I got my L1 cert at the October skies, TCC launch last weekend, and I
am worried about the fate of amateur rocketry from current trends in
overzealous regulation. I am at a point where I haven't yet invested
in too much motor hardware and I am wondering if I should just make the
switch to hybrid now to avoid this misguided overregulation by the ATF.
I don't live in a place where an LEUP is possible and it seems that
going hybrid is a reasonable alternative. I didn't have a lot of time
to wander around at the launch, but I didn't hear of anyone using
hybrid. Are any of you using hybrid? Why is it not more accepted by
the HPR community as a whole?
All of my HP flights are hybrid flights, not so much because of the
regulatory picture as the "quirky complexity" of hybrids in general. There
is a steep cost and learning curve with hybrids, and I think this deters a
lot of folks from becoming involved. Also, each flight requires electronic
deployment, so added expense, prep time, and complexity.
There are also some realities working with hybrids: the motor case are LONG,
and require rockets that can handle them (I scratch build everything, except
a Flis Richter Recker that I'm bashing for 29mm hybrids). The mass fraction
is not as favorable as APCP, nor is the ISP as high. They are, however,
capable of some decent performance, especially the newer crop of monotube
I posted a blurb in alt.binaries.models.rockets about the cost of GSE and
the cost per flight. The conclusion I've come to is that if you are going to
fly a lot, hybrids are not only cost effective but cheaper than AP motors,
though it takes a while to 'break even' on the GSE. The cost, however, was
not a prime issue for me... a couple years back when I BAR I was surfing the
web when I came across a video of a hybrid rocket on the pad, filling and
then venting before launch... I was hooked! It's only gotten worse since
then, and both clustered and staged hybrids are on my slate for next summer.
Why are hybrids not more accepted? Cost, complexity, and a steep learning
curve are factors. Very few dealers support hybrid products. A perception
that hybrid motors are "wimpy". Few experienced gas-passers to mentor new
hybrid flyers. I think it's the complexity that puts most people off; I
frequently hear comments like "I could prep and fly four rockets in the time
it takes you to prep one." Although more and more lately I'm hearing "THAT
was a hybrid?!?!?" LOL-- I chalk that up to my increasing experience and the
J642 motor I recently launched :)
After I wrote this, I set up an excel spreadsheet that broke down the costs
per flight of the hybrid motors I've flown, the cost of a (generally)
comparable AP reload, and the number of flights I made this year. To my
surprise I appear to have saved $475 over 31 flights....
Reinforces what I thought was true, that enough flights makes owning the GSE
(cost ~$600) worth it. "Enough" is fewer than I thought, however... I was
thinking on the order of 100 flights.
The cost difference scales with the motor size. M motor hybrids can
save $100 or more per flight (not including GSE amortization).
To me hybrids are just another aspect of the hobby that I enjoy. I fly
both APCP and Hybrids.
Kev> After I wrote this, I set up an excel spreadsheet that broke down the
For hybrids or a LEUP, I suggest that you check with your club to see
what resources are available. By that I mean see if someone is
willing to provide contingency storage and see if they have GSE. Once
you've checked into it, go from there.
Our club has a full GSE but due to it's age, we've had a lot of failed
launches which turned people off to the idea of Hybrids.. that seems
to be the norm in the past if they've had them and things have gotten
much easier nowadays.. Doug Pratt from Pratthobbies
seems to be the go-2-guy when it comes to the
in's and out's of hybrids for any specific questions.. I'm currently
picking up a RATT works setup to get everything working.. To have the
casings for H/I be only $60-$90 and the reloads be $25 for a 3 pack is
a very nice option.. Talk to your local club about getting a GSE to
keep it's membership going because after this past week, we're going to
have a very very slow 8+ months and nothing states that he's going to
make a decision at that time anyways.. PS. Both Tripoli and NAR allow
people to launch level 1 on the Rattworks H70.. 29mm x 18" long..
only downside is that you're basicly required to get some kind of
electronics since hybrids don't have motor ejection..
How many pink pickup trucks do you see on the highway? Not many, because a
Real man wouldn't be caught dead in a pink pickup. Rocketry is the same in a
lot of ways.
- hybrids don't "sound" like a real rocket motor
- no colored smoke
On a ROL forum, Gary from Aerotech once commented that high power rocketry
isn't about ISP. It's good that he understands his market.
Sometimes it seems like model rocketry is glorified fireworks.
While I agree that the BATFE thing is crazy and I can't wait to be able
to not have an LEUP, comparing Hybrids with a Pink Pickup Truck is
pretty bad.. saying that they don't have colored smoke and the fact
that the "sound" is different is pretty bad on your part.. They do
have sparky motors and depending on the fuel material, you can get
either Black or White smoke.. ooohh.. so I don't have Red, Blue or
Purple.. what a loss? Tell the guys that built the "Hybrid" Space
Ship One that they won the X-Prize in a pink pickup truck and see the
reaction you'll get..
The guys who built SS1 cared about ISP and didn't care about a macho sound or
colored smoke. They weren't flying HPR, they were flying a commercial rocket.
There _is_ a difference.
You can say it's "bad", but I call the shots as I see the attitudes on the
launch field and on RMR.
I don't care what the color of your rocket's smoke is, or what color you
painted it, or if your paint has runs in it. I'm a miniority in that aspect.
I see more people oogling about red flame or black smoke than about the
impulse of a motor. Why does Aerotech offer a wide varieties of _color_
instead of thrust level / burn time, etc? I mean, what's great about a
Readline motor other than the red colored flame? Why do people fly sparky
motors, when all the sparking material does is rob the motor of performance?
I've also discovered that to most fliers the paint job of the rocket is more
important than how it flies. Go to a launch with a bucket full of unpainted
rockets and see how many people give you crap about it. I used to, and even
though I now do a paint job of some sort on all my rockets, I still have a
reputation of flying unpainted rockets.
What do you think the startup cost will be for some H and I impulse
flights? Also, I intend to take this hybrid to level 2 or 3
eventually, so do I need different launch support for each level. By
launch support I am talking tanks, regulators, ignition source etc? Is
there a good tutorial on the subject? Also, other than longer motor
tube, what other considerations are necessary for rocket construction?
I appreciate Glen's comments because I did ask why hybrids weren't more
common in the rocketry groups. And Glen's answer actually is
encouraging since I thought there might be valid concerns, but if the
only problem is that they don't make enough noise or smoke
place to start.
As with APCP, different motors have different properties. The WestCoast
I110 has a nice blend of smoke and noise. The RATTworks K240 has a
unique sound and visuals. As do the Hyperteks.
Tanks and regulators are the same for everything. Pratthobbies.com
has a modular system that can be modified and expanded to work with
most hybrid systems. Doug Pratt is a great source of knowledge and
products for hybrids.
Hybrids are a lot of fun. But you can't do motor based ejection
systems. So you have to use electronics. And that means (for most
people) ematches and BP. Doug Pratt has nichrome based canisters that
avoid the e-match issue. But you still need BP or Pyrodex and you are
supposed to have a LEUP to use either in a hobby rocket.