Crumpp

I thought your discussion was trying to be meaningful and did not realize you changed the subject to some off the wall maximum continuous analysis. Best range is a specific point on the drag curve of the design. It was 280mph TAS is the Mustangs Best range Speed at 20,000 feet. Running the engine at settings that do not put you on that spot are totally irrelevant to the topic. That is why maximum range is its own chart and why the fuel planning was done. You are spamming my thread. I know you think you are raising some good points but you are really not.

Not the same column used for my flight planning. Irregardless you are spamming my thread. Go start another on fuel planning.

Ok now we are getting somewhere. 1.55 - .2 - 1.35 to ballpark the aircraft's CLmax. That is within the Mtt Bf-109G polar.

You are killing me. Now, do you understand Aspect Ratio has no effect on 2D airfoil data? Why is that? 2D airfoil data has an infinite Aspect Ratio.

The topic is the lift polar for the Bf-109K4 and using the 2D data for the airfoil.

Of the wing Hummingbird...NOT THE AIRFOIL POLAR.

It is True Airspeed not Indicated Airspeed. Please STOP Spamming my thread with this stuff. The thread is not entitled "Teaching to Fuel Plan".

I agree and further proof it is the polar...beside being labeled that! :P

It is not due to the aspect ratio increase. AR allows a reduction in the 3Dimensional wing drag due to lift which means the wing can climb higher on the 2D airfoil polar. AR ratio will not increase the 2D polar Clmax.

The chart is labeled, Coefficient of Lift vs Angle of Attack Lift to Drag Ratio Coefficient of Lift vs Coefficient of Moment

The chart you are using only calculates time based on the cruise fuel available not the total fuel in the tanks.

I understand that you are convinced of that and are going to continue to spam my thread without proof. Can we move on?

Bf-109G series data is posted in this thread. I used 1.41 based on radiator flap position of 15 degrees.

] Not for World War II fighters..... Only for very very low aspect ratio designs like the F-104 Starfighter. It is not a factor or a contributor for the Aspect Ratio range we are talking about.

Ok, these are planning charts used by the pilots. There use follows specific guidelines and it is not simply divide the number by the amount of fuel in the full tank. It is beyond the scope of this thread to teach you flight planning. http://flighttraining.aopa.org/magazine/2002/July/200207_Features_Learn_What_You_Burn.html Bottom line up front is your simplistic calculation is not correct.

It was fitted with both slats, as well as without slats and fences. V24 was the test bed for the Bf-109F series and the airframe used to research the airframe changes brought about in that series. It is the airframe they tinkered with to confirm design assumptions later incorporated into the Bf-109F series Aspect Ratio effects our Drag due to lift and not our CLmax. CLmax is purely a function of the 2D airfoil and the Bf-109 series has the same airfoil. http://m-selig.ae.illinois.edu/ads/aircraft.html The root airfoil remains unchanged throughout the Bf-109 series. The tip airfoil was changed in the Bf-109F series and remained untouched for the rest of the designs life. That is why i posted the G series polar and it is more representative. The V24 is good for trend information only and not specifics. Clmax of 1.6 is not appropriate IMHO. It is not reflected on any polar and most damning is not used by Mtt. Again, they use 1.4 only out to a single decimal place for the Bf-109E series. I used 1.41 based on radiator flap position of 15 degrees. CLmax will change based on radiator flap position.

Checking out fuel planning against the chart.. At 20,000 feet we are able to travel at 280mph TAS. With 120 available gallons we can fly 640 air miles according the maximum range chart. 640 Air Miles / 280 Mph TAS = 2.28 hours of endurance Less than 1% error...

No it does not leave the Mustang 5.3 hours on 184 gallons of gas. Look at the P-51D's Take Off and Landing charts and plan the fuel consumption. Total internal fuel capacity (Wing Tanks) = 184 gallons. Yes there is unusable fuel included in that figure but it will only shorten our endurance slightly. First flight, Take Off, climb to 20,000 feet, Descend, Land. This does not include go-around or any reserve fuel. Taxi, Take Off, and Climb fuel = 33 Gallons Descent, Landing, and Take Off = 33 Gallons 66 gallons total to get up and get down from 20000ft. 184 gallons - 66 gallons = 118 gallons to fly around with... At our most maximum fuel efficiency, conducting a perfect flight we need: We are burning 48 gallons per hour at 20,000 feet. The is the LEAST amount of fuel the aircraft is capable of consuming and remain airborne. 118/48 gallons = 2 Hours and 27 minutes of doing nothing. Let's compare that to the BMW801D2 20,000 feet = ~ 6Km (6.09Km so we are a little conservative in favor of the Mustang) A little extrapolation puts our BMW801D2 FW-190A8 at 2 hours and 10 minutes for the same flight profile. A advantage of 17 minutes or 13.5 gallons of fuel extra which equal = 97lbs of weight. 97 lbs of weight = ~.4 degrees/sec rate of turn gain. It does not make a practical difference. The Dora would be much closer in the fact the Jumo 213 consumes less fuel than the BMW801. The BMW801 uses ~450liters and hour while the Jumo213 uses ~375liters and hour at 6 Km.

The 2.1 hour figure is after fuel used for take off, taxi, climb out for the FW-190A8. Where your 5.4 hr calculation assumes the P-51 burns no fuel to get to altitude in taxi, take off, and climb.

Ok, standing by for the results! The first fuel load on a P-51 is the main tanks (wing tanks IIRC 75% on the slider).

You can and it is not a realistic thing either. Nobody takes reduced ammunition but fuel is ok..... :huh:

They enforce historical load outs for weapons, why not fuel? Give us the option to enforce it. It keeps the situation developing where we have one side spawning with drop tanks vs another section launching with greatly reduced fuel loads. It gives the server and mission editor a universal setting to help prevent abuse.

I think some perspective on just how thirsty these aircraft are might help to see the futility of partially filling tanks. 29 gallons of gas are required to go from the ramp to the 1000 feet AGL. Getting from the Ramp to 20,000 feet consumes 67 gallons of fuel for planning purposes. That means you reach 20,000 feet ready to fight and your fuselage tank is almost empty. You are also only ~25 miles from where you took off! Most of these maps, 25 miles is not that large a distance! The USAAF standard planning was 20 minutes for Combat. That is 5 minutes at War Emergency Power and 15 Minutes at Military Power. That consumes 61 gallons of gas for 33% of a P-51's internal fuel load. In World War II, That left a P-51 pilot with 1 hour and 11 minutes of cruising time at maximum range settings. That is not much when you are fighting over an area it took 2 hours of flying to get there. You can see why the "long range fighter program" was such a difficult engineering feat and why external fuel tanks were the norm.

That is what they did or tried to do. Understand that combat is very fuel thirsty business. Military aircraft are governed and regulated. You have to take things like reserve fuel, your mission is "dispatched". That means you as the pilot and an operations guy on the ground have joint responsibility for the flight. He has to approve and sign off on the flight as do you. You check his work and he checks yours..... That is one of the duties of the Operations Officer in the Squadron. You simply will not get a flight approved which means no fuel release, no ground support, etc.. Believe me, aside from the fact it is just not going to happen because it violates basic fuel planning, you WANT to take things like reserve fuel. Aircraft divert and deviate from the "plan" all the time.

Yes Solty it was not an issue when I did not play the game or was unaware of it. Is that surprising to you somehow? I have explained that it ruins cockpit immersion because it introduces thinking that the machines operators would not use. Why are so scared of allowing people to have a choice?