GPWS Flashcards
When are the Basic GPWS modes activated?
Active when the aircraft is below 2,500 ft.
What are the GPWS Basic Category modes?
- Mode 1: Excessive Descent Rate
- Mode 2: Excessive Terrain Closure Rate
- Mode 3: Altitude Loss After Takeoff or Go-around
- Mode 4: Unsafe Terrain Clearance
- Mode 5: Excessive Descent Below Glideslope
Only Basic GPWS alerts are dependent upon the aircraft’s gear and flap configuration.
What is the GPWS predictive category?
GPWS Predictive Category: Uses a worldwide terrain database and applies a GPS-derived geographic position of the aircraft.
Which warnings are inhibited if the TERR pb is selected to OFF?
If the TERR pb is selected to OFF, only the Predictive category warnings are inhibited.
What is the concern with GPWS if the navigation accuracy is low?
To prevent false terrain warnings, the Predictive modes of GPWS operation should be selected off if the navigation accuracy is low.
Which GPWS aural alerts must the flight crew initiate a go-around from?
The pilot must immediately initiate a go-around if TOO LOW GEAR or FLAPS is heard.
What indication will the flight crew have during a GPWS alert if the loudspeakers are set to off?
GPWS alerts will play on the loudspeakers independent of the LOUD SPEAKERS volume knob.
What is TCF?
Terrain Clearance Floor (TCF) uses a database of minimum altitudes for each runway where terrain data is available. Maintaining a 3 degree flight path will not allow penetration of the TCF.
What is RFCF?
Runway Field Clearance Floor (RFCF) is based on the aircraft’s current position and the height above the destination runway using geometric altitude in lieu of radio altitude. This provides improved protection at locations where the runway is significantly higher than the surrounding terrain.
When does the predictive GPWS function generate a caution?
If the predictive GPWS function determines that the aircraft is within approximately 60 seconds of hazardous terrain, a caution is generated and the terrain automatically displays on each ND.
If the predictive GPWS function determines that the aircraft is within approximately 60 seconds of an obstacle, a caution is generated (OBSTACLE, AHEAD) and the terrain automatically displays on each ND.
When does the predictive GPWS function generate a warning?
If the aircraft is within 30 seconds of hazardous terrain, a warning is generated and the terrain automatically displays on each ND.
Within 30 seconds of an obstacle, a warning is generated. (OBSTACLE AHEAD, PULL UP)
When would the flight crew use the G/S MODE pb on the GPWS panel?
When the flight crew is operating on an ILS approach with the GS inoperative.
