This document lists the original performance settings for the game and the changes I made.
In all cases the figure on the left is the original game and the figure to the right are
the corrections.If you have any questions please contact me on ICQ or by email instead of
posting to the message board.Thanks. jfarmer1@mindspring.com
I:Best Altitude.
AIRCRAFT         GAME FIGURE             CORRECTED FIGURE*
P-38H............414mph @ 22,000 ft.  -  408mph @ 25,800 ft.*(1)
P-38J............414mph @ 25,000 ft.  -  422mph @ 25,800 ft.*(2)
P-47C............433mph @ 34,000 ft.  -  433mph @ 30,000 ft.
P-47D............428mph @ 34,000 ft.  -  426mph @ 32,000 ft.*(3)
P-51B............440mph @ 22,000 ft.  -  440mph @ 30,000 ft.
P-51D............437mph @ 25,000 ft.  -  437mph @ 25,000 ft.
MkI Hurricane....316mph @ 6,000 ft.   -  316mph @ 19,000 ft.
Mk1a Spitfire....355mph @ 6,000 ft.   -  355mph @ 19,000 ft.
MkIXc Spitfire...408mph @ 21,000 ft.  -  408mph @ 25,000 ft.*(4)
MkXIVe Spitfire..448mph @ 16,000 ft.  -  448mph @ 26,069 ft.
Typhoon Mk1b.....417mph @ 13,750 ft.  -  406mph @ 18,000 ft.*(5)
Tempest V........435mph @ 17,000 ft.  -  435mph @ 17,000 ft.
Bf109E4..........348mph @ 14,000 ft.  -  348mph @ 14,560 ft.
Bf109G6..........386mph @ 16,000 ft.  -  386mph @ 22,640 ft.
Bf109K4..........452mph @ 16,400 ft.  -  452mph @ 19,685 ft.
FW190A8..........408mph @ 15,000 ft.  -  408mph @ 20,670 ft.
FW190D...........426mph @ 20,000 ft.  -  426mph @ 21,650 ft.
Me262A...........540mph @ 33,000 ft.  -  540mph @ 19,865 ft.

(1) The practical limits of the H model are defined by its older design intercoolers.
    These intercoolers were unable to properly cool the intake charge which degraded
    the maximum power output of the P-38H. As a result, the engines simply could not
    develop their max rating of 1,600 hp and Vmax suffered. Hence the lower rated top
    speed. The data comes from USAAF flight test results dated September, 1943. 

(2) The numbers for the P-38J come from testing performed by the USAAF Experimental
    Engineering Division. The test report, dated December of 1943 reflected a P-38J-10-LO
    taken from the production line at random. The engines were rated at 1,612 hp for the
    left engine and 1,619 for the right at 60.8 inches Hg. @ 3,000 rpm.

    Had the P-38L been modeled, which like the P-38J had the newer more efficient intercoolers,
    it would have been considerably faster. With the higher rated V-1710-F-30 engines
    making 1,725 to 1,750 hp each, the P-38L could pull up to 440 mph @ 25,650 ft. Tony LeVier
    reported 345.9 mph IAS (indicated airspeed) at 20,000 ft. This translates into 442 mph
    TAS (true airspeed). This P-38L-5-LO was fresh from the production line, unpainted and
    was not carrying any ammunition. Fully armed and fueled, Vmax would have been closer to
    425 mph at just 20,000 ft. LeVier was one of Lockheed's chief test pilots.

(3) The numbers come from Republic test data for the P-47D-25-RE. With the
    new HS paddle blade prop, climb increased to 3,235 fpm. However, the new prop was not
    able to restore the top speed of earlier models which fell mainly due to increased
    weight and drag.

(4) I have two sources that list the Mk.IXc as making its best speed at 25,000 ft. One is
    an undated test report from 8th Air Force Fighter Command and the second is published by
    Green & Swanborough. The USAAF report gives the Vmax as 407 mph, the other 408 mph.

(5) The Vmax speed of the Typhoon comes from several sources including USAAF testing in
    Britain, circa May, 1944. I believe this to be quite reliable.

As I said in my post to the message board.This is going to be an ongoing process.
As more data is discovered about the planes as well as the game it will be added.
Also,there are going to be adjustments to the RIP files to make them more compatible
with the structure of the game.As some of you have noticed and pointed out,the Bf109
series of planes are more prone to spinning now and they are much harded to recover.
This not accurate from a historical standpoint.
In my effort to increase the rudder response I decreased the yaw stability too much.
This has been corrected.After doing more digging and re-reading the notes Charles
Gunst sent me as well as long discussions with Paulo Morias,I found that what was 
labeled in the editor as power loading,was in fact horse power.The game appears to use
the Max.Horse power in WEP and the Max. sustained horse power at best engine altitude 
and adjusts the horse power for the altitude you are flying based on those 2 figures.
On the left you will see the Max.Sustained Horse power at best engine altitude for the real plane.
The next column is the Max.Horse Power in WEP at sea level.War Emergency Power systems
can only be used for a short period of time or over-heating and/or engine damage will
result.While the game does represent the use of WEP it does not represent it correctly 
because you can run the engine at full power far longer than you could with the actual 
aircraft.An example of this is the Bf109G6 which used Nitrous Oxide injection to boost
engine horse power.This system could only be used for about a minute or serious engine
damage would result.Most of the planes represented in the game used water/methynol
injection which could be used for approx. 15 minutes.The Hurricane and Mk1a Spitfire
did not have a WEP system but they could put their super-chargers in overboost but this 
could only be used for about a minute or the engine would be severly damaged.
As of yet,I don't think anyone has found the coding in the game that controls the engine
over heat time.In column 3 you will see the Max. sustained power figure the game used and 
in column 4 is the MAX.horse power in WEP figure the game used.Columns 5 and 6 are the
corrections I made,I used the Bf109E4 to figure the correctons.MicroProse sent me a .flt file
that was in text form and the figures for the Bf109E4 were correct.But you will note that 
most of the other planes are not exactly where they need to be.One anomaly you will notice 
are the P-47's.Both planes have the same rated HP but the original game had radically
different numbers.
I've arranged the planes by Max. WEP HP.Feel free to double check my numbers.

Multiply the Max. Sustained HP of the real plane by .000047 to get the corrected figure.
Multiply the Max. WEP HP of the real plane by .0000198 to get the corrected figure.
If you want to see what the game was using originally,simply divide the numbers by the factors 
above. 
(NOTE)-On the P-38 H and J models,the game appears to use the combined horse power of both engines.
This is why the numbers for these two planes appear to be very high compaired with the other planes.

II:Horse Power
                        ACTUAL AIRCRAFT
                   MAX.SUS.HP. MAX.WEP.HP   GAME SUS.HP. GAME WEP.  CORRECTED SUS.HP  CORRECTED WEP
Tempest V..........2,210 hp....2,420 hp.....-0.112161....-0.092341..-0.103870.........-0.047916
P-47C..............2,000 hp....2,300 hp.....-0.133345.....0.000000..-0.094000.........-0.045540
P-47D..............2,000 hp....2,300 hp.....-0.116109....-0.014652..-0.094000.........-0.045540
FW190D.............1,770 hp....2,240 hp.....-0.106513....-0.020167..-0.083190.........-0.044352
Typhoon Mk1b.......2,000 hp....2,200 hp.....-0.119955....-0.075781..-0.094000.........-0.043560
MkXIV Spitfire.....1,820 hp....2,050 hp.....-0.102428.....0.000000..-0.085540.........-0.040590
Bf109K4............1,810 hp....2,000 hp.....-0.106812....-0.022707..-0.085070.........-0.039600
Bf109G6............1,475 hp....1,800 hp.....-0.070532....-0.013965..-0.069325.........-0.035640                     
P-51D..............1,490 hp....1,720 hp.....-0.061533....-0.029333..-0.070030.........-0.034056
MkIXC Spitfire.....1,565 hp....1,710 hp.....-0.113410....-0.013845..-0.073555.........-0.033858
FW190A8............1,440 hp....1,700 hp.....-0.052613....-0.045117..-0.067680.........-0.033660
P-38H..............1,425 hp....1,450 hp.....-0.161650.....0.000000..-0.133950.........-0.057420 
P-38J..............1,425 hp....1,610 hp.....-0.105231.....0.000000..-0.133950.........-0.063756
P-51B..............1,380 hp....1,590 hp.....-0.060038....-0.017708..-0.064860.........-0.031482
Bf109E4............1,000 hp....1,175 hp.....-0.047052....-0.023275..-0.047052.........-0.023275
Mk1 Hurricane......1,030 hp......N/A........-0.033975.....0.000000..-0.048410..........0.000000
Mk1a Spitfire......1,030 hp......N/A........-0.041196.....0.000000..-0.048410..........0.000000

There are several of areas I'd like to address.One is propellors,I've been asked about the
Paddle blade props on the P-47D,the program will only accept certain values for the props.
The data I have,puts the paddle blade P-47D prop and the cuffed four blade Hamilton Standard
found on the P-51D in the same efficiency range as the five blade Rotol prop found on the 
MkXIV Spitfire.So I have used the same value as the Rotol prop for the P-47D and the P-51D.
The P-47C uses the standard prop.Another oddity about the game is that it lists the P-51B
as having a three blade prop but it carried a four blade prop.The B model used an Aero-Produces
four blade prop as well as the Hamilton Standard on the later production planes.I have changed 
the data to reflect the plane as having a regular four blade prop because of the availability
year listed in the game for the P-51B.The three blade prop was used on the P-51A with the 
Allison engine and was never used on a production Merlin engined Mustang.If anyone cares to 
look it up,the P-51B and the P-51C are virtually identical,the only real difference was that 
all B models were built at North American Aviation's Englewood California plant and the C model
was built in Dallas Texas.The P-51D was built at Englewood and the P-51K was built at Dallas.
There are two things that set the D model apart from the K.One is the shape of the canopy,the K
used a slightly taller canopy,and the other difference was that the K model used a Aero-Products
prop which made the K slightly inferior in performance to the D model due to a lower prop 
efficiency.

The next area is the Me262A,The best altitude and the service ceiling were too high for this 
airplane.I have made the adjustments to these figures.The early turbojet engines had a problem 
with compressor stalls and over-temps at high altitude as well as poor fuel metering systems.
As of yet,I have not been able to figure out what MPS used as a power factor for jet thrust.
The service ceiling for the game was listed as 44,000 ft,every source I've been able to find lists
it as 33,000 ft which given the performance of the early jets is a more believable figure. 

I also made corrections to the muzzle velocities and rates of fire for the guns,unfortunately 
no one has found a way to adjust the convergance of the guns yet.

The last area is rudder response,the only effective way to improve this was reducing the Yaw Stability
settings for the planes,because of the stall/spin recovery problems with the Bf109 series of 
planes I was forced to adjust it on a plane by plane basis.The planes with very low yaw stability 
were reduced by 25%,those with medium stability were reduced by 35% and those with high stability 
were reduced by 45%.This yielded good rudder response without making the planes unacceptbly unstable.
Also,I added the leading edge wing slats to the Bf109 series of planes.For the most part I stayed
away from doing anything to the flight models but the wing slats are historically correct.

Unless more factors are discovered that relate directly to performance this will be the final version.
As I said at the beginning,If you have any questions or comments please feel free to contact me.
Jim "WOLF" Farmer 


 


 





 


 

