The SR-91 Aurora has been at the center of military aviation for so many years and remains a point of ongoing speculation. This aircraft can supposedly reach altitude at hypersonic speeds beyond Mach 5; the uncertainty of its development is unknown. Some have even claimed that this Aurora is the legitimate successor to sweep the role of SR-71 Blackbird, which was retired due to its extremely high operating cost ranging between $200 and $300 million per year.
In 1985, “Aurora” first captured the public imagination as a line item in a “black program” request for the defense budget. The speculation that something was developing a whole new generation of fighter aircraft was rife. But some say that “Aurora” would have been nothing more than a codename for the B-2 Spirit, a kind of stealth bomber that showed its face towards the close of the 1980s.
DefenceAviation.com referred to the SR-91 Aurora as a “theory,” and quoted a 2006 British Ministry of Defence report that stated the US Air Force might have an option within its “capability” plan for a Mach 4-6 supersonic vehicle, although no such program was in evidence. Probably the only credible sighting was by an engineer named Chris Gibson, who claimed to have seen a triangular-shaped aircraft over the North Sea in 1989. This again could have been the B-2 or the F117 Nighthawk, which were operational then.
Another circumstantial evidence pertains to the “sky quakes” over Los Angeles during the early 1990s. These series of loud booms were reportedly hypothesized from a hypersonic aircraft operating out of Groom Lake, Nevada. This, of course, is speculation.
If it had ever existed, the SR-91 Aurora would by now be rendered obsolete given the advances that have been previously described in spy satellites and reconnaissance drones that could do the same work without the manning risks. The possibility that the Aurora was developed is even further weakened by the development of the SR-72 Son of Blackbird program.
Former Lockheed Martin Skunk Works chief Ben Rich similarly dismissed the Aurora hypothesis in his memoir. He explained that “Aurora” was just a codename for the funding of the competition for the B-2, not for any hypersonic-plane project.
The Aurora remains in the popular imagination, even though it was never concretely seen. The Department of Defense never acknowledged its existence; sightings came in at a small, unreliable number. If indeed it ever left the drawing board, the SR-91 Aurora will stand out as one of the most mysterious subjects in the history of military aviation.