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The second thing you did not take in account is inertia. The experiment was dynamic.

The correct flight experiment showing the amount of torque must be:

Set 46/2700 rate

Trim at 150 mph IAS using slip and turn indicators (both to 0)

Watch the "red square" (in game controls indicator)

The same for 130

The same for 100 or any low IAS you can maintain.

Enjoy.

 

By the way, the real plane flies cruise with the ailerons almost in neutral and requires only small right deflection as the plane gets airborne at TO speed and power.

 

Thank you for your intructions! I will test according to the chart you have provided previously, once I get home on saturday.

 

On the chart I can see 3 different colunms. According to the description, the first one is take-off configuration with flaps up (the one you marked), the second is with flaps 20, and the third column is wave-off configuration. I would like to test this as well. ( 3rd row, 3rd column, can't mark it now, im on my phone)

 

The top of the column is missing, so I will need your help here, about exact parameters, to make this valid.

I would think: gear down, flaps full, full power (61/3000) climbing at 7520 lb weight.

 

Doing this at 90Mph, according to the chart (3rd column) I will expect about 24 deg right rudder, and right aileron moving 7 degrees up.

 

Please provide more details, if possible and/or repost the full figure.

 

Thank you very much in advance!

XP-51.thumb.jpg.f80933466acd79a716b4ccdf57dd0050.jpg


Edited by HWasp
correction
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  • ED Team
Thank you for your intructions! I will test according to the chart you have provided previously, once I get home on saturday.

 

On the chart I can see 3 different colunms. According to the description, the first one is take-off configuration with flaps up (the one you marked), the second is with flaps 20, and the third column is wave-off configuration. I would like to test this as well. ( 3rd row, 3rd column, can't mark it now, im on my phone)

 

The top of the column is missing, so I will need your help here, about exact parameters, to make this valid.

I would think: gear down, flaps full, full power (61/3000) climbing at 7520 lb weight.

 

Doing this at 90Mph, according to the chart (3rd column) I will expect about 24 deg right rudder, and right aileron moving 7 degrees up.

 

Please provide more details, if possible and/or repost the full figure.

 

Thank you very much in advance!

 

You need to find the full report - it's interesting by itself - but as far as I remember, we can not use these graps as exact references due to different prop and engine but valuable parameters could be 46/2700 (regarding Allison power) or 55-61/3000, whatever. So, the graph gives zero aileron input till 120 mph and maximal input up to 4 degrees.

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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You need to find the full report - it's interesting by itself - but as far as I remember, we can not use these graps as exact references due to different prop and engine but valuable parameters could be 46/2700 (regarding Allison power) or 55-61/3000, whatever. So, the graph gives zero aileron input till 120 mph and maximal input up to 4 degrees.

 

 

Managed to find the whole document:

 

https://crgis.ndc.nasa.gov/crgis/images/a/ac/Flying_Qualities_and_Stalling_Characteristics_of_North_American_XP-51_Airplane_1943.pdf

 

And also tested the effects according to this. With flaps up and MP 46 RPM 2800, as you said, the plane behaved according to the chart, with minimal aileron input.

 

Test 2: Flaps 20 MP 46 RPM 2800

 

In this test the FM did NOT comply with the chart, as left aileron up was needed instead of the right aileron up in the graph.

 

See attached srceenshot, graph, and track. Aircraft weight was around 7600lb as requested by the document (civilian version checked). Fuel was in balance!

P-51D_F20_torque.trk

P_51D_flaps20_graph.thumb.jpg.2b54340e925e95d92a63b8b6e96b5dd3.jpg

P-51D_flaps20_torque.thumb.jpg.85ce975bb7d32ad9e55430855df8844c.jpg

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Just a layman's report. But yes, just flew her again, and when you throttle down in flight you clearly do have to compensate with the aileron / aileron trim. So I'd say torque is indeed modelled per se.

The DCS Mi-8MTV2. The best aviational BBW experience you could ever dream of.

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3. Test: Wave off configuration

 

 

MP 46 RPM 2800 Flaps full, Gear down, according to the table attached.

 

 

In this test the FM did not comply with the graph either, results are quite similiar to the previous test with left aileron up instead of right aileron up.

 

 

See attached documents and track! Fuel was balanced this time as well.

P_51D_wave_off_graph.thumb.jpg.773881415d49cad247f10bcc2e09b5a9.jpg

P_51D_wave_off_table.jpg.204ebffc1b637bb9b6426cb596ea9376.jpg

P_51D_wave_off_torque.thumb.jpg.393567682a1aaca3845310e0b21ff8f1.jpg

P-51D_waveoff_torque.trk

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Just a layman's report. But yes, just flew her again, and when you throttle down in flight you clearly do have to compensate with the aileron / aileron trim. So I'd say torque is indeed modelled per se.

 

 

I think you might have misinterpreted my post. The torque is indeed modelled, BUT it corresponds to the XP-51 graphs in the flaps up config only. In the other two config (flaps 20 climb and go-around climb) there is a left stick input needed instead of the right stick (right aileron up) suggested by the graph.

 

Here is a last screenshot with MP 61 RPM 3000, just to be sure, that more power does not solve this.

P_51D_wave_off_61_3000.thumb.jpg.00102bb85b666609981e942525369541.jpg

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No, sorry, didn't have to do with your tests at all, just thought to respond to the OP who claimed there's no torque whatsoever. Which is BS.

 

As to your tests however, please continue. Most interesting to follow ;)

The DCS Mi-8MTV2. The best aviational BBW experience you could ever dream of.

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  • ED Team
Thank you!

 

 

Unfortunetaly this is all for now, but if you have time, you are also very welcome to run the same test flights, just to make sure, that there was no gross error on my part.

 

HWasp, thank you for the observation. Actually it was my last time mistype in the code... Corrected.

But I have to say that it was ok since the release of P-51 till... at least a month ago.

closer to XP-51 regarding its mass, thus speeds and AoA.

 

It's the same now for P-51.


Edited by Yo-Yo

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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Report which is compared to DCS P-51D is from XP-51, how much will it change, if 4 "padle" blade propeller (for P-51B/C/D) is counted istead 3 blade propeller (with thin blades which used XP-51 tested in report)?

 

Just asking...

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  • ED Team
Report which is compared to DCS P-51D is from XP-51, how much will it change, if 4 "padle" blade propeller (for P-51B/C/D) is counted istead 3 blade propeller (with thin blades which used XP-51 tested in report)?

 

Just asking...

 

Nobody says that this report shows EXACT picture for 51D, but the tendencies are obvious and general for most of the single prop fighters.

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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  • ED Team
Wait, what just happened here? HWasp provided data and convinced Yo-Yo to change the P-51? I'm trying to read through all those pages of scientific conversation :D

No buzz, the point was that I did not remember this kind of behavior, so I checked and found unwanted changes.

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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HWasp, thank you for the observation. Actually it was my last time mistype in the code... Corrected.

But I have to say that it was ok since the release of P-51 till... at least a month ago.

closer to XP-51 regarding its mass, thus speeds and AoA.

 

It's the same now for P-51.

 

 

I'm glad I could help. Looking forward to the Yak-52! :)

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  • 1 month later...

Today, (after 13 pages in this thread) I learned on the internet:

 

If you pull all the legs off a bug... it can't run away. :pilotfly:

 

Also:

 

Take the DCS Mustang, lower the gear and flaps, then back it off to about 15 inches with the prop up to 3 grand... slow it down easy to about 100 mph... then SLAM in 61 inches fast. What happens?

 

Did it get exciting? :thumbup:


Edited by lobo**

Lobo's DCS A-10C Normal Checklist & Quick Reference Handbook current version 8D available here:

http://www.digitalcombatsimulator.com/en/files/172905/

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