Only just started but already some gems on fuel situations that went boom
Also, learned about "mach diamonds" or "shock diamond": Shock diamonds (also known as Mach diamonds or thrust diamonds) are a formation of standing wave patterns that appear in the supersonic exhaust plume of an aerospace propulsion system, such as a supersonic jet engine, rocket, ramjet, or scramjet, when it is operated in an atmosphere. The "diamonds" are actually a complex flow field made visible by abrupt changes in local density and pressure as the exhaust passes through a series of standing shock waves and expansion fans. Mach diamonds are named after Ernst Mach, the physicist who first described them.
Esnault-Pelterie use of benzene (as Glushko's of toluene) as a fuel is rather odd. Neither of them is any improvement on gasoline as far as performance goes, and they are both much more expensive. And then Esnault-Pelterie tried to use tetranitromethane, C(NO2), for his oxidizer, and promptly blew off four fingers. (This event was to prove typical of TNM work.)
Unfortunately, in his calculations Dr Eugen Sänger naively assumed 100 percent thermal efficiency, which would involve either (a) an infinite chamber pressure, or (b) a zero exhaust pressure firing into a perfect vacuum, and in either case would require an infinitely long nozzle, which might involve some difficulties in fabrication.
Boranes are unpleasant beasts. Diborane and pentaborane ignite spontaneously in the atmosphere, and the fires are remarkably difficult to extinguish. They react with water to form, eventually, hydrogen and borec acid, and the reaction is sometimes violent. Also, they not only are possessed of a peculiarly repulsive odor; they are extremely poisonous by about any route. This collection of properties does not simplify the problem of handling them. They are also very expensive since their synthesis is neither easy nor simple.
[...]
And then the whole program [chemistry of borohydrides] was brought to a screeching halt. There were two reasons for this, one strategic, one technical. The first was the arrival of the ICBM on the scene, and the declining role of the long-range bomber. The second lay in the fact that the combustion product of boron is boron trioxide (B2O3, and that below about 1800 degrees this is either a solid of a glassy, very viscous liquid. And when you have a turbine spinning at some 4000 rpm, and the clearance between the blades is a few thousandths of an inch, and this sticky, viscous liquid deposits on the blades, the engine is likely to undergo what the British, with precision, call "catastrophic self-disassembly"
