|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Locale Reference||airport : zzz.airport|
|Altitude||msl single value : 8000|
|Controlling Facilities||tracon : zzz.tracon|
|Operator||common carrier : air carrier|
|Make Model Name||B737-300|
|Operating Under FAR Part||Part 121|
|Flight Phase||climbout : takeoff|
|Route In Use||departure sid : n/s|
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Experience||flight time last 90 days : 200|
flight time total : 13750
flight time type : 6000
|Anomaly||aircraft equipment problem : less severe|
|Independent Detector||other flight crewa|
|Resolutory Action||flight crew : declared emergency|
After takeoff runway xxl; could not select VNAV after flap retraction. Could not select climb mode reduced thrust. Used level change; first officer flying. Noticed TCAS fail and ATC asked us to switch xponders. They got contact briefly when I selected left transponder. Talking to departure; climbing to 13000 ft; got check position message. ACARS flashed delay code and I saw that we were not indicating off time on ACARS. I told first officer that I thought the air/sensor switch had failed in ground mode. We contacted dispatch and maintenance control. First officer told ATC after clearing us to FL230 that we'd like to maintain FL200 and were working with maintenance on a problem. They were having trouble with our transponder and we switched out of TA/RA to transponder only. ATC vectored us. Maintenance control had me pull the air/ground sensor breaker to put us in flight mode. We would not have reverse on landing and would reset breaker after touchdown. Dispatch; maintenance control and I decided to return to ZZZ1. I declared emergency to ensure long full length runway at ZZZ. We returned and landed on runway xy; manual speed brakes and no reverse; full length. Equipment was standing by and landing was uneventful. We taxied to gate; briefed maintenance and plane was taken OTS. 1 flight attendant did not feel emotionally able to continue on next flight. Passenger went to next gate and we flew in other aircraft to ZZZ2.
Original NASA ASRS Text
Title: A B737-300 FLT CREW EXPERIENCED FAILURE OF THE AIR/GROUND SWITCH AFTER TAKEOFF; AFFECTING A NUMBER OF SYSTEMS. THEY DECLARED AN EMERGENCY AND RETURNED TO DEPARTURE AIRPORT.
Narrative: AFTER TKOF RWY XXL; COULD NOT SELECT VNAV AFTER FLAP RETRACTION. COULD NOT SELECT CLB MODE REDUCED THRUST. USED LEVEL CHANGE; FO FLYING. NOTICED TCAS FAIL AND ATC ASKED US TO SWITCH XPONDERS. THEY GOT CONTACT BRIEFLY WHEN I SELECTED L XPONDER. TALKING TO DEP; CLBING TO 13000 FT; GOT CHK POS MESSAGE. ACARS FLASHED DELAY CODE AND I SAW THAT WE WERE NOT INDICATING OFF TIME ON ACARS. I TOLD FO THAT I THOUGHT THE AIR/SENSOR SWITCH HAD FAILED IN GND MODE. WE CONTACTED DISPATCH AND MAINT CTL. FO TOLD ATC AFTER CLRING US TO FL230 THAT WE'D LIKE TO MAINTAIN FL200 AND WERE WORKING WITH MAINT ON A PROB. THEY WERE HAVING TROUBLE WITH OUR XPONDER AND WE SWITCHED OUT OF TA/RA TO XPONDER ONLY. ATC VECTORED US. MAINT CTL HAD ME PULL THE AIR/GND SENSOR BREAKER TO PUT US IN FLT MODE. WE WOULD NOT HAVE REVERSE ON LNDG AND WOULD RESET BREAKER AFTER TOUCHDOWN. DISPATCH; MAINT CTL AND I DECIDED TO RETURN TO ZZZ1. I DECLARED EMER TO ENSURE LONG FULL LENGTH RWY AT ZZZ. WE RETURNED AND LANDED ON RWY XY; MANUAL SPD BRAKES AND NO REVERSE; FULL LENGTH. EQUIP WAS STANDING BY AND LNDG WAS UNEVENTFUL. WE TAXIED TO GATE; BRIEFED MAINT AND PLANE WAS TAKEN OTS. 1 FLT ATTENDANT DID NOT FEEL EMOTIONALLY ABLE TO CONTINUE ON NEXT FLT. PAX WENT TO NEXT GATE AND WE FLEW IN OTHER ACFT TO ZZZ2.
Data retrieved from NASA's ASRS site as of May 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.