Do they really make Jetex fuel from bat guano?
No, Jetex fuel isn't made from guano of any flavor. Actually the original Jetex propellant was formulated of an exotic blend of guanidine nitrate, 2,4-dinitroresorcinol, and some other hard-to-find chemicals.
(There is a long and very circuitous link between the word "guano" and "guanidine," but suffice to say they're not really related as far as rocket science is concerned.)
Note that guanidine nitrate is NOT the same as nitroguanidine! These are two distinctly different compounds.
The original Jetex propellant pellets were a slow-burning, low-temperature composition that required a complex catalytic combustion process. They're not like other rocket propellants, and stand in a class of their own.
All Jetex motors require an alloy metal screen fitted between the propellant pellets and the exhaust nozzle. As the pellets burn and decompose, the byproducts pass through this "catalytic converter" screen -- a necessary step in their combustion process. The wire screen isn't simply to protect the nozzle from clogging.
The original Jetex propellants were mixed in the laboratories at Imperial Chemical Industries (ICI), in Scotland. They were an adaptation of several unusual British solid propellants developed to power anti-aircraft target drones during World War II. After the war, Charles Wilmot and Joseph Mansour (both keen model airplane enthusiasts) designed a series of small, reloadable rocket engines to power model airplanes, racing cars, and boats. They called their novel motors "Jetex," and introduced them in 1949. By the 1950s, thousands of enthusiasts were flying Jetex-propelled models in America and across Europe.
Jetex "50" Motor
Jetex "Scorpion" Motor
Jetex "Spacemaster 600" Motor (the largest)
Eventually ICI decided that their small production of Jetex propellant wasn't worth the time, trouble, and risks, and stopped making it. Though the formulation is well-known, since then no other suitable replacement has appeared.
As Wilmot and Mansour tweaked their Jetex propellant compositions and came out with several larger rocket motors, their pellets were sold under a variety of names and brands. "Red Spot" was one particularly favored formulation of the 1960s. Sometimes importers repackaged the Jetex pellets, and sold them under their own brand names (American Telasco, among others).
"The Good Stuff"
When the supplies of original Jetex propellants dried up, other formulations were tried. Some were sold as "Jet-X" propellant (usually in the form of rough, dark grey pellets). None of these later compositions work very well, unfortunately, for a variety of reasons.
Post-Jetex era, non-original pellets (they don't work for us ... )
So if you want to buy some "real Jetex" propellant, you'll have to search the eBay listings and compete with collectors (who have no intention of burning their hard-to-find winnings!). Look for those with the characteristic red-and-yellow Jetex packaging, and showing their origin as the Jetex works, in Totten (near Southamption), UK.
For complete formulation details (and much, much more about Jetex-type propellants), be sure to get a copy of "Advanced Nitrate-Type Solid Propellants," or "Unusual British Solid Propellants," both listed in our eBay Store.