Amateur/Home Built/Experimental
Flight Crew Multiengine; Flight Crew Flight Instructor; Flight Crew Commercial; Flight Crew Instrument
Flight Crew Last 90 Days 74; Flight Crew Total 4500; Flight Crew Type 900
Situational Awareness; Distraction; Other / Unknown
Inflight Event / Encounter Other / Unknown
Aircraft Aircraft Damaged; Flight Crew Became Reoriented; Flight Crew Landed As Precaution
Human Factors; Procedure
During an Airshow; while flying the slot position in a 4-ship diamond formation; I overtook the leader (#1) and my propeller struck his tail spring. Half of each propeller blade was cut off/lost. Engine/propeller still producing adequate power/thrust. Both aircraft landed without further incident. Flight was conducted in conjunction with a Jet Truck as part of the Airshow. This truck has 3 jet engines and also large fire plumes coming out the top of the truck. The large heat signature affected the 4-ship flight flying over the top of the truck at approximately 50 feet. Also; the noise and speed of the oncoming Jet Truck affected my willingness to descend into the path of the oncoming truck to deconflict with my flight lead.  I needed to descend to miss my flight lead and did not feel I could do so due to the truck. Corrective actions: Higher altitude over the truck. No airshow smoke from #1 at low altitudes.
While in an airshow the slot aircraft propeller contacted the tailwheel boom of the lead aircraft during a low altitude jet truck race. The Team had completed a normal rejoin and was steady for the inbound run. Formation was in level upright flight. The flight was established in level flight at a set power setting. Slot described how he saw the truck directly in front and when he passed over it heard the jet 'booms'. He observed then that he had moved under the lead aircraft and rapidly pulled power to idle. The two wingmen commented how they saw the slot aircraft rapidly move forward. Lead stated that he felt his aircraft tail rise (evident in the post incident review of the photos); apparently from the bow wave effect of the slot aircraft. Contact was made at this point and the formation rose up and discontinued the act. Lead checked with the slot aircraft to ascertain if he had any control difficulties and if he could return to the airport. Slot advised he was making good power and engine was smooth during climbout. He was cleared off and a call to airboss was made to facilitate his immediate landing. Lead requested a visual inspection of his aircraft by a remaining wingman. He noted one tailwheel spring was missing. Lead advised air boss of missing spring. It was not clear until after parking all aircraft that a prop strike had occurred. While the slot pilot didn't remember entering lead's smoke; photographs taken during the event show the canopy partially obscured during the overtake.
Two pilots involved in a midair collision during a low altitude formation flight describe the circumstances that caused the event.