 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
B737 captain reported two possibly related instances in two different aircraft involving loss of altimeters; airspeed; and VNAV.
| Attributes | |
| ACN | 1584320 |
| Time | |
| Date | 201809 |
| Environment | |
| Flight Conditions | IMC |
| Light | Night |
| Aircraft 1 | |
| Make Model Name | B737 Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Cruise |
| Flight Plan | IFR |
| Component | |
| Aircraft Component | Air Data Computer |
| Person 1 | |
| Function | Pilot Not Flying Captain |
| Qualification | Flight Crew Air Transport Pilot (ATP) |
| Experience | Flight Crew Total 20000 Flight Crew Type 8815 |
| Events | |
| Anomaly | Aircraft Equipment Problem Critical |
Narrative:
Refer to prior [safety] reports. The conclusions of both [reports] were not reviewed as possibly being related. Both [incidents] were identical except for the airspeed too low and overspeed warnings which were experienced as well as all other items mentioned. All three airspeed and altimeters were inoperative in both cases. The [incidents] occurred in two different airplanes. The most recent occurred in night/IMC conditions with heavy thunderstorms at cruise; descent and approach. Ground based ATC radar was used to readout our altitude and groundspeed. We were unable to fly the GPS approach in use due to loss of VNAV. We used the opposing runway with raw data ILS on standby system with 20-30 knot tailwinds on a wet runway. The onboard [checklist] is in total error regarding the pitch and power settings. The QRH (quick reference handbook) references were accurate using the standby attitude indicator. Also the captain's ipad froze and the onboard paper QRH was used. First officer was manually flying the aircraft.
Original NASA ASRS Text
Title: B737 Captain reported two possibly related instances in two different aircraft involving loss of altimeters; airspeed; and VNAV.
Narrative: Refer to prior [safety] reports. The conclusions of both [reports] were not reviewed as POSSIBLY being related. Both [incidents] were identical except for the airspeed too low and overspeed warnings which were experienced as well as all other items mentioned. All three AIRSPEED and ALTIMETERS were INOPERATIVE in both cases. The [incidents] occurred in two different airplanes. The most recent occurred in night/IMC conditions with heavy thunderstorms at cruise; descent and approach. Ground based ATC radar was used to readout our altitude and groundspeed. We were unable to fly the GPS approach in use due to loss of VNAV. We used the opposing runway with raw data ILS on standby system with 20-30 knot tailwinds on a wet runway. The onboard [checklist] is in total error regarding the pitch and power settings. The QRH (Quick Reference Handbook) references were accurate using the standby attitude indicator. Also the Captain's iPad froze and the onboard paper QRH was used. First Officer was manually flying the aircraft.
Data retrieved from NASA's ASRS site 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.