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Giv flight crew experiences airspeed deviation; track deviation and GPWS alert due to minor EFIS change out of vny.
| Attributes | |
| ACN | 659931 |
| Time | |
| Date | 200505 |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | airport : vny.airport |
| State Reference | CA |
| Altitude | msl single value : 1700 |
| Environment | |
| Flight Conditions | VMC |
| Light | Dusk |
| Aircraft 1 | |
| Controlling Facilities | tracon : sct.tracon |
| Operator | general aviation : corporate |
| Make Model Name | Gulfstream IV |
| Operating Under FAR Part | Part 91 |
| Flight Phase | climbout : initial |
| Route In Use | departure sid : glendale |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : corporate |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 85 flight time total : 15000 flight time type : 1600 |
| ASRS Report | 659931 |
| Person 2 | |
| Affiliation | company : corporate |
| Function | flight crew : first officer |
| Events | |
| Anomaly | aircraft equipment problem : less severe non adherence : clearance non adherence : published procedure other anomaly other spatial deviation other spatial deviation non adherence : published procedure |
| Independent Detector | aircraft equipment : gpws other controllera other flight crewa other flight crewb |
| Resolutory Action | flight crew : overcame equipment problem flight crew : regained aircraft control flight crew : overrode automation flight crew : returned to intended or assigned course |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance Aircraft |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
We were assigned the glendale 8 departure from vny with an unrestr climb to 4000 ft. The experienced sic was flying and decided to level at 1700 ft per the SID for noise abatement reasons. We normally take off with 1700 ft set in the altitude preselect to comply with the SID; but this time we set 4000 ft since we were cleared for unrestr climb. When the preselect is set to 1700 ft; the autothrottles reduce power immediately when we select the climb profile in order to level at 1700 ft and maintain 200 KTS or less. With 4000 ft set; the autothrottles went to full climb power and our airspeed quickly increased surprising the PF. By the time he sorted out what was happening; we had passed the vny 2.2 DME where a left turn was called for. After turning off the autothrottles and getting the airspeed back down; he began the turn to 110 degrees per the SID. There is rising terrain south of vny which tripped a GPWS alert. There was no safety issue because we were well aware of the terrain and could see it clearly. This was a case where a subtle change in our pre takeoff cockpit setup led to an airspeed excursion; track overshoot and GPWS alert within 20 seconds from liftoff. With automated airplanes you really have to think about the ramifications of small changes in the setup.
Original NASA ASRS Text
Title: GIV FLT CREW EXPERIENCES AIRSPD DEV; TRACK DEV AND GPWS ALERT DUE TO MINOR EFIS CHANGE OUT OF VNY.
Narrative: WE WERE ASSIGNED THE GLENDALE 8 DEP FROM VNY WITH AN UNRESTR CLB TO 4000 FT. THE EXPERIENCED SIC WAS FLYING AND DECIDED TO LEVEL AT 1700 FT PER THE SID FOR NOISE ABATEMENT REASONS. WE NORMALLY TAKE OFF WITH 1700 FT SET IN THE ALT PRESELECT TO COMPLY WITH THE SID; BUT THIS TIME WE SET 4000 FT SINCE WE WERE CLRED FOR UNRESTR CLB. WHEN THE PRESELECT IS SET TO 1700 FT; THE AUTOTHROTTLES REDUCE PWR IMMEDIATELY WHEN WE SELECT THE CLB PROFILE IN ORDER TO LEVEL AT 1700 FT AND MAINTAIN 200 KTS OR LESS. WITH 4000 FT SET; THE AUTOTHROTTLES WENT TO FULL CLB PWR AND OUR AIRSPD QUICKLY INCREASED SURPRISING THE PF. BY THE TIME HE SORTED OUT WHAT WAS HAPPENING; WE HAD PASSED THE VNY 2.2 DME WHERE A L TURN WAS CALLED FOR. AFTER TURNING OFF THE AUTOTHROTTLES AND GETTING THE AIRSPD BACK DOWN; HE BEGAN THE TURN TO 110 DEGS PER THE SID. THERE IS RISING TERRAIN S OF VNY WHICH TRIPPED A GPWS ALERT. THERE WAS NO SAFETY ISSUE BECAUSE WE WERE WELL AWARE OF THE TERRAIN AND COULD SEE IT CLRLY. THIS WAS A CASE WHERE A SUBTLE CHANGE IN OUR PRE TKOF COCKPIT SETUP LED TO AN AIRSPD EXCURSION; TRACK OVERSHOOT AND GPWS ALERT WITHIN 20 SECONDS FROM LIFTOFF. WITH AUTOMATED AIRPLANES YOU REALLY HAVE TO THINK ABOUT THE RAMIFICATIONS OF SMALL CHANGES IN THE SETUP.
Data retrieved from NASA's ASRS site as of January 2009 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.