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Tachyon1000
01-06-2006, 03:44 PM
Level Acceleration Performance Tests

Intro

In an effort to derive a climb schedule via techniques actually used for that purpose, I performed level acceleration tests to determine the specific excess power that may be used to determine best rate of climb. In the modern total energy perspective of flight theory it is known that power for acceleration or power for climb are essentially the two aspects of the same thing, a balance of kinetic and potential energy derived from lift and engine power and that of drag. Therefore one can merely fly level at a specific altitude and a specific power setting and determine the maximum specific excess power and the speed associated with it.

The total energy state of the aircraft is merely the sum of its potential and kinetic energy. Specific excess power is merely the derivative of the total energy state with respect to time. The power is excess in that it is power in excess of that needed for level flight or merely more than drag on the airplane. The conceptual formula is simple:

Ps = dh/dt + (Vt/g)(dVt/dt)

where Ps is specific excess power in ft/sec, h is altitude in feet, Vt is true airspeed in ft/sec, and g is the gravitational acceleration constant (32.3 ft/sec^2).

Any specific excess power determined via level acceleration tests is true only for the specific conditions it was tested under, i.e. altitude, temperature, weight, thrust, etc., however an adjustment can be made for other weight conditions.
The specific excess power is directly translatable into rate of climb and maximum Ps is the same as best ROC for the specific altitude and speed.

More detailed info on theory and procedures can be found here:

http://flighttest.navair.navy.mil/unrestricted/FTM108/c5.pdf

http://www.dfrc.nasa.gov/Education/OnlineEd/Intro2Flight/nasaccel.html



Procedure

Missions were created in FMB for target test altitude. I used Crimea map, P-38J, 75% fuel, 54€ of manifold pressure, auto radiator. Basically, the procedure is to establish level flight for target altitude at the lowest power setting needed for level flight and add throttle to desired level (here 54€ MP), and maintain level flight within 300ft of target altitude. Data collected with UDPGraph was IAS, TAS, MP, altitude, and time between readings. Poll time for UDPGraph was set at 500msec. Inputs (dh/dt and dVt) to the Ps equation were estimated via the difference between altitude and TAS between data collection intervals divided by the poll interval recorded by UDPGraph. I ran at least four trials for altitudes of 10,000, 15,000, 20,000 and 25,000 ft. None for 35,000 ft as the P-38J cannot maintain correct manifold pressure at this altitude, and only 1 trial of 5,000 ft as climb performance is not terribly at issue at this altitude.

Results:

Mean results of the tests are as follows:

5,000 ft ROC = 3068.21 ft/min IAS = 182.93 mph

10,000 ft ROC = 2843.04 ft/min Weight Adjusted ROC = 2900 ft/min
IAS = 176.01 mph

15,000 ft ROC = 2696.1 ft/min Weigh Adjusted ROC = 2771.60 ft/min
IAS = 167.73 mph

20,000 ft ROC = 2523.9 ft/min Weight Adjusted ROC = 2607.19 ft/min
IAS = 158.02 mph

25,000 ft ROC = 2201.55 ft/min Weight Adjusted ROC = 2274.2 ft/min
IAS = 146.55 mph

To explain the weight correction, Ps and thus the ROC were determined for a plane of 75% fuel weight, however the pilots€ manual shows fuel used to obtain the altitude, thus the plane is lighter at higher altitudes. I determined a weight for a P38L with 75% fuel with a base weight of 14,400 lbs + 6.5 pounds per gallon of fuel indicated by UDPGraph for 75% fuel, that weight being 16318.4 lbs. To determine the weight that the plane would be as per the pilots€ manual climb schedule I merely subtracted a weight equal to the weight of fuel used in the chart from the weight for the plane at 75% fuel. Weight Adjusted Ps was then determined by a simple proportional relation:

the calculated Ps/the 75% fuel plane weight = the weight adjusted Ps/the weight that the plane should be as per the climb schedule.

http://www.geocities.com/grantsenn/NACA_TESTING/P38/WR_GCS00001/FIG01.jpg
Fuel usage is given by the above chart.



Below is a ROC curve that TAGERT has presented elsewhere. It claims to give rates of climb for the indicated altitudes for a P-38J climbing optimally at 54 inches of manifold pressure (curve labeled 54€ Pilots Manual Data). The curve labeled €œin-game DeviceLink Data€ is from TAGERT€s own test data, not mine.
http://i32.photobucket.com/albums/d35/ivankautter/P38J_ROC_TAGERT.jpg

Interpolating from this graph, we arrive at these ROC values for the following altitudes from the Pilots Manual Data:

5,000 ft ROC = 3000 ft/min
10,000 ft ROC = 2750 ft/min
15,000 ft ROC = 2600 ft/min
20,000 ft ROC = 2400 ft/min
25,000 ft ROC = 2050 ft/min

Comparing these interpolated values to those obtained in the level acceleration tests, we can see that the P-38J at 54€ MAP in-game actually exceeds what I am assuming is the real world performance of the P-38J.


Conclusion:

The P-38J meets or exceeds the interpolated values from the graph above that TAGERT has referenced as a conservative estimate of the climb performance of the P-38J during the climb check. This is an independent confirmation of the flight performance of the J that is not dependent upon the performance of the pilot in the climb check.

Tachyon1000
01-06-2006, 03:44 PM
Level Acceleration Performance Tests

Intro

In an effort to derive a climb schedule via techniques actually used for that purpose, I performed level acceleration tests to determine the specific excess power that may be used to determine best rate of climb. In the modern total energy perspective of flight theory it is known that power for acceleration or power for climb are essentially the two aspects of the same thing, a balance of kinetic and potential energy derived from lift and engine power and that of drag. Therefore one can merely fly level at a specific altitude and a specific power setting and determine the maximum specific excess power and the speed associated with it.

The total energy state of the aircraft is merely the sum of its potential and kinetic energy. Specific excess power is merely the derivative of the total energy state with respect to time. The power is excess in that it is power in excess of that needed for level flight or merely more than drag on the airplane. The conceptual formula is simple:

Ps = dh/dt + (Vt/g)(dVt/dt)

where Ps is specific excess power in ft/sec, h is altitude in feet, Vt is true airspeed in ft/sec, and g is the gravitational acceleration constant (32.3 ft/sec^2).

Any specific excess power determined via level acceleration tests is true only for the specific conditions it was tested under, i.e. altitude, temperature, weight, thrust, etc., however an adjustment can be made for other weight conditions.
The specific excess power is directly translatable into rate of climb and maximum Ps is the same as best ROC for the specific altitude and speed.

More detailed info on theory and procedures can be found here:

http://flighttest.navair.navy.mil/unrestricted/FTM108/c5.pdf

http://www.dfrc.nasa.gov/Education/OnlineEd/Intro2Flight/nasaccel.html



Procedure

Missions were created in FMB for target test altitude. I used Crimea map, P-38J, 75% fuel, 54€ of manifold pressure, auto radiator. Basically, the procedure is to establish level flight for target altitude at the lowest power setting needed for level flight and add throttle to desired level (here 54€ MP), and maintain level flight within 300ft of target altitude. Data collected with UDPGraph was IAS, TAS, MP, altitude, and time between readings. Poll time for UDPGraph was set at 500msec. Inputs (dh/dt and dVt) to the Ps equation were estimated via the difference between altitude and TAS between data collection intervals divided by the poll interval recorded by UDPGraph. I ran at least four trials for altitudes of 10,000, 15,000, 20,000 and 25,000 ft. None for 35,000 ft as the P-38J cannot maintain correct manifold pressure at this altitude, and only 1 trial of 5,000 ft as climb performance is not terribly at issue at this altitude.

Results:

Mean results of the tests are as follows:

5,000 ft ROC = 3068.21 ft/min IAS = 182.93 mph

10,000 ft ROC = 2843.04 ft/min Weight Adjusted ROC = 2900 ft/min
IAS = 176.01 mph

15,000 ft ROC = 2696.1 ft/min Weigh Adjusted ROC = 2771.60 ft/min
IAS = 167.73 mph

20,000 ft ROC = 2523.9 ft/min Weight Adjusted ROC = 2607.19 ft/min
IAS = 158.02 mph

25,000 ft ROC = 2201.55 ft/min Weight Adjusted ROC = 2274.2 ft/min
IAS = 146.55 mph

To explain the weight correction, Ps and thus the ROC were determined for a plane of 75% fuel weight, however the pilots€ manual shows fuel used to obtain the altitude, thus the plane is lighter at higher altitudes. I determined a weight for a P38L with 75% fuel with a base weight of 14,400 lbs + 6.5 pounds per gallon of fuel indicated by UDPGraph for 75% fuel, that weight being 16318.4 lbs. To determine the weight that the plane would be as per the pilots€ manual climb schedule I merely subtracted a weight equal to the weight of fuel used in the chart from the weight for the plane at 75% fuel. Weight Adjusted Ps was then determined by a simple proportional relation:

the calculated Ps/the 75% fuel plane weight = the weight adjusted Ps/the weight that the plane should be as per the climb schedule.

http://www.geocities.com/grantsenn/NACA_TESTING/P38/WR_GCS00001/FIG01.jpg
Fuel usage is given by the above chart.



Below is a ROC curve that TAGERT has presented elsewhere. It claims to give rates of climb for the indicated altitudes for a P-38J climbing optimally at 54 inches of manifold pressure (curve labeled 54€ Pilots Manual Data). The curve labeled €œin-game DeviceLink Data€ is from TAGERT€s own test data, not mine.
http://i32.photobucket.com/albums/d35/ivankautter/P38J_ROC_TAGERT.jpg

Interpolating from this graph, we arrive at these ROC values for the following altitudes from the Pilots Manual Data:

5,000 ft ROC = 3000 ft/min
10,000 ft ROC = 2750 ft/min
15,000 ft ROC = 2600 ft/min
20,000 ft ROC = 2400 ft/min
25,000 ft ROC = 2050 ft/min

Comparing these interpolated values to those obtained in the level acceleration tests, we can see that the P-38J at 54€ MAP in-game actually exceeds what I am assuming is the real world performance of the P-38J.


Conclusion:

The P-38J meets or exceeds the interpolated values from the graph above that TAGERT has referenced as a conservative estimate of the climb performance of the P-38J during the climb check. This is an independent confirmation of the flight performance of the J that is not dependent upon the performance of the pilot in the climb check.

Jetbuff
01-06-2006, 03:59 PM
S! on one hell of a presentation!

Ratsack
01-06-2006, 04:06 PM
Interesting post, Tachyon. Good work.

Do you know what happens if you try to match your calculated climb rates in-game?

cheers,
Ratsack

JG5_UnKle
01-07-2006, 10:08 AM
Interesting read, piccies are down though - I guess they were moved http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Tachyon1000
01-07-2006, 06:07 PM
Pics look fine to me. Perhaps mine are cached in my browser. As to acheiving this climb schedule, there are two difficulties. One, I am a sucky pilot. This is precisely why I chose this testing technique as it relies very little on the skill of the pilot to manage speed and angle of attack. Two, the speeds derived from the test are not necessaryily the right ones for that altitude. While I was able to make an adjustment for the weight of the aircraft to derive its performance under the expect fuel weight, I was unable to find how one goes about adjusting the speed to meet the expected fuel conditions. If one were to climb at the speeds I posted, the climb performance in terms to time to climb would be less than expected. What these tests suggest is that the J is fine with respect to its climbing ability.

Tachyon1000
01-07-2006, 06:11 PM
The pics were indeed removed. I wonder why? If someone can tell me where I can host them, I have my own local copies on my machine of course. Pics hosted now at photobucket. I have no idea what the bandwidth limits are.

bolillo_loco
01-08-2006, 06:40 AM
You do realize that the chart from the pilot's manual uses two very different methods to achieve said data from your own. Full take off weight is more than 1,000 lbs heavier than your own and the rate of climb is from a standing start not from level flight.

Tachyon1000
01-08-2006, 10:39 AM
I used the 75% fuel load as that is the one suggested by TAGERT himself as valid for such testing considering the amount of fuel used in warm-up and taxi.

Your other question suggests you have not understood what I have done or the procedure used. I don't feel obligated to explain it to you as the documentation is readily available. If you had read and understood it, you would not ask such a question.

Brain32
01-08-2006, 10:53 AM
Excellent presentation http://forums.ubi.com/images/smilies/25.gif http://forums.ubi.com/images/smilies/25.gif http://forums.ubi.com/images/smilies/25.gif
THX!

bolillo_loco
01-08-2006, 11:57 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Tachyon1000:
I used the 75% fuel load as that is the one suggested by TAGERT himself as valid for such testing considering the amount of fuel used in warm-up and taxi.

Your other question suggests you have not understood what I have done or the procedure used. I don't feel obligated to explain it to you as the documentation is readily available. If you had read and understood it, you would not ask such a question. </div></BLOCKQUOTE>

I'm not sure why your post was so anti-social in nature and directs hostility towards me. While you may not feel obligated to explain to you, I don't feel obligated to insult you. Your post has been challenged for its validity. Your calculations neither prove or disprove anything. Any body with a basic grasp for dazzling people with mathmatical calculations that few if any understand could prove that: bumble bees cannot fly and the "magic bullet" that killed Kennedy did in fact cause 8 other entry holes. It proves little. I thought you might want to know that a gallon of gasoline weighs 6 pounds not 6-1/2 pounds.

Also the data provided by the Pilot's manual is for a Lightning at 100% fuel not 75%.

More over, with this statement, quote: "Missions were created in FMB for target test altitude. I used Crimea map, P-38J, 75% fuel, 54€ of manifold pressure, auto radiator. Basically, the procedure is to establish level flight for target altitude at the lowest power setting needed for level flight and add throttle to desired level (here 54€ MP), and maintain level flight within 300ft of target altitude." leads me to believe that you began your climbing tests while in level flight. This is not the case of the real life data collected by Lockheed, the USAAC, and other aircraft manufacturers. My question was basic and simple enough, Did you obtain your data from a level flight or did you begin from a ground start at zero air speed? Further more, 25% fuel is not used for warm up and taxi. The manual clearly states that 50 gallons should be deducted for warm up, taxi, and take off, but in no way does it amount to 25% of the internal fuel load. It also considers take off, not just warm up and taxi.

Once again, I'm not challenging your calculations, but the manner in which you obtained your in game data.

I can provide calculated data to show the P-38J and P-38L did in fact climb at 4,500 - 5,000 + feet per minute. This was all done by teams Lockheed techs, which both collectively and individually undoubtedly have a more extensive education in both aircraft and mathmatics than you do. Does this mean that the Lightning could do it? No because calculations are subject to a lot of errors and rarely reflect what the real subject could in fact do.

Tachyon1000
01-08-2006, 12:21 PM
Again, you don't understand the procedure, because you have not read it. You post to challenge what you don't understand because you disagree with the implications of the results.

OldMan____
01-08-2006, 12:43 PM
Well do not disregard his knowledge only because he does nt work at lockheed. Modern theories might have aevolved quite a bit, so that mistakes from past are correct now ( not implying that any one is right here).


At that time many engineers tought It was impossible to pass the sound speed with a self propelled object.... they were wrong.

So this data deserves carefull annalysis.

faustnik
01-08-2006, 01:12 PM
In relative terms, the P-38J seems to climb very well. The Fw190A6 can't escape by climbing even at high speed. The Bf109G2 can, but, the G6 has trouble. This sounds about right to me. I know things should be correct in absolute terms, but, relative correctness is good. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Ratsack
01-09-2006, 03:08 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by bolillo_loco:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Tachyon1000:
I used the 75% fuel load as that is the one suggested by TAGERT himself as valid for such testing considering the amount of fuel used in warm-up and taxi.

Your other question suggests you have not understood what I have done or the procedure used. I don't feel obligated to explain it to you as the documentation is readily available. If you had read and understood it, you would not ask such a question. </div></BLOCKQUOTE>

I'm not sure why your post was so anti-social in nature and directs hostility towards me. While you may not feel obligated to explain to you, I don't feel obligated to insult you. Your post has been challenged for its validity. Your calculations neither prove or disprove anything. Any body with a basic grasp for dazzling people with mathmatical calculations that few if any understand could prove that: bumble bees cannot fly and the "magic bullet" that killed Kennedy did in fact cause 8 other entry holes. It proves little. I thought you might want to know that a gallon of gasoline weighs 6 pounds not 6-1/2 pounds.

Also the data provided by the Pilot's manual is for a Lightning at 100% fuel not 75%.

More over, with this statement, quote: "Missions were created in FMB for target test altitude. I used Crimea map, P-38J, 75% fuel, 54€ of manifold pressure, auto radiator. Basically, the procedure is to establish level flight for target altitude at the lowest power setting needed for level flight and add throttle to desired level (here 54€ MP), and maintain level flight within 300ft of target altitude." leads me to believe that you began your climbing tests while in level flight. This is not the case of the real life data collected by Lockheed, the USAAC, and other aircraft manufacturers. My question was basic and simple enough, Did you obtain your data from a level flight or did you begin from a ground start at zero air speed? Further more, 25% fuel is not used for warm up and taxi. The manual clearly states that 50 gallons should be deducted for warm up, taxi, and take off, but in no way does it amount to 25% of the internal fuel load. It also considers take off, not just warm up and taxi.

Once again, I'm not challenging your calculations, but the manner in which you obtained your in game data.

I can provide calculated data to show the P-38J and P-38L did in fact climb at 4,500 - 5,000 + feet per minute. This was all done by teams Lockheed techs, which both collectively and individually undoubtedly have a more extensive education in both aircraft and mathmatics than you do. Does this mean that the Lightning could do it? No because calculations are subject to a lot of errors and rarely reflect what the real subject could in fact do. </div></BLOCKQUOTE>

What he's not explaining is that the test method involves level flight only. There are no climbs per se.

cheers,
Ratsack

Viper2005_
01-12-2006, 08:28 PM
This approach seems reasonable but experimental error should be accounted for.

It relies upon the assumption that level acceleration is directly analogous to climbing flight; this assumption starts to become questionable at steep climb angles since the quantity of aerodynamic lift provided by the wings in unaccelerated flight varies as the cosine of the climb angle with engine thrust taking up the slack.

This implies an alpha reduction for steep climb angles which in turn will have an impact upon drag and thus the sustained rate of climb.

For example, taking the 10,000 ft case

IAS ~176 mph. TAS = 205 mph
ROC = 2900 fpm ~ 33 mph

Now we can perform some trig:

Angle of climb = sin^-1(33/205) ~ 9.3º

That's reasonably steep.

At this angle the wings supply about 99% of the total vertical force required to balance gravity, with the remainder coming from the vertical component of engine thrust.

If at 1725 bhp per engine a climb rate of 4200 fpm was available at the same TAS (as suggested by the chart) the angle of climb would be ~13.5º.

At this climb angle, the wings only supply about 97% of the total vertical force*, with the remainder being supplied by the vertical component of the engine thrust.

The point is that even a small induced drag reduction will result in increased climb rate. If speed is held constant this implies a further increase in angle of climb with a resultant further reduction in induced drag.

This may produce errors in your method of ~ 5% for steep angles of climb, especially at lower IAS when induced drag increases more rapidly than lift as alpha is increased.

* Fraction of total lift supplied by wing = cos(arcsin(TAS/ROC))

OldMan____
01-13-2006, 03:48 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Ratsack:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by bolillo_loco:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Tachyon1000:
I used the 75% fuel load as that is the one suggested by TAGERT himself as valid for such testing considering the amount of fuel used in warm-up and taxi.

Your other question suggests you have not understood what I have done or the procedure used. I don't feel obligated to explain it to you as the documentation is readily available. If you had read and understood it, you would not ask such a question. </div></BLOCKQUOTE>

I'm not sure why your post was so anti-social in nature and directs hostility towards me. While you may not feel obligated to explain to you, I don't feel obligated to insult you. Your post has been challenged for its validity. Your calculations neither prove or disprove anything. Any body with a basic grasp for dazzling people with mathmatical calculations that few if any understand could prove that: bumble bees cannot fly and the "magic bullet" that killed Kennedy did in fact cause 8 other entry holes. It proves little. I thought you might want to know that a gallon of gasoline weighs 6 pounds not 6-1/2 pounds.

Also the data provided by the Pilot's manual is for a Lightning at 100% fuel not 75%.

More over, with this statement, quote: "Missions were created in FMB for target test altitude. I used Crimea map, P-38J, 75% fuel, 54€ of manifold pressure, auto radiator. Basically, the procedure is to establish level flight for target altitude at the lowest power setting needed for level flight and add throttle to desired level (here 54€ MP), and maintain level flight within 300ft of target altitude." leads me to believe that you began your climbing tests while in level flight. This is not the case of the real life data collected by Lockheed, the USAAC, and other aircraft manufacturers. My question was basic and simple enough, Did you obtain your data from a level flight or did you begin from a ground start at zero air speed? Further more, 25% fuel is not used for warm up and taxi. The manual clearly states that 50 gallons should be deducted for warm up, taxi, and take off, but in no way does it amount to 25% of the internal fuel load. It also considers take off, not just warm up and taxi.

Once again, I'm not challenging your calculations, but the manner in which you obtained your in game data.

I can provide calculated data to show the P-38J and P-38L did in fact climb at 4,500 - 5,000 + feet per minute. This was all done by teams Lockheed techs, which both collectively and individually undoubtedly have a more extensive education in both aircraft and mathmatics than you do. Does this mean that the Lightning could do it? No because calculations are subject to a lot of errors and rarely reflect what the real subject could in fact do. </div></BLOCKQUOTE>

What he's not explaining is that the test method involves level flight only. There are no climbs per se.

cheers,
Ratsack </div></BLOCKQUOTE>

I think he made that very clear.

Ratsack
01-17-2006, 05:23 AM
Oh, I agree, he did. Very clear.

There's always one, though, isn't there?http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Ratsack

AKA_TAGERT
01-20-2006, 09:35 AM
I just found a big mistake in your analysis

You said..

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Tachyon1000:Interpolating from this graph, we arrive at these ROC values for the following altitudes from the Pilots Manual Data:

5,000 ft ROC = 3000 ft/min
10,000 ft ROC = 2750 ft/min
15,000 ft ROC = 2600 ft/min
20,000 ft ROC = 2400 ft/min
25,000 ft ROC = 2050 ft/min </div></BLOCKQUOTE>

Why did you interpolate (fancy way of saying look at) the ROC values from my old ROC graph instead of using the *ACTUAL* ROC values from the Pilots Manual Chart you posted? Note in the pilots manual chart is states the ROC per alt to be the following.

<pre class="ip-ubbcode-code-pre">
5,000 ft ROC = 3200 ft/min
10,000 ft ROC = 3100 ft/min
15,000 ft ROC = 2900 ft/min
20,000 ft ROC = n/a
25,000 ft ROC = 2400 ft/min
35,000 ft ROC = 1000 ft/min</pre>

Note, these *ACTUAL* values are much larger than the interpolated values you used from my old ROC graph.

Remember, I told you a long time ago that ROC chart of mine is generated from the dx/dt of the polynomial of the TTA data points, NOT from the polynomial of the ROC data points!

Thus there will be some *differences* between the two, where the one I made is more conservative than the *ACTUAL* values. I did it more as an exercise to see just how well the dx/dt of the position, i.e. the velocity match up to the velocity values.

So, what you should have done is compare your analysis results to the *ACTUAL* ROC values from the pilots manual table that you posted.

Yet, you did not?

One has to wonder why? In that it seems like the straigt forward thing to do? Unless you had a motive? Was your motive to try and discredit my analyses and the support in trying to get Oleg to fix the ROC?

But, than again, maybe you were just ignorant and didn€t realize the pilots manual had the ROC values listed? In light of your attitude, I don€t think it was the later, but, Ill give you the benefit of the doubt in light of all the other mistakes you have made that I pointed out to you over at the The Lockheed Syndicate, what is one more?

But I digress, lets take a look at your "weight adjusted" (i.e. the larger ones) ROC values from your simple equations and comp them to the *ACTUAL* ROC values from the pilots manual. The following is what you got from your simple equation aka analysis.

<pre class="ip-ubbcode-code-pre">
5,000 ft ROC = 3068.21 ft/min
10,000 ft ROC = 2900.00 ft/min
15,000 ft ROC = 2771.60 ft/min
20,000 ft ROC = 2607.19 ft/min
25,000 ft ROC = 2274.20 ft/min
35,000 ft ROC = n/a</pre>

As you can see, your analysis agrees with mine! The ROC values are LOWER than they should be, not HIGHER!

Just to add insult to injury lets see by how much, shall we?

<pre class="ip-ubbcode-code-pre">
5,000 ft delta ROC = 3200 - 3068.21 ft/min = 131.79 ft/min
10,000 ft delta ROC = 3100 - 2900.00 ft/min = 200.00 ft/min
15,000 ft delta ROC = 2900 - 2771.60 ft/min = 128.40 ft/min
20,000 ft delta ROC = n/a - 2607.19 ft/min = n/a
25,000 ft delta ROC = 2400 - 2274.20 ft/min = 125.80 ft/min
35,000 ft delta ROC = 1000 - n/a = n/a</pre>

And when you consider the fact that you only used 75% fule instead of 100% like in real life, that would have made your ROC values even lower, thus the difference even larger!

Enjoy!

PS You€re Welcome!

Tachyon1000
01-20-2006, 06:38 PM
As you have suggested elsewhere the tests were not conducted with the correct parameters. I'll repeat them when I have time with the correct test conditions. Thanks for your continuing interest in my tests and my testing technique.

Gibbage1
01-21-2006, 12:27 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Tachyon1000:
As you have suggested elsewhere the tests were not conducted with the correct parameters. I'll repeat them when I have time with the correct test conditions. Thanks for your continuing interest in my tests and my testing technique. </div></BLOCKQUOTE>

You have yet to prove you did any test. You have a track? If not, you have no proof of your numbers. You could be making this all up for all we know.

Tachyon1000
01-21-2006, 12:05 PM
That is certainly true, but since your compatriot has pointed out numerous problems with the parameters used for the testing, posting any tracks would be pretty useless. I won't be able to redo the tests until I have some time free up. Until then, there's not alot I can say about what the correct results would be for the analysis and the testing. Thanks.

Gibbage1
01-21-2006, 04:51 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Tachyon1000:
That is certainly true, but since your compatriot has pointed out numerous problems with the parameters used for the testing, posting any tracks would be pretty useless. I won't be able to redo the tests until I have some time free up. Until then, there's not alot I can say about what the correct results would be for the analysis and the testing. Thanks. </div></BLOCKQUOTE>

It seems you have plenty of time to post baseless accusations on 3 differant forums on the same topic, but not enough time to do the actual testing. Nice.

Tachyon1000
01-21-2006, 07:22 PM
Not sure what you mean by baseless or accusations? If you are taking your cue from TAGERT, then you are only getting one side of the story. I am not sure this is appropriate discussion for this forum. You can feel free to PM me if you like, or if you feel to need to denigrate me in a public forum, have at it I suppose. I couldn't care less.

Gibbage1
01-21-2006, 08:33 PM
I mean untill you provide PROOF that the P-38 "Meets or exceeds" documented climb data in IL2, its 100% baseless. You have not yet provided any proof you did any sort of climb testing at all.

I can make a thread saying the 109 whatever out-climbs its hisorical data and make up numbers, but that would be baseless till I provide a track proving it does.

Get it yet?

BSS_CUDA
01-22-2006, 08:39 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">"In reality, there exists only fact and fiction. Opinions result from
a lack of the former and a reliance on the latter." </div></BLOCKQUOTE>