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|
Attributes | |
ACN | 1129363 |
Time | |
Date | 201311 |
Local Time Of Day | 1201-1800 |
Place | |
Locale Reference | ZZZZ.Airport |
State Reference | FO |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Make Model Name | MD-11 |
Operating Under FAR Part | Part 121 |
Flight Phase | Takeoff |
Component | |
Aircraft Component | Flap Control (Trailing & Leading Edge) |
Person 1 | |
Function | Pilot Flying First Officer |
Person 2 | |
Function | Captain Pilot Not Flying |
Experience | Flight Crew Last 90 Days 89 Flight Crew Total 9999 Flight Crew Type 2500 |
Events | |
Anomaly | Aircraft Equipment Problem Less Severe |
Narrative:
On takeoff; we rejected after getting a 'flaps; flaps' warning around 85 KTS; speed got to around 90 KTS max. Rejected takeoff was uneventful and we notified tower immediately. We had set flaps 10 for takeoff right after start; did our before takeoff checklist; both saw and verified flaps 10 on our pfd's and both saw a green box before takeoff. Flaps were set for takeoff to the minimum setting as per recent guidance from the company; at flaps 10. While a good idea in theory; as it is much less drag should one lose an engine at or after V1; in my opinion this setting can and did possibly result in this rejected takeoff; through a flap transmitter sending an erroneous signal to the flight control computer and giving a false signal that the flaps were less than flaps 10; the minimum setting. On taxiing clear of the runway after the reject; we spoke with maintenance over the sat-phone and it was agreed we should go back to the gate and have local mechanics check out the situation. Never did we see less than flaps 10 on our pfd's until selected so by us after clearing the runway; although right after the reject; I did see my pfd showing an intermittent and back-and-forth flaps 10 changing to flaps 11 annunciation; very rapidly and short in duration. If this signal was ever less than flaps 10 on takeoff; I suspect that this is what triggered the warning. Turns out this was a repeat maintenance item; and had been written up several times recently. For the subsequent takeoff; we selected flaps 15; as we didn't quite trust the minimum setting any longer. This gave us a cushion from any stray electrons at flaps 10; and in fact gave us an even greater stopping margin. Next takeoff was uneventful.
Original NASA ASRS Text
Title: MD11 flight crew experiences a takeoff warning for flaps although the flaps are correctly set at 10 degrees. The takeoff is rejected at 90 KTS and the flight returns to the gate for maintenance.
Narrative: On takeoff; we rejected after getting a 'Flaps; Flaps' warning around 85 KTS; speed got to around 90 KTS max. Rejected takeoff was uneventful and we notified Tower immediately. We had set flaps 10 for takeoff right after start; did our Before Takeoff Checklist; both saw and verified flaps 10 on our PFD's and both saw a green box before takeoff. Flaps were set for takeoff to the minimum setting as per recent guidance from the company; at flaps 10. While a good idea in theory; as it is much less drag should one lose an engine at or after V1; in my opinion this setting can and did possibly result in this rejected takeoff; through a flap transmitter sending an erroneous signal to the flight control computer and giving a false signal that the flaps were less than flaps 10; the minimum setting. On taxiing clear of the runway after the reject; we spoke with Maintenance over the Sat-Phone and it was agreed we should go back to the gate and have local mechanics check out the situation. Never did we see less than flaps 10 on our PFD's until selected so by us after clearing the runway; although right after the reject; I did see my PFD showing an intermittent and back-and-forth flaps 10 changing to flaps 11 annunciation; very rapidly and short in duration. If this signal was ever less than flaps 10 on takeoff; I suspect that this is what triggered the warning. Turns out this was a repeat maintenance item; and had been written up several times recently. For the subsequent takeoff; we selected flaps 15; as we didn't quite trust the minimum setting any longer. This gave us a cushion from any stray electrons at flaps 10; and in fact gave us an even greater stopping margin. Next takeoff was uneventful.
Data retrieved from NASA's ASRS site as of July 2013 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.