I was in the San Diego air museum on Sunday and took
       a picture of a very cosmetic RR Merlin. Good picture of the
       air to water intake heat exchanger designed by "Not Much Of
       An Engineer"  Stanley Hooker.  It made the Merlin far
       superior to the Allison at high alts.

       That gave me an idea. What the high power Wankel needs
       is an air to water heat exchangers instead of an intercooler.
       Conventional intercoolers require a lot of bulky air plumbing.

       The  well integrated Merlin version is about one cubic foot for 1500 HP
       so something like half of that ought to work for a 650
       HP Wankel. Then you will need a another small water pump
       and another small rad.

       All you guys with cell phones may have trouble seeing this with more than
       one picture. Android is not up to it. I can't wait to get Linux in
       my new $125  (Walmart) Pumpkin Phablet :-)

       Paul Lamar


       Picture of the magazine cover looks exactly the same from my pc and my android.
       What am I missing?
       Narfi Willem

       My mistake. The other seven pictures.
       I'll try that again. Here they are.

       Paul Lamar

Was it the air to water intercooler that made the Merlin altitude performance better?
The Merlin quickly incorporated two speed supercharging and then two stage. The USAAC had decided that turbocharging was more fuel efficient so dictated that.


The early Allison retained the single stage single speed supercharger longer which perpetuates the altitude performance history. The aircraft manufacturers found integrating the turbocharger difficult and problematic. Exhaust plumbing  and finding a suitable turbocharger mounting location limited integration. Some R&D designs performed admirably although late in the war.


Allison also was developing the turbocompound engine as the war concluded. The development of turbine engines especially for larger aircraft and military fighters relegated recip engines to history books and smaller GA designs.

When you see a 4500 HP Allison turbine with gearbox almost beside a Cooper Besmmer V16 of the same HP, the size difference is amazing. The Cooper valve covers stacked take up as much or more volume than the Allison with gearbox.

Dale Davies

Do you have that picture Dale? Can you scan it and sent it?

Paul Lamar


       The Rotary Engine free News Letter. Powered by Linux. If you want off
       the list PLEASE let me know and I will remove  you.  ACRE NL web
       site. http://www.rotaryeng.net You Tube http://tinyurl.com/beqqxas
       Copyright 1998-2017 All world wide rights reserved.