Spaceplanes - Cases for and Against

[Eric Mc]

Having just watched another enjoyable TMRO broadcast on this topic, I was wondering what views the space cadets here on PH might have on the subject.


https://www.youtube.com/watch?v=x00MCQWBFV8

[Beati Dogu]

Good question. I subscribe to this Youtube channel & they deserve more subscribers than they have.

The bloke on the left, Ben, is married to Cariann on the right & they both work for SpaceX in LA. They don't mention that for obvious NDA reasons and didn't comment on the news about the Falcon 9 loss. He's a Video Systems Engineer for things like the launch webcasts.


As for space planes, they cover the pros and cons very well.

As a kid I remember seeing the Space Shuttle on the back of the 747 and assuming they were going to launch them into space from altitude like that. So I was disappointed to see the first actual launch was from a pad, with a bloody great fuel tank and boosters attached.

HOTOL sounded promising, but nothing became of it. Skylon is it's successor and seems to be treading water as well.


Swiss Space Systems' idea to have a small, unmanned rocket plane launched from atop and Airbus A300 aircraft sounds more like it.



https://www.youtube.com/watch?v=e2ooKEWCRQY

http://www.s-3.ch/en/mission-goals

That's really the only reason having wings, or at least a lifting body and vestigial wings, makes sense to me.

[scubadude]

Eric Mc said:

Having just watched another enjoyable TMRO broadcast on this topic, I was wondering what views the space cadets here on PH might have on the subject.

https://www.youtube.com/watch?v=x00MCQWBFV8

IMO We haven't yet had a "proper" spaceplane yet, the shuttle and others are (arguably) rocket launched gliders not Space capable Planes, ie- they don't take off from runways or have major cross range.

While SpaceX are making waves with rockets that can be reused it hard to see people pouring the required funds into spaceplanes.

Funding Skylon is really the only way forwards IMO, not sure why the hosts where so negative towards it?



Childish aside- linked video is proof why newscasters use desks with fronts... what has been seen cannot be unseen :-O

[Eric Mc]

scubadude said:

IMO We haven't yet had a "proper" spaceplane yet, the shuttle and others are (arguably) rocket launched gliders not Space capable Planes, ie- they don't take off from runways or have major cross range.

While SpaceX are making waves with rockets that can be reused it hard to see people pouring the required funds into spaceplanes.

Funding Skylon is really the only way forwards IMO, not sure why the hosts where so negative towards it?



Childish aside- linked video is proof why newscasters use desks with fronts... what has been seen cannot be unseen :-O

I think the only negativity towards Skylon was in relation to what happens with a catastrophic engine failure. But to be honest, a catastrophic engine failure on any space vehicle is likely to result in the loss of the vehicle.

I think with any winged spaceplane type vehicle, getting a crew away from an explosive event to safety is always going to be problematic. On the Space Shuttle, they just gave up on any safety measures and decided "It will never happen". Not the right answer - it turned out.

A capsule can always be jettisoned and used as an escape pod - as has been used twice in the history of manned spaceflight..

[Eric Mc]

The US military never retrieved anything with the Shuttle. Indeed, they hardly conducted any of the grandiose plans they had for it.

Getting large, heavy, craft into orbit requires a huge amount of energy. The Shuttle orbiter weighed just under 90 tonnes. Accelerating a mass like that to 17,500 mph and an altitude of over 200 miles is just an enormous task requiring enormous expenditure of energy.

And it always will be - no matter how you go about doing it.

[Foliage]

The main 2 advantages from my knowledge of space planes, specifically single stage to orbit (SSTO) is that

A. Wholly and completely reusable
B. Can carry less fuel by getting close to the required escape velocity while at an altitude to air breath hence not having to carry oxidiser and it can get up to the thinner air (less drag) at a reasonable speed (say mach 1) then accelerate up to the required speed (mach 20+) to attain orbit.

But we aren't material and engine technology wise quite there yet to be able to do this.

[Eric Mc]

ash73 said:

Eric Mc said:

The US military never retrieved anything with the Shuttle.

You're probably right but I doubt we would know if they did. It was certainly one of the unique capabilities of the Shuttle.

Hiding activities in earth orbit is virtually impossible. If the Shuttle was retrieving a previously launched satellite (or even a test target it had placed over the side), it would be relatively easy for spotters on the ground to see both the Shuttle and its intended retrieval target.

At the moment, the movements of the unmanned mini-Shuttle X-37 are being monitored by amateur satellite spotters - and no doubt by more serious observers too - such as the Russians and the Chinese.

It was this retrieval capability that scared the Russians so much - and prompted them to start their Buran programme.
As it turned out, after the Challenger accident, the USAF backed off the Shuttle pretty quickly and instigated no new Shuttle based programmes. When the Shuttle returned to flight in 1988, the only DoD flights conducted were those that had been scheduled pre 1986.

[scubadude]

Eric Mc said:

I think with any winged spaceplane type vehicle, getting a crew away from an explosive event to safety is always going to be problematic. On the Space Shuttle, they just gave up on any safety measures and decided "It will never happen". Not the right answer - it turned out.

A capsule can always be jettisoned and used as an escape pod - as has been used twice in the history of manned spaceflight..

This is true but I don't see why a ground up design couldn't include a escape capsule (ala F-111) during climb to orbit a space plane is a rocket with wings (unless cunningly folded or in a fairing) there is no reason it can't have a crew abort system.

In the shuttles case, having the crew compartment alongside the fuel tank was an issue in this regard, although I believe they did originally look at an inline stack design that would have offered the crew abit more seperation it was abandoned (I expect Eric has an image :-)

I suspect the real question is- Do we need a space plane? Currently we don't.

[SystemParanoia]

watching now...

i also like the code monkeys podcast for a not so factual lighthearted natter on space stuff

https://www.youtube.com/channel/UCFtovEipsP-fxSVD-...

[Eric Mc]

scubadude said:

This is true but I don't see why a ground up design couldn't include a escape capsule (ala F-111) during climb to orbit a space plane is a rocket with wings (unless cunningly folded or in a fairing) there is no reason it can't have a crew abort system.

In the shuttles case, having the crew compartment alongside the fuel tank was an issue in this regard, although I believe they did originally look at an inline stack design that would have offered the crew abit more seperation it was abandoned (I expect Eric has an image :-)

I suspect the real question is- Do we need a space plane? Currently we don't.

They did indeed look at a simpler stacked method during the early configuration studies -



The other major issue is that rocketing a winged vehicle at massive acceleration away from an exploding booster is likely to rip the wings off the vehicle.

Indeed, in the Challenger accident, the orbiter broke up because of the excessive aerodynamic loads placed up in as it was pushed away from the collapsing External Tank.
During launch, having wings sticking out into the airflow really puts limitations on the ascent profiles possible and the abort options.

[annodomini2]

Foliage said:

The main 2 advantages from my knowledge of space planes, specifically single stage to orbit (SSTO) is that

A. Wholly and completely reusable
B. Can carry less fuel by getting close to the required escape velocity while at an altitude to air breath hence not having to carry oxidiser and it can get up to the thinner air (less drag) at a reasonable speed (say mach 1) then accelerate up to the required speed (mach 20+) to attain orbit.

But we aren't material and engine technology wise quite there yet to be able to do this.

This is what they are aiming for with Skylon, whether they achieve it remains to be seen.

But I see the issues being financial and political rather than technical, certainly at this stage.

[Beati Dogu]

A look at Sierra Nevada Corporation's Dream Catcher space plane:

https://www.youtube.com/watch?v=0bb4d3bjB70


Love the special cockpit equipment they installed.

[Beati Dogu]

Beati Dogu said:

Swiss Space Systems' idea to have a small, unmanned rocket plane launched from atop and Airbus A300 aircraft sounds more like it.

The founder & CEO of this company, Pascal Jaussi, seems to have upset someone. Just over a week ago, two armed men forced him to drive his car into a Swiss forest, where he was beaten up, doused in an accelerant, set on fire & left for dead. He's currently in a hospital in Lausanne with burns to 25% of his body. He's out of immediate danger, but obviously still in a bad way.

Apparently he'd been receiving threats related to the company and they had a break in which some equipment was damaged.

I wonder what the hell that is about.

http://www.thelocal.ch/20160905/swiss-space-firm-b...

[Eric Mc]

Very strange goings on there. You do get odd characters getting involved in space projects sometimes. In the late 1970s there was a German/Zaire (yes - Zaire) project called OTRAG which was supposed to establish a commercial launch vehicle and launch site in west Africa.

That was very murky and there were hints of corruption an illegal activities. As far as I know, it never came to fruition.

[Beati Dogu]

Now that would have been a Rumble in the Jungle.

[Eric Mc]

It was around the same time. Zaire really wanted to put itself "on the map" at that time.

https://www.youtube.com/watch?v=vbYwBy7BbXE

[RizzoTheRat]

Eric Mc said:

During launch, having wings sticking out into the airflow really puts limitations on the ascent profiles possible and the abort options.

The design on the right looks like it would be very unstable with that much wing ahead of the center of mass.

I think a 2 stage design like White Knight/Spaceship 1 and the follow on Virgin iterations is likely to be the most sensible way to do it (and AFAIK the only the successful one so far as the X-15 used a similar approach), it massively reduces the amount of mass the vehicle has to carry, but will need to be a lot bigger than anything tried yet, LEO needs over 9km/s, X-15 managed 2km/s.

Of course the bulk of my experience in such matters comes from playing KSP...
https://xkcd.com/1244/

[Beati Dogu]

Beati Dogu said:

The founder & CEO of this company, Pascal Jaussi, seems to have upset someone. Just over a week ago, two armed men forced him to drive his car into a Swiss forest, where he was beaten up, doused in an accelerant, set on fire & left for dead. He's currently in a hospital in Lausanne with burns to 25% of his body. He's out of immediate danger, but obviously still in a bad way.

Apparently he'd been receiving threats related to the company and they had a break in which some equipment was damaged.

I wonder what the hell that is about.

http://www.thelocal.ch/20160905/swiss-space-firm-b...

It now appears that Mr Jaussi's "attack" last August was self-inflicted and he's now being investigated by a Swiss prosecutor.

Seems he may have staged it in a effort to save his company. It didn't work; Swiss Space Systems was declared bankrupt by a court in December.

http://www.swissinfo.ch/eng/justice_swiss-space-sy...

[Boring_Chris]

Eric Mc said:

Having just watched another enjoyable TMRO broadcast on this topic, I was wondering what views the space cadets here on PH might have on the subject.


https://www.youtube.com/watch?v=x00MCQWBFV8

Eric, I stumbled across this in some random far flung corner of the Internet and, for reasons I can't quite explain, thought of you.





Edit. apologies for the random and wasn't looking to derail an interesting thread.

Edited by Boring_Chris on Thursday 16th March 10:21

[Beati Dogu]

Meanwhile, the US Air Force's diminutive X-37B space plane continues to rack up the mileage.



It has been sneaking around up there since May 20th 2015. That's right, 2015.

If it makes it to the 25th March 2017, it will beat its own record of 674 days in orbit, set in 2014.

The Air Force is believed to have 2 of them and they're launched into space inside a full fairing on top of an Atlas V rocket.

https://www.youtube.com/watch?v=AeQbY4rkQJ8

When they're ready, they'll glide it back home like its big brother the Space Shuttle. They may even use the Shuttle Landing Facility at the Cape for this, although the previous 3 missions have all landed at Vandenberg AFB in California.