A small transport jet on a ferry flight to vny; received a GPWS mode 2A terrain; pull up alert east ...

Attributes
ACN	875486
Time
Date	201002
Local Time Of Day	1201-1800
Place
Locale Reference	SCT.TRACON
State Reference	CA
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Make Model Name	Light Transport Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 91
Flight Phase	Initial Approach
Route In Use	Vectors
Flight Plan	IFR
Component
Aircraft Component	GPWS
Person 1
Function	Pilot Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Not Flying First Officer
Events
Anomaly	ATC Issue All Types Aircraft Equipment Problem Less Severe Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance

Narrative:

On ATC vector; expecting vny ILS 16R; heading 340 level at 5000; approximately 5 east of kadie intersection; 200 kts IAS. Autopilot engaged; left seat pilot flying and right seat pilot not flying with GPWS terrain map displayed due to high terrain to the north. Aircraft in IMC. Received GPWS 'terrain; terrain; pull up' warning. Radar altimeter had been indicating around 1500 and rapidly decreasing prior to warning. Initiated recovery and notified ATC immediately. Leveled at 5700 when warning ceased. ATC unperturbed due to no traffic in vicinity; just requested our full callsign and stated 5000 was a minimum vectoring altitude at our position. Our postflight analysis of charts indicated that the high rate of closure with terrain while being vectored on this heading could have led to the GPWS warning and that our system was operating as intended. GPWS mode 2A could provide warning requiring a recovery despite being at safe MVA due to algorithm of the rate of terrain closure and the very steep topography in the area. Coordination with ATC in this sector to provide slightly increased terrain separation could prevent a future GPWS recovery that may result in traffic conflict.

Original NASA ASRS Text

Title: A Small Transport Jet on a ferry flight to VNY; received a GPWS Mode 2A TERRAIN; PULL UP alert east of KADIE Intersection westbound on vectors to VNY Runway 16. The aircraft was level at 5;000' but the terrain rose rapidly.

Narrative: On ATC vector; expecting VNY ILS 16R; heading 340 level at 5000; approximately 5 east of KADIE intersection; 200 kTS IAS. Autopilot engaged; left seat Pilot Flying and right seat Pilot Not Flying with GPWS terrain map displayed due to high terrain to the north. Aircraft in IMC. Received GPWS 'TERRAIN; TERRAIN; PULL UP' warning. Radar altimeter had been indicating around 1500 and rapidly decreasing prior to warning. Initiated recovery and notified ATC immediately. Leveled at 5700 when warning ceased. ATC unperturbed due to no traffic in vicinity; just requested our full callsign and stated 5000 was a minimum vectoring altitude at our position. Our postflight analysis of charts indicated that the high rate of closure with terrain while being vectored on this heading could have led to the GPWS warning and that our system was operating as intended. GPWS mode 2A could provide warning requiring a recovery despite being at safe MVA due to algorithm of the rate of terrain closure and the very steep topography in the area. Coordination with ATC in this sector to provide slightly increased terrain separation could prevent a future GPWS recovery that may result in traffic conflict.

Data retrieved from NASA's ASRS site as of April 2012 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.

A small transport jet on a ferry flight to vny; received a GPWS mode 2A terrain; pull up alert east of kadie intersection westbound on vectors to vny runway 16. The aircraft was level at 5;000' but the terrain rose rapidly.