50 Horse, 170 Pounds, 7 Cylinder

While its interesting and illustrative and great work, there is actually a serious error visible in that video.
In a rotary engine aircraft, where the ENGINE rotates, the crankshaft is fixed to the aircraft - so the crank is stationary, and the engine rotates around it.
That video doesn't show that, but shows the crank rotating too = WRONG, a bit....

BTW, having half a ton of engine rotating at the front of another less than half a ton of aircraft and pilot means that in some circumstances, the tail wags the dog, so to speak.
If the pilot lets go of the stick, at any point, the plane tended to try to rotate around the engine - which produced a lightning fast flick turn (downwards).
On takeoff this was usually fatal - such planes were said to have killed more pilots in training than in combat.
In combat, this fast flick turn could be relied on to get out of trouble - a non rotary engine plane could not possibly follow this manoeuvre.
Provided it was done high enough to not meet the ground...

Another BTW, these engines had no throttle system in the carburettor - they ran flat out all the time.
Speed was controlled by pressing the magneto kill button - including on the ground, and in a dive, etc.
So in use, were brrrr brrrr brrrr.
If you got brrrrrrrrrrrrrrrrrrr you were out of control, and probably just pulled the wings off.....
 
Rohan said:
While its interesting and illustrative and great work, there is actually a serious error visible in that video.
In a rotary engine aircraft, where the ENGINE rotates, the crankshaft is fixed to the aircraft - so the crank is stationary, and the engine rotates around it.
That video doesn't show that, but shows the crank rotating too = WRONG, a bit....
Click to expand...

Take another look. While its operating as a rotary there isn't really a crank, just a fixed pin, offset from the center of rotation of the engine, on which the master connecting rod spins. When it converts to a radial the fixed pin becomes the crank pin and it travels in a circular path as you'd expect.

I suppose the radial engine is balanced well enough, but in it's rotary form there are no reciprocating parts other then the connecting rods that swing back and forth a bit.
 
Indeed.
But what is not said, or shown, is that rotaries cannot switch to radials, or vice versa, at the flick of a switch
And what is also not clear is that the rotary engine is being filmed from a front view, but the radial is looking at it from the back, effectively.

The reason a radial cannot function as a radial rotary is the carburettor and oil pump setups are TOTALLY different for the 2 engines.
The rotary has the carby feeding fuel/air in through a hollow type crank at the back, in later engines into manifolds to each cylinder - and also the oil feed.
The manifolds have to spin, of course - as also does the (rudimentary) exhaust stacks. As also all the oiling system after the feed.
In the fixed radial, the carby and manifolding can be more conventional, as can the oil pump and feed system.

I suppose the radial engine is balanced well enough, but in it's rotary form there are no reciprocating parts other then the connecting rods that swing back and forth a bit.
Click to expand...

Having a large heavy weight all spinning on the nose of a very short-coupled flying machine doesn't need the added complexity of reciprocating bits as well. !!

What is not mentioned in this video, which probably needs to be, is that this is an example of an early monosoupape engine = single valve.
The engine only has a single mechanical exhaust valve.
The inlet valve is that flap valve in the head of the pistons.
The fuel/air/oil mix is introduced into the crankcase, and finds its own way into the cylinders, mostly by centrifugal force.
Not very efficient - but it worked.
110 hp from 27 litres (in the later engines) is not a lot.
This engine type will not work at all if attempted to be used as a radial, that inlet valve system doesn't work if the fuel/air/oil isn't spun into the cylinders ?

Shame he can't spell rotary...
 
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