Narrative:

On a VFR flight from sjc to tracy municipal airport (O36) in partial fulfillment of solo requirements for helicopter rating. After reaching tracy and making initial approach, I decided to stay in pattern for practice as traffic was light. Previously I had experienced some radio static and difficulty communicating with sjc tower (don't know if radio was a factor in event). I made all position announcements in the pattern, per instructions in aim. On last pattern, I was concentrating on establishing a good glide path on final (was approximately 400' AGL) using the VASI when out of the corner of my left eye I noticed the shadow of an aircraft converging with my flight path. I looked frantically to the left, at and above my altitude, but could see no aircraft. Then I looked down and saw a white bi-plane crossing below me about 200' and cutting in front on final. Although I could have come to an air hover and stopped approach (one advantage of a chopper), I broke off to the right and re-entered final from a right base leg. I never heard anything from the bi-plane, and assumed he was a no radio aircraft. Contributing factors: the aim enjoins helicopters to 'avoid the flow of fixed-wing traffic', but this is not a realistic possibility at all airports (at tracy, for example, all patterns are lefthand, and the lcls don't want aircraft in right patterns). I was concentrating too much on trying to get the helicopter on the VASI and not looking around (as we are taught) for the local yokel coming straight in. Either the bi-plane had no radio, or just wasn't announcing (an small aircraft C had no difficulty hearing me on an earlier approach). I believe that he saw me because he made a clear cut-in-front maneuver, from below and to the left. Granted I was at about 30-40 KTS indicated on final (normal approach speed for this helicopter), but he had no business getting so impatient as to jeopardize safety. Have resolved for the future that if I am in similar pattern work again, that I'll fly faster approach speeds (those nearer the aircraft speeds) so as to fit in better with the flow of traffic, unless I have the pattern to myself. I'm finding that most aircraft pilots have a real 'attitude' about helicopters, and think they're god almighty. But aircraft pilots also have trouble seeing helicopters, sometimes, but not apparently in this event. Callback conversation with reporter revealed the following: reporter stated that the traffic situation was very light and the presence of the NORDO bi-plane surprised reporter. It was, in fact, the only other aircraft in the pattern so reporter was understandably disturbed by the other pilot's inappropriate quick turn in front of reporter's helicopter. The radio was getting scratchy on transmission but as the other aircraft was almost surely a non radio type aircraft that had nothing to do with the event. The VASI was being used to establish a standard glide path towards the runway, a useful training tool or device.

Related reports:

Google
 

Original NASA ASRS Text

Title: NMAC COLLISION ON FINAL APCH BETWEEN FIXED WING ACFT AND ROTARY WINGED ACFT. NON TWR ARPT WITH CTAF UNICOM.

Narrative: ON A VFR FLT FROM SJC TO TRACY MUNI ARPT (O36) IN PARTIAL FULFILLMENT OF SOLO REQUIREMENTS FOR HELI RATING. AFTER REACHING TRACY AND MAKING INITIAL APCH, I DECIDED TO STAY IN PATTERN FOR PRACTICE AS TFC WAS LIGHT. PREVIOUSLY I HAD EXPERIENCED SOME RADIO STATIC AND DIFFICULTY COMMUNICATING WITH SJC TWR (DON'T KNOW IF RADIO WAS A FACTOR IN EVENT). I MADE ALL POSITION ANNOUNCEMENTS IN THE PATTERN, PER INSTRUCTIONS IN AIM. ON LAST PATTERN, I WAS CONCENTRATING ON ESTABLISHING A GOOD GLIDE PATH ON FINAL (WAS APPROX 400' AGL) USING THE VASI WHEN OUT OF THE CORNER OF MY LEFT EYE I NOTICED THE SHADOW OF AN ACFT CONVERGING WITH MY FLT PATH. I LOOKED FRANTICALLY TO THE LEFT, AT AND ABOVE MY ALT, BUT COULD SEE NO ACFT. THEN I LOOKED DOWN AND SAW A WHITE BI-PLANE XING BELOW ME ABOUT 200' AND CUTTING IN FRONT ON FINAL. ALTHOUGH I COULD HAVE COME TO AN AIR HOVER AND STOPPED APCH (ONE ADVANTAGE OF A CHOPPER), I BROKE OFF TO THE RIGHT AND RE-ENTERED FINAL FROM A RIGHT BASE LEG. I NEVER HEARD ANYTHING FROM THE BI-PLANE, AND ASSUMED HE WAS A NO RADIO ACFT. CONTRIBUTING FACTORS: THE AIM ENJOINS HELIS TO 'AVOID THE FLOW OF FIXED-WING TFC', BUT THIS IS NOT A REALISTIC POSSIBILITY AT ALL ARPTS (AT TRACY, FOR EXAMPLE, ALL PATTERNS ARE LEFTHAND, AND THE LCLS DON'T WANT ACFT IN RIGHT PATTERNS). I WAS CONCENTRATING TOO MUCH ON TRYING TO GET THE HELI ON THE VASI AND NOT LOOKING AROUND (AS WE ARE TAUGHT) FOR THE LOCAL YOKEL COMING STRAIGHT IN. EITHER THE BI-PLANE HAD NO RADIO, OR JUST WASN'T ANNOUNCING (AN SMA C HAD NO DIFFICULTY HEARING ME ON AN EARLIER APCH). I BELIEVE THAT HE SAW ME BECAUSE HE MADE A CLEAR CUT-IN-FRONT MANEUVER, FROM BELOW AND TO THE LEFT. GRANTED I WAS AT ABOUT 30-40 KTS INDICATED ON FINAL (NORMAL APCH SPEED FOR THIS HELI), BUT HE HAD NO BUSINESS GETTING SO IMPATIENT AS TO JEOPARDIZE SAFETY. HAVE RESOLVED FOR THE FUTURE THAT IF I AM IN SIMILAR PATTERN WORK AGAIN, THAT I'LL FLY FASTER APCH SPEEDS (THOSE NEARER THE ACFT SPEEDS) SO AS TO FIT IN BETTER WITH THE FLOW OF TFC, UNLESS I HAVE THE PATTERN TO MYSELF. I'M FINDING THAT MOST ACFT PLTS HAVE A REAL 'ATTITUDE' ABOUT HELIS, AND THINK THEY'RE GOD ALMIGHTY. BUT ACFT PLTS ALSO HAVE TROUBLE SEEING HELIS, SOMETIMES, BUT NOT APPARENTLY IN THIS EVENT. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: REPORTER STATED THAT THE TFC SITUATION WAS VERY LIGHT AND THE PRESENCE OF THE NORDO BI-PLANE SURPRISED REPORTER. IT WAS, IN FACT, THE ONLY OTHER ACFT IN THE PATTERN SO REPORTER WAS UNDERSTANDABLY DISTURBED BY THE OTHER PLT'S INAPPROPRIATE QUICK TURN IN FRONT OF REPORTER'S HELI. THE RADIO WAS GETTING SCRATCHY ON XMISSION BUT AS THE OTHER ACFT WAS ALMOST SURELY A NON RADIO TYPE ACFT THAT HAD NOTHING TO DO WITH THE EVENT. THE VASI WAS BEING USED TO ESTABLISH A STANDARD GLIDE PATH TOWARDS THE RWY, A USEFUL TRAINING TOOL OR DEVICE.

Data retrieved from NASA's ASRS site as of August 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.