rocket up your ass...

[cosmicbike]

I have a classic Dynajet 'Red Head' pulse jet. It has everything that a pyromaniac dreams about: inflammable liquids, huge flames, glowing metal and noise, lots of noise..

The ignition system is a 'trembler' circuit which generates a HT spark in the combustion chamber. Energetic pumping of a track pump forces air over a venturi, drags petrol vapour into the combustion chamber where after a few pops and bangs the pulse jet howl, if you're lucky, starts up. Awesome

The neighbours tend to disagree with my definition of fun but by the time they're mobilised the garage door has been pulled down, engine silenced and there's no sign of the unsilenced large block V8 that they imagine to be the source of the noise....

The engines are still used in model aircraft in the UK in the control line speed discipline. They hit speeds of around 200 mph with a 'pilot' hanging onto handle at the other end of the wires spinning around trying to keep up with the rotations. It's an awesome sight.

Here's a video of a pulse jet engine strapped to a control line speed plane. The engine is more or less identical to the one that I have but is quieter because it is operating in open air and not using a garage as a resonator box.

Lucky bugger
Knew they were banned on RC, nice to see the CL speed freaks still use them. Watched the CL speed and team racing at the Nats a few years back from the comfort of my tent pitched opposite the CL circles. Quite how the chaps managed not to fall over each other is beyond me, but the single wing speed stuff was a bit special to see..

 

[vernon]

Lucky bugger
Knew they were banned on RC, nice to see the CL speed freaks still use them. Watched the CL speed and team racing at the Nats a few years back from the comfort of my tent pitched opposite the CL circles. Quite how the chaps managed not to fall over each other is beyond me, but the single wing speed stuff was a bit special to see..

They are not banned on RC. Most RC clubs ban them because they have to operate within strict noise limits else they lose their flying sites if too many noise complaints are received. A couple of pulse jet runs will jeopardise most flying sites.

Here's the guidance from BMFA

(2) Radio Control
Radio control pulse jets may be flown under the
following conditions:

• (a) That the express written permission of the owner/controller of the site is obtained in advance with due regard for noise considerations.
• (b) That the express written permission of any model flying club using the site is obtained in advance.
• (c) That monitoring of the area surrounding the site for noise complaints is carried out on an on-going annual basis.
• (d) That all operators of such models on the site shall hold a Power Achievement Scheme Fixed Wing 'B'
• (e) That CAA exemption certificates as required are obtained and the conditions on them are followed.

Any regulation specifically concerning reaction motors does not apply to small solid-fuel units of the Jetex type, nor to solid fuel rocket motors of the Rapier type or to recognised pace Model power units used in accordance with the appropriate BMFA approved codes of practice.

 

[vernon]

You focus on the plane rather than the background to reduce any dizziness,I used to fly
Team race back in the 80's.
The planes aren't as fast as the pulse jet,still around 100mph though and there's three of you
in the centre

Team race is civilised compared to C/L combat

 

[vernon]

He's not wearing a helmet.......

I'm not convinced that a slow speed topple is the greatest risk on offer there.

I wasn't wearing my serious head when I typed that message....

 

[vernon]

lol does the man in the middle get dizzy? We used to do that with a broomstick and see how long we could stand up for

For that particular discipline there is a sturdy pole mounted in the centre of the circle with a special mount. There is a special handle design which has to be mated with the mount before the speed attempt can be timed. Hanging onto the pole offers a degree of vertical stability but, as posted elsewhere focussing on the plane helps as does practice. I fell over the first few times when doing circular flying (control line) but you do get used to the spinning until you take on a bigger engines plane and a faster rotation rate then new acclimatisation takes place.

 

[vernon]

You have such a thing?

Somewhere. I think my wife has tidied it away.

 

[Pennine-Paul]

Team race is civilised compared to C/L combat

Used to fly diesel combat too,got as far as the semi finals in one round of the british champs many moons ago,then i moved to the western slopes of the pennines
and flew slope soarers and a bit of f3b in the british national league

 

[Smurfy]

There's almost as much engine as there is plane!

 

[Easytigers]

How does he stop the bike? Surely the brakes are going to do diddly squat!

 

[vernon]

There's almost as much engine as there is plane!

Yep. Too much plane increases drag and lowers the speed.

Any fule kno that.