Showing posts with label Hybrid. Show all posts
Showing posts with label Hybrid. Show all posts

Thursday, June 18, 2009

Shuttle Kvetch



Two possible versions of Shuttle-C.

Anyone who knows me, or who's read this blog, should
know that I love anything that flies, from paper
airplanes and match rockets to the Voyager probes
currently coasting in intersellar space.
I don't hate NASA, or the Shuttle. As those of us who
know anything about it know, the blame isn't all on
NASA's shoulders. For the sake of brevity [too late]
NASA will do for now.
Part of this first rant is going to spill onto the
International Space Station as well. More on the ISS
in the next installment.

I am mad at NASA for the way they screwed up the
shuttle program nearly every step of the way, until
it's admittedly too late to do anything about it.
What angers me most is that it's an obviously modular
system, and yet this is the most underutilized
feature of the system.

Ok class... who here knows that the original strap-on
boosters were supposed to be hybrid motors?
Huh, what happened? I admit I'm a hybrid proponent,
bigtime, but that floored me when I found out.
Hybrid motors are great because they are a lot simpler
and cheaper than liquid fuel boosters, and broadly
speaking, a LOT safer than liquid OR solid boosters. A
hybrid is vastly simplier than a bi-liquid system and
doesn't carry all that liquid kerosene or hydrogen that
makes such a pretty fireball. While a hybrid is more
complicated and heavier than an all solid rocket motor,
it's still safer because, if there's a problem, you can
shut them off.
Unfortumately, Hybrid tech was still very immature at
the time, it would still be a few years before AMROC
tested their big ones, and those weren't big enough.
However, there was no reason the shuttle couldn't fly
on solids initially, while Hybrid R&D was fast tracked.
Modular remember? The Hybrid strap-on boosters might've
been flying in time to avert the Challenger disaster.

After Challenger, NASA and Rockwell put heads together
and decided what improvements to make before building
a replacement orbiter. Bravo!
Of course having a large inventory of huge orbiter
components in storage helped speed construction. Endeavor
really is a B model orbiter. The other 3 orbiters received
the same upgrades wherever possible. After Endeavor flew,
and the fleet upgrades were finished, they should've sat
down AGAIN and planned an even better orbiter. Not just a
Challenger replacement, or 2nd Endeavor, but an eventual
fleet replacement, or supplement. Maybe a real departure
from the earlier orbiters, certainly more maintainable.
Modular!! As these new orbiters came on line, the older
units could be retired to museums. Read COLUMBIA!!!
If NASA had done this, the fleet would still be modern,
if not cutting edge, today. Hell, this still could've
[should've] been done when the SSTO initiative fell through.

At some time NASA had plans for Shuttle C. This would've
been an unmanned wingless cargo version. Little more than
a cargo bay with motors and guidance. Three reasons for
building it were to be able to fly heavier or larger loads
when needed, like station segments, and to reduce man hours
in space when not needed. Third would be hazardous payloads.
After Challenger, liquid fueled payload boosters were
outlawed for the shuttle for crew safety reasons, reducing
the types of missions STS could support.
Using Shuttle-C, station segments would be released in orbit
near the station, then crews would retrieve them for
assembly. Before the station was manned, they would've placed
2-3 modules in orbit, then sent up a manned orbiter, with
supplies and other components, to do assembly. Of course,
today the segments might be docked autonomously.
I always thought you could make even bigger station segments,
and attach the guidance/thruster package, and motor pack to
the segment couplers at each end, then fly it in place of an
orbiter. The flight components would be removed and saved,
eventually flying home in an orbiter cargo bay for reuse.
Of course either scenario assumes you want the STS system
involved in boosting the major station components anyway.
Read Saturn!!
The shuttle bay is dinky compared to a Skylab, and Skylab
was no strain on the Saturn V. I do not advocate resurrecting
the Saturns after all this time, they really are dinosaurs now.
I am saying we should never have fully retired them.
Incremental improvements have kept Atlas, Delta and Titan in
the air longer than Saturn's been on paper.

Plenty of folks like to second guess NASA and I'm genuinely
sorry to be lumped in with them. However I've had these opinions
for years, and even shared them with a few NASA engineers, who
happened to agree. Not just because I'm a size 2 1/2 biker
maniac either. It feels good to finally write and post this.


I'm sure this post could still use more editing, but if I held
onto it any longer it would turn into a book.



Wednesday, April 29, 2009

The Barking Pumpkin



 

Ace was a kit [plus occasional motors] manufacturer from
sometime in the '70's through the '80's. Ace was owned by
Korey Kline who is better known these days for pioneering
the Hypertek hobby hybrid motors and the Hyperion hybrid
sounding rocket flights at Wallops Island.

The ACE 4" 4:1 nose cone was the first plastic hipower nose
cone available, and has been used by many kit makers and
custom builders, and is doubtless still being produced.

The Ace Sonic, of course, uses 2 of these cones to make a
very streamlined 4" rocket under 3 feet long. The stock kit
had a 29mm motor mount, I built mine with a 38mm motor
mount so it's a bit shorter, and a lot faster. It also means that
it has a tendency to whip a 1/4" launch rod hard, then
thunder off on a random vector. What Fun!! 

Over the years I've' flown it on exotics and extremes like;
G210, G300, H242, I250, I357 and G160 & H220 black
powder Silver Streaks as shown above, plus many others.
In order to accomodate the longer motors, the motor mount
tube extends up to the back of the nose cone. The recovery
system packs around it.

Due to it's compact yet visible design it has traveled to [and
returned from] more flying sites than any other single hi-pwr
rocket I own. This includes 2 trips in private aircraft and twice
on my motorcycle. I'm pleased to say that it's rod whipping
days are over. It took a wee bit of enginuity, but it's now
equiped with rail buttons instead of a lug. The front button is
attached to the nosecone just above the shoulder, the rear is
at the bottom of the parachute well, half way down the
airframe, with a standoff.  It would've been nice to keep the
launch lug for versatility, but low-drag philosophy will out.