Dear Paul.

1)  Is it true a Wankel can still power a plane in flight
up to half an hour even if it has lost all its coolant ?

2)  What is the effect, (both positive and negative)  on a
Wankel engine of too much 2-stroke oil in the fuel ?

Best regards.
Benjamin

No I don't think so. Maybe for a couple of minutes.
You should find a place to land as soon as it starts to overheat.
You should also install a cooling system pressure gage as that
can be an early warning sign. It is also useful for a preflight check
by manually pumping up the cooling system with air to 30 psi
(assuming you have a 30 psi pressure cap which you should) and
watching for a slow reduction in pressure indicating a leak.

It is very very important that you use the finest plumbing available
as the cooling system is critical. No automotive stuff. Don't nickel and
dime the cooling system. I recommend 1.5 inch OD aluminum tubing   where ever possible and silicone rubber  hose widely used in tractor
trailer trucks for connections. Make sure the tubes have beads on them.
Tubing beaders can be bought from several sources. Also use 50 50 premix
coolant and  change it out every two years for new.

There are special hose clamps called constant tension.
These have springs in them that allow
them to expand and contract as the aluminum tubing expands and
contracts with heat. They are made by Breeze and sold in truck
stops. WW II P51's generally used two clamps per connection. That
is two on each end of the hose.

In addition for the finest connections possible buy
some of Jeff's Wiggins couplings. These are widely used on
airliners and Formula 1 race cars. The racers pay over $100
each but Jeff makes them and sells for a real low cost
$40 per set.

Scroll down to the bottom of the first page on
http://www.rotaryeng.net

I have written a book on Wankel cooling sold by AC Spruce.
Every now and then we have a direct special.

Up to 4 ounces per gallon of 2 cycle oil are OK. More than that
and you could foul the plugs. Less than an ounce per gallon and
you risk wearing out the apex seals and or overheating the apex
seal springs causing them to fail.

Paul Lamar


Thank you Paul.  I appreciate that.
Benjamin