Dream Chaser Q&A (including suggestions and improvements)

[adrianwyard]

Jim (and anyone else) you previously said DC doesn't have more landing opportunities than the capsules, even though a lifting-body theoretically has more cross-range ability and so shouldn't have to wait as long for the Earth to align in order to get to a given landing site.

Did you mean that the Dragon/CST-100 have more landing opportunities because they can land in any body of water (or flat surface for CST-100) where DC needs a runway?

Or did you really mean capsules can make it to KSC just as quick as DC?

In the case of emergency crew return, you often don't want to land just anywhere. I'm wondering how strong the case is that DC is the best emergency return vehicle.

[Rocket Science]

When you need to set down anywhere of the globe ASAP capsules are fine.

In the immortal words of Mr. Spock, “Crude, but effective.”

[Jim]

Jim (and anyone else) you previously said DC doesn't have more landing opportunities than the capsules, even though a lifting-body theoretically has more cross-range ability and so shouldn't have to wait as long for the Earth to align in order to get to a given landing site.

Did you mean that the Dragon/CST-100 have more landing opportunities because they can land in any body of water (or flat surface for CST-100) where DC needs a runway?

Or did you really mean capsules can make it to KSC just as quick as DC?

In the case of emergency crew return, you often don't want to land just anywhere. I'm wondering how strong the case is that DC is the best emergency return vehicle.

"waiting" for return isn't a discriminator.  Requirement is something like at least one opportunity per day. 

[adrianwyard]

OK, so I think you're saying they all meet the stated requirements, so DC has no competitive advantage.

Would you agree DC could get home faster, even if you don't see that as a valuable capability?

[Lee Jay]

When you need to set down anywhere of the globe ASAP capsules are fine.

As long as you don't mind occasionally landing in the middle of the ocean, on the side of a rocky cliff, or in some other highly-undesirable place that might well get you killed.

[Lee Jay]

Would you agree DC could get home faster, even if you don't see that as a valuable capability?

I would say it's highly valuable in the case of a medical emergency, especially if 4+g's during entry is going to kill whomever is having the medical issue.

[Rocket Science]

When you need to set down anywhere of the globe ASAP capsules are fine.

As long as you don't mind occasionally landing in the middle of the ocean, on the side of a rocky cliff, or in some other highly-undesirable place that might well get you killed.

So long as it’s just occasionally…

DC is my ride of choice…

[Jim]

Would you agree DC could get home faster, even if you don't see that as a valuable capability?

No, because it doesn't exist on earth.  People can be isolated from civilization.   Passengers on cruise ships can not get to a hospital in less than 24 hours.  Why require capability that doesn't always exist on earth.

[adrianwyard]

OK, I understand now. We've been talking about different things. I was assuming your comment on DC's return capabilities vs capsules was based on some aspect of orbital dynamics and/or aerodynamics that I was not familiar with.

[ncb1010]

Passengers on cruise ships can not get to a hospital in less than 24 hours.

Not to nitpick, but cruise ships have their own hospitals, doctors and nurses given that their population is that of a small to medium sized town. For instance, the biggest cruise liner ever built, the MS Allure of the Seas, was designed to support over 6,000 people.

edit: apparently, it supports over 6000 passengers and about 2000 crew.

[Jim]

Passengers on cruise ships can not get to a hospital in less than 24 hours.

Not to nitpick, but cruise ships have their own hospitals, doctors and nurses given that their population is that of a small to medium sized town. For instance, the biggest cruise liner ever built, the MS Allure of the Seas, was designed to support over 6,000 people.

edit: apparently, it supports over 6000 passengers and about 2000 crew.

Yes, I know but people still get medevac off the ships by helicopter when in range of shore.  The ISS can provide medical attention

[aquanaut99]

Yes, I know but people still get medevac off the ships by helicopter when in range of shore.  The ISS can provide medical attention

Sorry, but I got to call incorrect on that, Jim. The ISS cannot provide medical attention that goes beyond treating minor ailments such as cuts and bruises. There is also no true medical professional on board (unlike the cruise liners, which usually have a ship's physician on board). Also, nobody has any experience treating injuries and medical emergencies in zero G. In fact, we don't know if that is even possible (which is, in fact, one of the main arguments against human BEO expeditions: no way to help or evacuate anyone in case of a serious medical emergency).

In case of a serious injury on board ISS, the affected crew member would need prompt evacuation back to Earth. Preferably via a transport system that limits the risk of aditional injury (caused by excessive G's for example).

And no, a seriously injured crewmember on ISS is not the same as a seriously injured person living in an isolated community on Earth. Without wanting to appear disrespective; in the latter case it would hadly make the news. An ISS crewmember injured while working in orbit would, however, be headline news. And if he/she died of her injuries, you can bet the anti-spaceflight people down here would jump into the limelight again and be thankful for the extra ammo they just got in their crusade to bring HSF down...

[Jim]

And no, a seriously injured crewmember on ISS is not the same as a seriously injured person living in an isolated community on Earth. Without wanting to appear disrespective; in the latter case it would hadly make the news. An ISS crewmember injured while working in orbit would, however, be headline news. And if he/she died of her injuries, you can bet the anti-spaceflight people down here would jump into the limelight again and be thankful for the extra ammo they just got in their crusade to bring HSF down...

News has nothing to do with the requirements.

Still doesn't change the requirement of landing within 24hours.

[adrianwyard]

News has nothing to do with the requirements. Still doesn't change the requirement of landing within 24hours.

In a court of law, yes. But if a competitor exceeds the requirements, all other things being equal (e.g. cost) a smart judge will pick that option.

By the way, Blue Origin seem to think the more frequent landing opportunities of their biconic is a good selling point, even though it exceeds requirements: http://spaceref.biz/2012/04/blue-origin-tests-design-of-next-generation-spacecraft.html

Meanwhile you said DC has less usable pressurized volume than the others. That could be a reason DC could lose. Does anyone have reliable figures?

[grr]

Yes, I know but people still get medevac off the ships by helicopter when in range of shore.  The ISS can provide medical attention

Sorry, but I got to call incorrect on that, Jim. The ISS cannot provide medical attention that goes beyond treating minor ailments such as cuts and bruises. There is also no true medical professional on board (unlike the cruise liners, which usually have a ship's physician on board). Also, nobody has any experience treating injuries and medical emergencies in zero G. In fact, we don't know if that is even possible (which is, in fact, one of the main arguments against human BEO expeditions: no way to help or evacuate anyone in case of a serious medical emergency).

In case of a serious injury on board ISS, the affected crew member would need prompt evacuation back to Earth. Preferably via a transport system that limits the risk of aditional injury (caused by excessive G's for example).

And no, a seriously injured crewmember on ISS is not the same as a seriously injured person living in an isolated community on Earth. Without wanting to appear disrespective; in the latter case it would hadly make the news. An ISS crewmember injured while working in orbit would, however, be headline news. And if he/she died of her injuries, you can bet the anti-spaceflight people down here would jump into the limelight again and be thankful for the extra ammo they just got in their crusade to bring HSF down...

I am actually surprised that we have not sent a vet up there along with a small set of mice. Allow the vet to operate on them and see how they recover.

[JonSBerndt]

Wish I could offer more than just this, but SNC issued another press release:
 
Sparks, NV – April 26, 2012 – Sierra Nevada Corporation’s (SNC) Space Systems has signed several Space Act Agreements (SAA) with NASA's Johnson Space Center dating back to May 2011 to assist in both the technical development of, and operations support for, the Dream Chaser® Space System.  SNC has received funding awards from NASA in both rounds of the Commercial Crew Development Program and has chosen to re-invest capital back into the space agency through SAAs with individual Centers, including Houston's Johnson Space Center, to leverage NASA's experience and expertise in human spaceflight.
 
Johnson Space Center's Engineering and Mission Operations Directorates are currently receiving funding from SNC.  These agreements include work in a variety of areas such as thermal protection and the use of the Christopher C. Kraft, Jr. Mission Control Center. Additional SAAs are being developed with several other Directorates within the Center.
 
“Thanks to the work of those at Johnson Space Center, America was able to put men on the moon and the International Space Station into orbit.  As the Dream Chaser® Program develops a vehicle to backfill the capabilities of the Space Shuttle, it will not be without a significant contribution from the experts at Johnson Space Center,” explained Mark Sirangelo, Corporate Vice President of SNC's Space Systems.
 
Several SNC executives will visit the Houston area to participate in the Rotary National Award for Space Achievement (RNASA), where Sirangelo will be the keynote speaker for the prestigious event.   “We are investing in Houston. In 2011, SNC opened its Houston office and continues to create dynamic partnerships with the area's diverse aerospace industry, including the expansion of our investment in the Johnson Space Center,” said Sirangelo.
 
 

[JonSBerndt]

This image was just formally released publicly, but I haven't seen it online anywhere yet.

[Silmfeanor]

This image was just formally released publicly, but I haven't seen it online anywhere yet.

Thanks! it was on L2, although a bit smaller.
Interesting that they're going for the nose-skid. I hope we'll see some sparks and smoke when we get to witness a landing!

[Rocket Science]

Thank Jon,

Anything else you can “squeeze” out of SNC is always greatly appreciated. Keep it coming! 

~Robert

[JonSBerndt]

This image was just formally released publicly, but I haven't seen it online anywhere yet.

Thanks! it was on L2, although a bit smaller.
Interesting that they're going for the nose-skid. I hope we'll see some sparks and smoke when we get to witness a landing!

And I scrunched it down a bit, too. Makes a nice background screen.