|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Locale Reference||airport : zzz.airport|
|Operator||common carrier : air carrier|
|Make Model Name||L-1011 Tri-Star All Series|
|Operating Under FAR Part||Part 121|
|Route In Use||approach : instrument non precision|
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : flight engineer|
pilot : atp
|Experience||flight time last 90 days : 60|
flight time total : 9000
flight time type : 4000
|Affiliation||company : air carrier|
|Function||observation : company check pilot|
|Anomaly||altitude deviation : overshoot|
non adherence : published procedure
other anomaly other
|Independent Detector||other flight crewa|
Flight Crew Human Performance
Constant angle non-precision approach procedure. Attached are 2 docs. 1 doc is a letter of concern I wrote to my company's director of standards and training, copied to our vice president of flight operations expressing my concerns about our conduct of this procedure and the procedure in general. I have received no response from either of them. I did discuss this with our local FAA, and they saw my point, but felt that it was up to the company to decide their policy and then the FAA would either approve or disapprove the procedure. The other doc is a detail of the procedure from our B757 fleet manager. I will state here that I do not believe allowing descent to MDA without the protection of arming the MDA on the MCP is safe. The argument has been made that one doesn't 'arm' decision altitude on an ILS. While that is true, the counter to that argument is if you do not go around (for whatever reason) while conducting an ILS, you will end up on a runway. A very hard landing, mind you, but a landing on the runway nonetheless. The same cannot be said for a non-precision approach. I find it even more inconsistent that our procedures require us, when setting a new altitude on the MCP, that the new altitude be verified set and armed by both pilots, and that both pilots must point to the new altitude set in the window. If it is important enough to do at FL350, then I would think it even more important when only a few hundred ft above the ground.
Original NASA ASRS Text
Title: A PROPOSED PROC FOR 'CONSTANT ANGLE NON PRECISION APCH PROC' IS QUESTIONED BY AN ACR PLT. STABILITY OF THE APCH AND POSSIBLE OVERSHOOT OF MINIMUM DSCNT ALTS BECAUSE OF THE CAPABILITY OF THE L-1011 AUTOFLT CAPABILITIES ARE CITED AS PROBS.
Narrative: CONSTANT ANGLE NON-PRECISION APCH PROC. ATTACHED ARE 2 DOCS. 1 DOC IS A LETTER OF CONCERN I WROTE TO MY COMPANY'S DIRECTOR OF STANDARDS AND TRAINING, COPIED TO OUR VICE PRESIDENT OF FLT OPS EXPRESSING MY CONCERNS ABOUT OUR CONDUCT OF THIS PROC AND THE PROC IN GENERAL. I HAVE RECEIVED NO RESPONSE FROM EITHER OF THEM. I DID DISCUSS THIS WITH OUR LCL FAA, AND THEY SAW MY POINT, BUT FELT THAT IT WAS UP TO THE COMPANY TO DECIDE THEIR POLICY AND THEN THE FAA WOULD EITHER APPROVE OR DISAPPROVE THE PROC. THE OTHER DOC IS A DETAIL OF THE PROC FROM OUR B757 FLEET MGR. I WILL STATE HERE THAT I DO NOT BELIEVE ALLOWING DSCNT TO MDA WITHOUT THE PROTECTION OF ARMING THE MDA ON THE MCP IS SAFE. THE ARGUMENT HAS BEEN MADE THAT ONE DOESN'T 'ARM' DECISION ALT ON AN ILS. WHILE THAT IS TRUE, THE COUNTER TO THAT ARGUMENT IS IF YOU DO NOT GO AROUND (FOR WHATEVER REASON) WHILE CONDUCTING AN ILS, YOU WILL END UP ON A RWY. A VERY HARD LNDG, MIND YOU, BUT A LNDG ON THE RWY NONETHELESS. THE SAME CANNOT BE SAID FOR A NON-PRECISION APCH. I FIND IT EVEN MORE INCONSISTENT THAT OUR PROCS REQUIRE US, WHEN SETTING A NEW ALT ON THE MCP, THAT THE NEW ALT BE VERIFIED SET AND ARMED BY BOTH PLTS, AND THAT BOTH PLTS MUST POINT TO THE NEW ALT SET IN THE WINDOW. IF IT IS IMPORTANT ENOUGH TO DO AT FL350, THEN I WOULD THINK IT EVEN MORE IMPORTANT WHEN ONLY A FEW HUNDRED FT ABOVE THE GND.
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.