Shuttle Derived Launchers - Safe, Simple, Soon

John wrote:
In article ,
Jorge R. Frank wrote:
Well, except for the ET. The current ET is designed to absorb loads along
the side through the intertank (orbiter and SRB forward attach points) and
the aft ring (orbiter and SRB aft attach points).

One possible heavy-lift configuration I've never seen proposed is two
ET+SRBs mounted to a single central carrier. Pardon the ASCII-art,
but if you were to take a horizontal cross section, it would look like:

o o
()O()
o o

Whe
o = SRB
() = ET
O = central carrier

This way, the ETs would take thrust loads similar to what they take now.
It seems that that would get you up to around 320-350 Klb payloads with
much less re-engineering.

The central carrier *could* be winged for flyback and reuse. It could
even keep one of the ETs attached during part of reentry to lower the
density and take the bulk of the heating loads.

There is one shuttle-derived concept floating around
that is claimed to be able to put 850 Klbs into low
earth orbit or 340 Klbs on a translunar trajectory.
It is an ET core (LOX/RP) with six RD-180s, boosted
by six RSRMs, topped by an ET-based LOX/LH2 second
stage powered by three SSMEs. It looks like a
Delta 2, except 450 feet tall with a 28 foot diameter
core! The thing would weigh 14.4 million pounds at
liftoff and would create 21 million pounds of liftoff
thrust. Its name is MAX (Mars Express).

- Ed Kyle

In article .com,
"Ed Kyle" wrote:

John wrote:
In article ,
Jorge R. Frank wrote:
Well, except for the ET. The current ET is designed to absorb loads along
the side through the intertank (orbiter and SRB forward attach points) and
the aft ring (orbiter and SRB aft attach points).

One possible heavy-lift configuration I've never seen proposed is two
ET+SRBs mounted to a single central carrier. Pardon the ASCII-art,
but if you were to take a horizontal cross section, it would look like:

o o
()O()
o o

Whe
o = SRB
() = ET
O = central carrier

This way, the ETs would take thrust loads similar to what they take now.
It seems that that would get you up to around 320-350 Klb payloads with
much less re-engineering.

The central carrier *could* be winged for flyback and reuse. It could
even keep one of the ETs attached during part of reentry to lower the
density and take the bulk of the heating loads.

There is one shuttle-derived concept floating around
that is claimed to be able to put 850 Klbs into low
earth orbit or 340 Klbs on a translunar trajectory.
It is an ET core (LOX/RP) with six RD-180s, boosted
by six RSRMs, topped by an ET-based LOX/LH2 second
stage powered by three SSMEs. It looks like a
Delta 2, except 450 feet tall with a 28 foot diameter
core! The thing would weigh 14.4 million pounds at
liftoff and would create 21 million pounds of liftoff
thrust. Its name is MAX (Mars Express).

- Ed Kyle

At what point do we just say 'enough'? If this thing ever got built, and
heaven forbid fell back onto the pad, the resulting explosion would make
the N1 debacle look like a firecracker.

P

"Ed Kyle" wrote in message
oups.com...
John wrote:
In article ,
Jorge R. Frank wrote:
Well, except for the ET. The current ET is designed to absorb loads
along
the side through the intertank (orbiter and SRB forward attach points)
and
the aft ring (orbiter and SRB aft attach points).

One possible heavy-lift configuration I've never seen proposed is two
ET+SRBs mounted to a single central carrier. Pardon the ASCII-art,
but if you were to take a horizontal cross section, it would look like:

o o
()O()
o o

Whe
o = SRB
() = ET
O = central carrier

This way, the ETs would take thrust loads similar to what they take now.
It seems that that would get you up to around 320-350 Klb payloads with
much less re-engineering.

The central carrier *could* be winged for flyback and reuse. It could
even keep one of the ETs attached during part of reentry to lower the
density and take the bulk of the heating loads.

There is one shuttle-derived concept floating around
that is claimed to be able to put 850 Klbs into low
earth orbit or 340 Klbs on a translunar trajectory.
It is an ET core (LOX/RP) with six RD-180s, boosted
by six RSRMs, topped by an ET-based LOX/LH2 second
stage powered by three SSMEs. It looks like a
Delta 2, except 450 feet tall with a 28 foot diameter
core! The thing would weigh 14.4 million pounds at
liftoff and would create 21 million pounds of liftoff
thrust. Its name is MAX (Mars Express).

- Ed Kyle


That's an implausible figure for payload, since it's about 6% of the takeoff
weight. The Atlas III was rated at about 4.7%, and it wasn't burdened with
the low performance SRBs. I'd say about 600 000 lbs max to LEO (just over
4%) and 240 000 translunar.

Murray Anderson

Murray Anderson wrote:
"Ed Kyle" wrote in message

There is one shuttle-derived concept floating around
that is claimed to be able to put 850 Klbs into low
earth orbit or 340 Klbs on a translunar trajectory.
It is an ET core (LOX/RP) with six RD-180s, boosted
by six RSRMs, topped by an ET-based LOX/LH2 second
stage powered by three SSMEs. It looks like a
Delta 2, except 450 feet tall with a 28 foot diameter
core! The thing would weigh 14.4 million pounds at
liftoff and would create 21 million pounds of liftoff
thrust. Its name is MAX (Mars Express).


That's an implausible figure for payload, since it's about 6% of the takeoff
weight. The Atlas III was rated at about 4.7%, and it wasn't burdened with
the low performance SRBs. I'd say about 600 000 lbs max to LEO (just over
4%) and 240 000 translunar.

The 6% figure does seem interestingly similar to the
6% shuttle stack mass (orbiter and payload) that can be
orbited - but this includes SSMEs and other hardware
that traditionally would not be considered "payload".

- Ed Kyle

"John" wrote in message
...
In article ,
Jorge R. Frank wrote:
Well, except for the ET. The current ET is designed to absorb loads
along
the side through the intertank (orbiter and SRB forward attach points)
and
the aft ring (orbiter and SRB aft attach points).

One possible heavy-lift configuration I've never seen proposed is two
ET+SRBs mounted to a single central carrier. Pardon the ASCII-art,
but if you were to take a horizontal cross section, it would look like:

o o
()O()
o o

Whe
o = SRB
() = ET
O = central carrier

This way, the ETs would take thrust loads similar to what they take now.
It seems that that would get you up to around 320-350 Klb payloads with
much less re-engineering.

Except for the fact that such a beast would very likely be far too big to be
moved by the current MLP's (nevermind that they don't have "holes" in the
right places for the exhaust thrust). Also, I seriously doubt if the
crawler transporters could support the weight of four SRB's and two ET's,
nevermind the weight of the "central carrier" that would likey sport four to
six SSME's (i.e. two times what a "shuttle C" would use".

The central carrier *could* be winged for flyback and reuse.

Sounds like this would be a 2X size space shuttle. Exactly how would this
be better than the current shuttle?

It could
even keep one of the ETs attached during part of reentry to lower the
density and take the bulk of the heating loads.

ET's aren't designed to "take the bulk of the heating loads" and remain
structurally intact. They're designed to break up upon reentry. I think
this would take quite a bit of changes to make such a scheme work.

Jeff
--
Remove icky phrase from email address to get a valid address.

"Murray Anderson" wrote in message
...

"Ed Kyle" wrote in message
oups.com...
There is one shuttle-derived concept floating around
that is claimed to be able to put 850 Klbs into low
earth orbit or 340 Klbs on a translunar trajectory.
It is an ET core (LOX/RP) with six RD-180s, boosted
by six RSRMs, topped by an ET-based LOX/LH2 second
stage powered by three SSMEs. It looks like a
Delta 2, except 450 feet tall with a 28 foot diameter
core! The thing would weigh 14.4 million pounds at
liftoff and would create 21 million pounds of liftoff
thrust. Its name is MAX (Mars Express).

That's an implausible figure for payload, since it's about 6% of the
takeoff
weight. The Atlas III was rated at about 4.7%, and it wasn't burdened with
the low performance SRBs. I'd say about 600 000 lbs max to LEO (just over
4%) and 240 000 translunar.

Why is that implausible when you consider the ISP of the RD-180's and the
ISP of the SSME's (you could even extend the SSME nozzles for a bit more
vacuum ISP).

In other words, a BOTE calculation based on % payload mass likely isn't
detailed enough.

Jeff
--
Remove icky phrase from email address to get a valid address.

Phil Bagust wrote:

At what point do we just say 'enough'? If this thing ever got built, and
heaven forbid fell back onto the pad, the resulting explosion would make
the N1 debacle look like a firecracker.


I'd still like to see one of these blow up on the pad:
http://www.astronautix.com/lvs/ur900.htm

Pat

"Jeff Findley" wrote in message
...

"Murray Anderson" wrote in message
...

"Ed Kyle" wrote in message
oups.com...
There is one shuttle-derived concept floating around
that is claimed to be able to put 850 Klbs into low
earth orbit or 340 Klbs on a translunar trajectory.
It is an ET core (LOX/RP) with six RD-180s, boosted
by six RSRMs, topped by an ET-based LOX/LH2 second
stage powered by three SSMEs. It looks like a
Delta 2, except 450 feet tall with a 28 foot diameter
core! The thing would weigh 14.4 million pounds at
liftoff and would create 21 million pounds of liftoff
thrust. Its name is MAX (Mars Express).

That's an implausible figure for payload, since it's about 6% of the
takeoff
weight. The Atlas III was rated at about 4.7%, and it wasn't burdened
with
the low performance SRBs. I'd say about 600 000 lbs max to LEO (just
over
4%) and 240 000 translunar.

Why is that implausible when you consider the ISP of the RD-180's and the
ISP of the SSME's (you could even extend the SSME nozzles for a bit more
vacuum ISP).

In other words, a BOTE calculation based on % payload mass likely isn't
detailed enough.

Jeff
--
Remove icky phrase from email address to get a valid address.



The proposed Atlas V upgrade to a larger Centaur gives 26.6 tons payload to
a 100 nm orbit. The liftoff weight would be about 600 tons, including 225
tons solids, 305 tons core stage, and 65 tons upper stage plus payload.
That's about 4.5% and includes more RD-180 in relation to solids than the
proposed configuration. See the Atlas mission planner guide, section 8, page
9.
Maybe 4% is a little low - but 6% is unreasonable.

Murray Anderson

Griffin wrote a text just a few years ago suggesting using shuttle
derived hardware for the moon-mars goal. I think I remember seeing the
article in an IAAA journal.

Gene

"Jeff Findley" wrote in message
...
Sounds like this would be a 2X size space shuttle. Exactly how would this
be better than the current shuttle?

You could blow up twice as much stuff.