HTO rocket concept

Doug Goncz wrote:

For an HTOL space plane with a reentry body generating some lift, and
necessarily equipped with wheels for HL, can the HTO under rocket power be
augmented by picking up some liquid from a trench in the runway, and pumping
this liquid into the combustion chamber for vaporization, cooling the exhaust
but adding mass flow?

Kind of like in-flight refueling along a running start. Liquid could be
peroxide or water, or maybe something else. With three wheels, the possibility
of two trenches is obvious, and of course might support a fuel and an oxidizer.
Switching from that to the onboard fuel supply could be pretty tricky.

I got this idea from the water trench that slows the rocket sled used for
various on-ground tests at high speed. If one picked up water from that trench
at speedd and vaporized it inside the rocket that drives the sled, increased
thrust might be realized. The forward motion itself would pressurize the water
to some degree, like a liquid-in / vapor-out ramjet....

And in addition to the fact that the liquid consists of flammable
cryogenic or hydrocarbon liquid in an open trench just waiting for any
spark, it's going to have that *same* slowing effect as a water trench
does. The engines would have to work harder, just to break even.

You'd be better off with mid-air refueling....

Doug Goncz wrote:

For an HTOL space plane with a reentry body generating some lift, and
necessarily equipped with wheels for HL, can the HTO under rocket power be
augmented by picking up some liquid from a trench in the runway, and pumping
this liquid into the combustion chamber for vaporization, cooling the exhaust
but adding mass flow?

Kind of like in-flight refueling along a running start. Liquid could be
peroxide or water, or maybe something else. With three wheels, the possibility
of two trenches is obvious, and of course might support a fuel and an oxidizer.
Switching from that to the onboard fuel supply could be pretty tricky.

I got this idea from the water trench that slows the rocket sled used for
various on-ground tests at high speed. If one picked up water from that trench
at speedd and vaporized it inside the rocket that drives the sled, increased
thrust might be realized. The forward motion itself would pressurize the water
to some degree, like a liquid-in / vapor-out ramjet....

Yours,

Doug Goncz, Replikon Research, Seven Corners, VA
Unequal distribution of apoptotic factors regulates
embryonic neuronal stem cell proliferation


a rocket powered catapult?

Doug Goncz wrote:

For an HTOL space plane with a reentry body generating some lift, and
necessarily equipped with wheels for HL, can the HTO under rocket power be
augmented by picking up some liquid from a trench in the runway, and
pumping this liquid into the combustion chamber for vaporization, cooling
the exhaust but adding mass flow?

Kind of like in-flight refueling along a running start. Liquid could be
peroxide or water, or maybe something else. With three wheels, the
possibility of two trenches is obvious, and of course might support a fuel
and an oxidizer. Switching from that to the onboard fuel supply could be
pretty tricky.

I got this idea from the water trench that slows the rocket sled used for
various on-ground tests at high speed. If one picked up water from that
trench at speedd and vaporized it inside the rocket that drives the sled,
increased thrust might be realized. The forward motion itself would
pressurize the water to some degree, like a liquid-in / vapor-out
ramjet....



Hi, Doug

The Ocean is the longest runway in the world. May as well use if to takeoff
too.

Craig Fink

" Doug Goncz " wrote;
For an HTOL space plane with a reentry body generating some lift, and
necessarily equipped with wheels for HL, can the HTO under rocket power be
augmented by picking up some liquid from a trench in the runway, and
pumping
this liquid into the combustion chamber for vaporization, cooling the
exhaust
but adding mass flow?

Briefly, yes, it could. But it strikes me that the engineering difficulties
of ensuring that the liquid take-up devices suck only liquid, not air during
the launch process (think of the spray, the wake behind a fast moving boat!)
make me shudder. A simpler solution was bandied around for the original
HoToL concept.
If the sole intent is to get the vehicle to take-off speed with essentially
no fuel penalty for the vehicle, then it is simpler to sit the vehicle on a
rocket-or-jet-powered trolley/sledge.

Note, nit-pickers may calls this a TSTO.

Other HL craft I've toyed with for various European aero corporations simply
ignored the how-to-get-it-airborne question, as the first 100 m/s are
relatively trivial compared to the other 8 km/s or so. Especially as the
technology for getting things moving quickly at ground level is
well-developed (see above).

-James Garry

Doug:
For an HTOL space plane with a reentry body generating some lift, and
necessarily equipped with wheels for HL, can the HTO under rocket power
be augmented by picking up some liquid from a trench in the runway, and
pumping this liquid into the combustion chamber for vaporization, cooling
the exhaust but adding mass flow?

The simple answer is yes, but since you are considering initial acceleration
supported by the ground, weight is less of an issue. For safety only consider
water.

A fairly steep incline is preferred. The carriage would have to distribute
support of the vehicle and would be the zero-stage booster. Pressure-fed
rockets are preferred due to the ridged tanks needed to support the vehicle.
Water would be useful to dampen noise to protect the hardware. A fair
site should get you started 3 km up and already at 90 m/s.
A WAG on size/type:
Three people plus 1000 kg LEO in a two stage to orbit lifting body.

Look into tender concepts used on the T1 (steam locomotive). They would
scoop make-up water from special flood troughs built along their route
(East coast express routes). Some air-drop tanker planes also scoup water
from lakes (at a good speed) fighting forest fires.
--
Anvil*

Lots of good responses!

Thanks to all.

Must...not...assume...engineers...have never tried...this idea...

My Kirk imitation

----------------

Hi, Doug

The Ocean is the longest runway in the world. May as well use if to takeoff
too.

Craig Fink

-----------------------

I used to use this in my sig! Glad to hear someone else has the same vision.
What about the salt deposits as the water is evaporated?

I read the specs on the Space Shuttle and the SSME trio is "only" moving about
40 gallons per second of water equivalent mass of H2 / O2, but it's not the
stoich mix, it's high in H2.

I guess that yes, the amount of energy expended in getting started is small
compared to the huge energy required to speed upwards to orbit.

I had read somewhere that passenger jets use most of their fuel taking off.
Maybe I misread it and they use most of their fuel taking off AND climbing to
the clean, cold air at cruise altitude, and accelerating to cruise speed. That
would make sense.

Thanks all.



Yours,

Doug Goncz, Replikon Research, Seven Corners, VA
Unequal distribution of apoptotic factors regulates
embryonic neuronal stem cell proliferation