Author Topic: ULA Vulcan Rocket Q&A with ULA's Dr. George Sowers - April 14, 2015  (Read 63251 times)

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
Dear Dr. Sowers,

Is ULA considering the use of propellant densification via subcooling of the Vulcan first stage propellants as a way of increasing the performance of the vehicle?

All the best, Steven.

yes

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
Dr. Sowers, congratulations on the Vulcan reveal!

Of the components and technologies announced and/or discussed today, which one most excites you personally, and why?

Tough choice, but I pick IVF.  IVF is almost magical in the utilization of what would otherwise be waste (boiloff, heat from the ICE, etc) to provide the essential functions of the stage (power, pressurization, RCS).  It is the key to long duration and reuse through refueling.

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
Dr Sowers, thank you for taking the time and trouble to answer questions.

How long have you been working on the Vulcan concept and what approximate stage in development have ULA reached? (eg PDR, CDR etc)

We've been working on many of the pieces for years.  For example, plans for ACES predate ULA.  As a system, we just completed Vulcan step 1 SRR.  PDR by year end.

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
Another vote of thanks for agreeing to take questions, Dr. Sowers!

ULA surely did trades on full first stage recovery versus engine compartment midair... why is midair recovery so compelling, compared to the path SpaceX is on, which seems to offer the promise of far greater cost reductions?

I've promised to post a simple spreadsheet that will give some insight into the economics (probably next week).  But the gist goes like this:  We are recovering >60% of the cost of the booster for 1/6th of the performance loss (5% vs 30%) in a manner that completely shields the hardware from the harsh reentry environment.

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
Dr. Sowers

AFAIK the current ULA launchers were only used to launch NASA or USAF payloads.
Does ULA plan to (re-)enter the market of commercial comsat launches with Vulcan?

Spacediver

Yes.  BTW, we never completely left the commercial market.  For example, we are launching Mexsat later this year on Atlas.

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
Dr. Sowers,

     If ULA is planning to attempt either full stage or Engine and Avionincs package recovery, whatis the particular method that you have in mind for such recovery?  Powered descent to land, Parachute to sea, or a combination of these strategies?

We plan to start with engine recovery and see where that leads. 

OK, I think I'm caught up. Thanks for the great questions.  If Chris allows, I'd be happy to take follow up questions. The space symposium is wrapping up today with a farewell snowstorm.

Offline DanielW

  • Full Member
  • ****
  • Posts: 437
  • L-22
  • Liked: 295
  • Likes Given: 60

Another vote of thanks for agreeing to take questions, Dr. Sowers!

ULA surely did trades on full first stage recovery versus engine compartment midair... why is midair recovery so compelling, compared to the path SpaceX is on, which seems to offer the promise of far greater cost reductions?

I've promised to post a simple spreadsheet that will give some insight into the economics (probably next week).  But the gist goes like this:  We are recovering >60% of the cost of the booster for 1/6th of the performance loss (5% vs 30%) in a manner that completely shields the hardware from the harsh reentry environment.

Dr. Sowers I would like to reiterate the thanks everyone else have given for this opportunity. I look forward to your success in a big way.

I am curious though. How the extra performance gets monetized? It seems like the 1/6th number will rarely be realized since there will always be some mismatch of payload to capability. The shielded environment does seem like a good way to make recertification cheaper though.

Offline tmoesser

  • Member
  • Posts: 7
  • Journeyman rocket scientist
  • Northern Utah
  • Liked: 7
  • Likes Given: 7
Dr. Sowers,
Thank you for taking questions on this exciting vehicle!  I hope you are able to answer mine.  My question is performance and possibly strategy related, so I understand if you can't answer it.  (It looks like three questions, but it's really one with multiple approaches.)

With Delta II soon to retire, Delta IV-M to go next, and Atlas V 401 also being phased out, how does Vulcan fit in with the Small- to Medium-class launch capability and market?  The Vulcan core booster seems oversized for those classes of missions, and oversized usually means overly expensive.  Will a Vulcan 401 be a reasonable replacement for the most frequently-flown vehicle configurations in your fleet, and if so, how or why?  Related, after the introduction of ACES in ~2023, will Centaur continue to fly to serve the Medium market?

Thank you in advance, and enjoy the heavy snow that we're sending your way (that is, drive home safely!).
« Last Edit: 04/16/2015 05:13 PM by tmoesser »

Offline DatUser14

  • Full Member
  • ****
  • Posts: 457
  • Liked: 94
  • Likes Given: 135
Dr Sowers, thanks for doing this Q&A. My question is this; during the development of Vulcan, was varying the amount of BE-4's for the first stage (more or less) considered?
Where can I apply for SpaceX fanboy?.

Offline Malderi

  • Member
  • Full Member
  • ****
  • Posts: 529
  • Liked: 53
  • Likes Given: 50
Dr Sowers,

If follow-up questions are allowed (thanks for answering my first one!), can you talk about other items in the trade space that were examined but maybe rejected? I'm sure you looked at full-stage reuse, multiple engines, that sort of thing, but anything more fanciful like 4+ core vehicles, flyback/flythrough boosters, SSTO etc? Not sure how much you can talk about it, but your title *is* Chief Mad Scientist, so hopefully there's some real mad science stuff that you can talk about. I totally understand if none of that can be public until much later when a history of the development program can be written.

Thank you again!

Offline Space Ghost 1962

  • Senior Member
  • *****
  • Posts: 2276
  • Whatcha gonna do when the Ghost zaps you?
  • Liked: 2031
  • Likes Given: 1495
Thank you for answering my earlier question Dr. Sowers.

You've talked about reusing an upper stage. After payload separation, you've got a free US - to reuse it would need to acquire orbit for new payload, prox ops, attach, execute a series of timed burns, and separate again.

ACES/Centaur don't appear to be anything more than typical, autonomous US at the moment. Even Agena, which was more of a spacecraft than just an US, didn't have all of that to do the above. Nor are payloads attached to US without significant ground prep, spin table, etc. Had not heard Astrotech making on-orbit house calls yet ;)

Where's the extra SC part coming from that can "command" / "manage" / "handle" ACES/Centaur?

Again, thank you from the NSF community here. We really appreciate it when you communicate with us like this.
« Last Edit: 04/16/2015 07:55 PM by Space Ghost 1962 »

Offline Martin FL

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 2218
  • Liked: 49
  • Likes Given: 129
I'll avoid a Reddit-style question about if you prefer cakes or pies, and ask evolvability. Just how much can you upgrade this specific system by way of upmass, and where do you think is the top line for upmass? (say versus mulitple launches) in the future customer requirement market.

Offline sanman

  • Senior Member
  • *****
  • Posts: 3591
  • Liked: 417
  • Likes Given: 1
Hi Dr Sowers,

Regarding aerocapture of the parachuting engine by helicopter, will it necessarily be a manned helicopter, or is there a possibility of an unmanned drone helicopter being used to reduce risk?

Thanks for your time, sir.

Offline TrevorMonty

Thanks Dr Sowers for all the great answers.

Could the SMART system be applied to upper stage? Tory hinted at using it elsewhere.

Online MATTBLAK

  • Elite Veteran & 'J.A.F.A'
  • Senior Member
  • *****
  • Posts: 3674
  • 'Space Cadets' Let us; UNITE!! (crickets chirping)
  • New Zealand
  • Liked: 671
  • Likes Given: 1236
Dr Sowers; you mentioned earlier in the thread that you would not rule out a future 'triple core' heavy version of Vulcan. Has ULA also looked at versions with 8 or even 10x solid boosters on a single corestage? It appears that many boosters might fit on a 5 meter stage. It would seem to me that such a launcher with an ACES upper stage would have a lot of capability!!
"Those who can't, Blog".   'Space Cadets' of the World - Let us UNITE!! (crickets chirping)

Offline gin455res

  • Full Member
  • ***
  • Posts: 314
  • bristol, uk
  • Liked: 7
  • Likes Given: 18
Dr Sowers,

When eliminating turbine based units from the IVF system design, were sub-atmospheric 'inverted brayton cycles' such as outlined in the linked pdf, considered.  This is a scheme for a residential scale CHP (high enthalpy) micro-turbine system, that reverses compressor and turbine sequence to  produce very-low-power turbo-generators.

Or would continuous combustion require too high a fuel flow to keep combustion temperatures sensible, (what is the peak combustion temperature in the IC engine anyway)?

http://www.agileturbine.com/publications/Small%20Scale%20Combined%20Heat%20and%20Power.pdf 

thanks
Toby

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
Dr. Sowers -
What drove the decision to select an as-yet unbuilt and untested engine from a new player in the aerospace world (BE-4 from B.O.)? If ULA were selecting an existing engine with flight heritage (RS-68 for example) it would provide an obvious schedule acceleration benefit. But when considering a new American built engine, especially in the non traditional methalox category, for vertical integration reasons it would seem to make sense for ULA to develop its own.

Removing my second question per request from mods.
Did ULA consider using SpaceX engines on its rockets? Raptor will be methalox, and in the right thrust regime for a 2-engine Vulcan first stage. Is this even a feasible business move?

The business case was the main driver.  We looked very hard at all the options including RS-68/DIV.  Blue may not be well known, but they are credible, competent and 3 years into the development of BE-4.

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
Dr. Sowers,

I would like to ask question related to solid boosters:

Shall Vulcan be human rated in configuration with multiple solid boosters, i.e. capable of capable of launching orion?

Edit: reduced to one question.

Thank you in advance!

Vulcan will be human rated.  Once ACES comes on line, Vulcan will be more capable than DIV heavy

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
Hi Dr. Sowers,

ULA has a long history of successful missions, SpaceX is an emerging business, and Blue Origin an enigma. Overall, it seems that everyone is losing the PR war with the general public -most people just don't care. A number of space enthusiasts are excited for SpaceX's entry into the market, simply because of their grander stated ambitions (realistic or not).

How can/will ULA help reinvigorate the public's appetite for spaceflight?

Thanks!
VulcanCafe
(excellent rocket name choice!)

Wow! tough question that requires an essay, if not a dissertation to do justice.  A couple of thoughts to get you started.

Public engagement with the overall space enterprise has traditionally be the role of national space agencies or even heads of state (remember Kennedy's speech).  And that requires a vision that everyone buys into.  Sadly lacking at the moment.  Some of the planetary missions excepted.

Public engagement with private companies is generally through products and services. Unfortunately, the consumer interface with space products is pretty far removed.  GPS is an example.

Public engagement will increase when the nation gets a unified and inspirational vision for publicly funded exploration and/or when commercial space starts affecting the daily lives of consumers.

I hope ULA can play a role in both arenas by making access to space more affordable and delivering new capabilities to open up BEO.

What are your ideas?

Offline georgesowers

  • Full Member
  • **
  • Posts: 204
  • Liked: 381
  • Likes Given: 0
There was a mention of selecting the AR1 engine in 18 months if the Blue Origin engine isn't coming along as expected.  What impact would that have on first stage design?  Thanks!

Since AR-1 uses RP fuel, the first stage design would look a lot like Atlas V.

Tags: