Dominic Gates
Seattle Times

Paul Allen’s monstrous Stratolaunch airplane finally rolled out of its hangar in Mojave, Calif., Wednesday, showing off its complete twin-hulled majesty for the first time.

It will now spend many months on ground tests ahead of a first flight. And it’s not expected to be used to launch a rocket into space — a mission that some observers are skeptical will ever make business sense — any sooner than 2019.


Two tugs pulled the 250-ton giant from the hangar where it was built for Allen’s Stratolaunch Systems company by Scaled Composites, the specialty airplane development firm founded by aviation pioneer Burt Rutan.

Over the past few weeks, mechanics removed the last of the three-story scaffolding that had surrounded the aircraft during construction, leaving the aircraft’s full weight to rest on its 28 wheels for the first time.

Jean Floyd, chief executive at Stratolaunch Systems, said in a statement that the empty airplane, powered by six used 747 engines, weighs approximately 500,000 pounds.

“That may sound heavy,“ Floyd acknowledged. “But remember that the Stratolaunch aircraft is the world’s largest plane by wingspan, measuring 385 feet. By comparison, a National Football League field spans only 360 feet.”

The plane — nicknamed the Roc, after a mythical Middle Eastern bird so big it could carry an elephant in its claws — will have a three-person crew: pilot, co-pilot and flight engineer.

They’ll be in the flight deck of the starboard fuselage, maneuvering the plane from far to the right of its centerline, while the port fuselage cockpit is empty and unpressurized.

Stratolaunch is intended to carry a rocket slung beneath the central part of the wing, between the two fuselages, and release it at 35,000 feet. The concept is that the rocket will then launch into space and deliver satellites into orbit.

For comparison, the empty weight of the world’s largest airliner, the double-decker Airbus A380 designed to carry around 550 passengers, is 610,000 pounds.


And the empty weight of Boeing’s largest jet, the 747-8, is a paltry 435,000 pounds.

Paul Allen’s aircraft is 238 feet from nose to tail, and it stands 50 feet tall from the ground to the top of the vertical tail.


It will carry about 250,000 pounds of fuel and a rocket payload of up to 550,000 pounds or 275 tons, giving it a maximum takeoff weight of 1.3 million pounds — equal to the fully loaded weight of the A380.

There’s plenty of skepticism about Stratolaunch’s business plan for delivering satellites to orbit using this behemoth plane.

Since Allen first put forward the idea in 2011, both Elon Musk’s SpaceX and Jeff Bezos’s Blue Origin have successfully pioneered new reusable ground-launched rockets that are already dramatically lowering the cost of access to space.

And the satellite business has changed, with demand shifting toward small satellites going to low earth orbit, not the huge, minivan-sized satellites that used to be standard.


The airplane may be simply too colossal and therefore too expensive to be used to launch smaller satellites.

Progess on the project has been slow. A year ago, Stratolaunch’s leadership indicated that it hoped for a rollout by the end of 2016.

Yet driven by Allen’s passion for space and science fiction and funded by his virtually bottomless purse — courtesy of co-founding Microsoft more than 40 years ago — construction of the airframe is complete and the Roc has finally emerged to the light of day.

Floyd on Wednesday laid out an extended timeframe, though he didn’t specify when the aircraft might first take to the air.

“Over the coming weeks and months” at the Mojave Air and Space Port, the aircraft will undergo “ground testing, engine runs, taxi tests, and ultimately first flight,” Floyd said.

“Stratolaunch is on track to perform its first launch demonstration as early as 2019,” he added.

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Not an engineer, but I would bet that thing is a disaster waiting to happen.
No way can I see that little center section of wing standing the huge forces that will be acting on it in flight.

quote:

Originally posted by cparktd:
Not an engineer, but I would bet that thing is a disaster waiting to happen.
No way can I see that little center section of wing standing the huge forces that will be acting on it in flight.

From the comments section:

Texan Forever

I'm a retired member of both the Society of Automotive and Aeronautical Engineers and the earlier American Rocket Society. Also The Society of Aerospace Medicine. I've designed aircraft all my life, starting with flying models in the early 1940's. I built from scratch and flew a model of the assymetrical Blohm and Voss German aircraft during the WW2 years. As expected, crazy as it looked, it flew beautifully. I instinctively can tell a lot about what is good design and what is bad, and can usually tell from just a first glance at a design where the flaws are, both aerodynamically and structurally.



This is an aerial monstrosity just waiting to come apart in flight and kill people. Obviously the weakest spot is the center wing section that structurally connects both halves. This inherently weak area must absorb all the torque stresses from keeping both fuselages joined, amplified by the fuselages not being further braced by a connecting tail surface like the WW2 P-38 and twin Mustang. Both sides of this huge aircraft will want to twist and bend independently from aerodynamic stresses, with only the center wing structure absorbing the immense concentrated torque stresses. It will break apart fairly soon. Also, the engines outboard of the two fuselages will add further stresses to the center wing trying to hold everything in place. At least two engines should have been located in the center section for better distribution of weight and thrust. But that would also have put even more stress in that area. This is a far worse design than the old 12-engined German Dornier flying boat of the late 1920's and early '30's. It might have been grossly under-powered but at least was structurally well engineered and very sturdy for its time.

Wow. I hope they bought up all the S&W Scandium to reinforce that middle section. They're going to need it!

I wonder how Scaled Composites has gotten away with all those crazy designs all these years.

http://www.scaled.com/hires_gallery/

I realize Rutan has retired, but I have to imagine his design principles have been thoroughly mastered.

I'm thinking, Howard Hughes Spruce Goose all over again. We'll see but I'm skeptical.

Jim

Whether or not this bird ever makes it off the ground, I have to give a lot of credit to the visionaries: Paul Allen, Elon Musk, Jeff Bezos and others are on the vanguard of space flight "for the rest of us." Up until now, space travel has been the providence of governments, and these guys in the commercial sector are changing not only the game, but how we think of the game.

quote:

Originally posted by cparktd:
Not an engineer, but I would bet that thing is a disaster waiting to happen.
No way can I see that little center section of wing standing the huge forces that will be acting on it in flight.

That's exactly what I thought, too. As a minimum why didn't they connect the rear horizontal stabilizers like on a P38? That center wing section must undergo fantastic torque and flex...then you're going to hang a payload on it? HIYAAAHHH!!!!!

Update: looks like Darthfuster posted a real aeronautic engineer's thoughts, but similar so great minds must think alike!

So I'll add, I think I know where the original concept came from, as in let's just bolt two airliners together, but the design minimalists must have pared the robustness right out to a point past safety...

Sure you might get it off the ground a few times, but eventually that center section will fail.

Size appears to be quite different from Rutan's designs.

This is why the test pilots get all the chicks

I spent about a year and a half working on fairing deployment and stage separation mechanisms for the launch vehicle when Orbital was the launch vehicle contractor. Yes, vehicle bending modes were a real concern. The biggest concern was the case of abort landing. Meaning a fully fueled launch vehicle was still attached to the carrier aircraft when an emergency landing was required. I don't think there was enough ground clearance for the landing gear to fully absorb the landing without dragging the launch vehicle on the tarmac.

I also remember seeing a Power Point presentation where the runways at Mohave and KSC were going to have to be modified. Stratolaunch is too large to be able to turn around on the existing runways and aprons.

If it works, the temptation to take some bimbos and bottles on one of the flights is going to be overwhelming.

quote:

Originally posted by cparktd:
Not an engineer, but I would bet that thing is a disaster waiting to happen.
No way can I see that little center section of wing standing the huge forces that will be acting on it in flight.

I'm thinking the same...but I've got to imagine the engineers have accounted for this. After all, I'm not an engineer, and I thought the same thing. All kinds of twisting and torque-vertical, horizontal, rotational, oblique...

But I'm not an engineer.

Unless it has excellent Digital Flight Control systems, it won't survive the maiden flight.

Those parts will scatter like a room full of sleeping cats when start pistol is fired.

So, the math gets funky.

3 axis squared X 2 bodies = 18 different directions at once. (and this is after driving and working for 16 hours, so, I may be way off)

It won't work. center section will twist right in half. This is surly not a "serious" design" . It is pure B.S. Next.

I didn't stay in a Holiday Inn Express last night, but I could design a plane a hundred times better that that....that would work!

absolutely no aviation expert here. But that thing just does not speak innovation to me. Taking two planes and making them one just does not do it for me.

quote:

powered by six used 747 engines

Appears as if the landing gears are used as well.

Is she dont fly, it's all the fault of the MIM parts. It should be fine once its in orbit.

On the other hand, what did they say about the Wright Brothers?

I could build an indoor race track in that hanger.