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I've been reading about the early rocket work during WW2. They tried all sorts of fuels, hydrogen peroxide, hydrazine, red fuming nitric acid...

Just in the scope of JATO/RATO, has there ever been one working just with kerosene? The airplane would accelerate normally to sufficient airspeed such that enough oxygen was flowing, then the JATO would ignite. This would then boost the aircraft very rapidly up to a high altitude.

I think this could be called an afterburner all by itself (without the turbojet lol), or maybe even a ramjet all by itself. Whatever you call it, it has no moving parts other than a fuel pump. So I am wondering if this concept was ever tried during WW2 or shortly thereafter.

(P.S., surprised there is not JATO tag, nor RATO tag. I will create it but also use "takeoff" for visibility purposes.)

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    $\begingroup$ For a rather complete overview of early rocket fuel work, see Ignition! by John Clark. $\endgroup$
    – Peter Kämpf
    Mar 5 '18 at 17:32
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    $\begingroup$ C-130's were all built equipped for JATO, but during the time I flew them (1990's) only the Antarctic birds on skis and the Blue Angels airshow bird actually used them. Part of the reason that nobody else did was that carrying around the solid rockets -- Class B explosives -- would be a pain in the neck for little benefit (if you can get in to the field, you can probably get back out again unaided just fine). Kerosene is abundant on the Herk (fuel tanks), but LOX being piped back to mix with it, on command, would be a MAJOR undertaking, with catastrophic results if things go wrong! $\endgroup$
    – Ralph J
    Mar 5 '18 at 23:21
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    $\begingroup$ Hm -- speaking of Antarctic C-130s...why are JATO bottles so common on them? $\endgroup$
    – Marius
    Mar 6 '18 at 2:32
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    $\begingroup$ @marius, much of antarctica is at an altitude of ~2000 to 3000 meters and so to furnish adequate takeoff performance, the rocket boost is frequently needed. $\endgroup$
    – niels nielsen
    Mar 6 '18 at 4:07
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A RATO unit's purpose is to give a high impulse very quickly, it does this by combining a fuel with an oxidizer causing rapid combustion in a chamber, and forward thrust from the equal and opposite reaction. Kerosene is a fuel, but without an oxidizer you don't have a rocket, you have some lamp oil burning. If you wait until the airplane is moving then it's lamp oil burning in a wind, giving you no benefit.

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    $\begingroup$ -1, "lamp oil burning in wind" is a poor description of an afterburner or ramjet. Those too use kerosene "without an oxidizer", yet provide enormous thrust. Indeed, the ramjet can be started at takeoff speeds, and the ram effect will tend to increase both speed and thrust even beyond Mach 1. Also note that afterburners are effectively used like JATO/RATO, just not discardable. They turn on afterburner at launch on a carrier. So "lamp oil burning in a wind, giving you no benefit", is clearly false. $\endgroup$
    – DrZ214
    Mar 6 '18 at 4:34
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    $\begingroup$ @DrZ214 An afterburner relies on hot, high-pressure oxygen compressed by the jet engine. It does not have "no moving parts", but rather relies on the largest and most complex moving part on the whole aircraft. It would not work if the engine was shut down, when that happens we call it a tailpipe fire. $\endgroup$
    – user71659
    Mar 6 '18 at 5:02
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    $\begingroup$ @user71659 Okay fair enough. I still maintain that a properly designed ramjet can be ignited at takeoff speeds and provide more and more thrust even beyond Mach 1. $\endgroup$
    – DrZ214
    Mar 6 '18 at 5:19
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    $\begingroup$ @DrZ214, ramjets compress air using forward motion, you need considerable speed to start one. Are you thinking a pulse jet maybe? Those work without forward motion but have low impulse, you don't get much that much thrust. $\endgroup$
    – GdD
    Mar 6 '18 at 10:05

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