High performance small aircraft passes over aircraft departing opposite direction on same runway.

Attributes
ACN	762396
Time
Date	200711
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : o41.airport
State Reference	CA
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Lancair Undifferentiated
Operating Under FAR Part	Part 91
Flight Phase	ground : takeoff roll
Flight Plan	None
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Aircraft Low Wing 1 Eng Fixed Gear
Flight Phase	ground : takeoff roll
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : private
Experience	flight time last 90 days : 30 flight time total : 1350 flight time type : 1100
ASRS Report	762396
Events
Anomaly	conflict : ground critical non adherence : published procedure other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Miss Distance	horizontal : 0 vertical : 100
Supplementary
Problem Areas	Environmental Factor Flight Crew Human Performance Airport
Primary Problem	Ambiguous

Narrative:

Winds at O41 (watts-woodland) favored runway 36 (approximately 340 degrees at 7 KTS). After performing a run-up; I called my departure from runway 36 with a left downwind departure. 1/2 way into my takeoff roll; a cirrus (possibly a columbia) announced a departure from runway 18 and proceeded onto the runway. I pointed out via radio that I was currently departing runway 36. I elected to continue the takeoff in case the other aircraft did not stop. Given my speed at the time; I knew I would clear the other aircraft. I would not have been able to stop in time to avoid a collision if the other aircraft continued with its departure. The run-up areas are not visible from each other.

Original NASA ASRS Text

Title: HIGH PERFORMANCE SMA PASSES OVER ACFT DEPARTING OPPOSITE DIRECTION ON SAME RWY.

Narrative: WINDS AT O41 (WATTS-WOODLAND) FAVORED RWY 36 (APPROX 340 DEGS AT 7 KTS). AFTER PERFORMING A RUN-UP; I CALLED MY DEP FROM RWY 36 WITH A L DOWNWIND DEP. 1/2 WAY INTO MY TKOF ROLL; A CIRRUS (POSSIBLY A COLUMBIA) ANNOUNCED A DEP FROM RWY 18 AND PROCEEDED ONTO THE RWY. I POINTED OUT VIA RADIO THAT I WAS CURRENTLY DEPARTING RWY 36. I ELECTED TO CONTINUE THE TKOF IN CASE THE OTHER ACFT DID NOT STOP. GIVEN MY SPD AT THE TIME; I KNEW I WOULD CLR THE OTHER ACFT. I WOULD NOT HAVE BEEN ABLE TO STOP IN TIME TO AVOID A COLLISION IF THE OTHER ACFT CONTINUED WITH ITS DEP. THE RUN-UP AREAS ARE NOT VISIBLE FROM EACH OTHER.

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.