What is the aeroplane in the first image?

I noticed this photo in a youtube clip, and at first glance thought it was a three-engine Blackbird SR-71, but it appears to be a single-seater.

enter image description here

The text and audio does not reveal what the photo is of.


Some googling suggests that is a D-21 drone atop a M-21, and wikipedia has this somewhat-unhelpful photo.


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    $\begingroup$ That photo is from the Boeing Museum of Flight, in Seattle, WA. Detailed description here: museumofflight.org/Exhibits/blackbird $\endgroup$ – abelenky Oct 21 '18 at 18:09
  • $\begingroup$ @abelenky Nice find - thank you. Shows a more useful photo, $\endgroup$ – Criggie Oct 21 '18 at 20:26
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    $\begingroup$ The aircraft in the video is an M-21 and is actually a two place aircraft. One Pilot and one Launch Control Officer. $\endgroup$ – Mike Sowsun Oct 21 '18 at 21:30
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    $\begingroup$ indeed. The rear windows are visible, albeit difficult to see due to the quality of the image. $\endgroup$ – jwenting Oct 22 '18 at 4:47

The large aircraft is the Lockheed M-21 (which was developed from the Lockheed A-12, the same aircraft that the SR-71 was developed from), and the smaller aircraft is the D-21 drone.

The wikipedia article on the D-21 has a lot of information.

  • $\begingroup$ Deep Space thanks. Apparently some editor has taken a rather amoeboid response to my answer. FYI the MD remark was humor! $\endgroup$ – Robert DiGiovanni Oct 21 '18 at 20:13

It’s called an M-21 Blackbird. It’s a derivative of the A-12/SR-71 family of aircraft modified for launching a supersonic ramjet powered reconnaissance drone called the D-21 (“M” designation standing for “Mothership” and “D” standing for “Daughtership”). The program never worked out and destroyed one aircraft which the drone collided with during separation and launch tests. The D-21 drones made several more flights, albeit by launching from a B-52 bomber using a rocket booster to accelerate it to Mach 3, but all but one flight failed, either crashing over enemy territory or sinking in the ocean either due to vehicle or telemetry failure. The last known M-21 Blackbird is on display at Seattle’s Museum of Flight at KBFI.


I thought it was the McDonnel-Douglas SST prototype, but no, this is essentially an SR-71/A-12 carrying a drone on top.

There were issues with this design as the drone, when being launched from the "mother ship" at supersonic speeds, would be struck by the shock waves and become uncontrollable dangerously close to the tail, resulting in a risk of collision. Other carrier aircraft, such as the B-52, were more successful launch platforms.

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    $\begingroup$ No, it is not an SR-71. $\endgroup$ – abelenky Oct 21 '18 at 18:08
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    $\begingroup$ Excuse me, the Carrier aircraft is of the A12/SR-71 type. Please do some checking. The drone on top is actually the "daughter". Forgiveness, this is more than 50 years ago for the newbies. $\endgroup$ – Robert DiGiovanni Oct 21 '18 at 19:43
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    $\begingroup$ It is an M-21, which is not an A-12 or SR-71. Just because the planes look similar on a superficial level does not mean they are the same. $\endgroup$ – abelenky Oct 21 '18 at 20:34
  • $\begingroup$ A bit more than superficial resemblance here, but I'll go with the above answers. 60 years hence, can they make the M-21 itself a drone, and not bother "launching" anything from it? And I will keep it as an SST candidate, shutting down the mains and cruising on the center at altitude. Whatever is was, it did not work, but remains an interesting piece of history. $\endgroup$ – Robert DiGiovanni Oct 22 '18 at 0:45

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