Aircraft equipment problem captain's seat slid to the rear on takeoff roll.

Attributes
ACN	302893
Time
Date	199504
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : arn
State Reference	FO
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-500
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 60 flight time total : 10000 flight time type : 6000
ASRS Report	302893
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : rejected takeoff
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

5 min taxi after pushback. Rudder pedals were checked for full travel. Parking brake set after pushback and released. During takeoff acceleration, around 80 KIAS, my seat suddenly and violently slid back and to the side, away from the pedestal. My feet barely touched rudder/brake pedals. I ordered 'abort takeoff' after having transmitted flight controls to the first officer by calling 'you have controls' (company policy callouts). In our company, however, only capts are trained and supposed to perform reject takeoff actions. First officer eventually stopped the aircraft with light pedal pressure. I had already taken the spoilers out and thrust levers back. We used in all only 1600 ft of the 3300 ft runway and it was almost a non event. However, it is not the first time that seats slid away in B-737/300, 400, 500. I know of one case during rotation! There is definitely a design problem with these seats. They do not always lock and when they slide, they go all the way back and to the side. For me, there is a design flow.

Original NASA ASRS Text

Title: ACFT EQUIP PROB CAPT'S SEAT SLID TO THE REAR ON TKOF ROLL.

Narrative: 5 MIN TAXI AFTER PUSHBACK. RUDDER PEDALS WERE CHKED FOR FULL TRAVEL. PARKING BRAKE SET AFTER PUSHBACK AND RELEASED. DURING TKOF ACCELERATION, AROUND 80 KIAS, MY SEAT SUDDENLY AND VIOLENTLY SLID BACK AND TO THE SIDE, AWAY FROM THE PEDESTAL. MY FEET BARELY TOUCHED RUDDER/BRAKE PEDALS. I ORDERED 'ABORT TKOF' AFTER HAVING XMITTED FLT CTLS TO THE FO BY CALLING 'YOU HAVE CTLS' (COMPANY POLICY CALLOUTS). IN OUR COMPANY, HOWEVER, ONLY CAPTS ARE TRAINED AND SUPPOSED TO PERFORM REJECT TKOF ACTIONS. FO EVENTUALLY STOPPED THE ACFT WITH LIGHT PEDAL PRESSURE. I HAD ALREADY TAKEN THE SPOILERS OUT AND THRUST LEVERS BACK. WE USED IN ALL ONLY 1600 FT OF THE 3300 FT RWY AND IT WAS ALMOST A NON EVENT. HOWEVER, IT IS NOT THE FIRST TIME THAT SEATS SLID AWAY IN B-737/300, 400, 500. I KNOW OF ONE CASE DURING ROTATION! THERE IS DEFINITELY A DESIGN PROB WITH THESE SEATS. THEY DO NOT ALWAYS LOCK AND WHEN THEY SLIDE, THEY GO ALL THE WAY BACK AND TO THE SIDE. FOR ME, THERE IS A DESIGN FLOW.

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.