Stratolaunch

[topspeed3]

Not enough advantage. That is why they wanted a Falcon 5 as a drop rocket at the beginning.
And, it would not have been able to carry a DreamChaser size spacecraft.
Wing loading has no bearing on getting to orbit.

So the soviets were wrong then ?

View: https://www.youtube.com/watch?v=VFRAx12TLTY&t=2s

 

[quellish]

Stratolaunch can be rented I assume.

Can it?

Two words:
Party Plane!

 

[Byeman]

So the soviets were wrong then ?

Did they build one to valid the concept? And a drop tank on vehicle means it is not SSTO.

And the point of discussion before you went off on a tangent. Sierra will win the "space race". Stratolaunch has no orbital capability in work. Sierra has a spacecraft that will be delivered to the launch site this year

 

[bobbymike]

Leveraging Public-Private Partnership to Meet the Hypersonic Challenge

Developed by Stratolaunch, Talon-A is designed to operate for sustained periods in the atmosphere at more than five times the speed of sound.

www.defensenews.com

 

[TomcatViP]

Unless I missed something, there is still a full mission profile to be flown before they can deem it a reusable test bed. To my knowledge, no landing have been demonstrated.

Just wondering b/w, why hasn't Boeing offered an atmospheric X-37?*

Spoiler: yes, I know, I know...

View: https://youtu.be/EL7Qw5STHac?si=hIhJeFQaqBYf0uNK

 

[Byeman]

Unless I missed something, there is still a full mission profile to be flown before they can deem it a reusable test bed. To my knowledge, no landing have been demonstrated.

Just wondering b/w, why hasn't Boeing offered an atmospheric X-37?

What is that exactly? What is there to "offered"? What need is there?
X-37 is a spacecraft. it has little propulsion capability. It is only aerodynamic enough to glide from entry. It is not meant for sustained atmospheric flight.

 

[TomcatViP]

good side and front view of Talon-A:

 

[OliverSedlacek]

The debate rages on, and one of these days I'm going to crunch some numbers of my own.
What can't be disputed is the minimal altitude and velocty gains you get (5% and 3%), but if you save 3% of your rocket fuel you do get a compounding effect.
What interests me more is the idea that launching into an atmosphere of only 25% ground level should open up the possibility of using air breathing jets to get up to Mach 5, so now you're at 20% of orbital velocity and you haven't had to use up any oxidiser yet.
The gains aren't game changing, but still useful.

 

[Byeman]

The debate rages on, and one of these days I'm going to crunch some numbers of my own.
What can't be disputed is the minimal altitude and velocty gains you get (5% and 3%), but if you save 3% of your rocket fuel you do get a compounding effect.

It doesn't really compound because the horizontal mounting leads to design inefficiencies and compromises.

What interests me more is the idea that launching into an atmosphere of only 25% ground level should open up the possibility of using air breathing jets to get up to Mach 5, so now you're at 20% of orbital velocity and you haven't had to use up any oxidiser yet.The debate rages on, and one of these days I'm going to crunch some numbers of my own.

the issue is that there are no off the shelf jet engines. and it needs to be less than 25% atmosphere due to heating

 

[Scott Kenny]

I still don't understand why we need a 250 mt hypersonic testbed... what, it weights 2.5 mt ? 0.25 mt ? so why use Roc to launch it then ?

Verifying the flex models for what happens when you drop a couple tons from the center wing.

Talon A is 2.7 tons, for which Roc is clearly overkill. They propose to be able to launch three at a time, which would be an interesting test scenario, but not exactly one in high demand.

They've also got in mind the end state Talon Z, supposedly an orbital payload delivery platform. But then you're back to wondering how this is better that Virgin Orbit. Or, indeed, any number of low-cost launchers.

Roc is available and designed for purpose, if expensive to use as a launcher.

I'm assuming that Talon A is mostly getting done to keep money flowing and to verify their flex models as they drop things from the center wing under flight loads.

If it is true that AN-225 is no more...Roc is the Only big 6 jet flying...yes, B-52 has 8, I know...

Bit of a difference between 8x17klbs on the B52 and 6x56klbs on the Roc.

They could at least have dropped a 250 mt mockup. It would justify the giganormous carrier a little better.

Gotta make sure their models for how the center wing responds to the drop are accurate with lighter stuff first.

look that news from Stratolaunch
i afraid the days of the Roc are number (the Carrier plane not Actor)

https://twitter.com/x/status/1661765488324558848

View: https://twitter.com/Stratolaunch/status/1661765488324558848

Different jobs. Ah, and Cosmic Girl is just using the "engine transport pylon" already existing on the 747.


=====================
For the up-engining, I'd look at keeping the same engine models (PW4000s), but going to the bigger fan diameters. It's currently running PW4056s that have a 94" diameter fan, though they could trade engine models to 62klbs thrust without too much work. The trivial step up would be to the 100" fan versions that make about 68klbs, that were designed for the Airbus 330. The Fecking 'Uge! step up would be to the 112" fan versions that make 74k-98klb thrust each, designed for the 777.

Yeah. Six engines as used on a 777.

 

[NMaude]

Yeah. Six engines as used on a 777.

That would require a major design change in the 777's wing-structure in order for each wing to be able to accommodate three engines instead of one engine.

 

[Scott Kenny]

That would require a major design change in the 777's wing-structure in order for each wing to be able to accommodate three engines instead of one engine.

No, putting those engines on the Roc wings. (Though I suspect that the Roc outer wings are straight off a 747 and just using the carry pylon inboard of the engines as a power pylon on both sides.)

 

[Byeman]

No, putting those engines on the Roc wings. (Though I suspect that the Roc outer wings are straight off a 747 and just using the carry pylon inboard of the engines as a power pylon on both sides.)

new wings

 

[Scott Kenny]

new wings

Sweet, that probably makes sticking the 112" fans on there easier.

 

[F119Doctor]

All it takes is $$$$. ROC was built with a lot of take-off components from a couple of retired B747s, thus the 4056 engines.

 

[Scott Kenny]

All it takes is $$$$. ROC was built with a lot of take-off components from a couple of retired B747s, thus the 4056 engines.

Yup. But I'm sure there's a few early 777s coming up on retirement soon that could donate their engines, if Stratolaunch gets something to drop that's big enough to require more horsepower.

 

[publiusr]

Think that second Antonov 225 could handle those?

Less spindly.

It is still in pieces. A cranked upward, gull like re-design for wings that still allow for good ground clearance just in case an even higher bypass monster comes along.

Unlike Roc, this could be used for normal cargo missions.

Keep the top mount Buran type hard points...just in case someone needs a trawler flown to a new port

 

[Flyaway]

https://twitter.com/x/status/1796199286142857293

View: https://twitter.com/stratolaunch/status/1796199286142857293

Today Roc begins its flight envelope expansion series, the 16th flight for the world’s largest aircraft. This test series is an effort to advance the demonstrated capabilities and performance of the aircraft, and ultimately expand the Talon-A hypersonic testbed’s performance range. We’re also utilizing the series to train new team members on flight operations, and to keep our current operations team sharp as we prepare for TA-2’s flight later this year.