Time to Think ‘Horizontal’ for Future Space Launches

On 22/09/2010 1:55 AM, wrote:
"Is firing a rocket from the ground straight up
into space the right way to do things?

It sure was in the 1950s and ‘60s and it
persists today. But it’s still expensive, fraught
with technical risk and dwindling into
obsolescence.

There could be an alternative on the horizon,
however, that incorporates the concepts of
railguns, scram jets and kinetic launching
into an innovative, reusable space launch
system for unmanned cargo."

See:

http://defensetech.org/2010/09/21/ti...pace-launches/



I can't help feeling that in the hands of NASA, this will just be
another way for vast amounts of tax-payer's money (not mine,
fortunately, since I'm not in the USA) to be given to aeronautics
companies who are more interested in being paid for activity than results.

Sylvia.

On 9/26/2010 6:18 PM, Sylvia Else wrote:

I can't help feeling that in the hands of NASA, this will just be
another way for vast amounts of tax-payer's money (not mine,
fortunately, since I'm not in the USA) to be given to aeronautics
companies who are more interested in being paid for activity than results.

In fact, the ideal situation for them is if the program gets canceled
before flying; then you can design something that you know can't work,
get paid for working on it, and know that it well never be finished...so
you won't get sued for defrauding the US government.

Pat

On 27/09/2010 5:44 PM, Pat Flannery wrote:
On 9/26/2010 6:18 PM, Sylvia Else wrote:

I can't help feeling that in the hands of NASA, this will just be
another way for vast amounts of tax-payer's money (not mine,
fortunately, since I'm not in the USA) to be given to aeronautics
companies who are more interested in being paid for activity than
results.

In fact, the ideal situation for them is if the program gets canceled
before flying; then you can design something that you know can't work,
get paid for working on it, and know that it well never be finished...so
you won't get sued for defrauding the US government.

Pat

Sounds like a good incentive for dragging it out as long as possible,
especially if it's meant to be man-rated.

Sylvia.

In article SeKdnSrsFsZS8ADRnZ2dnUVZ_j-
hdakotatelephone, says...

On 9/24/2010 6:47 AM, Jeff Findley wrote:

True, but then you wouldn't need the inflatable heat shield for the nose
of the ET, so that's not nearly complicated enough for Mook.

There is no need to put a heatshield on the nose; the plug nozzle engine
on the tail is heavy enough to make it fall into the atmosphere pretty
much tail-first anyway, and is already made out of heat resistant
materials to take the heat of the rocket exhaust.
Back when Philip Bono was coming up with the SSTO plug-nozzle engine
designs for Martin Aerospace like the Pegasus and Ithacus, reentry was
to be handled by ejecting some leftover LH2 from the center of the
bottom of the central plug and letting the cold gas form a sheath over
the bottom of the plug to prevent heating damage during reentry.
That's what's going on in this painting of a Pegasus reentering:
http://www.astronautix.com/graphics/p/pegasus2.jpg

Tell that to Mook. He's the one arguing for an inflatable nose heat
shield, not me.

Jeff
--
The only decision you'll have to make is
Who goes in after the snake in the morning?

In article
tatelephone,
says...

In articlefcbfe968-0bb0-46ce-a6bf-f5611a8d94d4
@l32g2000prn.googlegroups.com, says...

Yet, none were lost this way.

No, that's how the SNECMA Coleoptere was lost; they tried to to do a
vertical takeoff and landing in it, and it started tumbling over
sideways as it descended. The pilot ejected, and the out of control
aircraft ended up going almost horizontal before slamming into the
ground and exploding.
And that was the last you heard of the Coleoptere; the French canceled
it and never talked about it again. :-D

You'll confuse Mook with facts like this. In his mind, his napkin
drawing is absolutely perfect.

Jeff
--
The only decision you'll have to make is
Who goes in after the snake in the morning?

In article CtudnVJDw-
hdakotatelephone,
says...

On 9/24/2010 6:55 AM, Jeff Findley wrote:

The fact that this tail sitting technology has not been used in an
unmanned winged vehicle means you have no valid point.

Oh, it's pretty easy to do nowadays in a fairly small RPV; the problem
here is scale.

That and he wants to "land" on a vertical stand like some of the US tail
sitters from the 50's. I'd think more conventional vertical landing
gear would allow for landing on just about any open surface (i.e.
concrete), which is what DC-X did and what many of the small reusable
demonstrators (as seen on A-Rocket email list) are doing today. But
Mook just loves to do things the hard way, based on unproven 50's tech
rather than using current tech.

A largely empty ET is a huge, lightweight structure, and like I
mentioned before, any sort of a side wind, especially a gusty one, would
be a recipe for disaster.
One thing here is that the plug-nozzle engine on the bottom of the ET is
the only thing worth recovering from a economic viewpoint. The ET itself
is basically a big aluminum-lithium beer can, and by the time you stuck
effective recovery gear and a TPS on it, you will have raised its weight
so much that you will have severely compromised its ability to carry a
worthwhile payload into orbit. NASA realized this when they built the
Shuttle, which is why I've never seen a NASA proposal for a recoverable
ET since the Shuttle entered service near three decades ago.
Russia played around with a recoverable core stage for the Energia
launch vehicle with wings on it (very similar to this idea), but ditched
that idea also.

Well, that big empty can does make reentry easier. Heat shields for
small, dense vehicles/payloads are harder than heat shields for large,
less dense vehicles/payloads. The max temperature experienced by
something large and "fluffy" is quite a bit lower than something very
small and dense.

And it was going to glide-land horizontally, not try to descend
tail-first. If you stick wings on it, the only reason is to have it
glide-land; if it's going to land vertically, then there is no need to
stick wings on it.

Tell that to Mook.

So, why aren't we all flying those big SSTO plug-nozzle reusable
boosters like Philip Bono designed back in the 1960's?
Because there's a repetitive pattern one can notice in the "wonder
rockets" that are going to revolutionize space travel:

1.) Specific impulse of the new rocket engine to be used is overestimated.
2.) Fuel consumption of that engine to produce the desired thrust is
underestimated.

...and the big one:

3.) Total structural weight of the vehicle is _way_ underestimated,
particularly when its TPS weight enters the equation.

Mook insists his numbers are good, even though he openly admits that no
detailed analysis and design has been done. He's only done a very high
level parametric analysis to come up with his numbers.

That's why you end up with things like Black Horse that somehow has a
mass ratio identical to a Atlas ICBM, despite having wings, a cockpit,
landing gear, non-integral non-pressure rigidized propellant tanks, and
a TPS on it.
That is one of the silliest things I've ever seen in my life, and why
people ever took it seriously for even a moment is completely beyond me,
particularly given its kerosene-hydrogen peroxide choice of propellants,
which hearkens back to the 1950s.

It was somewhat silly, but not laughably silly like Mook's napkin
drawings.

Jeff
--
The only decision you'll have to make is
Who goes in after the snake in the morning?

In article 7e7188c0-1901-4d12-93f1-
, says...

On Sep 24, 2:04*pm, Jeff Findley wrote:
From memory, the landing gear couldn't retract without
disconnecting and reconnecting the hoses used for lowering the landing
gear. *Before the final flight, someone forgot to reconnect a hose, so
one of the gear failed to deploy.

Yes. Some thought sabotage at the time,

Only loony conspiracy theorists.

He's comparing apples and oranges since the DC-X is
so different than what he's proposing.

Nonsense. If you actually looked at the numbers, you would see that
the empty weight of the DC-X divided by its surface area is very low
as well.

Apples and oranges. DC-X had no wings, and you said yourself it wasn't
"flight weight".

*Those wings are just silly in
the way they're designed and in the way they're planned to be used.

No they're not.

More repeated assertions backed up by a cursory, high level, parametric
based design. In other words, a napkin drawing.

And you're trying to demean a real engineer who has something
spectacular playing word games without one iota of real engineering
analysis.

And you're trying to present yourself as a "real engineer". So, you're
a certified P.E. now? You do know that asserting you're a "real
engineer" without a P.E. is a very dangerous thing to do in many states.

Jeffie, you and Freddie can stroke each other all you want. It won't
make up for the absolute lack of real analysis to support any of your
bogus objections.

You're the one with the "design" that needs to be backed up by real
analysis and design. Your napkin drawing doesn't count.

I'm a supporter of getting NASA out of the launch vehicle business.
There are more than enough US launch providers in existence today. The
US certainly doesn't need anything as big and expensive as you're
proposing. Heck, NASA couldn't' even afford to finish Ares I, let alone
Ares V, or anything bigger than that.

Jeff
--
The only decision you'll have to make is
Who goes in after the snake in the morning?

On 9/27/2010 1:51 AM, Sylvia Else wrote:


In fact, the ideal situation for them is if the program gets canceled
before flying; then you can design something that you know can't work,
get paid for working on it, and know that it well never be finished...so
you won't get sued for defrauding the US government.

Pat

Sounds like a good incentive for dragging it out as long as possible,
especially if it's meant to be man-rated.

Which may explain why SpaceX could get their Falcon 9/Dragon capsule
combo ready so much faster than NASA could do Ares 1/Orion.
The excuse the aerospace industry uses is that by dragging the program
out over many years, they cut down the cost per year.
What they don't mention is that by doing it this way, the total cost is
far greater when everything's finished, as now you are keeping all the
companies working on it overhead's paid for many years for something
that you could have built a lot faster if you had really needed to.
The way they do things nowadays, we would have had the B-29 in full
production around 1955. ;-)

Pat

On Sep 27, 8:54*am, Jeff Findley wrote:
In article SeKdnSrsFsZS8ADRnZ2dnUVZ_j-
, says...





On 9/24/2010 6:47 AM, Jeff Findley wrote:

True, but then you wouldn't need the inflatable heat shield for the nose
of the ET, so that's not nearly complicated enough for Mook.

There is no need to put a heatshield on the nose; the plug nozzle engine
on the tail is heavy enough to make it fall into the atmosphere pretty
much tail-first anyway, and is already made out of heat resistant
materials to take the heat of the rocket exhaust.
Back when Philip Bono was coming up with the SSTO plug-nozzle engine
designs for Martin Aerospace like the Pegasus and Ithacus, reentry was
to be handled by ejecting some leftover LH2 from the center of the
bottom of the central plug and letting the cold gas form a sheath over
the bottom of the plug to prevent heating damage during reentry.
That's what's going on in this painting of a Pegasus reentering:
http://www.astronautix.com/graphics/p/pegasus2.jpg

Tell that to Mook. *He's the one arguing for an inflatable nose heat
shield, not me.

Jeff
--
The only decision you'll have to make is
Who goes in after the snake in the morning?

I've already responded to that one. I grew up on Bono's designs. I
love the Hyperion and the other big launchers. So, I looked at doing
just what he did.

When you look into it you find the ET airframe isn't the Hyperion
airframe. The ET is longer and narrower, and the CG is more forward
than in the Hyperion. Even with an aerospike engine on the tail, the
CG is farther forward. Also, I'm using the ET as a common element in
a multi-element (multi-stage) launcher. The booster elements do not
attain orbit, and so, suffer significant air drag forces when pitched
over. The added weight of structure and thermal protection needed to
allow this is greater than just adding an inflatable heat shield on
the nose and letting it fly foward without any radical pitching
maneuver.

Then, when the element slows to subsonic speed - terminal velocity -
fold away wings and tail deploy, and the system becomes a glider.
This is when it is snagged by a B-737 rigged as a tow plane, to tow it
back to the launch center. There it is released at a controlled
altitude, and the unit glides toward a mobile landing platform. It
ignites a landing engine, climbs into vertical nose up (which is
modest at subsonic speeds, not at all like hypersonic pitching) and
descends on its landing engine like the DC-X of the 90s - or tail
sitting aircraft of the 50s and 60s. The mobile platform remains
centered under the descending spacecraft and activates hold down
clamps when seated in the platform. The landing engine is switched
off and the mobile platform takes the element in for processing for
the next launch.

On Sep 27, 8:55*am, Jeff Findley wrote:
In article
tatelephone,
says...



In articlefcbfe968-0bb0-46ce-a6bf-f5611a8d94d4
@l32g2000prn.googlegroups.com, says...

Yet, none were lost this way.

No, that's how the SNECMA Coleoptere was lost; they tried to to do a
vertical takeoff and landing in it, and it started tumbling over
sideways as it descended. The pilot ejected, and the out of control
aircraft ended up going almost horizontal before slamming into the
ground and exploding.
And that was the last you heard of the Coleoptere; the French canceled
it and never talked about it again. :-D

You'll confuse Mook with facts like this.


Jeff, you are confused if you think the SNECMA Coleoptere experience
is relevant to what I'm doing.

r_XFY

I'm using a regular wing, not a crazy design like the Coleoptere. To
compare what I'm doing with the Coleoptere and ignore the excellent
experience of other tail sitting aircraft is just plain stupid.

Bottom line, the Coleopter has no wings - or rather an annular wing.
The issues they had with the aircraft had to do with the wing they
used, not with the fact it was a tail sitter

Check it out - here's the Coleopter

http://en.wikipedia.org/wiki/Coleopter

Now compare it to the more successful tail sitting aircraft

http://en.wikipedia.org/wiki/X-13_Vertijet
http://en.wikipedia.org/wiki/Convai

In his mind, his napkin
drawing is absolutely perfect.

The dimensioned prints I've published are not napkin drawings, and
I've never said they were perfect. Despite that, nothing you or any
of the other detractors that have emerged here on usenet have said
anything negative that stands the light of day about it.

http://www.scribd.com/doc/31261680/Etdhlrlv-Addendum
http://www.scribd.com/doc/30943696/ETDHLRLV
http://www.scribd.com/doc/35439593/S...-Satellite-GEO




Jeff
--
The only decision you'll have to make is
Who goes in after the snake in the morning?