Narrative:

My instructor and I were conducting familiarization and training flts in a TBM700 and were proceeding from the north to french valley airport (F70) for landing, where the winds were favoring runway 18. We were receiving TA's from march approach control. Approximately 12 mi to the north of the field we terminated advisories to switch to unicom. Since it is a busy uncontrolled field and the tbm is relatively fast in the traffic pattern, we briefed the most appropriate pattern entry procedure. In lieu of a midfield crosswind entry or a crosswind entry, we elected to do a standard 45 degree entry for a left downwind of runway 18. There is a small reservoir about 5 mi to the east of the field that we overflew with the intentions of dropping to pattern altitude and making a 135 degree turn in order to enter a 3 mi 45 degree approach to the downwind. We continually referred to the TCASII as a backup for traffic avoidance. Out of the corner of my eye, I caught movement from below the airplane and noticed an aerobatic aircraft (an extra or a sukhoi) rapidly climbing towards our position in a vertical maneuver. We broke to the right just as the other aircraft entered a spin following the vertical penetration. The aerobatic plane never appeared on the TCASII. We apparently also surprised the aerobatic pilot because after we landed at F70, she also landed and was abusive on the radio. The instructor with whom I was flying was both an airshow pilot and designated check airman for other aerobatic performers. He was not aware of an aerobatic box in the area where this incident took place. I am not certain that any far's were violated in this incident, though I do not think it was a great idea for the other pilot to be performing aerobatics in such close proximity to the airport. For me, even in a well equipped plane with TCASII, it drives home the importance of see and avoid. The other airplane may not even have a transponder. I have also subsequently learned that the recommended pattern entry from the north for runway 18 at F70 is to cross midfield to enter the pattern. If there is a local custom of using the adjacent reservoir for aerobatic practice, this midfield crossover would help a pilot clear of this area.

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Original NASA ASRS Text

Title: NMAC BTWN A TBM700 DSNDING THROUGH 3500 FT MSL TO ENTER AN UNCTLED TFC PATTERN AND AN AEROBATIC SMA CLBING VERTLY DURING AN AEROBATIC MANEUVER.

Narrative: MY INSTRUCTOR AND I WERE CONDUCTING FAMILIARIZATION AND TRAINING FLTS IN A TBM700 AND WERE PROCEEDING FROM THE N TO FRENCH VALLEY ARPT (F70) FOR LNDG, WHERE THE WINDS WERE FAVORING RWY 18. WE WERE RECEIVING TA'S FROM MARCH APCH CTL. APPROX 12 MI TO THE N OF THE FIELD WE TERMINATED ADVISORIES TO SWITCH TO UNICOM. SINCE IT IS A BUSY UNCTLED FIELD AND THE TBM IS RELATIVELY FAST IN THE TFC PATTERN, WE BRIEFED THE MOST APPROPRIATE PATTERN ENTRY PROC. IN LIEU OF A MIDFIELD XWIND ENTRY OR A XWIND ENTRY, WE ELECTED TO DO A STANDARD 45 DEG ENTRY FOR A L DOWNWIND OF RWY 18. THERE IS A SMALL RESERVOIR ABOUT 5 MI TO THE E OF THE FIELD THAT WE OVERFLEW WITH THE INTENTIONS OF DROPPING TO PATTERN ALT AND MAKING A 135 DEG TURN IN ORDER TO ENTER A 3 MI 45 DEG APCH TO THE DOWNWIND. WE CONTINUALLY REFERRED TO THE TCASII AS A BACKUP FOR TFC AVOIDANCE. OUT OF THE CORNER OF MY EYE, I CAUGHT MOVEMENT FROM BELOW THE AIRPLANE AND NOTICED AN AEROBATIC ACFT (AN EXTRA OR A SUKHOI) RAPIDLY CLBING TOWARDS OUR POS IN A VERTICAL MANEUVER. WE BROKE TO THE R JUST AS THE OTHER ACFT ENTERED A SPIN FOLLOWING THE VERT PENETRATION. THE AEROBATIC PLANE NEVER APPEARED ON THE TCASII. WE APPARENTLY ALSO SURPRISED THE AEROBATIC PLT BECAUSE AFTER WE LANDED AT F70, SHE ALSO LANDED AND WAS ABUSIVE ON THE RADIO. THE INSTRUCTOR WITH WHOM I WAS FLYING WAS BOTH AN AIRSHOW PLT AND DESIGNATED CHK AIRMAN FOR OTHER AEROBATIC PERFORMERS. HE WAS NOT AWARE OF AN AEROBATIC BOX IN THE AREA WHERE THIS INCIDENT TOOK PLACE. I AM NOT CERTAIN THAT ANY FAR'S WERE VIOLATED IN THIS INCIDENT, THOUGH I DO NOT THINK IT WAS A GREAT IDEA FOR THE OTHER PLT TO BE PERFORMING AEROBATICS IN SUCH CLOSE PROX TO THE ARPT. FOR ME, EVEN IN A WELL EQUIPPED PLANE WITH TCASII, IT DRIVES HOME THE IMPORTANCE OF SEE AND AVOID. THE OTHER AIRPLANE MAY NOT EVEN HAVE A XPONDER. I HAVE ALSO SUBSEQUENTLY LEARNED THAT THE RECOMMENDED PATTERN ENTRY FROM THE N FOR RWY 18 AT F70 IS TO CROSS MIDFIELD TO ENTER THE PATTERN. IF THERE IS A LCL CUSTOM OF USING THE ADJACENT RESERVOIR FOR AEROBATIC PRACTICE, THIS MIDFIELD CROSSOVER WOULD HELP A PLT CLR OF THIS AREA.

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.