Re: model ramjets

Those were low power reloadable gas generators: a rocket, but less power than the Estes blackpowder engines, with a longer burn time. A good choice for light balsa freeflight planes.

He might have been looking for the actual model pulsejets of the '60s, like the Dynajet or TigerJet. Used white gas or glofuel, a spark plug for starting along with pressurized air.

Loudest things I ever heard, and yes, sometimes Cops would get called when you fired them up. Worse than 'real' fullsized turbines spooling up.

For Control Line speed events, or R/C, for the crazy.

A few seconds of operating, and the tube glowed red hot

The Jetex engines were rocket engines, but with small nozzle and low thrust so they could be used on lightweight freeflight models.

The Dynajets were pulse jets.

There was a third type, from a company called MEW. These were weird things, of which there were no full-size aircraft equivalent. They were basically a pressurized gas rocket, like the old CO2 cartridges, but with two extra little improvements. They were heated by bleeding off a little bit of the propane fuel to heat the container, adding a little bit of total impulse, plus they had a thrust augmenter. This drew in ambient air and accelerated it, reducing a high velocity low thrust flow to a medium velocity, higher thrust. These were never popular, however.

Now, of course, there are REAL turbojets and turboprops for model airplanes, IF you have the money.

I remember seeing advertisements for one to be strapped to a bicycle and about 36" to 42" long. It was to be made by the average machinist and the advertisements appeared often in old Popular Mechaniics magazines. I have a copy of the ad and if I can dig it out, I'll post it on the binaries group.

check here

the bike is near the bottom if you go to DIY Galleries section

you can also check

for pulse jet plans, kits and assembled engines...there are still a couple of mfg around

Thanks Mike! I remember now, the Dynajet was the American one, which sold in England too. The British one was the Juggernaut, very similar to the Dynajet, and one of which I owned in my youth. As Stephen pointed out, they were of course pulse jets, not ramjets. Many control-line modellers used them, notably at Fairlop airfield (long since gone now) and the noise was unbelievable. Prince Bira used to test his Formuila 1 cars there and his engines made far less noise ! I seem to remember model pulse jets were eventually banned from model aircraft meets after some fatal accidents with them.

Jim Hawkins

Jim Hawkins

Yep. Though a different company, and a larger version, that is the same prinicple the old MEW engines used. I never bought one- don't know if it would power a model or not.