Updates Ares Updates and Discussion

Let me add to this business of man-rating and risk managment.

If the history of NASA manned spaceflight accidents is any guide, it would appear that the main risk to space travelers is not how one determines the reliabilty of the hardware or whether the hardware performs as advertised, but rather the managment of NASA.

Both shuttle accidents were caused by known problems which were ignored by naively overconfident managment. Poor systems engineering. The SRBs had engineering limits which were exceeded (low temperature), but they worked fine when you used them properly. The ET had foam-shedding problems from STS-1, which was a violation of requirements that debris not strike the TPS. Good systems engineering means you stop flying until you fix the problem. Bad systems engineering is when you keep flying because you've gotten away with it for a hundred flights and assume it's not a real problem.

Ares I will be under a lot of pressure to get the US back into manned spaceflight with a minimum of funding in a few years, and that pressure is what drives managment to take needless chances.

All rockets have engineering problems, but the risk to crews is not just technical hardware or software issues, it's also operational decisions made under pressure.

---------- Post added at 05:45 PM ---------- Previous post was at 05:38 PM ----------

Yea, sure it was the management failure that ultimately contributed to the destruction of STS-51L, but if the system had been liquid fueled, the management failure might not have happened.

Disagree. You simply cannot engineer your way around bad systems engineering decisonmaking. If LRBs were safer than SRBs, than it would've been something else that eventually would've caused an accident. Or, given the greater perceived safety margin, the decision-makers would've taken even more chances.

Poor design + good systems engineering = slow launch rate and wasted money

(Poor design OR good design) + bad systems engineering = faster launch rate followed by a bad accident.

I am conflating the terms "systems engineering" with "managment", here. Although not exactly the same, systems engineering rigor is the direct responsibility of managment.
 
Yea, sure it was the management failure that ultimately contributed to the destruction of STS-51L, but if the system had been liquid fueled, the management failure might not have happened.

Just by using different technology/o-rings, the management failure might not have happened ;)

If something does happen, people start to think: okay, that's it. We've fixed it and now we know more and are safer. And then you get the next lesson... (STS-107 for example...). Nothing is certain, especially in space flight is anything certain, like Chris Kraft often tends to say (he was an Apollo Mission Control responsible for those who might not know).

Another thing that sets liquid fuels apart from SRBs is that Liquid engines have one area of combustion instead of being a combustion up the entire length of the vehicle. In STS the crew cabin actually sits below part of the combusting part of the engine.

That's exactly why Ares1-X is something totally new, although it still uses a Shuttle SRB.

I personally like the entire design of Ares1 much more than the Shuttle stack, and to be honest, much more than the Saturn1b design. Ares1 has, somehow, a really "cool" look to my taste. And if you look at it standing in the VAB, boy, this beast of a rocket is really huge. I like the idea of a single SRB first stage usage since I was about 15 (no joke). I even did some drawings back then. That was the time when I started to wish that NASA returns to rockets and capsules. You can imagine how excited I was to learn that NASA actually is going to build something I was in favour for years already. A single SRB stage. I still can't believe it. If it'll work, it will be amazing. The criticism will die and you'll read in any dictionary: the biggest and most powerful solid rocket booster:cheers:

And now you know that NASA possibly is managed by little fan boys like me :lol: ;)

---------- Post added at 09:55 PM ---------- Previous post was at 09:48 PM ----------

Ares I will be under a lot of pressure to get the US back into manned spaceflight with a minimum of funding in a few years, and that pressure is what drives managment to take needless chances.

But isn't it usual in case of NASA? I mean, it is hard to tell a NASA rocket/program that did not get under pressure. Especially Apollo and I think STS as well with Skylab in orbit and the gap. Somehow the current events are slightly similar. And there is a chance that NASA abandons a space station a second time to get a new system in orbit "on time" (however you define on time).
 
I personally like the entire design of Ares1 much more than the Shuttle stack, and to be honest, much more than the Saturn1b design.

I too like the Ares I design, however I am holding judgement until after the test in October. As to your comment about the Saturn IB design... I just say that it borders on BLASPHEMOUS!;)
 
Ares I will be under a lot of pressure to get the US back into manned spaceflight with a minimum of funding in a few years, and that pressure is what drives managment to take needless chances.

All rockets have engineering problems, but the risk to crews is not just technical hardware or software issues, it's also operational decisions made under pressure.
And what I fail to understand is that NASA is taking an expensive and potentially hazardous road and attempting to come in under-budget at the same time. This is simply not the time to test a new and potentially dangerous launch configuration.

Frankly, Ares I is completely and utterly unnecessary. There are cheap and reliable launch vehicles already in production which, when man-rated, give NASA everything they really need. Astronauts and the debt-ridden government would both breathe a sigh of relief if NASA had a moment of clarity and sent Orion up on, say, an Atlas V instead of an overly expensive exploding pencil.
 
Yea, sure it was the management failure that ultimately contributed to the destruction of STS-51L, but if the system had been liquid fueled, the management failure might not have happened.
Posted before seeing the new posts EDIT:
Another thing that sets liquid fuels apart from SRBs is that Liquid engines have one area of combustion instead of being a combustion up the entire length of the vehicle. In STS the crew cabin actually sits below part of the combusting part of the engine.
Liquid fueled rockets are just as capable of killing people as solid-fuels.

http://en.wikipedia.org/wiki/Nedelin_catastrophe
 
For those interested, the DM-1 test at the ATK test site in Utah is today. I'll be there in person to watch it, however NASA TV is also going to cover it.

The ground test will be covered live starting around 12:50 p.m. MDT via NASA's education channel at www.nasa.gov/multimedia/nasatv/index.html (click on the "Education Channel" link on the right side of the page. The test is suppose to start at 1:15 p.m.

Keeping my fingers crossed for a good test.
 
Thanks a lot for posting the video.

I indeed missed the words "and lift off" right after "we have ignition":rofl:

I guess I've seen too many Shuttle launches...

Anyway, what a monster of a solid rocket motor. As an astronaut, I would be more scared about ignition rather than about vibrations. It's almost like an explosion.

I think that Ares1 launches will be amazing...
 
When that thing ignited it was like a cannon firing, except that the cannon blast last for two minutes.
 
This video doesn't do justice! This thing was AWESOME! I mean you could feel the Earth move under you feet, the roar, the smoke. MAN what a sight!
 
That's exactly why Ares1-X is something totally new, although it still uses a Shuttle SRB.

Huh? Ares-IX is a PR stunt- it is a shuttle SRB with some ballast and a few sensors strapped on top. If anything "new" is there, it probably wouldn't even make it into the actual Ares-I. ;)

I personally like the entire design of Ares1 much more than the Shuttle stack, and to be honest, much more than the Saturn1b design. Ares1 has, somehow, a really "cool" look to my taste.

"Coolness" to someone's particular "taste" means nothing- I think STS looks awesome, but it's a dangerous, expensive craft.

And Saturn-IB was a really good looking LV... I'm not sure how you could think the unbalanced pencil of Ares-I is better looking...

I like the idea of a single SRB first stage usage since I was about 15 (no joke). I even did some drawings back then.

I also drew pictures of rockets as a kid... one of them had strap-on air lit boosters on the second stage- just because you think something is cool, does not mean it is a good idea.

@Hielor
Liquid fueled rockets are just as capable of killing people as solid-fuels.

While I agree with you on that point, the Challenger and Nedelin disasters were totally different- the corrosive fuels used in the R-16 are not even used anymore (at least not frequently, I may be wrong).

The Challenger disaster was caused by a failure of the SRB o-ring, but only because the operators neglected safety warnings, and pushed the machinary too far.

I'd be wary of solid fuel rockets though, and liquids have several advantages...
 
@Hielor


While I agree with you on that point, the Challenger and Nedelin disasters were totally different- the corrosive fuels used in the R-16 are not even used anymore (at least not frequently, I may be wrong).

The Challenger disaster was caused by a failure of the SRB o-ring, but only because the operators neglected safety warnings, and pushed the machinary too far.

I'd be wary of solid fuel rockets though, and liquids have several advantages...
To be fair, the Challenger failure mode of the SRB wouldn't even come close to that catastrophic of an event on an Ares.
 
To be fair, the Challenger failure mode of the SRB wouldn't even come close to that catastrophic of an event on an Ares.

At least with the ARES they have an LES. As a point of clarification here, even though the SRB was the initial source of the Challenger disaster, it was the aerodynamic forces that caused the break up. If you remember right, both SRB survived the break up until they were detonated remotely.
 
Huh? Ares-IX is a PR stunt

Ares-IX is a test flight to gether data for validating models, which has an impact on future test flights and the final Ares1 design.

- it is a shuttle SRB with some ballast and a few sensors strapped on top. If anything "new" is there, it probably wouldn't even make it into the actual Ares-I. ;)

Ares-IX is a new launch vehicle. A single SRB never has been used as a first stage on such a configuration.

And Saturn-IB was a really good looking LV... I'm not sure how you could think the unbalanced pencil of Ares-I is better looking...

Soyuz for example does not look less like a pencil at all after first stage separation. What I like on the Ares1 design is its clarity and simplicity. And because it uses flight proven hardware in a new and safer configuration than STS does.

I also drew pictures of rockets as a kid... one of them had strap-on air lit boosters on the second stage- just because you think something is cool, does not mean it is a good idea.

The solid rocket first stage is that much of a good idea that NASA is seriously going to use it.

I'd be wary of solid fuel rockets though, and liquids have several advantages...

For solids there is no need for elaborate fuel storage and fueling mechanisms at the launch pad. The fuel also does not need to be elaborately kept at a certain temperature. On the whole solids consist of less elaborate, sensitive and less high-maintenance propulsion technology.

If handled properly, solids in fact turn out to be more reliable than liquids (and less prone to delays, if any, like STS). The Shuttle SRB's are absolutely reliable for decades. In case the Ares1 first stage prove oneself, that manned launch vehicle is going to be the most less complex one and most safe one NASA has ever operated. Imagine the STS-51L booster as the Ares1 booster. Probably nothing would have happened. Even after the ET broke up, those two boosters continued to do what they are supposed to do as if nothing happened. I think that the Ares1 first stage is a very wise and reliable design and decision.
 
Last edited:
Back
Top