Last week, NASA Administrator Jared Isaacman cryptically teased plans for a new high- and fast-flying X-plane with a silhouette of an aircraft that immediately drew comparisons to the famed SR-71 Blackbird as a backdrop.

In our report, we looked at what it could mean, including the possibility of reviving the SR-71, or at least using it to inform or even cobble together a new airframe. Now it turns out that an SR-71 that had been on display at NASA’s Armstrong Flight Research Center for years is suspiciously missing.

Steve Trimble, ‘s defense editor and friend of , was first to report the disappearance of the former NASA SR-71, also known by the tail number 844, at Armstrong. That facility is collocated with Edwards Air Force Base in California. Trimble’s piece says that satellite imagery shows the jet has not been seen since at least May 17. The aircraft in question, which originally carried the U.S. Air Force serial number 61-7980, was the last Blackbird produced and the last one to fly, taking to the skies for the final time in 1999. “The current disposition of the aircraft is unclear, but sources suggest that the aircraft was moved into a hangar earlier this year for an inspection,” according to the story. “The presentation and the disappearance of the display SR-71S with the 844 tail number for NASA raises the possibility of a return-to-flight program after a more than 26-year-long hiatus.” The presentation mentioned above is the one NASA’s Isaacman gave last week at the annual All-In Summit in Los Angeles, California, during which he shared the SR-71-esque silhouette.

“The current disposition of the aircraft is unclear, but sources suggest that the aircraft was moved into a hangar earlier this year for an inspection,” according to the story. “The presentation and the disappearance of the display SR-71S with the 844 tail number for NASA raises the possibility of a return-to-flight program after a more than 26-year-long hiatus.” The presentation mentioned above is the one NASA’s Isaacman gave last week at the annual All-In Summit in Los Angeles, California, during which he shared the SR-71-esque silhouette.

“In the service of the first A [aeronautics] in NASA, we are rebuilding our X-plane fleet. The X-59 is researching quiet supersonic flight but it’s just the beginning,” he said at that time. “As NASA recommits to flight test and works alongside industry to push the boundaries of airframe and propulsion design, it will not be long before NASA once again is flying as high and as fast as we had in decades past, and then even more.” Isaacman has made expanding NASA’s X-plane fleets a top priority since taking charge of the agency last year. “You sure that’s a Blackbird?” the NASA administrator said during a live interview that immediately followed his remarks after the image was brought up, but did not offer any further clarification.

“NASA has a long history of building and flying experimental aircraft that push the boundaries of what is possible,” NASA told directly when asked for more information. “As Administrator Isaacman has said, we want to see more X-planes flying in the years ahead, developing the technologies that will allow us to fly higher, farther, and faster than we have in decades. We look forward to sharing more as those efforts progress.” We have reached back out to NASA in light of ‘s report.

“NASA has a long history of building and flying experimental aircraft that push the boundaries of what is possible,” NASA told directly when asked for more information. “As Administrator Isaacman has said, we want to see more X-planes flying in the years ahead, developing the technologies that will allow us to fly higher, farther, and faster than we have in decades. We look forward to sharing more as those efforts progress.” We have reached back out to NASA in light of ‘s report. As we wrote in our initial reporting on Isaacman’s comments: ‘s report today notes that tail number 844 would probably be the best available candidate for returning to flight status. In addition to being the last produced and the last to fly, NASA previously upgraded it, including with “an automated digital flight and inlet control system to virtually eliminate the Blackbird’s problem of violent engine unstarts at high speed.” It has also been sitting in a controlled area in the Mojave Desert that is great for preservation.

It is also worth pointing out here that Isaacman is personally aware of the time and resources it takes to reconstitute high-end vintage military aircraft. He founded private ‘red air’ aggressor firm Draken International making him once the owner of the world’s largest private air force stocked with old jets. His own private collection includes a demilitarized, ex-Ukrainian two-seat MiG-29UB that he flies regularly. He has also been working to restore a former Royal Air Force swing-wing Panavia Tornado F2 interceptor, which would be the most complex private military jet flying, if or when it returned to working condition.

At the same time, the SR-71 is in a completely different category, having been the very definition of a high-demand, low-density asset even at the very peak of its service life with the Air Force. Only 32 of these jets were ever built, and they were notoriously complex and expensive to operate and maintain. The aircraft’s Pratt & Whitney J58 turbojets ran on JP-7 fuel that is no longer in regular production. After 9/11, the possibility was raised of returning a Blackbird to service to support the Global War on Terror, but doing so was projected to cost between $40 and $45 million – and that was just two years after 844’s last flight.

There is also a possibility, in line with Isaacman’s comments last week, that 844 could re-merge in a substantially different, reworked form. There is even the potential it could be retrofitted for uncrewed, or at least pilot-optional, flight. Any such conversion effort would also be a major undertaking, as would sustaining the resulting bespoke jet. As we noted earlier, NASA could also use the SR-71 at Edwards to help inform other future designs.

At the same time, maybe this is all a coincidence and the SR-71 in question is getting some other form of TLC, but its months-long absence is certainly a curious development in light of the current push for new X-planes under Isaacman’s leadership. NASA has now provided with the following statement in response to our queries for more information about SR-71 tail number 844:

It has come to our attention that NASA Administrator Jared Isaacman made additional comments regarding the SR-71 at the EAA AirVenture airshow in July. “There was a time that a lot of the technology that you see demonstrated here in the F-22 Raptor, like thrust vectoring controls, fly-by-wire, was pioneered by NASA. This is during the days when we had X-planes that included the SR71 Blackbird,” Isaacman said during a speech at the event. “We’re rebuilding our X-plane uh portfolio. We’re going higher, we’re going faster, until we blur the lines between in and out of the atmosphere, and that’s underway right now.”

“I’d say that NASA intends to field an exciting, inspiring, and technologically useful portfolio of X-planes, and I want us to go higher and faster than we’ve ever gone before,” he added during a subsequent question-and-answer session when asked specifically about any plans for a new crewed hypersonic aircraft or a successor to the SR-71. “We’ll see if we can pull anything off in the next handful of years, but, yeah, that is an area of great interest from a developmental perspective.” The SR-71 also came up during a separate panel discussion at the AirVenture show, which included Isaacman.

“What aircraft that you haven’t flown would you like to try?” a member of the audience asked. “SR-71 Blackbird,” Isaacman chimed in first without any hesitation. The other panelists agreed. “Do you have the power to bring that back then, Jared? That’s the next question,” the panel’s moderator added. “That’s classified,” Isaacman responded. The post An SR-71 Blackbird Has Vanished