What's up with this Eindecker's Engine?

[Bluesman]

I was gathering reference pictures for my next build, a Fokker Eindecker EIII when I came across a picture of a repro in Seattle, I think in On display in the Personal Courage WIng of the Museum of Flight. If you look at the engine, it appears to have copper exhaust pipes?? Original pics and a picture of the engine of an original Eindecker in the London Museum of Science don't show them. Were there multiple engines in use for the bird, or is this just a builders mistake? I couldn't get my pic of the Museum of Science Eindecker to upload, but it looks like the black and white photo.

[ondra]

The engine on the Eindecker in Seattle looks pretty much like a Le Rhóne 9C, used e. g. on Nieuports. I have not heard of any cases of these engines being actually used during WWI on Eindeckers, so this rather looks like a builder's mistake - they simply took a rotary engine from WWI. Also notice that the propeller is pretty far from what you can see on the second photo (Garuda propeller).

Eindeckers were equipped either with Oberursel U.0 (7 cylinders, E.I) or with Oberursel U.I (9 cylinders, E.II - E.III).

[RLWP]

The copper pipes carry the air/fuel mixture from the crankcase to the combustion chamber. Rotary engines don't usually have an exhaust, the valve just opens to atmosphere

In this picture:



the pushrod opens the exhaust valve in the top of the cylinder. The Oberursel has an automatic inlet valve in the top of the piston to allow the air/fuel mixture into the combustion chamber

Richard

[Bluesman]

The copper pipes carry the air/fuel mixture from the crankcase to the combustion chamber. Rotary engines don't usually have an exhaust, the valve just opens to atmosphere

In this picture:



the pushrod opens the exhaust valve in the top of the cylinder. The Oberursel has an automatic inlet valve in the top of the piston to allow the air/fuel mixture into the combustion chamber

Richard

I did not know that about the rotary engines, thank you for the info. Did the castor oil spray out the same way?

[Des]

The castor oil was mixed with the fuel and once combined with the air it was passed through the copper intake pipes to the cylinders. After combustion the exhaust valve on top of the cylinder was opened and the exhaust gases expelled into the atmosphere. The engine cowl was fitted to prevent the unburnt oil and fuel blowing back onto the pilot, the opening at the bottom of the cowl was to allow the excess fuel/oil to be blown under the aircraft. Not all the unburnt remains went under the aircraft, much of it still managed to cover the bottom of the wings and under the fuselage, the rotary engine was a messy and noisy piece of mechanical engineering.

Des.

[Bluesman]

The castor oil was mixed with the fuel and once combined with the air it was passed through the copper intake pipes to the cylinders. After combustion the exhaust valve on top of the cylinder was opened and the exhaust gases expelled into the atmosphere. The engine cowl was fitted to prevent the unburnt oil and fuel blowing back onto the pilot, the opening at the bottom of the cowl was to allow the excess fuel/oil to be blown under the aircraft. Not all the unburnt remains went under the aircraft, much of it still managed to cover the bottom of the wings and under the fuselage, the rotary engine was a messy and noisy piece of mechanical engineering.

Des.

Were they two stroke engines then?

[IanB]

No, they were four strokes, but used similar means to add the fuel/air mix to the combustion chambers. They also had no carburettors, in the true sense, most had a hollow crankshaft which was used to mix the fuel and air.
 This link may help explain it...

http://www.mekanizmalar.com/rotary_engine.html

Ian

[RLWP]

No, they were four strokes, but used similar means to add the fuel/air mix to the combustion chambers. They also had no carburettors, in the true sense, most had a hollow crankshaft which was used to mix the fuel and air.
 This link may help explain it...

http://www.mekanizmalar.com/rotary_engine.html

Ian

Notice in that video that the exhaust stroke always takes place in the same place - between six and one o'clock. Normally, you would position the engine on the aeroplane so the exhaust happens between say eight and four o'clock - i.e. at the 'bottom' of the engine in the airflow under the fuselage

It's a shame it doesn't show the cams - they get really interesting!

Richard

[RLWP]

I over E.
The single pushrod is a dead giveaway to this type of engine which was prevalent back in those days.
Inlet over Exhaust , the pushrod is for the exhaust , the inlet valve is sucked open by the downward stroke, pulling mixture in , the compression stroke shuts the valve , compression and firing is achieved and the exhaust valve is mechanically opened for gas release.
Pretty sure that's how it works.

That's how it works.

It isn't how I would usually describe I over E though, that's more common on engines with an overhead inlet and side exhaust valve, like this:



https://commons.wikimedia.org/wiki/File:FN_Four_engine_end_section.gif

This one also has an automatic inlet valve. Seeing how critical valve timing is, it's no wonder these old engines produced such low powers for their size

Richard

[ALBATROS1234]

its the wrong engine, thats an 80hp le rhone, the lower pic has a oberursel u. i

[Rob_Owens]

...and the prop appears to be a Levasseur.  If you'd like to turn your WnW Eindeckerer into the museum replica, you'll need this: http://www.ebay.com/itm/292071458043?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[KiwiZac]

Revell's old 1/72 Eindecker has the same engine - maybe they used that replica as a prototype? - so it needs a little work. I saw it on the sprue and immediately thought "Nope!".