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A B737-300 in cruise at FL270 the flap handle was inadvertently moved to extend position. Noted aircraft rumble and transit lights. Handle moved to full retract detent.
| Attributes | |
| ACN | 695164 |
| Time | |
| Date | 200604 |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | airport : zzz.airport |
| State Reference | US |
| Altitude | msl single value : 27000 |
| Environment | |
| Flight Conditions | VMC |
| Weather Elements | Turbulence |
| Light | Night |
| Aircraft 1 | |
| Controlling Facilities | artcc : zzz.artcc tower : phx.tower |
| Operator | common carrier : air carrier |
| Make Model Name | B737-300 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Experience | flight time last 90 days : 222 flight time total : 25000 flight time type : 20000 |
| ASRS Report | 695164 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Experience | flight time last 90 days : 220 flight time total : 6000 flight time type : 3000 |
| ASRS Report | 695183 |
| Events | |
| Anomaly | aircraft equipment problem : critical altitude deviation : excursion from assigned altitude |
| Independent Detector | aircraft equipment other aircraft equipment : flap indication other flight crewa other flight crewb |
| Resolutory Action | flight crew : returned to assigned altitude flight crew : overcame equipment problem |
| Consequence | other other |
| Supplementary | |
| Problem Areas | Aircraft Flight Crew Human Performance |
| Primary Problem | Aircraft |
Narrative:
Leg #6; aircraft change in ZZZ1 third different aircraft. Departed ZZZ1 light to moderate turbulence in climb and during cruise. FL270 80 mi north of ZZZ. Center has given us direct to ZZZ2. I reached over to the FMC to program direct to ZZZ2. After I finished pushing the button; my forearm pulled back across the top of the flap handle. A second or 2 later; I noticed the amber flap transit light illuminated and felt a rumble and noticed the flap needles moving. I pushed the flap lever back forward toward the stop. The flap needle went back to zero and the flap transit light went out. Momentary altitude deviation of +100 feet and -50 ft. The whole extension/retraction lasted maybe 5 seconds. The first officer then checked the flap lever again and found it still not down in the detent; so he made sure it was in the detent. Rest of the flight was uneventful; flap extension was normal. Aircraft flight normal. On taxi in; we experimented with the flap lever. It took more force than normal to push the lever forward to the stop and then you had to physically force the handle down into the detent. The force required for this aircraft was much different than the other 2 -700 aircraft we had flown that day; and being night; in turbulence from takeoff; #6 leg; and a long day at that; we didn't notice the difference. Even though the flap gauge indicated zero; the flap lever was not in the detent; so just looking at the flap gauge is not foolproof either. Better check the lever; then the gauge.
Original NASA ASRS Text
Title: A B737-300 IN CRUISE AT FL270 THE FLAP HANDLE WAS INADVERTENTLY MOVED TO EXTEND POS. NOTED ACFT RUMBLE AND TRANSIT LIGHTS. HANDLE MOVED TO FULL RETRACT DETENT.
Narrative: LEG #6; ACFT CHANGE IN ZZZ1 THIRD DIFFERENT ACFT. DEPARTED ZZZ1 LIGHT TO MODERATE TURB IN CLB AND DURING CRUISE. FL270 80 MI N OF ZZZ. CTR HAS GIVEN US DIRECT TO ZZZ2. I REACHED OVER TO THE FMC TO PROGRAM DIRECT TO ZZZ2. AFTER I FINISHED PUSHING THE BUTTON; MY FOREARM PULLED BACK ACROSS THE TOP OF THE FLAP HANDLE. A SECOND OR 2 LATER; I NOTICED THE AMBER FLAP TRANSIT LIGHT ILLUMINATED AND FELT A RUMBLE AND NOTICED THE FLAP NEEDLES MOVING. I PUSHED THE FLAP LEVER BACK FORWARD TOWARD THE STOP. THE FLAP NEEDLE WENT BACK TO ZERO AND THE FLAP TRANSIT LIGHT WENT OUT. MOMENTARY ALTDEV OF +100 FEET AND -50 FT. THE WHOLE EXTENSION/RETRACTION LASTED MAYBE 5 SECONDS. THE FO THEN CHKED THE FLAP LEVER AGAIN AND FOUND IT STILL NOT DOWN IN THE DETENT; SO HE MADE SURE IT WAS IN THE DETENT. REST OF THE FLT WAS UNEVENTFUL; FLAP EXTENSION WAS NORMAL. ACFT FLT NORMAL. ON TAXI IN; WE EXPERIMENTED WITH THE FLAP LEVER. IT TOOK MORE FORCE THAN NORMAL TO PUSH THE LEVER FORWARD TO THE STOP AND THEN YOU HAD TO PHYSICALLY FORCE THE HANDLE DOWN INTO THE DETENT. THE FORCE REQUIRED FOR THIS ACFT WAS MUCH DIFFERENT THAN THE OTHER 2 -700 ACFT WE HAD FLOWN THAT DAY; AND BEING NIGHT; IN TURB FROM TKOF; #6 LEG; AND A LONG DAY AT THAT; WE DIDN'T NOTICE THE DIFFERENCE. EVEN THOUGH THE FLAP GAUGE INDICATED ZERO; THE FLAP LEVER WAS NOT IN THE DETENT; SO JUST LOOKING AT THE FLAP GAUGE IS NOT FOOLPROOF EITHER. BETTER CHK THE LEVER; THEN THE GAUGE.
Data retrieved from NASA's ASRS site as of January 2009 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.