G159 experienced near midair collision with C172 departure from parallel runway at vny.

Attributes
ACN	598651
Time
Date	200304
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : vny.vor
State Reference	CA
Altitude	msl single value : 1500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : vny.tower
Operator	common carrier : air taxi
Make Model Name	Gulfstream I (Large Turboprop)
Operating Under FAR Part	Part 135
Navigation In Use	other
Flight Phase	climbout : initial climbout : takeoff climbout : intermediate altitude
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tower : vny.tower
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	climbout : takeoff climbout : initial climbout : intermediate altitude
Flight Plan	VFR
Person 1
Affiliation	company : air taxi
Function	flight crew : first officer
Qualification	pilot : atp pilot : cfi pilot : multi engine
Experience	flight time last 90 days : 150 flight time total : 14800 flight time type : 1300
ASRS Report	598651
Person 2
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : nmac
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : took evasive action
Miss Distance	horizontal : 50 vertical : 50
Supplementary
Problem Areas	ATC Human Performance Airport Environmental Factor Flight Crew Human Performance
Primary Problem	Ambiguous

Narrative:

We were cleared for takeoff on vny runway 16R. Wind reported 110 degrees at 10 KTS. Cessna had been cleared for takeoff on runway 16L, and we were advised the cessna was advised we would be taking off and climbing off his right side. Cessna took off as we taxied into position for takeoff. Immediately after takeoff, after our initial flap retraction, I looked up from the flap indicator and saw us rapidly overtaking the cessna, which had been blown by the crosswind into our flight path. At this time, the cessna was co-altitude, about 300 ft ahead, and very slightly left of the nose. I called 'watch the cessna.' the captain raised the nose a little higher, and we passed the cessna very close on his right, a little above his altitude. We were equipped with tcasi, but got no TA. ATC should consider the effect a crosswind might have on a light aircraft (which is more likely to make an insufficient correction) before clearing a higher performance aircraft to take off on a close parallel runway. An overtake is inevitable, and reduced maneuverability at low speeds and altitudes in a high performance aircraft make collision avoidance difficult, if necessary.

Original NASA ASRS Text

Title: G159 EXPERIENCED NMAC WITH C172 DEP FROM PARALLEL RWY AT VNY.

Narrative: WE WERE CLRED FOR TKOF ON VNY RWY 16R. WIND RPTED 110 DEGS AT 10 KTS. CESSNA HAD BEEN CLRED FOR TKOF ON RWY 16L, AND WE WERE ADVISED THE CESSNA WAS ADVISED WE WOULD BE TAKING OFF AND CLBING OFF HIS R SIDE. CESSNA TOOK OFF AS WE TAXIED INTO POS FOR TKOF. IMMEDIATELY AFTER TKOF, AFTER OUR INITIAL FLAP RETRACTION, I LOOKED UP FROM THE FLAP INDICATOR AND SAW US RAPIDLY OVERTAKING THE CESSNA, WHICH HAD BEEN BLOWN BY THE XWIND INTO OUR FLT PATH. AT THIS TIME, THE CESSNA WAS CO-ALT, ABOUT 300 FT AHEAD, AND VERY SLIGHTLY L OF THE NOSE. I CALLED 'WATCH THE CESSNA.' THE CAPT RAISED THE NOSE A LITTLE HIGHER, AND WE PASSED THE CESSNA VERY CLOSE ON HIS R, A LITTLE ABOVE HIS ALT. WE WERE EQUIPPED WITH TCASI, BUT GOT NO TA. ATC SHOULD CONSIDER THE EFFECT A XWIND MIGHT HAVE ON A LIGHT ACFT (WHICH IS MORE LIKELY TO MAKE AN INSUFFICIENT CORRECTION) BEFORE CLRING A HIGHER PERFORMANCE ACFT TO TAKE OFF ON A CLOSE PARALLEL RWY. AN OVERTAKE IS INEVITABLE, AND REDUCED MANEUVERABILITY AT LOW SPDS AND ALTS IN A HIGH PERFORMANCE ACFT MAKE COLLISION AVOIDANCE DIFFICULT, IF NECESSARY.

Data retrieved from NASA's ASRS site as of July 2007 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.