Situations Where No‐Gyro or ASR Approach are Warranted

Lesson 4

Table 1 gives four different situations for when radar approach or no-gyro vectors may be warranted. Scenarios where these situations might occur are:

‘Normal’ vectors to intercept a published approach, with the aircraft flight display working properly.
- This is the typical, normal condition
No‐gyro vectors to intercept a published approach, “without flight indications”. Navigation equipment and its display are still functioning. Possible scenarios:
- Attitude, Heading & Reference System (AHRS), or vacuum pump has failed
- Backup display is mounted in a location that is difficult to view
- Backup display fails
- Only the Magnetic compass for heading information and high workload
‘Normal’ vectors to, and execution of, an ASR approach when published electronic approach is not available and aircraft flight display is working. Possible scenario:
- Ground equipment or GPS for published electronic approach is not available;
- Failure of aircraft navigation equipment but flight display is working properly.
- Don’t have appropriate approach charts on board
No‐gyro vectors to, and execution of, a no‐gyro approach when published electronic approach is not available and aircraft flight display is “without flight indications”. Possible scenarios:
- PFD and MFD have failed.
- Complete electrical failure

Table 1. Summary of the Different Situations for No-Gyro and ASR Approaches.

Aircraft Systems	Type of Approach	Where
All aircraft systems normal	Published approach	Any ASR facility
"without primary flight indications" Course guidance still available	Published approach	Any ASR facility
No course guidance available Flight Indications normal	ASR Radar approach	Only airport with published ASR approach
No course guidance available and "without primary flight indications"	ASR Radar approach	Only airport with published ASR approach