A medium turbojet on takeoff roll rejected the takeoff at less than 50 KTS due takeoff warning horn ...

Attributes
ACN	487534
Time
Date	200009
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : lax.airport
State Reference	CA
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : lax.tower
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	ground : takeoff roll
Route In Use	departure : other published ifr departure
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : cfi pilot : multi engine
Experience	flight time last 90 days : 210 flight time total : 7000 flight time type : 1000
ASRS Report	487534
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : take off warning system other flight crewa other flight crewb
Resolutory Action	flight crew : rejected takeoff
Consequence	other other
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Aircraft

Narrative:

Scheduled flight day, lax-psp. Just prior to departure time, at the gate, maintenance discovered a possible hydraulic leak that they wanted to troubleshoot. At maintenance's direction we pressurized a and B hydraulics and lowered the flaps to 5 degrees. With the flaps in this position we noticed the leading edge flaps transit annunciator on the forward panel remained illuminated. The overhead panel showed the #2 leading edge slat in-transit. The flaps were cycled to 1 degree. Both of the in-transit indications remained the same. The flaps were cycled to 10 degrees and the flaps/slats indicated full extend. The flaps were retracted to 5 degrees, and the full extend indications remained. The flaps were fully retracted, and then extended to flap position 1 degree. All indications were normal. It should be noted that maintenance directed our actions during the troubleshooting of the flaps. Maintenance determined that the errant flap indication was an isolated incident, and sent us on our way. As we taxied out for takeoff, or call the flaps were positioned to 1 degree, all cockpit indications were normal. All leading edge devices were indicating proper position. It was my takeoff. As I applied takeoff thrust, the takeoff warning horn sounded. I brought the thrust levers to idle and the takeoff was aborted at a low speed (below 50 KTS).

Original NASA ASRS Text

Title: A MEDIUM TURBOJET ON TKOF ROLL REJECTED THE TKOF AT LESS THAN 50 KTS DUE TKOF WARNING HORN SOUNDING.

Narrative: SCHEDULED FLT DAY, LAX-PSP. JUST PRIOR TO DEP TIME, AT THE GATE, MAINT DISCOVERED A POSSIBLE HYD LEAK THAT THEY WANTED TO TROUBLESHOOT. AT MAINT'S DIRECTION WE PRESSURIZED A AND B HYDS AND LOWERED THE FLAPS TO 5 DEGS. WITH THE FLAPS IN THIS POS WE NOTICED THE LEADING EDGE FLAPS TRANSIT ANNUNCIATOR ON THE FORWARD PANEL REMAINED ILLUMINATED. THE OVERHEAD PANEL SHOWED THE #2 LEADING EDGE SLAT IN-TRANSIT. THE FLAPS WERE CYCLED TO 1 DEG. BOTH OF THE IN-TRANSIT INDICATIONS REMAINED THE SAME. THE FLAPS WERE CYCLED TO 10 DEGS AND THE FLAPS/SLATS INDICATED FULL EXTEND. THE FLAPS WERE RETRACTED TO 5 DEGS, AND THE FULL EXTEND INDICATIONS REMAINED. THE FLAPS WERE FULLY RETRACTED, AND THEN EXTENDED TO FLAP POS 1 DEG. ALL INDICATIONS WERE NORMAL. IT SHOULD BE NOTED THAT MAINT DIRECTED OUR ACTIONS DURING THE TROUBLESHOOTING OF THE FLAPS. MAINT DETERMINED THAT THE ERRANT FLAP INDICATION WAS AN ISOLATED INCIDENT, AND SENT US ON OUR WAY. AS WE TAXIED OUT FOR TKOF, OR CALL THE FLAPS WERE POSITIONED TO 1 DEG, ALL COCKPIT INDICATIONS WERE NORMAL. ALL LEADING EDGE DEVICES WERE INDICATING PROPER POS. IT WAS MY TKOF. AS I APPLIED TKOF THRUST, THE TKOF WARNING HORN SOUNDED. I BROUGHT THE THRUST LEVERS TO IDLE AND THE TKOF WAS ABORTED AT A LOW SPD (BELOW 50 KTS).

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.

A medium turbojet on takeoff roll rejected the takeoff at less than 50 KTS due takeoff warning horn sounding.