Author Topic: Gnome Rotary Engine  (Read 1887 times)


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Gnome Rotary Engine
« on: January 30, 2013, 09:15:34 PM »
Did someone once ask about the valve arrangement on a rotary engine?

The Monosoupape had transfer ports from the crankcase, ( very vaguely ) like a 2-stroke.

The earlier engines had a 'valve in piston' doodah.

It may not have been on this forum, but Norman ( Ah, bless him  :LittleAngel: ) has sent me a pic. of the latter.

If it was not here, feel free to ignore me.

If it was here, you've got a piccy.    :Lol:

Dave BC


« Last Edit: January 30, 2013, 09:18:40 PM by Bluechip »


  • Guest
Re: Gnome Rotary Engine
« Reply #1 on: January 31, 2013, 09:30:36 AM »
Strange, I was only reading about this the other day. Lubrication was a total loss system, some of which was invariably ingested by the pilot. Castor oil is a laxative so it's suggested there were a few unexpected landings!  :Lol:  :naughty:

Offline BillTodd

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Re: Gnome Rotary Engine
« Reply #2 on: January 31, 2013, 10:26:21 AM »
Thanks Dave :)  (I think it was here somewhere! -- [edit] No it was on madmodders,7977.msg85710.html#msg85710 )

Aha I thought it'd need some kind of balancing on the intake valve, but didn't expect to see the use of balanced rocker gear and pull-rod operated exhaust valve (interesting how the designer has made use of the centrifugal force to allow him to reduce the size and force of the valve spring).

A quite elegant, if somewhat complex, design (typically French!)

« Last Edit: January 31, 2013, 10:36:25 AM by BillTodd »
wy omnibus Latinis taurus stercore?


  • Guest
Re: Gnome Rotary Engine
« Reply #3 on: January 31, 2013, 10:55:51 PM »
Arbalest ... Yes, I've read that. I wonder if it is actually true ?? 

Bill ... not only the French ... some German nationals even poked a rotary in a bike ...

Not an idea that would occur to me. Nicely finished bike though, once saw one years ago in Stuttgart ..

Dave BC


  • Guest
Re: Gnome Rotary Engine
« Reply #4 on: February 01, 2013, 09:02:45 AM »
"The lubrication system was a total-loss
type, with over two gallons of castor oil being sprayed
into the air during each hour of engine operation. This
explains why most rotaries were fitted with a threequarters
cowl ring, open at the bottom. The cowl
directed the spray of castor oil, along with sparks from
the exhaust, away from the flammable airplane
structure. In spite of these attempts to deal with the
excess lubricating oil, pilots were still subject to, and in
many cases the victim of, the well-known laxative
qualities of castor oil. Many unscheduled stops and offairfield
landings were credited to the call of nature.
Some pilots reportedly kept a flask of blackberry
brandy as an antidote to the effects of the oil"