Strato launch airplane

[flatbutt]

Not being an engineer I wonder if this is worth the effort?

https://www.washingtonpost.com/news/the-switch/wp/2018/04/16/it-would-be-the-worlds-largest-airplane-its-being-built-by-a-billionaire-and-its-getting-ready-to-fly/?noredirect=on&utm_term=.8a35ccc59072

[Tervuren]

How it works, is the airplane doesn't have to carry its own oxidizer(weight).

For the airplane it uses the atmosphere to get to that altitude, with initial velocity, and punching from a much thinner atmosphere the rocket doesn't have to carry as much fuel(weight).

[Seahawk]

Originally Posted by Tervuren

How it works, is the airplane doesn't have to carry its own oxidizer(weight).

For the airplane it uses the atmosphere to get to that altitude, with initial velocity, and punching from a much thinner atmosphere the rocket doesn't have to carry as much fuel(weight).

As an old flight test guy, there is the above and the fact that the launch aircraft will be flying at 250 plus knots...overcoming a static, ground based vertical launch is an engineering hump and drives design of virtually everything on a rocket.

There is nothing really special about the design of the Stratolaunch other than it's size. The control laws must be amazing.

[flipper35]

Others have been doing similar launches with smaller craft, this one just puts a bigger rocket on the belly.

[GH85Carrera]

That would be a cool aircraft to get a tour of the insides. So another billionaire will have a bigger aircraft than the billionaire Howard Hughes from a few generations ago.

[onewhippedpuppy]

Originally Posted by GH85Carrera

That would be a cool aircraft to get a tour of the insides. So another billionaire will have a bigger aircraft than the billionaire Howard Hughes from a few generations ago.

I was lucky enough to tour it as part of a sales capability visit. The scale is something that has to be seen in person to understand. You cannot see the entire aircraft from any single point in the hangar. Standing on the wing between the fuselages and looking in each direction is puts it into perspective. Because they have re-purposed the systems from several 747s the cockpit is rudimentary, basically an old 747 crammed into a strange looking composite tube.

It's a very interesting program that is very much a billionaire's pet project, there is some economic viability to their business case but it's not a slam dunk. The selling point is that the majority of a ground launched rocket's energy is expended during the first stage of the launch, which is roughly equivalent to the launch parameters of the ROC (carrier aircraft). By essentially skipping stage 1 you can have lighter space vehicles, with more payload capability than a rocket. The ROC is envisioned to eventually carry three spacecraft and because it is an aircraft, can vary the launch conditions to put spacecraft into different orbital inclinations. Using a ground based launch pads, different orbits require different launch locations, whereas Stratolaunch can put multiple spacecraft into multiple orbits on a single flight. It also removes a lot of the risk associated with weather over the launch pad.

[Tervuren]

I had not thought of the weather/location perspective, very useful in that respect alone.

[flatbutt]

Stage 1 is used to overcome the initial launch hump, OK. Does that mean that Stages 2 & 3 alone are able to achieve escape velocity?

[911_Dude]

Looks like a huge amount of potential twisting moment in the wing center section. Wonder why they didnt have the tail section connect? Would not want to fly it with a couple of engines out on one side.

Does the pilot and copilot each get there own fuselage? jk

[onewhippedpuppy]

Originally Posted by flatbutt

Stage 1 is used to overcome the initial launch hump, OK. Does that mean that Stages 2 & 3 alone are able to achieve escape velocity?

I'm not sure how many stages the spacecraft will have, but yes. It takes a massive amount of energy to get a payload, fuel, and rocket from sitting on the ground to 40,000 ft. This shortcuts all of that.

Originally Posted by 911_Dude

Looks like a huge amount of potential twisting moment in the wing center section. Wonder why they didnt have the tail section connect? Would not want to fly it with a couple of engines out on one side.

Does the pilot and copilot each get there own fuselage? jk

It's a freaking tank. I believe the tails are separated for simplicity of systems and to avoid wake turbulence from the spacecraft when they launch. I didn't get to go in, but apparently the left side fuselage is basically empty.

[svandamme]

First flight

I still think it's freaky to have 2 big bodies connected like that without a link in the back.
Even with normal turbulance most big planes flex and twist a little bit, but this is 2 planes joined at the hip so to speak...




I'de like to see a camera mounted on the right elevator of the left body
pointing at the right side.. to see how much they move independantly from eachother

I can only imagine that there are serious restrictions about what kind of weather it can take.

[svandamme]

well sure, but you do agree that any kind of deflection of the rear
with such a long fuselage
works like a big f'ing lever that twists the connecting point.. right?

It's like twisting somebody's arm , it doesn't matter how big his biceps is, if you got him at the right end and pull in the wrong direction.. it's gonna hurt.

Now I suppose having the wing in the middle of the fuselage, with a nose section almost as long as the tail will help in that respect. Like a counter weight..
the tail is like 25-30 meters... and the those elevators can exert quite some force..


But I doubt this plane is going to be flying in any kind of stormy weather, I wouldn't want to be on it in heavy turbulence...
or software failure in the control box

[berettafan]

that surely doesn't look like it should stay together long.

[LEAKYSEALS951]

Super cool concept, surprised they didn't do this sooner in regards to stage one rocket fuel needs.

Perhaps that design is safe, but it gives me the heebee jeebies watching it fly. I kind of want to cringe, look away, but yet can't when it flys- thinking about all those forces over the middle section.

Hope it works well!

I have obtained secret footage of left side fuselage controls:

[Jolly Amaranto]

Super cool concept, surprised they didn't do this sooner in regards to stage one rocket fuel needs.

Allegedly, the X-15 launched from a B-52 was capable to make it into orbit with some modifications.

[IROC]

Originally Posted by LEAKYSEALS951

Super cool concept, surprised they didn't do this sooner in regards to stage one rocket fuel needs.

Not a new idea for sure. OSC has been doing something similar for a long time...

https://en.wikipedia.org/wiki/Pegasus_(rocket)

[red-beard]

Originally Posted by Tervuren

How it works, is the airplane doesn't have to carry its own oxidizer(weight).

For the airplane it uses the atmosphere to get to that altitude, with initial velocity, and punching from a much thinner atmosphere the rocket doesn't have to carry as much fuel(weight).

There is more to it. Rocket nozzles designed to work in atmosphere are not efficient shapes for near vacuum and the reverse is also true. By getting to 50-60K feet (10-12 miles, 15-18km), the atmosphere is thin enough that you don't have to make a compromise design. This further reduces the amount of propellant and oxidizer needed.

[Zeke]

RE: connecting the 2 fuselage's:

[dw1]

New embodiment of several old old ideas.

Notably, the He-111Z had success as a glider tug for the Me-321.

The He-111Z did not have a "bridging" tailplane, but the Me-109Z and the P-82 (all of which were twin fuselage aircraft) did.

And, of course, rockets being launched from aircraft dates back to the B-29/X-1 combo.

The ALBM (air-launched ballistic missile) testing dates back to the 1970s, notably with the testing of a Minuteman 1b ICBM dropped/launched from a C-5A Galaxy.

[onewhippedpuppy]

Originally Posted by LEAKYSEALS951

Super cool concept, surprised they didn't do this sooner in regards to stage one rocket fuel needs.

Perhaps that design is safe, but it gives me the heebee jeebies watching it fly. I kind of want to cringe, look away, but yet can't when it flys- thinking about all those forces over the middle section.

Hope it works well!

I have obtained secret footage of left side fuselage controls:

Cute kid! The left side is systems only, not even pressurized.