FLC OF ADVANCED LGT EXCEEDED SPDS; ALTS; AND PWR SETTINGS ON SNA NOISE ABATEMENT SID.
Synopsis
FLC OF ADVANCED LGT EXCEEDED SPDS; ALTS; AND PWR SETTINGS ON SNA NOISE ABATEMENT SID.
Narrative
MAX PWR 1.42 EPR TKOF WAS MADE USING THE AUTOTHROTTLE. FLT DIRECTOR WAS OFF BECAUSE NORMAL TKOF PITCH COMMAND OF 17.5 DEGS WAS BELOW THE QUIET PROFILE TARGET PITCH OF 25 DEGS REQUIRED TO MAINTAIN V2+15. AT APPROX 800 FT ON THE SPECIAL SNA NOISE ABATEMENT PROFILE; A SPECIAL PRESELECTED QUIET CLB #2 EPR OF 1.25 USING THE TMSP THRUST MODE SELECTOR PANEL IS MANUALLY PUSHED BY THE PNF TO COMMAND THE AUTOTHROTTLE TO AUTOMATICALLY SET THAT PWR. THE PF NEEDS TO IMMEDIATELY LOWER THE PITCH FROM 25 DEGS TO 15 DEGS TO STAY ON PROFILE AND MAINTAIN V2+15 AND CONTINUES THE SID DEP CLB TO 3000 FT AS ASSIGNED BY ATC. IN ADDITION TO THESE NONSTANDARD PWR AND PITCHES; YOU ARE TO TRACK OUTBOUND ON THE BACK COURSE LOC TO THE 1 DME FIX AND TURN TO THE 175 DEG HDG. IT WAS A DARK AND STORMY NIGHT. THE CAPT REACHING ACROSS THE COCKPIT IN TURB PUSHED THE WRONG BUTTON ON THE TMSP/AUTOTHROTTLE. THE LARGE REDUCTION IN PWR FROM MAX 1.42 TO QUIET 1.25 DID NOT TAKE PLACE. NORMAL CLB PWR OF 1.35 WAS SET AND CRZ WAS DISPLAYED ABOVE THE EPR SYMBOL ON THE EICAS ENG INDICATING CAUTION ADVISORY SYS. AT QUIET PROFILE PITCH OF 15 DEGS THE AIRSPD AND RATE OF CLB BECAME EXCESSIVE. PWR WAS FIRST MANUALLY REDUCED AND THEN MANUALLY DISCONNECTED USING THE AUTOTHROTTLE DISCONNECT BUTTON; WHICH CAUSED A WARNING ON THE MASTER CAUTION AND EICAS SYS. WITH LITTLE OR NO TIME FOR RECOGNITION; REACTION; OR RECOVERY; WE HAD OUR HANDS FULL TRYING TO MAKE THE LEVEL OFF AT 3000 FT AT AN AIRSPD BELOW 250 KTS. CREW PROFICIENCY IS DIFFICULT IN A PROFILE THAT IS RADICALLY DIFFERENT FROM STANDARD. THERE IS NO ROOM FOR ERROR UNDER NORMAL CONDITIONS AND IS UNSAFE IN ABNORMAL SITUATIONS. UNDER NONSTANDARD PROCS; THE AUTOMATED SYS WERE NEVER DESIGNED FOR; WORKLOAD IS INCREASED. I WOULD RECOMMEND ONLY MINOR CHANGES TO THE NORMAL TKOF PROFILE OR FLY THE ENTIRE PROC USING RAW DATA WITH ALL AUTOMATED SYS MANUALLY SET. I HAVE ALMOST A YR ON THE LGT AND ALMOST 2 YRS ON ANOTHER ACFT BEFORE THAT. THE AUTOMATION IS GREAT UNDER NORMAL CONDITIONS AND WORKS WELL WHEN YOU HAVE THE TIME TO MONITOR. WHEN THERE ISN'T THE TIME TO MONITOR; YOU NEED TO FLY THE AIRPLANE WITHOUT DELIBERATELY TRYING TO OVERRIDE SYS THAT WERE NEVER DESIGNED TO PERFORM THESE NONSTANDARD TKOF PROFILES.
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Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.