1. L

    Alternate Bristol Engine Development (Mercury & Pegasus)

    I'm considering Kaiserreich-esque Alt Hist timeline where Canada + a bunch of British exile engineers have to build aero engines -- for speed of development, reliability, and simplicity they just develop the Bristol Mercury/Pegasus, avoid sleeve valves and stick with poppet valves, and also go...
  2. Z

    Air cooled inline engines - a missed opportunity?

    I was thinking of air cooled inline engines, that in principle could combine the low frontal area of liquid cooled inlines, the lack of a heavy and battle damage prone radiator, and the simplicity of air cooling. There were some developments in this direction in the interwar years, though as I'm...
  3. Howard Gibson

    Break Mean Effective Pressure

    We keep discussing engine performance. I am researching this in WWII aircraft and I ought to share stuff. I won't go into the math, but the work done by a cylinder doing a single stroke is the volume swept by the piston, multiplied by the presumably constant pressure. Power is among other...
  4. CN AK12

    about IJN DB601 performance (A6M1 special)

  5. S

    Looking for primary sources regarding engine performance and statistics

    I've been trying to compile data for a game project I'll probably never complete, but I need primary information on the for various aircraft engines in the PTO for it. I got very lucky to start with, in finding scores of useful sheets from Pratt&Whittney themselves right here. However, there's...
  6. Baball

    Aircraft Engines of the World, 1945 and Aircraft Diesels, 1940 by Paul H. Wilkinson

    Two reference books authored by Paul H. Wilkinson, containing data of numerous aircraft gasoline and diesel engines. The book about diesels is a russian translation of the guide.
  7. K

    Unknown Engine dug out from Japanese field

    Hi all, I am new to here and I would like to get help to sort out what engine is this. Friend of mine living in Japan who has small grape field has dug out a rusted WW2-era aircraft engine 5 months ago, with several other metal fragments from same era. Engine's condition is not so good, rusted...
  8. R

    How did piston engines get so powerful

    If you compare the BMW IV engine of the 1920s to the DB 6xx series, you see that power almost tripled, for more or less the same displacement. What were the main technical improvements that made this possible? Was it just/mainly the supercharger or another main improvemnt which drove the...
  9. C

    Unsynchronized German Engines

    This is my first post on the forum and I'm far from aircraft aficionado, but I do understand the general principal of engine synchronization on propeller planes. As far as I know, it's more of a general comfort issue to the passenger to have synced engines rather than anything aerodynamic. My...
  10. M

    Italians with higher hp radials?

    Almost all Italian fighters of the early war years were radials, with the license built DBs available later, they became inlines, eg MC 200 to 202, G 50 to G 55. Do you think the Italians would have stuck with radials if they had engines of sufficient power? Could they have used the BMW 801...
  11. fastmongrel

    Licence built DaimlerBenz V12s, what was the problem

    Another thread started me on this train of thought. What was it that meant that the licenc built DB engines never seemed to live up to the engines built by the Germans. I can find three companies Alfa Romeo, Kawasaki and Aichi that built DB engines and plenty of claims they werent as good as...
  12. tomo pauk

    1940: the top 3 engines in service

    What would be the top three engines in air forces of the world, in service, in the key year of 1940? Whether inline/V-12 or radial, big or small, with provision for prop shaft gun or not. Please tell a bit about your picks. Flag waving is discouraged :)
  13. syscom3

    Wright turbo compound engines. Fact book.

    Everything you need to know about the Wright turbo compound engine. http://www.enginehistory.org/Wright/TC%20Facts.pdf
  14. fubar57

    Airspeed A.S.39 Fleet Shadower

    Ok, so the French weren't the sole proprietors of butt ugly aircraft. The first I've heard of this monstrosity... Knowing exactly where your enemy is lurking is one of the greatest advantages a military commander can have over his opponent. During World War Two, while the navies of the...
  15. J

    CAC CA.26 and CA.27 (all versions) Avon Sabre

    Well known of the Koreanwar is the North American Sabre. This type was build under licence in Canada as the Canadair CL-13 Sabre.But more interresting is the Australian build versions.There first prototype was the CAC Ca-26 and the production versions the CAC Ca-27 Mk.30, Mk.31 and Mk.32, based...
  16. D

    Junkers 390 with jet engines?

    Would this modification have been possible? What if the Junkers had not used 6 BMW-801G engines but in fact had used eight Junkers Jumo 004 engines? Now this would defeat it's purpose of the Amerika Bomber program the RLM had in mind, but imagine what it could have been used for on the fronts at...
  17. W

    Performance of He177 with Jumo 222s?

    Does anyone have any idea what the spec of a He177B with four Jumo 222s was? It might have been tested with it: https://en.wikipedia.org/wiki/Heinkel_He_177#Further_development-the_Heinkel_He_177B If it were, what sort of range, speed, and altitude could it have had with the Jumo 222 E/F...
  18. gjs238

    Effects of multi-speed superchargers (or lack of the same)

    Much has been discussed here of multi-stage superchargers, but less of multi-speed single-stage superchargers. The DB engines used a hydraulic fluid coupling with a barometric control to achieve multi-speed drive with a seamless power curve. Other engines featured multiple speeds, kinda like a...
  19. Elmas

    Engines coupled as in DB 606 and DB 610

    I'm a structure man, not an engine man so there's one thing that I don't understand. AFAIK the coupling of the two engines was trough a mechanical device and my question is: how can two engines coupled by a mechanical device based on gearwheels have a tuning so identical to exactly give the...
  20. W

    US jet engine development without WW2?

    If there was not a WW2, say Hitler dies of a heart attack or something like that pre-1939, how long would it take the US to develop jet engines without British assistance? They were pretty behind compared to the Europeans and needed British developments to jump start their own program in 1943.