Date: 201907
Local time of day: 0601-1200
Weather elements / visibility: 10
Light: Daylight
Aircraft: M-20 Series Undifferentiated or Other Model
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Cruise
Airspace: Class G ZZZ
Second aircraft: M-20 Series Undifferentiated or Other Model
Reporter organization: Personal
Reporter function: Pilot Flying; Single Pilot
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Flight Instructor; Flight Crew Commercial
Human factors: Communication Breakdown; Situational Awareness
Second reporter function: Single Pilot
Anomaly: Aircraft Equipment Problem Less Severe; Conflict NMAC; Inflight Event / Encounter Object
Detector: Person Flight Crew
When detected: Routine Inspection
Result: Aircraft Aircraft Damaged; Flight Crew Took Evasive Action
Contributing factors: Aircraft; Airspace Structure; Human Factors; Procedure
Primary problem: Procedure

Narrative: In VFR weather I departed ZZZ in Aircraft X; [a] Mooney; as second aircraft in Whiskey element of two aircraft. Lead Aircraft was Aircraft Y ('W Lead'). We had briefed joining on the two-ship element ahead as '3' and '4' in 'finger-four' formation. As briefed; after takeoff I crossed-under from left to right of Lead Aircraft to join in normal fingertip on Whiskey Lead's right. Whiskey Lead began closing on the Victor element ahead. While maintaining position; I experienced significant wake vortices from preceding 60-odd aircraft. I was moved above Whiskey Lead and briefly lost sight. I deconflicted turning away and descending from the element. I heard 'Tail' (the last aircraft in our formation traveling behind Whiskey element) ask Whiskey Lead if he had 'kissed me off' (released me from the formation) and I heard Whiskey lead respond 'no.' I visually reacquired Whiskey Lead to my left. 'Tail' asked would I rejoin and I replied 'yes.' I rejoined Whiskey Lead and proceeded uneventfully to ZZZ1 for landing as briefed. At no time did l either observe or experience any flight control issues during the flight; landing or taxi. I was unaware the aircraft had touched until after landing; when I exited the aircraft and observed damage to my rudder trim tab; which I pointed out to Whiskey Lead pilot. We called the NTSB and made a verbal report.


Second narrative: In VFR weather I departed ZZZ in Aircraft Y; a Mooney M20; as lead of a two-ship Whiskey element (Lead Aircraft). Second ship/wingman was Aircraft X (Wing Aircraft). We had briefed joining on the two-ship element ahead as '3' and '4' in 'finger-four' formation. As briefed; after takeoff Wing Aircraft crossed-under from left to right of Lead Aircraft. Once he was in position; l closed on the right of the 'No. 1' aircraft of two-ship Victor element ahead. As l was maneuvering towards the '1' lead aircraft from about 200 yards; my passenger yelled 'look out.' I looked to my right and saw Wing Aircraft in front of me; slightly above; and slowing. I immediately deconflicted from both Wing Aircraft and the '1' lead aircraft by ruddering left and descending away while maintaining sight of all three aircraft. Once clear; I rejoined to original briefed position as '3' on right of '1' lead aircraft and watched as Wing Aircraft rejoined on my right. Nearing our destination (ZZZ1); I separated from the lead element to achieve proper element landing distance; crossed Wing Aircraft back to the left so I could maintain sight of him and '1' lead aircraft element and landed normally. At no time did l either observe or experience any flight control issues during the flight; landing or taxi. I was unaware the aircraft had touched until after landing; when pilot of the Wing Aircraft identified damage to his rudder and then we identified damage to my right wingtip leading edge. We called the NTSB and made a verbal report.


Synopsis: Mooney 20 pilots reported a minor inflight collision while formation flying.