed to report the Skookum beacon inbound. FDR and CVR were damaged, but some data was recovered from the Data Recorder.
[Canadian AAR# H80001, 41pages + addition appendixes excerpted from other sources.]