Liquid Fuel Engines A and up...

Larry S. wrote:

Single tank version:

You'd need to fill the liquid (noncompressible) fuel first; the sleeve on the piston stops it at the right point. Then fill the O2 to the right pressure.

What you still need to design is the valves. I'm thinking, a clip-on valve like they use for hydraulics. Clip on the fill adapter, fill, remove it and it seals. Clip on a disposable launch nozzle with combustible baffles over each feed line. Insert igniter, launch - it burns off the baffles, which opens the flow of fuel and O2 and ignites them, and off you go!

But you'd never be able to avoid TRA or NAR. The NFPA rules they "abide" by are about solid propellants only.

If the seal failed even a little you'd have traces of fuel in contact with high-pressure gaseous O2 inside the tank. Disaster time.

Even lox is much safer than high-pressure gox in contact with fuel traces.

If only NAR and TRA wold simply adjust to the law.

Oh well.

Jerry

C'mon, Jerry. Liquid motors are more complex on the order of about a bazillion, from hardware to GSE to whatever. Look at it this way, pop a cork on an APCP motor and you can get a pretty big mess (but usually pretty contained). Pop a cork on a liquid motor... big difference I think...

Yeah, I'd say KISS was perhaps a bit more complicated than a similar sized hybrid-based HPR, but not extremely so. (We tried to keep it HPR-like and as simple as possible... hence we named it after the common army acronym. "Which is the simpler way?" was a frequent decision driver.)

-dave w

So was this post an ACTUAL kiss Dave?

:)

Well, once the Phil & Fred & Foxeye foam-frog-orgy got going, and they started making misguided innuendoes like they did, I certainly thought our rocket name was amusing in ironic retrospect!!

-dave w

Please explain how liquid fueled rockets can be considered nearly as safe as solid fuel. I've seen solid fuel rockets crash under power and even when they hit hard enough to eject propellent, it was just small burning chunks. CATOs are even less spectacular -- often the propellent self-extinguishes. No offense, but I find it hard to believe that a liquid fueled rocket would behave in a similar manner in the event of a CATO or power prang, but maybe I'm missing something. If you or Dave could enlighten me, I'd appreciate it.

Both types of rockets share the same pad hazard. Blast radius.

They share the same launch hazards, land shark and ballistic impact.

The Blast radius of a liquid is not different from a solid which typicically operates at a HIGHER pressure or a hybrid (yes they do blow agressively at times).

A liquid has SEPARATE oxidizer and fuel tanks.

The main problem of course is Tripoli (and NAR) writes offset distances for the modal impact distance, not the blast safety distance. So ANY new style of rocket would ADD TO OVERALL HAZARD.

Jerry

Funny how you have intellectual irony and all they have is frothing about the mouth. I suppose it lubes their experiences with each other :)

Jerry

Hurry, Hurry, hurry, find your bridge, get under it quick..

Fred

Speaking your language Fred.

"dances on graves"

You seemed to agree that there were a lot of 'safety issues' with hobby liquids when you posted in agreement to a thread that Chuck posted in a while back.

LOL! Great minds think alike. :-)

cp

I refer to my parsed reply.

I like it.

Is this so at the pressures we are talking about? Remember, we are discussing just grams of fuel here. What is the likelihood of the seal failing versus the likelihood of a plug blowout or a weak spot in the cardboard tube holding a solid fuel motor?

They are hobbiest-supported organization for solid-fuel rockets. I expect if anyone built these engines we'd need a new organization to handle them properly. They would have new capabilities and limits. And, initially at least, they'd have no governing authority outside of the FAA.