Narrative:

The flight in question was a solo cross country. As I approached corona I switched to the CTAF. There was a lot of activity. I called 'at the prado dam,' then 'left-hand downwind for south helipads midfield from the south.' then 'base to final, south helipads.' I landed on the middle 1 of the 3 pads, set down, and announced 'will takeoff from south pads for a left crosswind, south departure.' I made the takeoff, announced 'turning left crosswind for a south departure,' cleared (visually) to the left, and started the turn. As I brought my eyes back to straight ahead, a red and white R22 crossed in front of me, right to left, about 150 ft away, about 20 ft higher, in a left, level or descending turn with a heading about 30 degrees to the left of my heading. At no time did I hear any other helicopter reporting in the corona circuit, nor any aircraft announcing a l-hand pattern. I did not check the runway visually before takeoff, runway 25 was in use, it is to the north of the helipads (to my right on takeoff), but buildings between the helipads and the runway block the view between helipads and runway until at 50 ft AGL. The other helicopter was in a left, level or descending turn, at a higher speed than I had (I had 50 KIAS), coming from my right. It had to either have taken off from the runway or airplane ramp/taxiway, or have made a low pass, touch-and-go, or go around to either runway or airplane ramp/taxiway. From his course and steady turn, I think the pilot never saw me. I observed no evasive action. By the time I saw him, he was in front of me, pulling away and moving to my left, so I took no evasive action either.

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Original NASA ASRS Text

Title: A ROBINSON R22 PLT HAD AN NMAC WITH ANOTHER R22 AT THE HELIPADS AT L66, A NON TWR ARPT CTAF.

Narrative: THE FLT IN QUESTION WAS A SOLO XCOUNTRY. AS I APCHED CORONA I SWITCHED TO THE CTAF. THERE WAS A LOT OF ACTIVITY. I CALLED 'AT THE PRADO DAM,' THEN 'L-HAND DOWNWIND FOR S HELIPADS MIDFIELD FROM THE S.' THEN 'BASE TO FINAL, S HELIPADS.' I LANDED ON THE MIDDLE 1 OF THE 3 PADS, SET DOWN, AND ANNOUNCED 'WILL TKOF FROM S PADS FOR A L XWIND, S DEP.' I MADE THE TKOF, ANNOUNCED 'TURNING L XWIND FOR A S DEP,' CLRED (VISUALLY) TO THE L, AND STARTED THE TURN. AS I BROUGHT MY EYES BACK TO STRAIGHT AHEAD, A RED AND WHITE R22 CROSSED IN FRONT OF ME, R TO L, ABOUT 150 FT AWAY, ABOUT 20 FT HIGHER, IN A L, LEVEL OR DSNDING TURN WITH A HDG ABOUT 30 DEGS TO THE L OF MY HDG. AT NO TIME DID I HEAR ANY OTHER HELI RPTING IN THE CORONA CIRCUIT, NOR ANY ACFT ANNOUNCING A L-HAND PATTERN. I DID NOT CHK THE RWY VISUALLY BEFORE TKOF, RWY 25 WAS IN USE, IT IS TO THE N OF THE HELIPADS (TO MY R ON TKOF), BUT BUILDINGS BTWN THE HELIPADS AND THE RWY BLOCK THE VIEW BTWN HELIPADS AND RWY UNTIL AT 50 FT AGL. THE OTHER HELI WAS IN A L, LEVEL OR DSNDING TURN, AT A HIGHER SPD THAN I HAD (I HAD 50 KIAS), COMING FROM MY R. IT HAD TO EITHER HAVE TAKEN OFF FROM THE RWY OR AIRPLANE RAMP/TXWY, OR HAVE MADE A LOW PASS, TOUCH-AND-GO, OR GAR TO EITHER RWY OR AIRPLANE RAMP/TXWY. FROM HIS COURSE AND STEADY TURN, I THINK THE PLT NEVER SAW ME. I OBSERVED NO EVASIVE ACTION. BY THE TIME I SAW HIM, HE WAS IN FRONT OF ME, PULLING AWAY AND MOVING TO MY L, SO I TOOK NO EVASIVE ACTION EITHER.

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.