Ken, It's a small world out there.
Mitch Started a rocket company with a partner, that didn't work out.
The partner started a similarly named company, who hired an intern.
They (we) tried the N2O/C2H5OH mixed monoprop under a phase I SBIR.
(some very limited success*). The intern left and started Firestar.
The crazy part was the intern was significantly more safety concerned
than the leadership of the company he left. I think the term
"There are no safety concerns" comes from the people writing the
checks, not the people told to stand close to the test stand.
* Successes were singular occurrences. One due to insufficient mixing,
once with a "Powdered Injector". The powder based injector geometry was
the last test in the series, and supposedly worked. (interns idea).
Rumor has it that the Intern jumped to NASA about the time FireStar
moved out of Colorado. Did Firestar ever pick up those tests ???
-gar.
From: Ken Doyle <rocketken@xxxxxxxxx>
Date: Sun, 22 Apr 2018 11:06:47 -0700
Subject: [AR] Re: arocket Digest V6 #100
(It's been some time since I've responded to an arocket post, so please
excuse me if I have the reply addressing wrong.)
I also have some experience with Nitrous/Acetylene as a monoprop, from
time
with Firestar in Mojave, prior to the ALASA effort.
John Schilling is quite right in his cautions against pursing the
technology/(deadly-foolishness) without a significant budget. John
mentioned an eight-figure budget, although I would see that as a great way
to "make a small fortune from a large fortune" effort
I was doing significant work on the stuff with a "use prior programs scrap
plumbing" budget, and I'm lucky to have survived. For instance, I had no
money for propellant bottle burst discs, or generator fuel at times. I
blew up large quantities of salvaged tubing and Swagelok fittings from my
work on prior programs on the former Rotary Rocket, RASCAL, RPE, and
Protoflight/QuickReach/FALCON sites we were using.
I did work on several mixtures of Nitrous/Fuel blends at Firestar. The
Nitrous/Acetylene blends were the worst; and mixtures with other fuels
were
"relatively" less deadly. My conclusion is that none of the blends will
ever be made relatively "safe", with the hardware flight-weight. Although
the potential for system simplicity is appealing in monopropellants, I saw
no path to acceptable user or vehicle safety levels with the technology.
Some success was achieved with gas-phase rocket motors and Flashback
Arrestors. By the time I left for less dangerous work, no success in
liquid-phase rocket motors had been achieved. Liquid-phase "Flashback
arrestors" which were effective and not massive were not achieved. The
Nitrous/Acetylene blends which I made and tested were quite shock
sensitive, and prone to going kerblewy with any motion at temps as low as
50C/130F.
(Meanwhile, I was chastised by the ignoble leadership for acting afraid of
the stuff; as not showing casual handling was not in line with the
mantra/lie that we had a safe product.)
I recall writing to Mitch Clapp with my concerns about using a manned
aircraft with the ALASA program. He replied, expressing knowledge of the
challenges. I was relieved to see the project cancelled.
I am now a firm believer that Oxidizers and Fuels should be kept apart
until they meet in a rocket chamber.
The Wiki article on NOFB is an absolute lie on the safe handling aspects,
and could lead others to attempt to continue with the technology. I
should
take the time to go put my edits into the piece.
Now happily working with far more conventional propellants, somewhere in
WA,
Ken Doyle