Based on the NASA Space Shuttle C concept 'Deep Bay'

[McColm]

I've been having a few problems with the cargo-shuttle but after reading what Mossie posted and a rummage in the 'don't throw that away as I might need it someday ' box I found what I was looking for the spare 1/144 Revell Discovery Space Shuttle,  this had been stripped for parts and partially built for another build for this GB but I cancelled it.
 The cargo hold is a lot deeper and with dry testing now that the wings are back on the lower part is a better fit on the launch pad. I'm still going to reinforce this to take the extra weight after PSR on the 'Deep Bay Cargo Shuttle '.

[Weaver]

So what happened to the cargo pod after it had delivered its load?

It was relatively cheap to build and used engines that had been used several times and were no longer rated for manned flights so it was allowed to burn up on the way down.
That was the RW concepts at the time. Feel free to back story anything you like.

Thanks mate.  Seems like a waste of materials.

It does, and always did to me as well, but you have to remember that you are talking about a 60's mindset in the "richest country in the world". Over here at that time any recycling was done by your local "Steptoe & Son" or 3d on the return of a pop bottle.

The economics of reusability as they apply to spaceflight can be surprising and counter-intuitive. If you're not very careful, the cost of recovering and refurbishing the space vehicle can become more than the cost of a new one, and you end up spending more money instead of saving it. Ships, people and refurbishment factories are expensive to buy, run and have sat around doing nothing, and as Kerick pointed out, the service life of things like rocket engines is much lower than we're used to for jets. You might end up recovering a set of engines that you're not allowed to use again anyway.

ESA got into precisely this spiral with Ariane 6 recently. They studied all sorts of exotic methods for recoving some or all of it. In one version, the engine section detached, re-entered, then flew back to base using folding wings and a pair of turbo-props with folding propellor blades...

However the catch-22 was this: Ariane's launch cadence is so low that their engine/booster factory is already working at the slowest possible rate it can do. If they started recovering and reusing engines and boosters, then the factory would be sitting idle for much of the time, but they'd still have to pay all the overheads and wages for it. It would only be worthwhile if they could increase the cadence to the point where the recovered engines and boosters were satisfying the increade demand, in addition to the new-builds from the factory. However, Ariane has a very particular and well-defined niche in the launch industry, and there is basically no chance of this: the payloads just aren't there.

Rocket Labs in New Zealand got into a similar spiral with their Electron rocket: they were looking at catching the first stage in mid-air with a helicopter as it fell under parachutes, but they gave up on it because the recovery cost didn't justify the launch savings. They're now looking at a fully-recoverable rocket called Neutron (it'll have nose doors just like the SPECTRE rocket in You Only Live Twice!) which will land like SpaceX's boosters, but how the payload economics will work out I don't know.

This launch cadence issue is what nobody pays attention to when looking at SpaceX's reusability: it isn't just the impressive technology that makes it work physically, it's the fact they're launching lots and lots of rockets that makes it viable financially. Even then, it's worth remembering that they gave up on the original plan to recover second stages (too fast and far downrange for the recovery hardware to justify it's mass and cost) and fairings (not worth the effort).

[McColm]

Not glued together, but a dry test to see what it looks like with all the other pieces.