SSTO Testing

[TMac3000]

Okay, so assuming we build a single-stage-to-orbit craft like the DG, what would be the logical order of steps for flight testing it? (aside from the first atmospheric tests to determine if the thing can fly at all)

 

[garyw]

If such a thing was to be built it would go through thousands of tests before the first components were to be cast. A lot of computer simulation testing and wind tunnel style testing as a well as scale model testing.

Once the first prototype rolls off the production line they should already have a fair chunk of tests done.

 

[ikrase]

Yeah, today it's almost all math and computers.

And component testing.

And possibly models launched on booster for suborbital re-entry tests?

Air drop tests?

Then subsonic, then supersonic, then hypersonic and finally suborbital flight tests.

 

[RisingFury]

The thing would definitelly fly. The big question would be how close to the expected was the performance...

 

[Arrowstar]

The thing would definitelly fly. The big question would be how close to the expected was the performance...

It also depends on how wide you cast your net when you define 'fly'.

And since we're talking about testing, don't forget all the structural test articles, the boilerplate models, engine testing, integration testing, thermal balance, thermal control...

 

[TMac3000]

It also depends on how wide you cast your net when you define 'fly'.

By 'fly', I meant taking off and buzzing around the field to see how it handles in the air at 'ordinary' altitudes (less than 50,000 feet) and subsonic speeds.

And since we're talking about testing, don't forget all the structural test articles, the boilerplate models, engine testing, integration testing, thermal balance, thermal control...

Got it. The reason I asked is because, being the realism freak that I am, I'm doing flight tests of the Delta Glider IV, pretending it just rolled off the line. So far I've done a "regular" flight test (just doing circles around the field), a cross-range test, a heat-shield test, and today I did the first sub-orbital hop, reaching an altitude of 104 kilometers before coming back down to land at the Cape.

 

[Ark]

We do it like NASA: Put a couple guys in the seat, point it skyward, and go.

 

[Andy44]

We do it like NASA: Put a couple guys in the seat, point it skyward, and go.

Exactly what I was thinking. The space shuttle orbiter was never tested at hypersonic speeds, or even transonic speeds, so the very first time it went that fast, it had two guys riding it through the atmosphere at mach 25!

The only real tests at hypersonic speeds at that point had been with various lifting body shapes, not many winged vehicles, aside from the straight-winged X-15, which was a totally different shape from the STS orbiter.

They designed the thing on paper, did some wind tunnel tests and some computer modeling on mainframes. Nothing like we have today. And they decided it would work.

And they were right. And a little lucky.

 

[Ark]

Well, they did glide test it, but that's all they could feasibly test without a full launch. Given the expense of building the orbiters, they couldn't even do an unmanned orbital test.

Sometimes circumstances dictate that you predict to the best of your ability, and just give it your best shot.

The DGIV or XR2 could do various incremental tests before full orbital, though. The Shuttle had to launch as a complete orbit-capable stack, a horizontal takeoff/landing SSTO spaceplane could just shut the engines down without reaching orbital speed.

 

[Andy44]

They could have built a sub-scale glider with the orbiter's double-delta shape and launched it on an Atlas into a hypersonic test, but as far as I know they didn't. That wouldn't have cost too much, and it was done many times with various "shapes" in the 60s.

 

[RisingFury]

By 'fly', I meant taking off and buzzing around the field to see how it handles in the air at 'ordinary' altitudes (less than 50,000 feet) and subsonic speeds.

When we're dealing with orbital winged craft, the handling at supersonic speeds is generally more interesting...

Got it. The reason I asked is because, being the realism freak that I am, I'm doing flight tests of the Delta Glider IV, pretending it just rolled off the line. So far I've done a "regular" flight test (just doing circles around the field), a cross-range test, a heat-shield test, and today I did the first sub-orbital hop, reaching an altitude of 104 kilometers before coming back down to land at the Cape.

Might wanna add a launch abort test. Launch like you do when launching to orbit, then when you're at a significant altitude, try to return to Cape without the help of engines...

 

[TMac3000]

I will take that under advisement. Thanks!

 

[Travis Reed]

Well, they did glide test it, but that's all they could feasibly test without a full launch. Given the expense of building the orbiters, they couldn't even do an unmanned orbital test.

And yet, somehow, the Soviets managed to do exactly that with their shuttle... AFAIK there were no major problems during the test. Buran even landed itself...where they wanted it to... If the Russian space program hadn't lost its funding, it's quite likely that they'd have actually used it instead if scrapping parts and letting others rust away.

 

[Wally]

Well, they did glide test it, but that's all they could feasibly test without a full launch. Given the expense of building the orbiters, they couldn't even do an unmanned orbital test.

The Russians did. Buran lifted, circled the Earth two times and landed precisely and safely on the pre-determined runway, completely automatic. With the same vehicle that was planned to do manned missions. Too bad it never did, though.