|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||0601 To 1200|
|Locale Reference||airport : zzz.airport|
|Altitude||agl single value : 0|
|Operator||common carrier : air carrier|
|Make Model Name||MD-88|
|Operating Under FAR Part||Part 121|
|Flight Phase||ground : takeoff roll|
ground : maintenance
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : atp|
|Experience||flight time last 90 days : 200|
flight time total : 10000
flight time type : 5000
|Affiliation||company : air carrier|
|Function||maintenance : technician|
|Anomaly||aircraft equipment problem : critical|
|Independent Detector||aircraft equipment other aircraft equipment : airspeed indicator|
|Resolutory Action||flight crew : rejected takeoff|
|Maintenance||performance deficiency : repair|
performance deficiency : testing
performance deficiency : fault isolation
|Problem Areas||Maintenance Human Performance|
|Primary Problem||Maintenance Human Performance|
Prior to takeoff; all instruments indicated properly. A few seconds after initiating the takeoff roll; the first officer called 'clamp' at 60 KTS. I glanced at my instruments and noticed my airspeed indicator was showing 0 KIAS with an 'off' flag and an 'airspeed' flag. I quickly checked the other instruments and saw no other abnormal indications. Prior to 80 KIAS; I elected to discontinue takeoff. I retarded the throttles to idle and used reverse thrust. Autobrakes and autospoilers worked normally. I turned off runway at taxiway D7. The aircraft slowed in a calm manner. The first officer alerted tower that we were discontinuing takeoff immediately upon my initiation of the procedure. We requested no assistance from crash fire rescue equipment. We returned to the gate; where maintenance repaired the jet. Passenger remained calm at all times. After replacement of the #1 air data computer; we were redispatched. Again; the instruments were normal prior to takeoff. At an estimated 40 KTS my airspeed indicator again displayed an 'off' flag and 'airspeed' flag. I discontinued the takeoff with no further incident. We returned to the gate for maintenance. After this attempt; the flight was canceled. Callback conversation with reporter revealed the following information: reporter stated after initially discontinuing the takeoff roll; maintenance decided to change the air data computer. However; the same air speed indicator again displayed an 'off' flag and an 'a/south' flag during the second takeoff roll. Flight was canceled. Reporter does not know what corrective action maintenance performed to fix the discrepancy.
Original NASA ASRS Text
Title: AN MD-88 CAPTAIN NOTED DURING THEIR SECOND ATTEMPT ON TKOF ROLL THAT HIS AIRSPEED INDICATOR WAS SHOWING '0' KIAS WITH AN 'OFF' FLAG AND AN 'A/S' FLAG. FLIGHT CANCELED.
Narrative: PRIOR TO TKOF; ALL INSTS INDICATED PROPERLY. A FEW SECONDS AFTER INITIATING THE TKOF ROLL; THE FO CALLED 'CLAMP' AT 60 KTS. I GLANCED AT MY INSTS AND NOTICED MY AIRSPD INDICATOR WAS SHOWING 0 KIAS WITH AN 'OFF' FLAG AND AN 'AIRSPD' FLAG. I QUICKLY CHKED THE OTHER INSTS AND SAW NO OTHER ABNORMAL INDICATIONS. PRIOR TO 80 KIAS; I ELECTED TO DISCONTINUE TKOF. I RETARDED THE THROTTLES TO IDLE AND USED REVERSE THRUST. AUTOBRAKES AND AUTOSPOILERS WORKED NORMALLY. I TURNED OFF RWY AT TXWY D7. THE ACFT SLOWED IN A CALM MANNER. THE FO ALERTED TWR THAT WE WERE DISCONTINUING TKOF IMMEDIATELY UPON MY INITIATION OF THE PROC. WE REQUESTED NO ASSISTANCE FROM CFR. WE RETURNED TO THE GATE; WHERE MAINT REPAIRED THE JET. PAX REMAINED CALM AT ALL TIMES. AFTER REPLACEMENT OF THE #1 ADC; WE WERE REDISPATCHED. AGAIN; THE INSTS WERE NORMAL PRIOR TO TKOF. AT AN ESTIMATED 40 KTS MY AIRSPD INDICATOR AGAIN DISPLAYED AN 'OFF' FLAG AND 'AIRSPD' FLAG. I DISCONTINUED THE TKOF WITH NO FURTHER INCIDENT. WE RETURNED TO THE GATE FOR MAINT. AFTER THIS ATTEMPT; THE FLT WAS CANCELED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED AFTER INITIALLY DISCONTINUING THE TAKEOFF ROLL; MAINT DECIDED TO CHANGE THE AIR DATA COMPUTER. HOWEVER; THE SAME AIR SPEED INDICATOR AGAIN DISPLAYED AN 'OFF' FLAG AND AN 'A/S' FLAG DURING THE SECOND TAKEOFF ROLL. FLIGHT WAS CANCELED. REPORTER DOES NOT KNOW WHAT CORRECTIVE ACTION MAINT PERFORMED TO FIX THE DISCREPANCY.
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.