Possible Alternate Jet engine pre-WWII

OK, this is a little out there, and likely has already been thought of before, but I was considering rocket and jet development during and after WWII and wondered what could have been done that was 'simpler' than a traditional jet engine. Of course the obvious thing is a ramjet (for varying degrees of 'simpler'), using a rocket to push it up to speed before starting the ramjet. It was already known of in principal at the time and could have been done, but getting a craft close to or beyond the speed of sound in the 30s or early 40s is a not really likely.

Then I had a thought.

What if the rocket was inside the ramjet? ie, the cone on the intake had, at it's rear, a small rocket creating a supersonic flow inside the engine, and at the same time sucking air from the front via Bernoulli flow, then adding more fuel and igniting like a traditional ramjet. No turbines, no moving parts other than the rocket engine itself and the ramjet fuel injectors. Wouldn't be as efficient as a jet engine as the rocket would need oxidizer, even if most of the ramjet dominated the thrust, though once you pushed it close to the speed of sound you could shut off the rocket.

I know, Ramjets were always hard to do in of themselves so it may be more complicated than a turbojet engine anyway, but I just wondered if a) that was at all possible, and b) if it was possible earlier than turbojets, and c) if someone has had the idea before anyway. I'm assuming so as there has been an awful lot of work on ramjets done over the decades, a ton in the 50s and 60s alone.
 
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1946 test of the Marquardt XRJ-30-MA Ramjets
Not so good when only one side lights.

Very inefficient way of burning fuel to go a little faster
 
Did they have to do a power dive to get fast enough for the ramjet to work? I thought you had to be close to the speed of sound to function? In fact the airflow in the engine to be supersonic, but you could use the intake to boost internal speed a little to work just below. Though I admit I haven't looked in depth at ramjets.
 
Pre-war have Helicopter tip jets (as used on Faireys Rotadyne) become a design feature for torqueless roter drive for Helicopters. Development through the war years should see a mature technology by the late forties!
 
I thought the tip jets weren't ramjets in principal? Or were they and the sheer rotational speed got them fast enough to be functional? Some of those coptors did use tip rockets I think, feeding both fuel and oxidizer. I do know the ramjet principal was known early in the century, and models were made, though due to limitations were never actually flown I thought. *shrugs* I really need to go into the history of this a little more.

I was more wondering if there was a way to force the supersonic flow inside a ramjet (in this case with an internal rocket) and if this had been studied in the past. Plus if it was something that a 30s or 40s era tech base could produce. Admittedly a rocket (if liquid fueled. A solid one inside?.. ouch. No way to shut it off!) would itself be a challenge to manufacture and be reliable. Those done during the war years (and yes, before) were temperamental to say the least and were costly even when refined to a more stable state. Starting early probably could get something with a simpler base, say a peroxide/kerosene rocket which seems easier to get with lower technology/metallurgy involved and also doesn't need any work on cryogenics.
 
I'm aware of buzzbomb engines :) , and I've had ideas on that before, I'm really asking is this rocket/ramjet hybrid possible or has it been thought of and disproved before? As I understand it all the ramjet needs is supersonic flow inside the engine, during constriction and ignition. Thus finding a low tech method of forcing such a flow would allow a jet without complex turbine blades to be made earlier.
 
For a pre-WW2 ramjet then your probably want to look at Leduc - Wiki Link. If one believes the French wiki on him he started work 1934 and got round the 'starting' problem by carrying it up on a mother aircraft then dropping it.

A quick search reveals the rocket/ram jet combo first being patented in the 50s, (Here) but nothing much being done with it. I suspect the problem may be the limited appliation of ramjets (mostly missiles and similar) and the deadweight of the rocket once you've got up to speed.
 
That looks very close, but not quite what I was meaning. Though it's possible what I was thinking was just plain impossible. The one you linked El Pip seemed to be able to switch between being a ramjet engine to being a rocket. What I was meaning was using an internal rocket to make a ramjet work at lower airspeeds.

I'm wondering if I'm just explaining this wrong. If I get the time I'll make a sketch of what I was meaning.
 
I'm aware of buzzbomb engines :) , and I've had ideas on that before, I'm really asking is this rocket/ramjet hybrid possible or has it been thought of and disproved before?
What you're describing is basically an air-augmented rocket. They've been perennially studied to produce high-performance high-altitude vehicles, but they have a relatively high degree of complexity and a relatively low degree of efficiency (they do get a big boost compared to regular rockets, but this still leaves them far behind a conventional jet). The Meteor missile uses an air-augmented design, and the (canceled) Gnom ICBM from the 1960s would have done so to enable an ICBM that was comparatively lightweight and small. So probably the most reasonable use of this design in a WWII context would have been to augment a rocket-powered aircraft so that it would have a bit more performance, or as an effort to make missiles more efficient and longer-ranged.
 
Whittle gets the support (and the financial reward and recognition) he deserved in the 30s (the government backs his design and perhaps have Griffith - a pioneer of metallurgy and later Jet engine collaborator - collaborate more closely with Whittle in the 30s rather than be critical of his designs) and as a result Frank does not work himself into multiple nervous breakdowns trying to build his Jets on a shoestring with little or no official support.

Such was the pressure he was under to deliver a working and practical Jet engine in 1940 he was working 16 hour days, his weight had dropped to 9 stone / 57 KGs and he was addicted to benzedrine.

It amazes me that the 2 most import British Aircraft engines of WW2 the Merlin and the W2/500 Jet engine were the result of 'private venture' despite indifferent support from the government that I think was massively negligent.
 
Whittle gets the support (and the financial reward and recognition) he deserved in the 30s (the government backs his design and perhaps have Griffith - a pioneer of metallurgy and later Jet engine collaborator - collaborate more closely with Whittle in the 30s rather than be critical of his designs) and as a result Frank does not work himself into multiple nervous breakdowns trying to build his Jets on a shoestring with little or no official support.

Such was the pressure he was under to deliver a working and practical Jet engine in 1940 he was working 16 hour days, his weight had dropped to 9 stone / 57 KGs and he was addicted to benzedrine.

It amazes me that the 2 most import British Aircraft engines of WW2 the Merlin and the W2/500 Jet engine were the result of 'private venture' despite indifferent support from the government that I think was massively negligent.
Whittle could be his own worst enemy. He had a severe case of paranoia when it came to his technology. It could slow things down even when he was getting support. The much maligned relationship with Rover failed as much because Whittle wanted full control over his engine and was furious when Rover straightened it out to improve manufacturing while improving airflow. He did trust Rolls-Royce, and didn't have any problem when they used this particular part of Rover's work as well as improvements from the W2B/500 to create the Derwent.

The Merlin was developed as a Private Venture, sure, but that was not uncommon for Aircraft Engines of the interwar period. It first ran in 1933 and by 1934 was mentioned as a preferred engine in an Air Ministry Spec in 1934. So not without any government support. Likewise, though Whittle certainly could have used government funds in the 1930's when working on what became the WU, by the time the W2/500 came around he had a considerable amount of government support.
 
What you're describing is basically an air-augmented rocket. They've been perennially studied to produce high-performance high-altitude vehicles, but they have a relatively high degree of complexity and a relatively low degree of efficiency (they do get a big boost compared to regular rockets, but this still leaves them far behind a conventional jet). The Meteor missile uses an air-augmented design, and the (canceled) Gnom ICBM from the 1960s would have done so to enable an ICBM that was comparatively lightweight and small. So probably the most reasonable use of this design in a WWII context would have been to augment a rocket-powered aircraft so that it would have a bit more performance, or as an effort to make missiles more efficient and longer-ranged.
I think I've heard the term before, but didn't equate it to what I was thinking of. Makes sense, and a shame. Thought it would be simpler but less efficient... in the same way that ramjets are 'simple' :)

Knew someone must have thought it up before. Ah well.
 
Whittle could be his own worst enemy. He had a severe case of paranoia when it came to his technology. It could slow things down even when he was getting support. The much maligned relationship with Rover failed as much because Whittle wanted full control over his engine and was furious when Rover straightened it out to improve manufacturing while improving airflow. He did trust Rolls-Royce, and didn't have any problem when they used this particular part of Rover's work as well as improvements from the W2B/500 to create the Derwent.

The Merlin was developed as a Private Venture, sure, but that was not uncommon for Aircraft Engines of the interwar period. It first ran in 1933 and by 1934 was mentioned as a preferred engine in an Air Ministry Spec in 1934. So not without any government support. Likewise, though Whittle certainly could have used government funds in the 1930's when working on what became the WU, by the time the W2/500 came around he had a considerable amount of government support.
Oh certainly by the time they were flying the Gloster test aircraft the AM had sat up and finally taken interest in his work

What I am talking about is the earlier period when by contrast his work was not supported and in fact officially criticised resulting in the private backers not backing him as much as they had originally said

I am not suggesting Jet powered Spitfires in 1940..................god dammit who am I trying to kid here....yes.......I am suggesting Jet Powered Spitfires in 1940

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Oh certainly by the time they were flying the Gloster test aircraft the AM had sat up and finally taken interest in his work

What I am talking about is the earlier period when by contrast his work was not supported and in fact officially criticised resulting in the private backers not backing him as much as they had originally said

I am not suggesting Jet powered Spitfires in 1940..................god dammit who am I trying to kid here....yes.......I am suggesting Jet Powered Spitfires in 1940

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;) that is the dream. I think it is more complicated than just throwing money at Whittle in 1930 though. I could maybe see something like the Derwent V/Nene flying in 1942 and fielded in 1943 though.
 
;) that is the dream. I think it is more complicated than just throwing money at Whittle in 1930 though. I could maybe see something like the Derwent V/Nene flying in 1942 and fielded in 1943 though.
Oh totally - Meteors and Vampires in mass squadron service for D-Day would do nicely

It is more complicated - a lot of metallurgy and other big words needed to be sorted - but throw enough money and smarts at it earlier....!
 
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