There are 6 Tri-R Technologies TR-4 aircraft on the U.S. registry that TailWiki has a page for. Every one is built from the public FAA record — year, serial, engine, home base, and registration history — and owners and pilots add photos, trips, and stories on top. The ones listed here were built between 2009 and 2019.
N781SF
2019 Charles T Smith TR-4
Edgewood, TX
N71EJ
2016 Hanson Edwin L KIS TR4-TRI-R-TECHNO
Knoxville, TN
N844DK
2009 Kennedy David E KIS CRUISER TR-4
Syracuse, NY
N118EN
Nichols Edson H III KIS-CRUISER TR-4
Stuart, FL
N247BR
Robert A Reed TRI-R TECH TR-4
Huntsville, TX
N987VP
Krasinski Jerzy S CRUISER TR-4
Whiteville, NC