How the TR-3 designation came up in publications is unclear. It is clearly not a continuation of the R-for-Reconnaissance series, since ER-2 (NASA designation for U-2 aircraft modified for earth resources study) stood for "Earth Resources", not "Electronic Reconnaissance". It's therefore possible that TR-3 is merely a corruption of Tier III, a name given to a cancelled large reconnaissance UAV flying wing designed in the timeframe of alleged sightings of the Black Manta (circa 1988/1990). (The Tier III Minus program that resulted in the unsuccessful RQ-3 was a scaled-down derivative of the original Tier III.)
Because there is no evidence to support TR-3's existence, it is possible that the mysterious flying wing sightings associated with Black Manta could be a technology demonstrator for a potential new-generation tactical reconnaissance aircraft. This contention is supported by USAF sources in the late 1980s confirming that the US had no short-term plans to develop a low-observable U-2 successor.
Another candidate for the alleged spyplane is a design from Teledyne Ryan, patented in the United States on April 26, 1977, under number 4,019,699. This aircraft of low observability as it is called, was invented by Robert W. Wintersdorff and George R. Cota, employees at Teledyne Ryan, a firm specialized in building unmanned reconnaissance aircraft. On May 10, 1977, a design of an aircraft was patented by Teledyne Ryan under number Des. 244,265, and closely resembles the earlier mentioned example. This design was made by Waldo Virgil Opfer. The first design is unmanned, the second one manned. Whether one of these designs is related to the above-mentioned TR-3A is not positively identified, but it is a coincidence that TR also stands for Teledyne Ryan. Teledyne Ryan was procured by Northrop Grumman in 1999. The Teledyne Ryan designs also strongly resemble the unidentified flying objects photographed in Belgium in 1989/1990,[original research?] which were chased by the Belgian Air Force and seen by hundreds of people in what is called the Belgian UFO wave.