Narrative:

The prearranged formation flight took place within a class C control zone and was coordinated by the pilot of the lead aircraft of the overall formation. This lead aircraft was assigned a discrete code and was in communication with approach control during the flight. Each flight had to position itself to arrive over the target in trail and within a reasonable distance of the flight ahead. The flight was fully briefed by all pilots prior to takeoff. The last flight was the slowest of the 6 flts and had to circle inside of the flight paths of the other flts. The subject aircraft were on the right wing on the inside of a clockwise turn. The lead aircraft increased its bank angle significantly to complete the turn and as a result reduced speed. This led to the subject aircraft; the innermost of the 6 aircraft; being unable to reduce speed quickly enough on the inside of the turn with the visibility of the formation becoming blocked by the high wing of the subject aircraft. The pilot of the subject aircraft took evasive action as previously briefed and radioed that he was leaving the formation. The evasive action taken was to rapidly descend away from the other aircraft. As a result the aircraft came within 250 ft of the ground/structures for a short period of time before visual contact was regained with the formation and position rejoined. No persons or structures were endangered despite the lower than planned altitude and the evasive maneuvers were completed safely as briefed.

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Original NASA ASRS Text

Title: LIGHT SPORT PILOT IN PLANNED FORMATION FLIGHT; REPORTS EVASIVE DESCENT WHEN FORMATION TURNS TOO STEEPLY IN HIS DIRECTION. REPORTER DESCENDS WITHIN 250 FEET OF POPULATED AREA BEFORE RECOVERY.

Narrative: THE PREARRANGED FORMATION FLT TOOK PLACE WITHIN A CLASS C CTL ZONE AND WAS COORDINATED BY THE PLT OF THE LEAD ACFT OF THE OVERALL FORMATION. THIS LEAD ACFT WAS ASSIGNED A DISCRETE CODE AND WAS IN COM WITH APCH CTL DURING THE FLT. EACH FLT HAD TO POS ITSELF TO ARRIVE OVER THE TARGET IN TRAIL AND WITHIN A REASONABLE DISTANCE OF THE FLT AHEAD. THE FLT WAS FULLY BRIEFED BY ALL PLTS PRIOR TO TKOF. THE LAST FLT WAS THE SLOWEST OF THE 6 FLTS AND HAD TO CIRCLE INSIDE OF THE FLT PATHS OF THE OTHER FLTS. THE SUBJECT ACFT WERE ON THE R WING ON THE INSIDE OF A CLOCKWISE TURN. THE LEAD ACFT INCREASED ITS BANK ANGLE SIGNIFICANTLY TO COMPLETE THE TURN AND AS A RESULT REDUCED SPD. THIS LED TO THE SUBJECT ACFT; THE INNERMOST OF THE 6 ACFT; BEING UNABLE TO REDUCE SPD QUICKLY ENOUGH ON THE INSIDE OF THE TURN WITH THE VISIBILITY OF THE FORMATION BECOMING BLOCKED BY THE HIGH WING OF THE SUBJECT ACFT. THE PLT OF THE SUBJECT ACFT TOOK EVASIVE ACTION AS PREVIOUSLY BRIEFED AND RADIOED THAT HE WAS LEAVING THE FORMATION. THE EVASIVE ACTION TAKEN WAS TO RAPIDLY DSND AWAY FROM THE OTHER ACFT. AS A RESULT THE ACFT CAME WITHIN 250 FT OF THE GND/STRUCTURES FOR A SHORT PERIOD OF TIME BEFORE VISUAL CONTACT WAS REGAINED WITH THE FORMATION AND POS REJOINED. NO PERSONS OR STRUCTURES WERE ENDANGERED DESPITE THE LOWER THAN PLANNED ALT AND THE EVASIVE MANEUVERS WERE COMPLETED SAFELY AS BRIEFED.

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