Narrative:

Myself and 2 friends, flying 3 small aircraft's, departed separately from santa maria public airport intending to practice formation flying in a local practice area about 10 mi west of santa maria over an unpopulated stretch of beach. (I will refer to our aircraft as aircraft 1, 2 or 3. Myself flying aircraft #1, and my friends flying 2 and 3.) the pilot of aircraft #2 and I have flown together, usually in formation for years without incident. The pilot of aircraft #3 was on her first formation flight. As we entered the practice area #1 and #2 were in formation at about 3000' with #3 observing from about a thousand feet above and behind. As we approached the beach, we observed another, same type small aircraft #4, circling point sal at less than 1000'. The other aircraft remained low and north of our position and appeared to be no factor for our flight. While flying over the beach at 2500' MSL, aircraft #2 and I started a tail chase with aircraft #3 still observing from above. Aircraft #2 was on my tail when I executed a maneuver which caused him to lose sight of me and placed my plane on #2's tail. I had visual contact with aircraft #2 and assumed he knew I was on his tail. The pilot of aircraft #2, however, had spotted aircraft #4, which was now diving at aircraft #2 from #2's 2 O'clock position. The pilot of aircraft #2 mistook aircraft #4 for my plane and when aircraft #4 made a sharp right turn in front of #2's nose, #2 turned left onto #4's tail. From #2's 6 O'clock position, I realized what was happening and told #2 to disengage over our air-to-air frequency. #2 made a right 180 degree turn and I formed up with #2 and our 3 aircraft left the area and landed at oceano airport. While in the pattern at oceano, aircraft #4 contacted me on the CTAF. He asked if we were the planes maneuvering near pt sal and I said we were and I apologized for the mistaken identity. He replied 'don't worry about it' or words to that effect. Aircraft #3 was unable to warn us that the 4TH aircraft was in the area because of glare and she saw #4 at about the same time #1 and #2 did. We all thought it looked like #4 was trying to enter the tail chase because he dove on our flight, then made an evasive type turn into, instead of away from, #2.

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Original NASA ASRS Text

Title: SMA'S PRACTICING FORMATION FLYING AND TAIL CHASE. ONE HAS NMAC WITH ANOTHER SMA TRYING TO JOIN THE ACTIVITY.

Narrative: MYSELF AND 2 FRIENDS, FLYING 3 SMA'S, DEPARTED SEPARATELY FROM SANTA MARIA PUBLIC ARPT INTENDING TO PRACTICE FORMATION FLYING IN A LCL PRACTICE AREA ABOUT 10 MI W OF SANTA MARIA OVER AN UNPOPULATED STRETCH OF BEACH. (I WILL REFER TO OUR ACFT AS ACFT 1, 2 OR 3. MYSELF FLYING ACFT #1, AND MY FRIENDS FLYING 2 AND 3.) THE PLT OF ACFT #2 AND I HAVE FLOWN TOGETHER, USUALLY IN FORMATION FOR YEARS WITHOUT INCIDENT. THE PLT OF ACFT #3 WAS ON HER FIRST FORMATION FLT. AS WE ENTERED THE PRACTICE AREA #1 AND #2 WERE IN FORMATION AT ABOUT 3000' WITH #3 OBSERVING FROM ABOUT A THOUSAND FEET ABOVE AND BEHIND. AS WE APCHED THE BEACH, WE OBSERVED ANOTHER, SAME TYPE SMA #4, CIRCLING POINT SAL AT LESS THAN 1000'. THE OTHER ACFT REMAINED LOW AND N OF OUR POSITION AND APPEARED TO BE NO FACTOR FOR OUR FLT. WHILE FLYING OVER THE BEACH AT 2500' MSL, ACFT #2 AND I STARTED A TAIL CHASE WITH ACFT #3 STILL OBSERVING FROM ABOVE. ACFT #2 WAS ON MY TAIL WHEN I EXECUTED A MANEUVER WHICH CAUSED HIM TO LOSE SIGHT OF ME AND PLACED MY PLANE ON #2'S TAIL. I HAD VISUAL CONTACT WITH ACFT #2 AND ASSUMED HE KNEW I WAS ON HIS TAIL. THE PLT OF ACFT #2, HOWEVER, HAD SPOTTED ACFT #4, WHICH WAS NOW DIVING AT ACFT #2 FROM #2'S 2 O'CLOCK POSITION. THE PLT OF ACFT #2 MISTOOK ACFT #4 FOR MY PLANE AND WHEN ACFT #4 MADE A SHARP RIGHT TURN IN FRONT OF #2'S NOSE, #2 TURNED LEFT ONTO #4'S TAIL. FROM #2'S 6 O'CLOCK POSITION, I REALIZED WHAT WAS HAPPENING AND TOLD #2 TO DISENGAGE OVER OUR AIR-TO-AIR FREQ. #2 MADE A RIGHT 180 DEG TURN AND I FORMED UP WITH #2 AND OUR 3 ACFT LEFT THE AREA AND LANDED AT OCEANO ARPT. WHILE IN THE PATTERN AT OCEANO, ACFT #4 CONTACTED ME ON THE CTAF. HE ASKED IF WE WERE THE PLANES MANEUVERING NEAR PT SAL AND I SAID WE WERE AND I APOLOGIZED FOR THE MISTAKEN IDENTITY. HE REPLIED 'DON'T WORRY ABOUT IT' OR WORDS TO THAT EFFECT. ACFT #3 WAS UNABLE TO WARN US THAT THE 4TH ACFT WAS IN THE AREA BECAUSE OF GLARE AND SHE SAW #4 AT ABOUT THE SAME TIME #1 AND #2 DID. WE ALL THOUGHT IT LOOKED LIKE #4 WAS TRYING TO ENTER THE TAIL CHASE BECAUSE HE DOVE ON OUR FLT, THEN MADE AN EVASIVE TYPE TURN INTO, INSTEAD OF AWAY FROM, #2.

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.