Discussion ARCA's flying ocean launch platform

[ISProgram]

That might be well and good, but you get those advantages to a maybe lesser, but still by no means insignificant degree for any air-launched or floating system without combining the too, and it still doesn't explain why anyone would want to submerge a rocket, filled with potentially cryogenic propellant and sensitive technology, in salt water for what has to be at least an hour, probably more, before launch.

I would also like to mention, that, looking at the launch video, the Haas' payload fairing (or at least most of it) is underwater. Why risk saltwater contamination of the potential payloads for the Haas' with this architecture?

I would also like to mention that I don't think the Haas' payload fairing will even maintain integrity, given that the IAR-111 will have to accelerate to at least >100mph to liftoff in a medium that's 2,500 times denser then air. The Haas' front end will be taking the brunt of all this, since it will be submerged in said medium.

 

[Loru]

I suspect that only initial studies has been done and picture/animation is just "licentia poetica" of the graphic artist.

 

[Hlynkacg]

Thats wrong. What is good for reducing RCS is actually very harmful to aerodynamics, including the performance at supersonic flight.

Exactly.

That wide flat body, hexagonal wing cross-section, and butterfly tail associated with the F-22/YF-23 aesthetic are all aerodynamically inferior options chosen to reduce radar cross-section rather than increase performance.

If your design objective is superior performance at trans and super-sonic speeds your aircraft will end up looking a lot more like The Concord or a F-14 Tomcat than a F-22.

---------- Post added at 15:58 ---------- Previous post was at 15:57 ----------

That might be well and good, but you get those advantages to a maybe lesser, but still by no means insignificant degree for any air-launched or floating system without combining the too, and it still doesn't explain why anyone would want to submerge a rocket, filled with potentially cryogenic propellant and sensitive technology, in salt water for what has to be at least an hour, probably more, before launch.

This too ^ :facepalm:

 

[ISProgram]

I suspect that only initial studies has been done and picture/animation is just "licentia poetica" of the graphic artist.

These pictures (and especially this) all seem to say otherwise (as in ARCA's pictures/animation are accurate). I think ARCA's going with this architecture...

 

[Urwumpe]

Well - it follows the area rule and the nose section has a lot in common with a MiG-29. But you also see that the aerodynamics are not very good - too many shock waves at Mach 2.5 already, usually, you try to hide as much of the aircraft as possible behind an initial shock at design speed.

Also, I am not sure if this shape could take off from water well. Or carry payload while taking off.

 

[orbitingpluto]

Why make it a sea-plane, why compromise aerodynamics and mass ratio to give it a low radar cross section? What role is this craft supposed to fill?

It's a launch vehicle for Bond villains.

 

[Hlynkacg]

It's a launch vehicle for Bond villains.

I think pluto just won the thread :lol:

 

[Hielor]

Saying that taking off from water lets you hit any inclination works for something like Sealaunch where you've basically got a mobile launch pad, but for an air release system? You can already get basically any inclination you want just by flying to another airport...

 

[Loru]

Also there is a problem of waves/sea conditions during launch. Seaplane can't land/take off wherever it wants. Waves has to be limited to certain size otherwise seaplane can be easilly ripped apart during landing/take off.

Good example is [ame="http://en.wikipedia.org/wiki/Boeing_314"]Boeing 314 (Clipper)[/ame] which was limited (IIRC) to 1 meter waves during landing.

You have to sacrifice lot of payload capacity to reinforce water part of fuselage to withstand stress during landing/take-off (especially part when you're constantly hitting wave tops at high speed).

 

[PhantomCruiser]

I was thinking of all the problems that Glen Martin had with the Seamaster

Problems can be fixed with enough time and money, but in a competitive field, will the "buy-back" ever be realized?

 

[n122vu]

Oh I wasn't saying I agree with their concept, or that it justified the water launch. The variable launch inclination was just one logical point I could think of as to why they would even want to in the first place.

 

[Hlynkacg]

Oh I wasn't saying I agree with their concept, or that it justified the water launch. The variable launch inclination was just one logical point I could think of as to why they would even want to in the first place.

Still doesn't explain the low radar cross section.

 

[Urwumpe]

Maybe they mentioned low RCS, because their vessel has a lot in common with the YF-23?

 

[RisingFury]

I think it's just a publicity stunt.

The entire thing looks more like a fighter jet than an air launch system.

 

[ISProgram]

I think it's just a publicity stunt.

The entire thing looks more like a fighter jet than an air launch system.

Exactly my thoughts. There just isn't enough justification for this architecture. I see a lot of different ways in which this system could've been different and still came close to the "supposed" performance they want out of this. Don't know what that performance is, but...

As for it looking like a fighter jet, it might have military applications/variants. But it seems like a publicity stunt, especially with those SpaceShip 1/2 style windows.

ARCA's really interesting me, that's for sure.

 

[boogabooga]

Another three months, another "private" spaceflight "start up" gets three pages of buzz on Orbiter forum with a pretty CGI animation and nothing else.



Also, just noticed that the youtube is from 2010. So, we haven't heard anything since then, so, yeah...

 

[Marvin42]

Another three months, another "private" spaceflight "start up" gets three pages of buzz on Orbiter forum with a pretty CGI animation and nothing else.



Also, just noticed that the youtube is from 2010. So, we haven't heard anything since then, so, yeah...

Although Romanian myself, I'm really sorry for the people that actually work there. From my following of ARCA's previous "missions" it seems to me the best that those guys made is a typical money-laundering machine. A balloon is the best "ship" they've launched. Right now they have built a 1:1 scale model of a nozzle from their future engine...unknown what future means to them.

 

[Urwumpe]

The chamber head doesn't look really solid. by the thickness of the plates and the bolts, maybe for 10-15 atm.

 

[Marvin42]

Eventually they settled to a rocket engine fuelled with LOX and kerosene T1 and a vacuum thrust of 32 tons (length of 1,7 m and a diameter of 1 m). The engine's total weight was expected 260 kg. Intended values are below.
On their website they say (quoted):

The long development time for this engine was considered unacceptable under the present circumstances.

 

[ISProgram]

The chamber head doesn't look really solid. by the thickness of the plates and the bolts, maybe for 10-15 atm.

It looks like the Venator...or the Executor. I don't know. All their engines (nozzles) look the same to me. Probably the former, based on your statement that it has "10-15" atm, with the Venator have 16 atm. The Executor goes much higher, in the range of 25-70 atm...

EDIT: You guys type fast!!!