Most excellent X-37B pix!

[n810]

I don't think those are concrete. I bet they are some sort of foam. If the hydraulics did fail, concrete would do some serious damage to the thermal protection.

[vipers7]

I think the blocks could be a result of the blown tyre during landing.
Maybe someone does not want to take chances and prevent stress on the landing gear.

X-37B test mission called big accomplishment - Air Force News | News from Afghanistan & Iraq - Air Force Times

[Paper Kosmonaut]

Not concrete? Still it looks very improvised and crude. Surely they must have some special kart for the plane they can roll under the fuselage and lift it up? This looks almost like a Russian approach (and that doesn't have to be bad at all but is unusual to see out of Russia..)

[Texman]

Well, for crash recovery of aircraft with collapsed gear, they use a combination of a large crane and inflatable bags, so it's not inconceivable they used some form of foam padding. The airframe is not that heavy, notice the men lifting on the wings.

[Zathros]

So you can move the plane around easily, it can be supported by Styrofoam blocks.. A couple of guys can move it around? Sounds like a pretty successful spaceship. I wish I had one. This being an experimental flight, I wouldn't be surprized that the weight was taken off the landing gear so it could be studied. We did some simple things with the Sikorsky ABC ( Advancing Blade Concept) and the RSRA, that still cannot be divulged, but sometimes, simplicity is the name of the game.

[Retired_for_now]

OK - poll time. One rocket engine or two?

Les's linked pix seem to show only one rocket engine vs. the two in the engineering docs. But, that engine is off-center ... what the heck? Photo editted for some reason; really one (off-center) rocket; something else going on; ...

Yogi (like to get at least one part of this model right)

[Paper Kosmonaut]

I'm tempted to say one asymmetrical placed engine nozzle.
As it is for braking in a space environment, does it matter it is not centered? Perhaps there's some equipment behind tha aft bulkhead that prevents the nozzle being placed dead center. The pics don't really look edited or censored. It is not too off-center to not be a single engine and I can't see why they want us to believe it has an off-center engine if it wasn't the truth.
The Mercury capsule had three separately firing brake engines on the retropack that pointed in three different directions. Perhaps the X37b is manoeuvred in an attitude that compensates for the off-center engine? Interesting issue, isn't it?

[Retired_for_now]

PK - agree with your note, why would they alter anything or remove one engine after landing? Rocket engines are placed (or paired symmetrically) so they are aligned with the spacecraft's center of mass. Otherwise the craft spins when the engine is fired. The Mercury retro pack used a trio of rockets each aimed at the spacecraft centerline - like the legs of a camera tripod - so you get a nice, straight thrust with all three firing. If all three didn't fire together you'd get a really wild ride (tumble and spin cycle).
If the X-37 has a single, off-center nozzle it must be aimed slightly to one side so its axis goes through the spacecraft's center of mass, which seems odd.
And on another note - after a closer look at the launch pictures and reading the blogs of the more technically adept it seems the X-37 stack used the short, 68 foot payload fairing. Fortunately that just means one less stacked cylinder in the build up and move some graphics around; nose remains the same (and the same "how do you build it in halves" problem).
Yogi

[Paper Kosmonaut]

The retro's on the Mercury fired in a sequence, 5 seconds apart. One was enough for returning into the atmosphere but they fired all three of them. Each retrograde rocket fired for ten seconds. So they were not all simultaneously firing. That would have meant the capsule might have been spinning or tumbling as you said. Anyway, you're of course right about the axis and the "tripod" of rocket fire it gives.

That still doesn't explain the off-center nozzle of the X-37b. The perspective of the best pics should have shown another nozzle at least. But its position is, looking at the visible nozzle, a bit doubtful. Could the two engine nozzles be placed so close together? On NASASpaceflight they also discuss it but they to do not come with a clear answer.

[Retired_for_now]

PK - I'll defer to you on the Mercury details. Sequentially firing the rockets must mean the axis of each rocket was aimed at the capsule's center of mass (I'll grant you the facts but am holding firm on the physics ...).
Guess I'll continue trolling for a consensus on X-37 - at least until Les finds more pictures.
Yogi