Stratolaunch: General Company and Development Updates and Discussions

[Markstark]

I think the renderings look awesome. Also, we know Paul Allen has serious money. So they’re in better shape than a lot of the other new companies developing small sat launchers. I guess this is a different weight class though. Wish they posted payload capacity to other orbits.

[nacnud]

6 tons to LEO? Should be enough to throw a light all-electric comsat (Boeing 702SP etc) to GTO, assuming a decent upper stage, right? Otherwise I don't see where the market comes from in just LEO.

Constellation deployment.

Constellation replenishment. BFR, New Glen/Armstrong, will put up the constellation. This will replace that failed sat in a weird orbit at very short notice.

[Coastal Ron]

I think all of these options look really interesting. Not sure there is a market for them, but hey, if you have the money you can take your time finding a market.

I will note though that currently the Stratolaunch is a single-point-of-failure (SPOF) transportation system, meaning that until they build a second aircraft I doubt anyone is going to tie the success of their business to the availability of the Stratolaunch vehicle. And that is just the nature of the beast when you only have one vehicle that can perform your main service.

I mention that because I would not be surprised if they are already planning for a second aircraft, after they have had time to test out the first one. Plenty more 747's being retired, so still lots of used parts they can get for a fraction of what the new ones cost. 

[TripleSeven]

I think all of these options look really interesting. Not sure there is a market for them, but hey, if you have the money you can take your time finding a market.

I will note though that currently the Stratolaunch is a single-point-of-failure (SPOF) transportation system, meaning that until they build a second aircraft I doubt anyone is going to tie the success of their business to the availability of the Stratolaunch vehicle. And that is just the nature of the beast when you only have one vehicle that can perform your main service.

I mention that because I would not be surprised if they are already planning for a second aircraft, after they have had time to test out the first one. Plenty more 747's being retired, so still lots of used parts they can get for a fraction of what the new ones cost. 

the brightest lights in "this" administration is the SecDEF and the USAF Secretary...they both have a plan for this airplane

[niwax]

Anyone have an idea what these stages are going to cost? The upper stages for reusable rockets are growing a lot the smaller the push from the first stage gets. The F9 first stage only saves 3000-4000m/s when expendable rockets stage at more like 5000-6000m/s. I doubt this arrangement saves more than 8000m/s. So these stages are ridiculously large for medium lift upper stages. How much money does using the plane actually save over a more conventional rocket?
The heavy variant can't be that far from being able to launch from land with a small stretch. The difference is only propellant, and that plane isn't exactly sipping fuel. You're expending three engines and tanks either way.

[CameronD]

I think all of these options look really interesting. Not sure there is a market for them, but hey, if you have the money you can take your time finding a market.

I will note though that currently the Stratolaunch is a single-point-of-failure (SPOF) transportation system, meaning that until they build a second aircraft I doubt anyone is going to tie the success of their business to the availability of the Stratolaunch vehicle. And that is just the nature of the beast when you only have one vehicle that can perform your main service.

I mention that because I would not be surprised if they are already planning for a second aircraft, after they have had time to test out the first one. Plenty more 747's being retired, so still lots of used parts they can get for a fraction of what the new ones cost. 

A second one??  They haven't got this one (literally) off the ground yet.

As I see it (cynic that I am) the parallels with Spruce Goose are extraordinary...

[Lars-J]

Anyone have an idea what these stages are going to cost? The upper stages for reusable rockets are growing a lot the smaller the push from the first stage gets. The F9 first stage only saves 3000-4000m/s when expendable rockets stage at more like 5000-6000m/s. I doubt this arrangement saves more than 8000m/s. So these stages are ridiculously large for medium lift upper stages. How much money does using the plane actually save over a more conventional rocket?
The heavy variant can't be that far from being able to launch from land with a small stretch. The difference is only propellant, and that plane isn't exactly sipping fuel. You're expending three engines and tanks either way.

A triple core only does 6 mt to LEO? That's not great. And it won't be cheap either. To quote Lando Calrissian:
"This Deal Is Getting Worse All The Time"

I'm excited to see this thing fly, but I don't give great odds on any of these three variants/payloads ever flying.

[yg1968]

According to their website, the Medium Launch Vehicle is already in development. The other two are under study.

[Prettz]

According to their website, the Medium Launch Vehicle is already in development. The other two are under study.

Are there any indications how long it's been under development (i.e. how far along they might be)? That's gotta be one of the questions on everyone's minds.

[docmordrid]

According to their website, the Medium Launch Vehicle is already in development. The other two are under study.

Are there any indications how long it's been under development (i.e. how far along they might be)? That's gotta be one of the questions on everyone's minds.

Well, Jeff Thornburg joined them in June 2017 after a stint at SpaceX as Principal Propulsion Engineer for Raptor Engine Development and Senior Director of Propulsion Engineering. Before that he worked as J-2X Turbomachinery Lead Engineer. Whatever engine(s) they're working on could be interesting.

[ThePhugoid]

6 tons to LEO? Should be enough to throw a light all-electric comsat (Boeing 702SP etc) to GTO, assuming a decent upper stage, right? Otherwise I don't see where the market comes from in just LEO.

Constellation deployment.

Constellation replenishment. BFR, New Glen/Armstrong, will put up the constellation. This will replace that failed sat in a weird orbit at very short notice.

No, deployment.  A large constellation made up of 6 ton satellites wouldn't make financial sense.  Constellations will be made of smaller satellites (not thinking only Starlink here) and big rockets don't always make sense as sole deployers because they can't hit several orbital planes, and they can't manifest their full load given that lack of access.  Medium class launch in this 6k and below class make better deployers, although that may or may not work out given their cost.  Only time will tell that part.

[GWH]

The 3 tonne launcher is really similar in capacity or more capable than PSLV, Anagara 1.2, Rockot, Dnepr, Soyuz 2-1v, Vega, Minotaur C, Delta II 7320, and Firefly's proposed Alpha and Beta tri core (there is a little overlap here between 1 and 3 tonne).

The the 6 tonne variant compares similarly to the retired Delta II 7920, but falls shy of Soyuz 2-1b.

It is fascinating to see all the new launchers looking to carve out there own niche in terms of payload capacity and price. For the most part there isn't much overlap, aside from the existing launchers listed above.
That will also make for some dilemnas, any small constellation providers will have the option of choosing between multiple dedicated launches or comanifested om medium vehicles, too large a constellation and they push to heavy lift.
Taking a guess, if the single core is as advertised at $30Million that the tricore ends up around $45M. 

[dwheeler]

Official images and information available on their relaunched website, includes plan view renderings (attached).
http://www.stratolaunch.com/how-we-launch/

<snip>

Space Plane

<snip>

Just eyeballing the space plane it looks like it would need a booster stage or at least some additional fuel capacity, no?

[Zed_Noir]

<snip>
Just eyeballing the space plane it looks like it would need a booster stage or at least some additional fuel capacity, no?

In theory you can have wing tanks for kerosene during ascent.

It depends on how much of the airframe is tankage for propellants. Maybe X-15 style drop tanks if additional propellants is needed.

[ThePhugoid]

<snip>
Just eyeballing the space plane it looks like it would need a booster stage or at least some additional fuel capacity, no?

In theory you can have wing tanks for kerosene during ascent.

It depends on how much of the airframe is tankage for propellants. Maybe X-15 style drop tanks if additional propellants is needed.

Doubt these are kerosene, given the scale of the vehicles plus the supposed goal of SSTO for the winged booster.  They are most likely hydrogen.

[Lars-J]

<snip>
Just eyeballing the space plane it looks like it would need a booster stage or at least some additional fuel capacity, no?

In theory you can have wing tanks for kerosene during ascent.

It depends on how much of the airframe is tankage for propellants. Maybe X-15 style drop tanks if additional propellants is needed.

Doubt these are kerosene, given the scale of the vehicles plus the supposed goal of SSTO for the winged booster.  They are most likely hydrogen.

There are other options than kerosene and hydrogen, you might have heard of some upcoming rockets featuring methane. Methane does really seem to be the right choice (IMO) for a space plane.

[docmordrid]

>
There are other options than kerosene and hydrogen, you might have heard of some upcoming rockets featuring methane. Methane does really seem to be the right choice (IMO) for a space plane.

Teslarati has a rear view concept of Kraken firing, and that plume is rather bluish.

https://www.teslarati.com/ex-spacex-engineer-air-launched-rockets-largest-aircraft/

[Archibald]

Whatever the propellant combination, the huge issue with SSTO (and air launch makes too little a difference) is propellant mass fraction. Hydrolox: 92%, storable, methane, or kerosene + LOX = 95% or more.

Now with Thrust Augmented Nozzle, things might be different... it really get the best of LH2 and kerosene with LOX, with stellar results.
Melvin Bulman from Aerojet, Paul Allen has a job  for you !!! 

[envy887]

Whatever the propellant combination, the huge issue with SSTO (and air launch makes too little a difference) is propellant mass fraction. Hydrolox: 92%, storable, methane, or kerosene + LOX = 95% or more.

Now with Thrust Augmented Nozzle, things might be different... it really get the best of LH2 and kerosene with LOX, with stellar results.
Melvin Bulman from Aerojet, Paul Allen has a job  for you !!!

Air launch actually makes enough of a difference for a spaceplane to get to LEO: reduced gravity and drag losses, and the ~300 m/s velocity boost reduce the needed delta-v to around 8500 m/s. And the much thinner atmosphere means a higher expansion ratio can be used, increasing the average ISP. A methane vehicle would need about a 91% propellant fraction, while a hydrogen one would be closer to 85%. I think those are feasible.

A methane single-stage vehicle that maxes out the carrier aircraft's 225 tonne liftoff limit would only put about 4 tonnes of payload in orbit, even with some generous assumptions about dry mass. A hydrogen vehicle of the same starting wet mass should orbit closer to 10 tonnes of payload.

Since Stratolaunch is only advertising 3 and 6 tonnes to LEO for the medium and tri-core versions, I suspect they are planning on a hydrocarbon or even a storable propellant. The space-plane is referred to as "medium-class payload" on their website, which would imply the 3-4 tonnes LEO payload of a methalox vehicle.

[francesco nicoli]

I am sure someone already asked it, but I wonder: can DreamChaser launch from Stratolaunch?