Ramjets before WWII--early cruise missiles?

The first attempt to weaponize a ramjet came in 1915, when the Hungarian inventor Albert Fono proposed to build an artillery shell with a built-in ramjet that would activate after the shell was fired from a gun, substantially boosting range and payload for a given cannon size. The proposal was IOTL rejected.

What if it were not, and supersonic ramjets were a fairly mature propulsion technology by 1918 and during the interwar? What impact would a functional supersonic engine (even one that could only be used after you first got up to Mach 1) have on the development of aviation technology and air strategy between the wars?
 
You won't get cruise missiles, not as we think of them now. The control and guidance systems didn't exist back then to provide anything like the sort of accuracy that we expect today. You might get some sort of long-range artillery, an earlier V1 equivalent with only the most rudimentary guidance, but I doubt propulsion systems were what stood in the way of this. It was possible to build unmanned aircraft long before jet engines arrived after all, and a V1 is essentially an unmanned aircraft. So from that point of view we're talking about bombardment weapons, which would be launched on a bearing and dive at a pre-set point, hopefully delivering their payload. They might or might not hit the city they were aimed at and would have no target-seeking qualities whatsoever.

Now, in terms of manned aircraft, things are less obvious. Again, control systems are going to be a big issue - early supersonic aircraft were notoriously difficult to handle, and if the propulsion system won't work below Mach 1 that raises a whole set of other issues. Also think about the design process and materials available: it might be possible to build an aircraft in 1915 that could survive supersonic speeds, but it would be an expensive one-off that would probably kill a lot of test pilots before succeeding. Finally, there's the facilities required. Again, if a powered landing requires touching down at supersonic speeds, that is going to have huge implications for where and how many airfields can be built.
 
Problem is, only way in WWI to get to the speeds where ramjets work, is to fire them by a cannon.
Vacuum tubes won't be up to that for some time.
 
Structures in WWI won't stand up to the stresses, metals/skin for airframes won't take the heat, you'll need hydraulic or electrically boosted control surfaces, and much more. The technology for the whole package just is not there.
 
Problem is, only way in WWI to get to the speeds where ramjets work, is to fire them by a cannon.
Vacuum tubes won't be up to that for some time.

I don't see why we need vacuum tubes, because we're not talking about a sophisticated missiles here. If we think in terms of a crude autopilot that might be achieved with simple electrical and mechanical linkages. Really all it has to do is stay on course and dive after a given period of time, I'm sure that can be achieved. When did gyroscopes become part of autopilots?

Structures in WWI won't stand up to the stresses, metals/skin for airframes won't take the heat, you'll need hydraulic or electrically boosted control surfaces, and much more. The technology for the whole package just is not there.

I agree, pretty much. Like I said, someone willing to push the bleeding edge of technology might be able to build an aircraft that could manage it, but it would not be remotely practical for mass production.
 
When did gyroscopes become part of autopilots?

Since Lawrence Sperry and Carl Norden made early flying bombs in 1918. Altitude can use a simple barometric system, but direction far more difficult.
After the War, Sperry concentrated on autopilot systems, and Norden on bombsights

In 1920, the World airspeed record was 194mph
 
Last edited:
I suspect an ejector ramjet system might be workable in the 1930s. I'd look into hydrogen peroxide oxidant burning with kerosene or other hydrocarbon fuel. This rocket can be used to rapidly (say 3-6 Gs) accelerate a winged jet-type aircraft to low, subsonic ramjet speeds; then we'd throttle back the oxidant flow and use the reduced rocket with high fuel flow to inject fuel into a ramjet-compressed air chamber. Not only do we get additional power for the net jet from burning fuel in the air inducted, also the total heat released by both the rocket and the supplemental air-burned fuel drives a considerably greater mass of nitrogen from the air, thus considerably greater thrust than the rocket alone would produce in a vacuum can be provided.

I am not going to try to do the math tonight but I was thinking about this some months ago--at that time it seemed realistic to me that thrust might be sustained with realistic conditions for 15 minutes or so. That's not useful for bombing missions (thought it might for short-range tactical attack missions) but it could be good for a rapid-climbing point defense interceptor.

Or a stand-off cruise missile, launched from an airplane or airship--that would cut down on the requirement to carry lots of oxidant just to get up to ramming speeds first, by diving for speed instead. With the modest acceleration far less than being shot from a gun, it would be possible to have some kind of simple control mechanisms or even electronics aboard. I've often wondered how hard it would be to protect a radio-guided missile from jamming simply by shaping its antenna so it only "listens" to signals coming from behind it, not to the side or ahead. If that can work a very simple radio control system, cheap to make and expendable, could serve to guide the bomb to target.

It would work best if the designers can master basics of supersonic flight control of course, so the earlier development starts the better, as the only practical way to do that would be to test evolving aerodynamic theory with trial-and-error designed drones. Knowing what we know today I'd make delta wing shaped things with area rule and concentrate on getting well past Mach 1, to 1.5 or so. They won't know any of that before the fact unfortunately.
 

Cook

Banned
What if it were not, and supersonic ramjets were a fairly mature propulsion technology by 1918...

Supersonic ramjets were a technology in its infancy in the 1960s, and that is even after the truly extraordinary advances in aerodynamics and metallurgy that had been achieved in 45 years, so frankly I don't think you could achieve the same in a matter of years.

...have on the development of aviation technology and air strategy between the wars?

Even if they were in use as boosters for artillery rockets, that wouldn't translate into their use in aircraft; ramjets can't be throttled, and produce enormous amounts of vibration.
 
At work.

Please look into the works of Professor Alexander Lippisch.

His ideas/design for an all wood, ram-jet powered aircraft would seem to match the OP's thoughts/request.

Also the pre-WW 2 development work or Frenchman Roland Payen into delta wing designs.

Much cheers to all.
 
The first major ramjet missile- the US RIM-8 Talos- had to undergo nearly 13 years of intensive development (throughout which the program was a top priority for the Navy) before the ramjet (along with the guidance, rocket booster, guidance, and aerodynamics) was considered capable of the performance expected of it. In fact, the first few years were focused just on figuring out how to make the ramjet produce more thrust than drag.

A detailed history of the problems specific to producing a functioning ramjet for the Talos missile is here. Note that this does not cover the problems related to the rocket booster needed to get it up to speed, the guidance system, the supersonic aerodynamics, and the warhead. Those are covered here, here, here, and here, respectively.
 
The first major ramjet missile- the US RIM-8 Talos- had to undergo nearly 13 years of intensive development (throughout which the program was a top priority for the Navy) before the ramjet (along with the guidance, rocket booster, guidance, and aerodynamics) was considered capable of the performance expected of it. In fact, the first few years were focused just on figuring out how to make the ramjet produce more thrust than drag.

https://en.wikipedia.org/wiki/Leduc_0.10 COUld have flown in 40-41 if not for the war
 
Top