GPWS

From Rise: The Vieneo Province

The GPWS (pronounced jip-wiz) is an ackronym for Ground Proximity Warning System and is a safety device factory standard in aircraft and aerospace vehicles to alert the flight crew when one of the following thresholds are exceeded.

Mode 1 - Excessive Decent Rate

Mode 1 Envelope

Has two (2) boundaries and is independent of vehicle configuration.

Penetration of the first boundary generates the repeated aural alert of "sink rate".

Penetrating the second boundary causes the repeated aural warning of "WOOP WOOP, pull up", until the rate of decent has been corrected.






Mode 2 - Excessive Terrain Closure Rate

Mode 2 Envelope

Monitors airspeed, AGL altitude and AGL rate-of-change, MSL altitude and vehicle configuration.

It has two (2) boundaries, the first causes an aural alert of "terrain, terrain", followed by the repeated aural warning of "WOOP WOOP, pull up". After leaving the "pull up" area the repeating "terrain" message will be herd while in that portion of the envelope. If both boundaries are penetrated while in the landing configuration, only the repeating "terrain" aural alert will occur. If the landing gear and wing flaps (where applicable) are not in the landing position when leaving the "pull up" area, 91.5 meters MSL altitude must be gained before the aural "terrain" alert is silenced. As the IAS increases with the gear up, the highest altitude at which a mode two alert warning will occur is increased to 746.5 meters. This higher portion is inhibited with the flap inhibit switch on.



Mode 3 - Altitude Loss After Takeoff Or Rejected Landing

Mode 3 Envelope
This mode is not yet employed in Rise.

Provides an alert if a decent is made during initial climb or climb after rejected landing. The aural alert is a voice message "don't sink", repeated until the condition is corrected. It is effective between 15 and 215 meters AGL and generates the alert when accumulated MSL loss equals approximately 10% of the existing AGL altitude. This mode does not arm during decent until below 60 meters AGL.





Mode 4 - Unsafe Terrain Clearance

Mode 4a Envelope

Mode 4a - Clean Configuration

This is the terrain clearance mode with the gear retracted, is armed after take off upon climbing through 215 meters AGL. When this envelope is penetrated at less than a given IAS the aural alert "struts" is sounded. When the envelope is penetrated at more than a given IAS the aural alert "too low, terrain" is sounded and the upper boundary of the envelope is increased to 305 meters AGL. The message is repeated until the flight condition has been corrected.





Mode 4b Envelope

Mode 4b - Landing Configuration

This mode provides an alert when the gear is down and the flaps are not in landing position. If the envelope is penetrated at less than a given IAS with the flaps not in the landing position, the aural alert "too low, flaps" is sounded. When the envelope is penetrated at more than a given IAS, the aural alert of "too low, terrain" is sounded and the upper boundary is increased to 305 meters AGL. The voice messages continue to occur until the flight condition has been corrected. The "struts" alert takes priority over "too low, flaps". The "too low, flaps" and associated "too low, terrain" alert are inhibited with the flap inhibit switch on.



Mode 5 - Below Glideslope Deviation Alert

Mode 5 Envelope
This mode is not yet employed in Rise.

This mode alerts you of a descent of more than 1.3 dots below an ILS glideslope. The envelope has two areas of alerting, soft and loud. In both areas is a repeated aural warning of "glideslope". The voice message amplitude is increased when entering the loud area In both areas, the aural warning repetition rate is increased as glideslope deviation increases and radio altitude decreases. The mode is armed when the autoflyte vertical mode "G/S" is captured. Mode 1 through 4 aural alerts and warnings have priority over mode 5 aural alerts.





Mode 6 - Excessive Bank Angle For Altitude