Narrative:

During takeoff roll upon application of power for takeoff we did not get the automatic pack trip system. We aborted takeoff with less than 60 KIAS--I believe approximately 30 KTS. Upon clearing the runway and following our abnormal checklist procedures we discovered that the inboard flaps had moved from 15 degrees to approximately 10 degrees, although the flap handle had not been moved. Upon recycling the flaps, all returned to normal. However, when I jiggled the flap handle within the confines of the 15 degree detent the inbound flaps moved again to a position between 10 and 15 degrees. They were again recycled and positions verified visually. A normal takeoff was made. Upon arrival at our destination, bhm, demonstrated this phenomenon to the maintenance mechanic on duty in the presence of the other 2 pilots. The maintenance mechanic performed several checks of the system in compliance with his procedures, and to the satisfaction of the captain. I feel that what happened to us, that is an uncommanded partial retraction of the inboard flaps, has potentially catastrophic consequences. I have been told that it could not possible happen, but, west/O a doubt, it did! Callback conversation with reporter revealed the following: reporter has flown same aircraft several times since incident and has not been able to duplicate the split flap condition. His airline company has taken notice of the log book write-up and has issued an article in their safety bulletin for flight crews to be alert for the possibility of the incident recurring. The alpa safety committee followed up on the incident, but no record of it ever happening before this nor since.

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Original NASA ASRS Text

Title: FLT CREW ABORTED TKOF WHEN AUTO PACK GREEN LIGHT DID NOT ACTIVATE--NOTICED SPLIT OF 5 DEGREES BETWEEN INBOARD FLAPS AND OUTBOARD FLAPS. FLT MADE ANOTHER TKOF AND LANDED AT BHM WHERE GND MAINTENANCE WAS MADE AWARE OF INCIDENT AND WAS DEMONSTRATED TO THEM. MAINTENANCE ACTIVITY. INCIDENT HAS NOT RECURRED.

Narrative: DURING TKOF ROLL UPON APPLICATION OF PWR FOR TKOF WE DID NOT GET THE AUTO PACK TRIP SYS. WE ABORTED TKOF WITH LESS THAN 60 KIAS--I BELIEVE APPROX 30 KTS. UPON CLRING THE RWY AND FOLLOWING OUR ABNORMAL CHKLIST PROCS WE DISCOVERED THAT THE INBOARD FLAPS HAD MOVED FROM 15 DEGS TO APPROX 10 DEGS, ALTHOUGH THE FLAP HANDLE HAD NOT BEEN MOVED. UPON RECYCLING THE FLAPS, ALL RETURNED TO NORMAL. HOWEVER, WHEN I JIGGLED THE FLAP HANDLE WITHIN THE CONFINES OF THE 15 DEG DETENT THE INBND FLAPS MOVED AGAIN TO A POS BTWN 10 AND 15 DEGS. THEY WERE AGAIN RECYCLED AND POSITIONS VERIFIED VISUALLY. A NORMAL TKOF WAS MADE. UPON ARR AT OUR DEST, BHM, DEMONSTRATED THIS PHENOMENON TO THE MAINT MECH ON DUTY IN THE PRESENCE OF THE OTHER 2 PLTS. THE MAINT MECH PERFORMED SEVERAL CHKS OF THE SYS IN COMPLIANCE WITH HIS PROCS, AND TO THE SATISFACTION OF THE CAPT. I FEEL THAT WHAT HAPPENED TO US, THAT IS AN UNCOMMANDED PARTIAL RETRACTION OF THE INBOARD FLAPS, HAS POTENTIALLY CATASTROPHIC CONSEQUENCES. I HAVE BEEN TOLD THAT IT COULD NOT POSSIBLE HAPPEN, BUT, W/O A DOUBT, IT DID! CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR HAS FLOWN SAME ACFT SEVERAL TIMES SINCE INCIDENT AND HAS NOT BEEN ABLE TO DUPLICATE THE SPLIT FLAP CONDITION. HIS AIRLINE COMPANY HAS TAKEN NOTICE OF THE LOG BOOK WRITE-UP AND HAS ISSUED AN ARTICLE IN THEIR SAFETY BULLETIN FOR FLT CREWS TO BE ALERT FOR THE POSSIBILITY OF THE INCIDENT RECURRING. THE ALPA SAFETY COMMITTEE FOLLOWED UP ON THE INCIDENT, BUT NO RECORD OF IT EVER HAPPENING BEFORE THIS NOR SINCE.

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.