Simple Merlin-derived SSTO

[PB666]

7 hours ago, Nibb31 said:

In other words, magic.

Without control surfaces, it would either go nose-first (like a nuclear warhead) or bottom first (bye bye engine). You would need it to look something like ESA's IXV:

Where was this reentry vehicle designed.

 

[meve12]

Have you considered using a maglev sled for launching? Sorta a StarTram-lite.

Should let you get to Mach 1 or 2 straightaway, without needed a run-up with the engine. How does that effect things?

[meve12]

Also:

11 hours ago, Nibb31 said:

...which has control surfaces and a blunt reentry shape. If only it could actually produce enough lift to glide back to landing...

The problem is that you want to design a vehicle that with too many different (and contradictory) flight envelopes:

• Vertical launch
• Orbit
• Reentry
• Hypersonic glide
• Subsonic glide
• Horizontal landing

It's nearly impossible to design an airframe shape that can operate gracefully in all those different environments. Plus, you want it to be SSTO and have a positive payload fraction. 

I have to agree with him. The last three regimes especially are going to be problematic.

...Suppose we use a biconic shape for reentry, with the ability to "open" a section covering the intakes like a flower?(This section would be just aft of the cone.)

On the way up, you open that section to enlarge the air intakes to scoop more air at higher altitudes-on the way down, after reentry, you open it more fully to stabilize the craft butt first, and land vertically on the engine.

EDIT: for general idea of shape:

Edited May 18, 2016 by meve12

[Nibb31]

10 hours ago, PB666 said:

Where was this reentry vehicle designed.

CNES and Thales Alenia Space.

Believe it or not, the Russian BOR/Mig-105's nickname was "Lapot", which I think, means "clog".

The blunt "shoe" nose is much better for reentry than sevenperforce's pointy nose design because you want drag slow you down. Which is contradictory to a launch configuration where you want to actually minimize drag. 

Edited May 18, 2016 by Nibb31

[wumpus]

7 hours ago, Nibb31 said:

CNES and Thales Alenia Space.

Believe it or not, the Russian BOR/Mig-105's nickname was "Lapot", which I think, means "clog".

[pict deleted]

The blunt "shoe" nose is much better for reentry than sevenperforce's pointy nose design because you want drag slow you down. Which is contradictory to a launch configuration where you want to actually minimize drag. 

Any idea how much drag you could lose with just a fairing over the "shoe"?  A fairing on a HL beastie might seem a little odd, but as long as you have contradictory aero requirements it sounds like it should be on the table.  Hope you didn't need the lift, in that case you are pretty much stuck with the design (which I'm sure is why these planes have it).

[Thor Wotansen]

How hard would it be to put extendable control surfaces around the tail and smaller ones around the nose that extend in reentry to provide drag, control, and heat shielding?  Something that would approximate the shape of the "clog" nose and provide heat shielding when fully deployed, but also bee flush with the aerodynamic lines for launch and conventional runway landing.  The rear ones would also provide aerodynamic control for low atmosphere maneuvering.

[sevenperforce]

I think the trick is to use a biaxial or even triaxial configuration. One axis minimizes drag for vertical takeoff (perhaps with some body lift to counteract gravity drag in an airbreather) and one axis provides high drag and/or lift for re-entry and gliding flight.

[Nibb31]

7 hours ago, sevenperforce said:

I think the trick is to use a biaxial or even triaxial configuration. One axis minimizes drag for vertical takeoff (perhaps with some body lift to counteract gravity drag in an airbreather) and one axis provides high drag and/or lift for re-entry and gliding flight.

Congratulations! You have just invented the capsule!

[cantab]

On ‎14‎/‎05‎/‎2016 at 2:44 AM, todofwar said:

If only there was some kind of software or game an amateur like me could use to demonstrate what I mean. Oh wait!

Now get RSS and RO and do it there

[sevenperforce]

7 hours ago, Nibb31 said:

Congratulations! You have just invented the capsule!

Now we just have to make it bigger and put engines on it!

Oh, hello there, SERV.

[Thor Wotansen]

Another thing you could do is deploy a ballute (or however you spell that) in the upper atmosphere to slow down before the hot and heavy part of reentry.  I'm not sure that they could be recoverable but it's a cheap(ish) and easy way to go.

[sevenperforce]

33 minutes ago, Thor Wotansen said:

Another thing you could do is deploy a ballute (or however you spell that) in the upper atmosphere to slow down before the hot and heavy part of reentry.  I'm not sure that they could be recoverable but it's a cheap(ish) and easy way to go.

Any in-practice examples of this?

[A Fuzzy Velociraptor]

5 hours ago, sevenperforce said:

Any in-practice examples of this?

Armadillo Aerospace has used a ballute in the past. I dont know of any other space vehicle uses though they have been used for bomb retardation.

It wont let me post both at the same time or edit so sorry if this doesnt merge my posts.

Stig A III Jan 28 2012

Edited May 20, 2016 by A Fuzzy Velociraptor

[meve12]

On 5/19/2016 at 6:13 AM, sevenperforce said:

Now we just have to make it bigger and put engines on it!

Oh, hello there, SERV.

Sevenperforce, don't mean to toot my own horn, but have you considered this?

On 5/18/2016 at 6:28 PM, meve12 said:

Have you considered using a maglev sled for launching? Sorta a StarTram-lite.

Should let you get to Mach 1 or 2 straightaway, without needed a run-up with the engine. How does that effect things?