Why did the Constellation program go over budget while the SLS is still on budget?

[ScallopPotato]

Even the Altair lander had some technical problems. For one, it was way too big. That was because its lower stage was designed to do both the Lunar Orbit Insertion burn (for the Altair and Orion together) and the actual landing on the Moon. That resulted in too much delta-v needed on a single stage, which made it considerably overweight. The large mass of the Altair was one of the reasons the Ares V design had to be upgraded to carry 180 tons to LEO, which resulted in even more cost and schedule slips. The Constellation program had to have 2 launches with together almost twice the mass to LEO of a Saturn V, for a single Moon landing which had only a bit higher capability than the Apollo landings.

We do need funding for a lander or deep-space habitat so the SLS can start doing some interesting missions, but it shouldn't be the Altair. There's some designs for a reusable lander which could go from a L1 station to the Moon's surface and back up which is looking promising, much smaller than the Altair.

Even I know to have my TLI/Capture/Descent stages separate because efficiency.

Where can I find those reusable designs?

[Moar Boosters]

Orion was (and still is) overweight because it isn't just a LEO taxi. Its requirements were (and still are) to be capable of keeping 4 people alive for 21 days, performing contingency EVA, and reentering from a lunar trajectory. Soyuz can't do any of that, and neither can Dragon, CST-100, or DreamChaser. In the days of Constellation, it also had to land on solid ground with airbags and be reusable.

Ares-I would probably have been capable of launching a Block-1 LEO version of Orion, which had a cut-down SM. It was underpowered for launching the full-blown lunar Orion.

That was my point. All Ares-1 would have been suitable for was a LEO taxi, but they tried to apply it to something more than it should have been too early. It was supposed to be a quick and easy project using the remains of the shuttle program, but the only way that would have worked is if they had a suitable payload to match the first rocket they built.

[Kryten]

But for an LEO taxi, Atlas V would do, so it would still make no real sense. Atlas is already most of the way to being crew-rated with far less money than was put into Ares-1.

[Nibb31]

And in the end, Atlas V is being man-rated now for DreamChaser and CST-100, and it will be used to launch Orion unmanned for EFT-1.

[bigdad84]

For one, it was way too big. That was because its lower stage was designed to do both the Lunar Orbit Insertion burn (for the Altair and Orion together) and the actual landing on the Moon. That resulted in too much delta-v needed on a single stage, which made it considerably overweight.

The reasoning for the Altair doing the Lunar Orbit Insertion burn was for future plans. After a base was implemented on the Moon, the Altair would make delivery of cargo without an Orion craft tagging along. So it needed to be able to brake into orbit on it own.

[ScallopPotato]

But for an LEO taxi, Atlas V would do, so it would still make no real sense. Atlas is already most of the way to being crew-rated with far less money than was put into Ares-1.

Yeah, but supposedly Ares I was going to be safer than the Altas V. Of course, vibrations don't seem that safe.

I think it's funny how the Ares-I and Ares-V basically follow the meme of "moar struts" and "moar boosters" because of design flaws.

[TerLoki]

One thing that always bugged me about the shuttle, SLS, Ares V, and, the biggest offender, the Ares I was that they're mixing solid fuel rockets and manned vehicles together. Yes, NASA has them pretty darn reliable these days and at least they're sticking with the proven modular SRBs from the shuttle, but if it were me I'd feel a little iffy about being sent up to orbit on top of a rocket that can't be shut down.

Even the Altair lander had some technical problems. For one, it was way too big. That was because its lower stage was designed to do both the Lunar Orbit Insertion burn (for the Altair and Orion together) and the actual landing on the Moon. That resulted in too much delta-v needed on a single stage, which made it considerably overweight. The large mass of the Altair was one of the reasons the Ares V design had to be upgraded to carry 180 tons to LEO, which resulted in even more cost and schedule slips. The Constellation program had to have 2 launches with together almost twice the mass to LEO of a Saturn V, for a single Moon landing which had only a bit higher capability than the Apollo landings.

We do need funding for a lander or deep-space habitat so the SLS can start doing some interesting missions, but it shouldn't be the Altair. There's some designs for a reusable lander which could go from a L1 station to the Moon's surface and back up which is looking promising, much smaller than the Altair.

Honestly it might be a good idea to just dust off and upgrade the Apollo LM if that's the case about Altair, after all if it's not broken don't try to fix it (just look at Soyuz).

I hadn't heard of the L1 station concept before, but I can certainly believe it as a promising proposal. I built the same thing in career mode around the Mun and Minmus, just in low orbit, and it works like a charm for biome-hopping.

[Kryten]

Yes, NASA has them pretty darn reliable these days and at least they're sticking with the proven modular SRBs from the shuttle, but if it were me I'd feel a little iffy about being sent up to orbit on top of a rocket that can't be shut down.

Solids can be shut down just fine, with blowout panels. They just can't be shut down and restarted, but neither can most liquid rockets.

[Tommygun]

Solids can be shut down just fine, with blowout panels. They just can't be shut down and restarted, but neither can most liquid rockets.

I'm curious now, have any test been done with these blowout panels at high speeds?

I'd be worried about tumbling.

[Moar Boosters]

But for an LEO taxi, Atlas V would do, so it would still make no real sense. Atlas is already most of the way to being crew-rated with far less money than was put into Ares-1.

Much of the reason the program was cancelled was because it didn't really show any results early on. Sure the Atlas could be improved to make it man-rated, but it's a dead-end rocket compared to the Ares-1. The biggest proposed Atlas lifts 30t to orbit, where as the biggest proposed Ares would have lifted about 190t.

I just think if they'd shown more results earlier on, the program might well have not been cancelled. They could have used the proven 4 segment booster to create a LEO taxi which is much cheaper to run than the shuttle, which would have likely increased their chance of further funding for the giant Ares-5.

Now it seems they've gone in the complete opposite direction. They're building a giant rocket in the SLS which they don't have any solid mission plans for. It seems NASA are figuring if they can get one flying quickly enough, there's no way congress will ignore it, and they'll get their funding for new missions.

[Nibb31]

Much of the reason the program was cancelled was because it didn't really show any results early on. Sure the Atlas could be improved to make it man-rated, but it's a dead-end rocket compared to the Ares-1. The biggest proposed Atlas lifts 30t to orbit, where as the biggest proposed Ares would have lifted about 190t.

Apples and oranges. Ares-V was to always fly unmanned. Orion was only to fly on Ares-I. Separation of crew and cargo makes sense.

The reason to build Ares-I instead of going with Atlas V was to make Ares-V economically viable by sharing common components that you launch more frequently. Namely, this was beneficial for ATK-Thiokol which did some huge lobbying behind the scenes. Remove Ares-I and Ares-V was no longer viable (just like SLS is not viable).

I just think if they'd shown more results earlier on, the program might well have not been cancelled. They could have used the proven 4 segment booster to create a LEO taxi which is much cheaper to run than the shuttle, which would have likely increased their chance of further funding for the giant Ares-5.

The 4-segment booster wasn't powerful enough to put a LEO taxi Orion on orbit, which is why they opted for a 5-segment booster. By this time, the development cost of the whole new SRB, plus the J2X upper stage, plus all the dampening and vibration mitigation effort, made the whole thing way more expensive than man-rating the Atlas V or Delta IV. It was obvious that the program was going to be cancelled.

Edited April 1, 2014 by Nibb31

[Kryten]

Again, the 5-segment SRB was not new. It was a resurrected part of a pre-Columbia upgrade program, one was tested all the way back in 2003.

- - - Updated - - -

Much of the reason the program was cancelled was because it didn't really show any results early on. Sure the Atlas could be improved to make it man-rated, but it's a dead-end rocket compared to the Ares-1. The biggest proposed Atlas lifts 30t to orbit, where as the biggest proposed Ares would have lifted about 190t.

Ares I and Ares V were pretty much completely unrelated.

[metaphor]

Even I know to have my TLI/Capture/Descent stages separate because efficiency.

Where can I find those reusable designs?

I can't find the powerpoint right now, but it was something like this design.

[rdfox]

I'm curious now, have any test been done with these blowout panels at high speeds?

I'd be worried about tumbling.

A bit late, but these have been tested on every single launch of the Minuteman ICBM (i.e., all the development and testing flights, the launches used to provide ICBM RV targets for BMD tests, and at least one qualification test per year where a randomly selected missile is pulled from its silo, taken to Vandenberg, and launched down the Pacific Missile Range to Kwajelein for a full-range test flight with inert warheads--now usually combined with BMD test launches to save money).

NASA was considering them for the Shuttle's SRBs, but they were cancelled partly to reduce weight, but mostly to reduce cost by eliminating the engineering needed for them.

[Francesco]

And in the end, Atlas V is being man-rated now for DreamChaser and CST-100, and it will be used to launch Orion unmanned for EFT-1.

Wait, isn't it Delta IV Heavy for EFT-1?

On the same note, I don't understand what was the purpose of Ares I at all, since it was supposed to put the same weight of a Delta Heavy to LEO.

Why not just build Ares V/SLS for large unmanned payloads, and then launch the crew on existing Delta Heavy's?

[sojourner]

Wait, isn't it Delta IV Heavy for EFT-1?

EFT-1 is unmanned, but yes, last I heard it was going up on a Delta-IV Heavy.