Stratolaunch

[Mat Parry]

No idea...

They're going to have to find something for it to do, because launching 3 Pegasus rockets at once is a ludicrous proposition (and a very unconvincing cover story for secret military space applications). With only ~5 Pegasus launches in the last decade, the demand is small.

It would seem to me that, rather than a guiding conspiracy, a series of events (largely involving the supplier of the proposed rocket boosters) have cascaded down to result in a dubious business model.

Then again, who knows...

1. All of a sudden the Chinese appear to want their own massive/impractical 6 engined beast (Antonov An-225 Mriya). Did something spook them into playing catch up off the shelf.

Or maybe

2. Northrop caught wind of a flourishing future market in secret rocket boosters for the military via stratolaunch and this contributed to their decision to buy orbital ATK.... if only we knew someone who knew about Northrop Grumman corporate strategy

Please note, I'm joking about Northrop Grumman's acquisition of Orbital ATK.

 

[blackstar]

No idea...

They're going to have to find something for it to do, because launching 3 Pegasus rockets at once is a ludicrous proposition (and a very unconvincing cover story for secret military space applications). With only ~5 Pegasus launches in the last decade, the demand is small.

It would seem to me that, rather than a guiding conspiracy, a series of events (largely involving the supplier of the proposed rocket boosters) have cascaded down to result in a dubious business model.

This is easy to understand if you look at it through the lens of a billionaire's ego:

-other billionaires had their own rockets
-he wanted his own rocket
-he also wanted it to be more spectacular than theirs
-so he dictated that it be launched from the world's largest aircraft

The end result is that the "solution" did not really have a market it was going to serve, and no way to serve an existing market more economically. But the rich guy still wants his big airplane.

 

[Mat Parry]

I think you're right.

I must admit I don't often pull the "billionaire ego lens" out of storage to look through! I guess Elon Musk has got me accustomed to thinking all billionaires are like Tony Stark, when infact some are more like.... well a bit orange coloured and far too fond of twitter.

 

[sferrin]

Apparently they've started taxiing the beast.

 

[Archibald]

It will be an awesome flying machine, one can't deny that fact. Except it will be quite expensive and unuseful. But hell, Allen has a crapload of money, if he wants to sink it, his own business.

I wonder if it will go to Le Bourget Airshow someday. Albeit Le Bourget might be too small for such a beast.

 

[fredymac]

Stratolaunch is basically a hobby for Paul Allen who has an estimated net worth of around $20 Billion. I figure it is a more productive use of money versus a castle on a mountain top and has a more plausible chance of eventual profitability than a lot of the mega infrastructure/real estate projects I see around the world.

https://www.youtube.com/watch?v=2zmmapVbATI

 

[steelpillow]

I wonder how many MOABs you could hang under its wing and still fly the round trip over North Korea?

 

[Archibald]

250 metric tons. A MOAB weight 10 tons. So that's 25 MOABs.

 

[steelpillow]

250 metric tons. A MOAB weight 10 tons. So that's 25 MOABs.

My, there was me imagining a handful at best. You wouldn't need nukes with a Mother of All Bombers like that!

 

[Archibald]

You wouldn't need nukes with a Mother of All Bombers like that!

That's an understatement ! ;D

 

[bobbymike]

http://spacenews.com/pentagon-budget-funds-small-launch-services-to-gain-greater-access-to-space/

The Air Force creating a budget line for small launch is a “very good thing for the industry,” said Steve Nixon, vice president of strategic development at Stratolaunch.

Stratolaunch is developing the world’s largest aircraft platform and plans to launch Orbital ATK’s Pegasus vehicles into space for the first time in 2018, Nixon told SpaceNews. He said the services his company would offer fit the type of missions that the military is talking about, “Particularly the idea of having a resilient launch capability that could provide access to space in a contested environment.”

 

[Flyaway]

Just released new aerial and ground shots of the latest test series performed this weekend. More to come! stratolaunch.com/gallery.html

https://twitter.com/stratolaunch/status/968215041278291968

 

[sferrin]

Can't wait to see it fly. (Hopefully more than once.)

 

[Archibald]

I'm confident there will be no accident. It's serious engineering. What is really not serious is the usefulness of that big thing... such a big aircraft to launch little Pegasus rockets. Just because nobody wanted to create a rocket to be launched from the aircraft. That's a little pathetic when you think about it.
Meh.
Then again, it's Paul Allen money, not mine. Plus one can't deny it's a beautiful aircraft, and quite impressive with that. I do hope it will fly to Le Bourget airshow someday.

 

[sferrin]

I'm confident there will be no accident. It's serious engineering. What is really not serious is the usefulness of that big thing... such a big aircraft to launch little Pegasus rockets. Just because nobody wanted to create a rocket to be launched from the aircraft. That's a little pathetic when you think about it.
Meh.
Then again, it's Paul Allen money, not mine. Plus one can't deny it's a beautiful aircraft, and quite impressive with that. I do hope it will fly to Le Bourget airshow someday.

Yeah, it's a shame nobody has wanted to spend the money for a decent sized launcher for the thing. Maybe they could use it as a test bed, like the B-52 at Edwards (or wherever that thing is based).

 

[GeorgeA]

It was always intended to have a big (~500K lb) launch vehicle to deploy. The economics of that haven't panned out, it appears.

 

[sferrin]

It was always intended to have a big (~500K lb) launch vehicle to deploy. The economics of that haven't panned out, it appears.

Right. Nobody wanted to pony up the money for the launcher, a launcher that would probably be over-priced if it's launch aircraft were for some reason unavailable.

 

[Archibald]

The problem is that the aircraft, while giganormous, can't lift more than 250 mt of rocket. 250 mt is too light and small a rocket to compete with anything - Proton, F9R, Ariane 5 weights hundreds of tons, but that's what is needed to lift the huge GEO comsats... to GEO. Stratolaunch can't launch any meaningful payload to GEO, and that's the big problem.

As for LEO mega-constellations, it brings no credible advantage over, for example, Rocketlab Electron. Or F9R. Or even a freakkin' Soyuz.

The math was against them from day one. IMHO of course.

Then again, Paul Allen has plenty enough of dozens of billion of dollars to allow himself to be *wasteful* in such ventures.

 

[steelpillow]

Maybe they can sling a huge cargo pod under there and compete with the An-225 Mriya in the heavy haulage sector.

 

[martinbayer]

The rocket propelled Interim Hotol reusable spaceplane concept, see http://www.astronautix.com/i/interimhotol.html, had a gross mass of 250 metric tons and was designed to be launched from an An-225...

Martin

 

[sferrin]

Maybe they can sling a huge cargo pod under there and compete with the An-225 Mriya in the heavy haulage sector.

But how many runways are wide enough for the landing gear?

 

[Flyaway]

Why is Paul Allen building the world’s largest airplane? Perhaps to launch a space shuttle called Black Ice.

But Allen has even bigger ambitions for Stratolaunch and is considering pairing it with a new space shuttle that’s known inside the company as Black Ice.

The Black Ice space plane — should it be built — would be about as big as the former space shuttle developed by NASA and capable of staying up for at least three days. It could be launched from virtually anywhere in the world, as long as the runway could accommodate Stratolaunch’s size. And it would be capable of flying to the International Space Station, taking satellites and experiments to orbit, and maybe one day even people — though there are no plans for that in the near-term.

Then it would land back on the runway, ready to fly again.

https://www.washingtonpost.com/news/the-switch/wp/2018/03/06/why-is-paul-allen-building-the-worlds-largest-airplane-perhaps-to-launch-a-space-shuttle-called-black-ice/?utm_term=.978390de27c8

 

[Flyaway]

Stratolaunch planning first aircraft flight this summer

Stratolaunch expects to conduct the first flight of its giant aircraft this summer as it develops a broad spectrum of launch services that will make use of it, the company said April 16.

Stratolaunch has performed two taxi tests of the aircraft at the Mojave Air and Space Port in California so far, most recently in late February. Three more taxi tests of the vehicle are planned according to company officials, speaking on background during the 34th Space Symposium here.

Those taxi tests will take place at progressively higher speeds. During the most recent test, the plane reached speeds of up to 74 kilometers per hour. The next test will reach speeds of nearly 130 kilometers per hour, with later tests going up to 220 kilometers per hour.

http://spacenews.com/stratolaunch-planning-first-aircraft-flight-this-summer/

 

[Archibald]

http://spacenews.com/stratolaunch-planning-first-aircraft-flight-this-summer/

https://www.youtube.com/watch?v=SSbBvKaM6sk

Whooooooooooooohooooooooo !!! I want to see that thing flying, even if it is mostly a pointless vanity project.

 

[TomcatViP]

However, the company is making clear it has other uses for that aircraft than launching the Pegasus.

Someone should put them in contact with the Belgian air force... Just in case they are forced to keep soldiering with their F-16 any longer.

 

[Michel Van]

Hell yeah i wanna see the Stratolaunch take off fly around airfield and lands, with Blur Song 2 as soundtrack on Youtube

Someone should put them in contact with the Belgian air force... Just in case they are forced to keep soldiering with their F-16 any longer.

ROFL

 

[Flyaway]

Stratolaunch has confirmed what most people have long speculated: it’s developing its own launch vehicles for its air-launch system, including a reusable space plane that could eventually carry people.

https://twitter.com/jeff_foust/status/1031549089828286464

In-depth Wired piece about the background of Stratolaunch.

https://www.wired.com/story/stratolaunch-airplane-burt-rutan-paul-allen/

 

[Archibald]

Not much new information bar the Roc origins (the cockpit was to be on the tail ? WTH ? it would like a giant Pond Racer ! )

With or without air launch, if that Black Ice is to be a SSTO, then the propellant mass fraction remain as tricky as in the day of the Venture Star.
If LOX/LH2, 92% of the SSTO drop mass (not launch mass !) shall be propellants. If not LH2, then it is 95%.

Starting from the Roc payload of 250 metric tons, either it mass less 21 metric tons or less, with empty tanks, otherwise it never goes into orbit. As simple as that ! Those 21 tons shall include a) the propellant tanks around the propellants b) the airframe around the tanks and c) whatever payload can be shoehorned into such a vehicle.

Air launch provides merely shaves 1 km/s of delta-v out of the 10 km/s. 10% ain't much, and what worse, the rocket equation has a logarithm stuck inside it, so it is even less than that.

Then again, maybe this time it will work. For the record, Musk BFS, even with the big BFR under it (hence a TSTO) will have a SSTO-like prop mass fraction because it needs it to go from LEO to lunar surface and back with a decent payload. On paper at least. So let's see what Musk do with BFS.

A mini--BFS air dropped from the Roc would be quite a sight !

 

[fredymac]

Given the size of the motherplane, the shuttle will be big and apparently unmanned.

 

[steelpillow]

No reusable space plane can make it as a single-stage payload from a subsonic launcher. The energy saving over a ground launch is not as big as most people think. As a minimum it would require a suborbital second stage of some description, be it Shuttle-style external tank, Virgin-style spaceplane or plain old-fashioned Pegasus-style rocket stage. The rockets in the graphic might be good for varying payload sizes, with each step larger representing lower cost, but the orbital spaceplane depicted is just fantasy art.

 

[Flyaway]

Bit more info here.

Finally, the biggest airplane in the world has some rockets to launch

https://arstechnica.com/science/2018/08/stratolaunch-announces-not-one-but-an-entire-fleet-of-rockets/

 

[blackstar]

No reusable space plane can make it as a single-stage payload from a subsonic launcher. The energy saving over a ground launch is not as big as most people think.

Yeah, there's a reason that during the entire history of the space age there have been few attempts at air launch, and nothing really commercially successful. Pegasus is the only one that has stuck around, and its launch rate is so low that it's hard to believe it makes any money--imagine the cost simply to keep that L1011 certified year-round--and has probably been kept going just so Orbital could keep its foot in the door. (The guy who created Pegasus has written and spoken at lectures and been very blunt about how it has not worked out. In nearly 30 years it has launched as many payloads as they originally planned to launch within the first couple of years of service.)

It's not just physics that work against this, however. Launch sites also support launch vehicle and payload preparation. They have facilities (equipment) and people. If you launch from a plane, you're still going to need fixed facilities for rocket and payload processing. You're going to encapsulate your spacecraft in a clean room, and keep it powered and cooled. And you're going to need reliable equipment and facilities to do that. Range support has gotten a lot more flexible, which helps air launch. But another thing hurting Stratolaunch is that the plane is so big that it is going to be limited from where it can operate. It's not like they're going to fly that out of any airport with a long runway.

So it then comes back to the question of why anybody would want to do this? What's the advantage? They're not going to stage the plane from many places, and how far is it going to fly from its staging airfield to launch a rocket? What does that give you that you cannot already get from a fixed location? And with SpaceX able to launch bigger rockets for less money, is it possible to simply get what you need by using a bigger rocket than you normally would?

 

[fredymac]

Paul Allen is 65 years old so he probably still has most of his brainpower intact. Someone convinced him to spend big money to find out if air launching can become a winning launch business. Of course, a person who knows software can also be a fool as well. Luckily, the bill to determine which it is will be his alone and the rest of us can sit back and enjoy the spectacle.

 

[steelpillow]

So it then comes back to the question of why anybody would want to do this?

Quite a few reasons, really.

Cryogenic liquid fuel boiloff is one reason. Approx 10% of any LOX/LH2 fuel load will boil off during the initial stages of launch and its tankage is just dead weight. A mothership can keep it topped up, allowing the later-stage tanks to be 10% smaller. That allows a significantly bigger payload and/or higher orbit.

Operational flexibility is another. You can fly round inconvenient weather patterns to find an open window, not have to wait for it to come to you. You can fly to an optimal launch spot and add a few mph in the optimal direction: different orbits are best reached in different ways and you are not tied to one spaceport's way. You can resupply and relaunch quickly, reducing the number of launchers needed to support a busy schedule.

Economy of operation is yet a third. Several of those flexibility options also offer significant cost savings and/or heavier payloads. More significantly, if you have a delicate payload such as space tourists, your gee force is severely limited and a rocket must waste an age hanging in the sky burning gargantuan amounts of fuel. Substituting aerodynamic lift for the thirstiest flight segment offers equally gargantuan cost savings. It's not so important if you can pile on those gees for a robust payload, a rocket first stage then makes a lot more sense.

Pegasus is a commercial failure largely because piling lots of small payloads into the spare corners around big ones has turned out a lot cheaper than launching them all individually.

All in all, I think that the mothership is a great piece of technology. The thinking behind the orbiter suite has its flaws, but a mix of "super-size Pegasus" for at least some economy of scale, and multi-stage spaceplane (forget all-in-one) for the first low-gee launch service, might just prove viable.

 

[Hobbes]

1. 10% of boiloff in the ~2 minutes that the stage runs? For an F9 that's 50 tons of LOX changing phase. That seems far higher than the boiloff observed in the minutes before launch.
2. You might be able to fly around weather patterns, but you still have to apply for an exclusion zone where your first stage will impact (and make sure that zone is actually empty before you launch).
3. G-load is highest at stage burnout, lowest at takeoff. Replacing the first 30 seconds of the launch with an airplane ride doesn't gain you anything there.

 

[blackstar]

A mothership can keep it topped up, allowing the later-stage tanks to be 10% smaller. That allows a significantly bigger payload and/or higher orbit.

So this aircraft is equipped to top off the tanks of a rocket carried under the wing?

 

[steelpillow]

1. 10% of boiloff in the ~2 minutes that the stage runs? For an F9 that's 50 tons of LOX changing phase. That seems far higher than the boiloff observed in the minutes before launch.
2. You might be able to fly around weather patterns, but you still have to apply for an exclusion zone where your first stage will impact (and make sure that zone is actually empty before you launch).
3. G-load is highest at stage burnout, lowest at takeoff. Replacing the first 30 seconds of the launch with an airplane ride doesn't gain you anything there.

1. What you see before launch is only the water vapour and ice crystals condensed out of the air by the cold gases, the volume of cold gas roaring out of the vents is a lot higher.
2. Not if your first stage uses runways. You probably mean second stage, but that is no different from a rocket so not relevant to any comparison.
3. No. Replacing the 1st stage with a plane avoids the G load peak at first stage burnout. Other, wasteful techniques are necessary to reduce peak G for the later stages, but those are not the supremely thirsty stages.

So this aircraft is equipped to top off the tanks of a rocket carried under the wing?

Probably not. But it would hardly be rocket science to modify it. Think of it as an option in case a cryogenically-fuelled payload comes along.

 

[Michel Van]

here is Scott Manley analysis of Stratolaunch with help of Kerbal

https://youtu.be/yw84qJIGZeo

 

[TomcatViP]

Don't forget that Stratolaunch will service the rocket industry like transporting bulky components from one place to another relatively more easily than piggy backing it on an aircraft that would age faster (used airframe) and invariably requests more dedicated maintenance and logistics.

Also, the possibility to escape somewhat the uncertainty linked to the weather plaguing launch sites helps you to narrow your launch windows, relocate from northern to equatorial hemisphere, disseminate your launch across various site to face regulations and meet better any time constraints that might prove critical.

I think that for a national industry that has cut itself de facto from foreign cooperation, a service like Stratolaunch could be able to provide will invariably meet a market. Now, it might be that it is all that matters to continue pouring money in the project.

 

[Hobbes]

1. 10% of boiloff in the ~2 minutes that the stage runs? For an F9 that's 50 tons of LOX changing phase. That seems far higher than the boiloff observed in the minutes before launch.
2. You might be able to fly around weather patterns, but you still have to apply for an exclusion zone where your first stage will impact (and make sure that zone is actually empty before you launch).
3. G-load is highest at stage burnout, lowest at takeoff. Replacing the first 30 seconds of the launch with an airplane ride doesn't gain you anything there.

1. What you see before launch is only the water vapour and ice crystals condensed out of the air by the cold gases, the volume of cold gas roaring out of the vents is a lot higher.
2. Not if your first stage uses runways. You probably mean second stage, but that is no different from a rocket so not relevant to any comparison.
3. No. Replacing the 1st stage with a plane avoids the G load peak at first stage burnout. Other, wasteful techniques are necessary to reduce peak G for the later stages, but those are not the supremely thirsty stages.

I wrote my previous post assuming that they would launch a two-stage rocket. You seem to be assuming they'll use a single-stage rocket. The announcement doesn't say either way. A single-stage rocket would be a very ambitious strategy - something nobody has pulled off yet.

1. too tired to do the math right now. I do have one data point: in expander-cycle engines, the LOX has to be heated to provide enough tank pressure. 50 tons of boiloff in 2 minutes would be easily enough to provide tank pressure without extra heating. That suggests the figure is too high.

2. I mean the first rocket stage, obviously. And you need to file a NOTAM for ALL rocket stages that crash on land/in the ocean. You were suggesting flexibility of operations by responding to weather. I'm saying they can't do that because they have to file NOTAMs with so much lead time they can't adjust their flight plan en-route.

3. The aircraft is not a replacement for the first stage. It just makes the first stage a bit smaller. An F9 first stage separates at 1600 m/s. This aircraft will go maybe 300 m/s. If you could air-launch a Falcon 9, you'd make the first stage 20% shorter. That's all the savings you get from a subsonic air launch.

2 and 3 would be different if the rocket were to be a single-stage design.

Looking at the drawings, there are several horizontal lines that suggest to me it's a 2-stage vehicle.