Good discussions guys.
The P-38F and P38G had 300 gallons usable (total 306 gallons) in wing tanks while the P-38J and P-38L models had 410 gallons as the Bookie is describing. Drop tanks normally available to commanders in the field were 165 gallons (most commonly used) and 300 gallons (for VLR and ferry flights) not commonly used.
Range is often used interchangeably to describe combat range, i.e. a radius out and back, or total distance possible in a straight line. Not the same things at all obviously, and unfortunately because different sources use the term without defining which of the two meanings they were using, it causes great confusion.
Range numbers quoted on internet sources vary so using official AAF books is helpful, but not the absolute reality. Lockheed and their test pilots argued with the Air Force that their operating instructions were too conservative to get the best performance from the P-38 and Lindbergh proved he could double the endurance and range of the airplane over what the official operating instruction provided.
And that in reality is totally variable depending on altitude flown, speed flown, winds aloft, throttle settings, prop settings, mixture lean setting, aircraft loaded weight, fuel grade, condition of the airframe itself i.e. clean or how dirty, even whether the airframe was painted or left in aluminum.
However, CFS2 is a relatively simplified world and therefore we use a absolute numbers to model flight with.
So let's look at the official Operating Manual and the P-38 Tactical Chart. BTW that Tactical Chart is a late war official document as it incorporates operational lessons learned over the previous 2 years regarding RPM and mixture settings.
The Tactical chart shows the P-38 F&G (i.e. the 300 gal numbers) had a "Maximum Cruise" at 25,000 feet range/endurance of 600 miles and 2.2 hours. The Pilot's Operating Manual says maximum cruise with autolean mixture is 63 gals per hour per engine = 126 gals per hour. Maximum cruise was between 250 and 300 mph. So do the numbers correlate. 300 gallons/126 gph = 2.38 hours. If we use 275 miles per hour as an average we get 2.38 hours X 275 mph and we get 654 miles. That is close when none of the other variables above are not in the mix.
The Tactical Chart also says the P-38F P-38G had a "Long Range" at 10,000 feet range/endurance of 800 miles and 4.5 hours. The Pilot's Manual shows autolean could be adjusted down to a minimum of 31 gals per hour per engine = 62 gals per hour when setting the engines at 1600 RPM and 27 manifold pressure. So 300 gallons/62 gph = 4.83 hours. Again close. What speeds then are we talking about if we are getting to 800 miles? at 4.5 hours it is 177 mph and at 4.83 hours it is 165 mph. These figures match what Lindbergh was teaching to the P-38 Groups in the Pacific which eventually got back to officialdom and incorporated in the P-38 manuals and performance tables.
The P-38 J and P-38L numbers (i.e. the 424 gal numbers) check out in the same way.
So my clean configuration targets are between 600 to 800 miles distance for the P-38F and P-38G, and 840 to 1175 miles distance for the P-38J and P-38L at 10,000 feet.
For me, CFS2 air files are difficult to model because the game algorithms don't seem to accurately calculate the flight file values. Especially the fuel burn per hour calculations. That value in the flight files is nowhere near the rate used in the game, no matter what throttle, mixture and manifold pressures are used. Invariably a change to one value in the air file makes unwanted corresponding changes to other performance numbers. Or perhaps it's just me and my limited understanding of various aerodynamic values. Carefully inputting all of the real world values that can be identified from all available sources into the air file produces a plane's performance in the game that does not come close to the real aircraft's reported performance. Usually much too low. Very frustrating. I am left with jiggering values until I get the performance in the game that the real plane was supposed to have.
But so far, I have the P-38F and P-38G reaching 703 miles at 10,000 feet and keeping the reported top speed at 20,000 feet and at sea level. The P-38J and P-38L are being difficult. They are reaching 833 miles at 10,000 feet and keeping the reported top speed at 25,000 feet. However the sea level speed is about 20 mph too high. I'm still working on it but I am about ready to sacrifice the sea level speed and call it good enough for government work so I can move on with building the campaign. I still have about 20 missions to go to complete it.
Thanks for everyone's input.
The P-38F and P38G had 300 gallons usable (total 306 gallons) in wing tanks while the P-38J and P-38L models had 410 gallons as the Bookie is describing. Drop tanks normally available to commanders in the field were 165 gallons (most commonly used) and 300 gallons (for VLR and ferry flights) not commonly used.
Range is often used interchangeably to describe combat range, i.e. a radius out and back, or total distance possible in a straight line. Not the same things at all obviously, and unfortunately because different sources use the term without defining which of the two meanings they were using, it causes great confusion.
Range numbers quoted on internet sources vary so using official AAF books is helpful, but not the absolute reality. Lockheed and their test pilots argued with the Air Force that their operating instructions were too conservative to get the best performance from the P-38 and Lindbergh proved he could double the endurance and range of the airplane over what the official operating instruction provided.
And that in reality is totally variable depending on altitude flown, speed flown, winds aloft, throttle settings, prop settings, mixture lean setting, aircraft loaded weight, fuel grade, condition of the airframe itself i.e. clean or how dirty, even whether the airframe was painted or left in aluminum.
However, CFS2 is a relatively simplified world and therefore we use a absolute numbers to model flight with.
So let's look at the official Operating Manual and the P-38 Tactical Chart. BTW that Tactical Chart is a late war official document as it incorporates operational lessons learned over the previous 2 years regarding RPM and mixture settings.
The Tactical chart shows the P-38 F&G (i.e. the 300 gal numbers) had a "Maximum Cruise" at 25,000 feet range/endurance of 600 miles and 2.2 hours. The Pilot's Operating Manual says maximum cruise with autolean mixture is 63 gals per hour per engine = 126 gals per hour. Maximum cruise was between 250 and 300 mph. So do the numbers correlate. 300 gallons/126 gph = 2.38 hours. If we use 275 miles per hour as an average we get 2.38 hours X 275 mph and we get 654 miles. That is close when none of the other variables above are not in the mix.
The Tactical Chart also says the P-38F P-38G had a "Long Range" at 10,000 feet range/endurance of 800 miles and 4.5 hours. The Pilot's Manual shows autolean could be adjusted down to a minimum of 31 gals per hour per engine = 62 gals per hour when setting the engines at 1600 RPM and 27 manifold pressure. So 300 gallons/62 gph = 4.83 hours. Again close. What speeds then are we talking about if we are getting to 800 miles? at 4.5 hours it is 177 mph and at 4.83 hours it is 165 mph. These figures match what Lindbergh was teaching to the P-38 Groups in the Pacific which eventually got back to officialdom and incorporated in the P-38 manuals and performance tables.
The P-38 J and P-38L numbers (i.e. the 424 gal numbers) check out in the same way.
So my clean configuration targets are between 600 to 800 miles distance for the P-38F and P-38G, and 840 to 1175 miles distance for the P-38J and P-38L at 10,000 feet.
For me, CFS2 air files are difficult to model because the game algorithms don't seem to accurately calculate the flight file values. Especially the fuel burn per hour calculations. That value in the flight files is nowhere near the rate used in the game, no matter what throttle, mixture and manifold pressures are used. Invariably a change to one value in the air file makes unwanted corresponding changes to other performance numbers. Or perhaps it's just me and my limited understanding of various aerodynamic values. Carefully inputting all of the real world values that can be identified from all available sources into the air file produces a plane's performance in the game that does not come close to the real aircraft's reported performance. Usually much too low. Very frustrating. I am left with jiggering values until I get the performance in the game that the real plane was supposed to have.
But so far, I have the P-38F and P-38G reaching 703 miles at 10,000 feet and keeping the reported top speed at 20,000 feet and at sea level. The P-38J and P-38L are being difficult. They are reaching 833 miles at 10,000 feet and keeping the reported top speed at 25,000 feet. However the sea level speed is about 20 mph too high. I'm still working on it but I am about ready to sacrifice the sea level speed and call it good enough for government work so I can move on with building the campaign. I still have about 20 missions to go to complete it.
Thanks for everyone's input.
