antovolk wrote:TV Spot 13 (German):

Does anyone know the song in this amazing tv spot?!

Technical questions about the Rangers and Landers in these clips & trailers, for anyone who might shed some light. (Maybe stoifics42)

Is a Ranger supposed to be single-stage-to-orbit vehicle? Then why does it need to be on a big booster rocket in one of the shots? Does it use conventional rocket propulsion? Then how is it fueled? Where is the reaction mass?

Or do they land, never to return to space? That doesn't square with some of the clips, either. Problematic.

Also the Lander. What kind of propulsion? And a ridiculous shape for aerodynamics. How does it shed orbital kinetic energy, i.e., heat?

I don't think the answers (if anyone has them) would be spoilers. But of course I may be mistaken.

VitaminQ wrote:Technical questions about the Rangers and Landers in these clips & trailers, for anyone who might shed some light. (Maybe stoifics42)

Is a Ranger supposed to be single-stage-to-orbit vehicle? Then why does it need to be on a big booster rocket in one of the shots? Does it use conventional rocket propulsion? Then how is it fueled? Where is the reaction mass?

Or do they land, never to return to space? That doesn't square with some of the clips, either. Problematic.

Also the Lander. What kind of propulsion? And a ridiculous shape for aerodynamics. How does it shed orbital kinetic energy, i.e., heat?

I don't think the answers (if anyone has them) would be spoilers. But of course I may be mistaken.

I'll take a shot at this. For reference, here's a gallery of all useful Ranger/Lander screencaps I have as of now: http://imgur.com/a/Cp6FZ

Both the Ranger and the Lander seem to be SSTOs, otherwise they'd be fairly useless out in the field. The Rangers are initially sent up to Endurance atop what looks to be a modified Saturn V (you can see this in one of the patch templates: http://i.imgur.com/cFwu5ma.png). I'm not entirely sure why the Rangers don't just fly up on their own power, but if they really are being flown up using a Saturn V first & second stage then that leaves extra room in the third stage to bring up some other stuff, like fuel or food or whatnot. During Apollo the third stage performed the lunar injection burn; that'd be unnecessary in this scenario, thus freeing up the fuel tank volume for cargo space.

The only engine that comes close to making sense for the Ranger would be some variant of SABRE (http://www.youtube.com/watch?v=wg2T7MUULZQ), which is a dual-mode engine that can use either onboard liquid O2 or compressed atmospheric O2 as its oxidizer to react with onboard liquid hydrogen. It would be air-breathing while in atmosphere, then switch to rocket mode at some altitude. Even with SABRE, however, the Ranger seems unrealistically small & roomy for its job as a SSTO. There's barely any room left for fuel tanks once you hollow out the crew area. Another glaring problem is how it's a VTOL when there's no prominent thrust outlets on the underbelly.

The Lander's even more mysterious given that we don't see it nearly as much in the trailers. As you've pointed out she's not aerodynamic at all. As for surviving reentry, you'd have to cover half the exposed skin in some kind of high-strength heat tiling, and that's a severe mass penalty for something as oddly shaped as the Lander. Not to mention the fact that some of the windows would be exposed - speaking of which, the window configuration on both ships seems really odd and unnecessarily complicated.

I've actually had a pet theory as to the Lander's main function for a while now. It's been said in interviews that it acts somewhat like a "heavy-lift helicopter" and is responsible for moving Endurance's colonization kit modules to the surface of a habitable planet. If you look closely in several screencaps, you'll see the bottoms of those modules are covered in thick black plating, and their tops seem to roughly match the shape of the Ranger's underbelly. I'm betting that when a colonization module disconnects from Endurance, the Lander then mates with the top of the module. The whole assembly reenters the atmosphere, the module's bottom acting as a blunt ablative heat shield. The Lander's four primary VTOL engines would stick out the sides, and would then gently set the module down on the surface Curiosity-skycrane-style. This would partly explain her odd shape and why the VTOL engines are so much more prominent than her rear engines. Basic diagram of this whole process:



From a hard technical standpoint, the Ranger & Lander have a ton of problems, but I'm willing to let it slide given the effort that's been put into realism elsewhere in the movie. At least they look the part - their overall aesthetic seems very NASA-inspired.

geozou1 wrote:

antovolk wrote:TV Spot 13 (German):

Does anyone know the song in this amazing tv spot?!

+1

geozou1 wrote:

antovolk wrote:TV Spot 13 (German):

Does anyone know the song in this amazing tv spot?!

I'm dying to find out as well.

It doesn't look like this has been posted yet. Couple new shots/angles.

International TV Spot #1:

Gotta love that new angle.

stoifics42- thanks much for your well thought-out answers. Very interesting about the Lander procedure and probably spot-on. The similarity to the Curiosity system is obvious now that you point it out.

"...the Ranger seems unrealistically small & roomy for its job as a SSTO. There's barely any room left for fuel tanks once you hollow out the crew area. Another glaring problem is how it's a VTOL when there's no prominent thrust outlets on the underbelly."

Yes. Those are exactly my main problems with the Ranger.

"Not to mention the fact that some of the windows would be exposed - speaking of which, the window configuration on both ships seems really odd and unnecessarily complicated."

Yep. And the shot of McConaughey jumping out the Lander door as it hovers(!) *really* bothers me. I don't think you'd want to be anywhere near the business end of conventional rocket engines holding up that much mass. Oh well.

Bottom line, though- my hat's off to Nolan, for taking on the hard science, bringing back the "sense of wonder" to SF film, and promoting manned space exploration. As for folks well-grounded in physics like yourself and me (I'm an EE)- well, we just have to work a little harder suspending our disbelief, don't we?

What number is the Survive TV spot? Is that one new?