Should NASA use the Delta IV for an Orion Ascent Abort Test?

[fredinno]

Why not use the Delta IV Medium (5m Upper stage, 2 SRBs) for an Orion Ascent Ascent Abort Test?

Currently, a separate Orion Abort Test Booster is intended to test the use of the Orion Launch Escape System- a SRB Single-Stage rocket that will only be used once. Though based off the Peacekeeper missile 1st stage, it will still require lots of money to develop.

It would be probably be cheaper to use a Delta IV to do this same job (saving costs- Falcon 9 and Atlas V would require developing a new adaptor to do this job). A 5 m diameter upper stage and 2 SRBs would be used to prevent the need for a special adaptor- and to better simulate the launch conditions. As Orion is heavy, the upper stage (not really needed, this is a suborbital launch Abort test) would be empty of fuel.

So should this be done? It looks like a Delta IV is a better way to test the Orion's Abort System during flight than a newly designed SRB. Or am I missing something?

[Temstar]

I recall there were some pretty good reasons why Little Joe II was developed, which is analogous to what's happening here. They needed a high degree of versatility of thrust, and normal liquid fuel engines (at the time at least) didn't have deep throttling capability. Little Joe II could achieve this by changing the number of sustainer engines and their ripple fire pattern to simulate different stages of the Saturn V ascent.

Given you will probably want to fire a few of these abort test boosters to test abort of different flight stages it's probably cheaper to make this single stage solid rather than buying five Delta IV.

[fredinno]

59 minutes ago, Temstar said:

I recall there were some pretty good reasons why Little Joe II was developed, which is analogous to what's happening here. They needed a high degree of versatility of thrust, and normal liquid fuel engines (at the time at least) didn't have deep throttling capability. Little Joe II could achieve this by changing the number of sustainer engines and their ripple fire pattern to simulate different stages of the Saturn V ascent.

Given you will probably want to fire a few of these abort test boosters to test abort of different flight stages it's probably cheaper to make this single stage solid rather than buying five Delta IV.

Actually, last time I checked, there's only one test planned- a high-altitude test of an Orion abort on the SLS with the SRBs burning. Also, Delta IV can throttle.

[Hannu2]

I think that SRB is so much cheaper than Delta that it is no problem to make adapter. I am also sure that somebody have thought changes in Nasa. Even if it is not true there may be complex political reasons and restrictions in Nasa's decisions. Nasa uses several times more money to achieve things than for example private companies but it is government's way to support to US aerospace companies.

[fredinno]

7 minutes ago, Hannu2 said:

I think that SRB is so much cheaper than Delta that it is no problem to make adapter. I am also sure that somebody have thought changes in Nasa. Even if it is not true there may be complex political reasons and restrictions in Nasa's decisions. Nasa uses several times more money to achieve things than for example private companies but it is government's way to support to US aerospace companies.

Developing an entirely new SRB is more expensive than a Delta IV, especially when it uses a new 5m diameter.

Also,you are leaving the scope of this thread.

[Nibb31]

A Delta IV costs over $200 million. A refurbed Peacekeeper is likely pocket change. I don't think they'll be spending more than the cost of a Delta IV on an adapter.

Edited February 12, 2016 by Nibb31

[Hannu2]

13 minutes ago, fredinno said:

Developing an entirely new SRB is more expensive than a Delta IV, especially when it uses a new 5m diameter.

Also,you are leaving the scope of this thread.

I do not think so if they use an old missile. SRB does not have to be 5 m. Only simple (compared to spacecrafts) adapter is needed.

You limit this discussion too tight. Certainly nobody here knows exact costs of options. If somebody knows he is not allowed to tell. We can only guess costs and reasons of decisions without knowing many things which are very important for Nasa.

[fredinno]

9 hours ago, Nibb31 said:

A Delta IV costs over $200 million. A refurbed Peacekeeper is likely pocket change. I don't think they'll be spending more than the cost of a Delta IV on an adapter.

No, it's more of an entirely new SRB. http://zzakkslab.blogspot.ca/2009/07/orion-abort-test-booster-almost.html

And YES, it is 5m diameter.

[DerekL1963]

7 minutes ago, fredinno said:

No, it's more of an entirely new SRB. http://zzakkslab.blogspot.ca/2009/07/orion-abort-test-booster-almost.html

From your own link:  "Motive power is going to come from surplus Peacekeeper ICBM 1st stage motors."   Peacekeeper motors aren't new, not by a long shot.

8 minutes ago, fredinno said:

And YES, it is 5m diameter.

No, Peacekeeper motors aren't 5m in diameter.

It's as Nibb and Hannu2 say - an relatively cheap refurbished motor in a fairly cheap adapter.  No doubt much cheaper than a Delta IV.

Not to mention the tests are taking place at White Sands, where there is neither a Delta IV launch pad nor the infrastructure for handling the amount of cryogenics a Delta IV requires.   (Which is the real answer as to why they're developing a new launcher at modest cost.)

[fredinno]

12 minutes ago, DerekL1963 said:

From your own link:  "Motive power is going to come from surplus Peacekeeper ICBM 1st stage motors."   Peacekeeper motors aren't new, not by a long shot.

No, Peacekeeper motors aren't 5m in diameter.

It's as Nibb and Hannu2 say - an relatively cheap refurbished motor in a fairly cheap adapter.  No doubt much cheaper than a Delta IV.

Not to mention the tests are taking place at White Sands, where there is neither a Delta IV launch pad nor the infrastructure for handling the amount of cryogenics a Delta IV requires.   (Which is the real answer as to why they're developing a new launcher at modest cost.)

Oh, ok. Now I understand. Sorry.