|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Locale Reference||airport : msy|
|Altitude||agl bound lower : 0|
agl bound upper : 3000
|Controlling Facilities||tracon : msy|
|Operator||common carrier : air carrier|
|Make Model Name||Medium Large Transport, Low Wing, 2 Turbojet Eng|
|Navigation In Use||Other|
|Flight Phase||climbout : takeoff|
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : instrument|
pilot : commercial
pilot : atp
|Experience||flight time last 90 days : 200|
flight time total : 8000
flight time type : 2000
|Affiliation||company : air carrier|
|Function||flight crew : first officer|
|Qualification||pilot : commercial|
pilot : instrument
|Anomaly||aircraft equipment problem : less severe|
|Independent Detector||other flight crewa|
|Resolutory Action||none taken : anomaly accepted|
|Air Traffic Incident||other|
Takeoff acceleration correspondingly rapid. Runway 28 used. Takeoff roll normal and all 3 airspeed indicators checked at 100 KIAS. At V1 on captain's side (captain's takeoff) the first officer's indicator read approximately 10 KTS low. Standby airspeed indicator checked and ground speed indicator checked. Due to rapid acceleration, takeoff continued using all captain's information. By this time it was obvious the first officer's airspeed indicator was unreliable (fluctuating airspeed, slow build up, intermittent flags, etc). At approximately 1000' first officer's static selector switched to alternate. No change and returned to normal. No changes. VHF/navigation switches all selected to both left, no change, then returned to normal, no change. At 3000' I queried ATC and their ground speed readout agreed with the information on my (captain's) side. I rechked en route and terminal WX reports and they indicated that the en route and terminal WX presented no obstacle to successful flight. The captain's standby static source-checked ok. Circuit breaker tests indicated that the #2 CADC appeared to be the culprit. I decided to continue the flight. Periodic checks with ATC confirmed that the captain's airspeed indicators were functioning properly. The flight to jan was routine and uneventful.
Original NASA ASRS Text
Title: DISCOVERED FO'S AIRSPEED UNRELIABLE AT V1. FLT CONTINUED TO DESTINATION.
Narrative: TKOF ACCELERATION CORRESPONDINGLY RAPID. RWY 28 USED. TKOF ROLL NORMAL AND ALL 3 AIRSPD INDICATORS CHKED AT 100 KIAS. AT V1 ON CAPT'S SIDE (CAPT'S TKOF) THE F/O'S INDICATOR READ APPROX 10 KTS LOW. STANDBY AIRSPD INDICATOR CHKED AND GND SPD INDICATOR CHKED. DUE TO RAPID ACCELERATION, TKOF CONTINUED USING ALL CAPT'S INFO. BY THIS TIME IT WAS OBVIOUS THE F/O'S AIRSPD INDICATOR WAS UNRELIABLE (FLUCTUATING AIRSPD, SLOW BUILD UP, INTERMITTENT FLAGS, ETC). AT APPROX 1000' F/O'S STATIC SELECTOR SWITCHED TO ALTERNATE. NO CHANGE AND RETURNED TO NORMAL. NO CHANGES. VHF/NAV SWITCHES ALL SELECTED TO BOTH LEFT, NO CHANGE, THEN RETURNED TO NORMAL, NO CHANGE. AT 3000' I QUERIED ATC AND THEIR GND SPD READOUT AGREED WITH THE INFO ON MY (CAPT'S) SIDE. I RECHKED ENRTE AND TERMINAL WX RPTS AND THEY INDICATED THAT THE ENRTE AND TERMINAL WX PRESENTED NO OBSTACLE TO SUCCESSFUL FLT. THE CAPT'S STANDBY STATIC SOURCE-CHKED OK. CB TESTS INDICATED THAT THE #2 CADC APPEARED TO BE THE CULPRIT. I DECIDED TO CONTINUE THE FLT. PERIODIC CHKS WITH ATC CONFIRMED THAT THE CAPT'S AIRSPD INDICATORS WERE FUNCTIONING PROPERLY. THE FLT TO JAN WAS ROUTINE AND UNEVENTFUL.
Data retrieved from NASA's ASRS site as of August 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.