Narrative:

I understand that the sim is not the airplane. However, the check airman showed us something I think could be serious. He put us at the marker configured for landing single engine, gear down, flaps 20, rudder adjusted properly. He failed the APU, so we were down to 1 electrical source. During the approach, the aircraft became uncontrollable. We tried it again and put out the RAT this time, to a happy ending. If the sim is similar to the aircraft, this could be a serious problem and should be in the book that in case of APU not start (or placarded inoperative) to put out the RAT. It is not there now, and a serious accident could take place without warning. Callback conversation with reporter revealed the following information: the reporter discussed the ramifications of an engine failure on the electrical and hydraulic systems of the B757. Among other system anomalies, one of the two electric pumps for the center hydraulic system (one of three systems) is shut down. The simulator demonstration showed a loss of both rudder and aileron authority to the point of loss of aircraft control. The check airman demonstrated that deploying the 'RAT' (ram air turbine [air driven hydraulic pump]) would provide ample additional hydraulic authority to return normal control response. He strongly noted that RAT deployment is 'not' part of any engine fail procedure checklist. Reporter did acknowledge the apparent dichotomy of the lack of any such simulator flight control problems during engine failure at takeoff procedures, which are routinely flown to 1500 ft or more before any checklist procedure is initiated. The requirement to start the APU (noted as 'if available') is not part of the immediate action steps of such a procedure and is only part of 'time permitting' or 'reference action' steps. Thus, the starting of the APU could well not be initiated until several minutes after the engine failure.

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Original NASA ASRS Text

Title: A B757 CAPT RPTS THAT COMPANY TRAINING CHECK AIRMEN ARE DEMONSTRATING A LOSS OF AILERON AND RUDDER CTL AUTHORITY ON APCHES WHEN AN ENG FAILS AND THE APU IS NOT AVAILABLE TO ALLOW FULL ELECTRIC CTR HYDRAULIC SYSTEM CAPABILITY. THIS DEMO IS DONE IN THE SIMULATOR AND AUTHORIZED BY THE COMPANY. NONETHELESS, HIS COMPANY DISPATCHES THESE ACFT WITH INOPERATIVE APU'S AND WITH NO FAA APPROVED PROC TO COMPENSATE FOR THIS SHORTCOMING.

Narrative: I UNDERSTAND THAT THE SIM IS NOT THE AIRPLANE. HOWEVER, THE CHECK AIRMAN SHOWED US SOMETHING I THINK COULD BE SERIOUS. HE PUT US AT THE MARKER CONFIGURED FOR LNDG SINGLE ENG, GEAR DOWN, FLAPS 20, RUDDER ADJUSTED PROPERLY. HE FAILED THE APU, SO WE WERE DOWN TO 1 ELECTRICAL SOURCE. DURING THE APCH, THE ACFT BECAME UNCONTROLLABLE. WE TRIED IT AGAIN AND PUT OUT THE RAT THIS TIME, TO A HAPPY ENDING. IF THE SIM IS SIMILAR TO THE ACFT, THIS COULD BE A SERIOUS PROB AND SHOULD BE IN THE BOOK THAT IN CASE OF APU NOT START (OR PLACARDED INOP) TO PUT OUT THE RAT. IT IS NOT THERE NOW, AND A SERIOUS ACCIDENT COULD TAKE PLACE WITHOUT WARNING. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR DISCUSSED THE RAMIFICATIONS OF AN ENG FAILURE ON THE ELECTRICAL AND HYDRAULIC SYSTEMS OF THE B757. AMONG OTHER SYSTEM ANOMALIES, ONE OF THE TWO ELECTRIC PUMPS FOR THE CTR HYDRAULIC SYSTEM (ONE OF THREE SYSTEMS) IS SHUT DOWN. THE SIMULATOR DEMO SHOWED A LOSS OF BOTH RUDDER AND AILERON AUTHORITY TO THE POINT OF LOSS OF ACFT CTL. THE CHECK AIRMAN DEMONSTRATED THAT DEPLOYING THE 'RAT' (RAM AIR TURBINE [AIR DRIVEN HYDRAULIC PUMP]) WOULD PROVIDE AMPLE ADDITIONAL HYDRAULIC AUTHORITY TO RETURN NORMAL CTL RESPONSE. HE STRONGLY NOTED THAT RAT DEPLOYMENT IS 'NOT' PART OF ANY ENG FAIL PROC CHECKLIST. RPTR DID ACKNOWLEDGE THE APPARENT DICHOTOMY OF THE LACK OF ANY SUCH SIMULATOR FLT CTL PROBS DURING ENG FAILURE AT TKOF PROCS, WHICH ARE ROUTINELY FLOWN TO 1500 FT OR MORE BEFORE ANY CHECKLIST PROC IS INITIATED. THE REQUIREMENT TO START THE APU (NOTED AS 'IF AVAILABLE') IS NOT PART OF THE IMMEDIATE ACTION STEPS OF SUCH A PROC AND IS ONLY PART OF 'TIME PERMITTING' OR 'REFERENCE ACTION' STEPS. THUS, THE STARTING OF THE APU COULD WELL NOT BE INITIATED UNTIL SEVERAL MINUTES AFTER THE ENG FAILURE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.