D-21 Drone--never seen this before

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Well-Known Member
Dec 29, 2003
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I stumbled on to the Squadron SR-71 "In Action" book at work and discovered the D-21 drone. It looks like an SR-71 engine with SR-71 outer wings attached. Looks like it could be carried as a parasite on an A-12 (the CIA SR-71).

I'm thinking an Estes SR-71 kitbash to make a D-21 or even an SR-71/D-21 boost glider combo!

So many ideas, so little time...

The problem they had with the drone was deployment.

Something about releasing another smaller craft from a larger craft that's traveling close to Mach 3.

I guess it's not quite as simple as just flipping a start switch.

That would be quite doable in our scale with a D-21 drone being released as a glider ala Orbital Transport when the parachute pops.

I haven't gone through all the links -

- but I remeber seeing a pic of an SR-71 with what appeared to be a winged, third engine mounted on top of the fuselage between the cockpit and the aft of the plane. I am fairly certain (now) that it was one of these drones mounted on top of the plane.

When I first saw the pic, I thought "are they trying to make the SR-71 faster by supplying it with additional power?"

I get it now......

If one of these drones could be built in modroc scale and made to glide, mounting one on top of an SR-71 model very similar to an Orbital Transport configuration should be a fairly accurate scale representation. Wish I could find that pic I'm referring to....
D-21: A reconnasaince drone which I believe was not powered. AT the end of its mission it dropped a film canister under a parachutre. One of them crashed into the rear cockpit of the SR71.
Originally posted by MetMan

Believe this is the picture to which you refer:


This would be a cool scratch build. Getting that little drone to glide might be a bridge too far, though...


Those aren't the pics I was referring to, but very excellent indeed and showing exactly what I was referring to.

If the drone is built light enough, given a tad of tail weight..... I bet we could figure out a way to make one work!