Why Riedel Starter ?

[yidal8]

I was wondering about how the Riedel starter engine came to be used in the turbojets. The English used electric stater motor in their early turbojets. Why did the germans go with a complex (and heavy) statrter system like the Riedel?
Was the Riedel available from previous program for amother application, or specially for the jet engine?

 

[Milosh]

I would say because it was a self contained starter unit. An electric starter needs a cart full of batteries or external generator and a long cable.

 

[Snautzer01]

see here for comprehensive data on the starter

Riedel Anlasser

 

[robwkamm]

there was one on ebay a few weeks ago. check past sales youll see it. it was missing the vital fuel injection unit or i would have snapped itup.went through with nosale.

 

[Gixxerman]

Does anyone know what sort of revs thoseRiedel units got up to?

It's interesting because a clean running (fuel injected) 2 stroke was long an interest to the automotive world (2 strokes are much simpler engines with fewer moving parts and so much cheaper to manufacture).
Although interest has since cooled as the investment in cleaner running 4 stroke engines is now immense not likely to be succeeded by anything other than an entirely different type of engine altogether (the fuel cell?).

In recent times (say, after the 1980's) fuel injection was always considered difficult because of the high engine speeds (revs) and their frequency of the injection (a fuelling action every 'stroke' rather than every other stroke on a 4 stroke motor).
Some have since managed it (Ford had the Orbital 2 stroke engine amongst several designs) but cars seem unlikely to ever go there.
Motorcycles, boats snowmobiles may still be a different matter.

 

[razor1uk]

Sorry for the extremely late reply, as far as i can tell from 262 videos, and data, the Riedel could spin upto 10,000 rpm, maybe much higher upto around 15,000 rpm - they were reduction geared down to the starter dog gear, before the even more reduced gearing on to the engines starter drive ring - Reidel was ready to be switched off on the 262 Jumo's when the engine was able to run itself was at over 800 turbine rpms once the engine was igniting its fuel, and I believe once 900 (turbine)rpms was reached the Reidel was shutdown.
Reidel's didnt use fancy porting or Kaaden/expansion pipes, nor are details to their cc found often - I think 350 to 450cc might be in the ballpark.

 

[camman]

Well, by scouring the internet, I've gathered that they are 270cc engines (70mm bore, 35mm stroke) that make 10 hp at 10,000 rpm with a centrifugal clutch that engages at 4000 rpm. They then have a 4.8:1 gear reduction between them and the jet engine.

 

[razor1uk]

270cc, mmm, a possibly extravagant go-cart motor size compactness then, just would need a gearbox or moped style centrafugel belt and pulley system... sorry thinking of cart usuages...