 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
C172 pilot reports difficulty maintaining altitude and heading on an IFR flight plan in IMC; and discovers that the vacuum pump is working intermittently. The standby pump is engaged but during the troubleshooting process the avionics power switch is inadvertently turned off requiring a restart and programing of the GPS.
| Attributes | |
| ACN | 1104748 |
| Time | |
| Date | 201307 |
| Local Time Of Day | 1801-2400 |
| Place | |
| Locale Reference | ZZZ.TRACON |
| State Reference | US |
| Environment | |
| Flight Conditions | IMC |
| Light | Daylight |
| Aircraft 1 | |
| Make Model Name | Skyhawk 172/Cutlass 172 |
| Operating Under FAR Part | Part 91 |
| Flight Phase | Cruise |
| Route In Use | Direct |
| Flight Plan | IFR |
| Component | |
| Aircraft Component | Vacuum Pump |
| Person 1 | |
| Function | Pilot Flying Single Pilot |
| Qualification | Flight Crew Instrument Flight Crew Private |
| Experience | Flight Crew Last 90 Days 30 Flight Crew Total 650 Flight Crew Type 650 |
| Events | |
| Anomaly | Aircraft Equipment Problem Critical Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance Deviation - Track / Heading All Types |
Narrative:
During IFR flight talking to approach control; I began to experience heading/altitude control issues. By correcting for perceived incorrect heading; I lost approximately 300 ft of altitude near [an] air force base where active flight operations were underway. My assigned altitude was 3;000 ft MSL. I eventually determined that my vacuum pump was working intermittently and causing false readings on the directional gyro (dg) and attitude indicator; and I engaged the standby vacuum system. Also at this point; I inadvertently turned off the avionics power switch and had to restart the GPS for the route and approach. Once the GPS was reprogrammed and the standby vacuum was engaged; the remainder of the flight went as planned.
Original NASA ASRS Text
Title: C172 pilot reports difficulty maintaining altitude and heading on an IFR flight plan in IMC; and discovers that the vacuum pump is working intermittently. The standby pump is engaged but during the troubleshooting process the avionics power switch is inadvertently turned off requiring a restart and programing of the GPS.
Narrative: During IFR flight talking to Approach Control; I began to experience heading/altitude control issues. By correcting for perceived incorrect heading; I lost approximately 300 FT of altitude near [an] Air Force Base where active flight operations were underway. My assigned altitude was 3;000 FT MSL. I eventually determined that my vacuum pump was working intermittently and causing false readings on the directional gyro (DG) and attitude indicator; and I engaged the standby vacuum system. Also at this point; I inadvertently turned off the avionics power switch and had to restart the GPS for the route and approach. Once the GPS was reprogrammed and the standby vacuum was engaged; the remainder of the flight went as planned.
Data retrieved from NASA's ASRS site as of July 2013 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.