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Legioneod

P-47 Flight Model Discussion

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Interestingly the Brits found no limiting airspeed for the Thunderbolt. Even the Tempest is listed as 550.

 

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They didn't list it in that table, as with several others. Manuals give limiting speeds as low as 250mph indicated at 35+k feet. Basically it's 500 up to 10k and then -50 for every 5000 feet.

 

An early report says 520 indicated up to 10k, and NACA says they tested a configuration at 600mph true air speed in flight (that would roughly be 500 indicated at 10k).

 

They don't lose ailerons, though, they just get a nose down attitude, which makes dives hard to recover until you reach lower altitudes (and apply power). Mach drag raise starts at figures of about 0.7 already, so you can't really expect to exceed 0.8 by much. Which again is roughly 600 true at sea level, less as you go up. I've read about 0.78 in flight tests at the most, though reaching maximum Mach was not the point of these tests.

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Posted (edited)
4 hours ago, Talon_ said:

image.thumb.png.eeb299a20995aa254493f93d82ff73b0.png

 

Interestingly the Brits found no limiting airspeed for the Thunderbolt. Even the Tempest is listed as 550.

 

 

Interesting to note that the Brits had a higher limiting speed for the Thunderbolt than the Americans. 520 iirc vs 500 mph

 

2 hours ago, JtD said:

They didn't list it in that table, as with several others. Manuals give limiting speeds as low as 250mph indicated at 35+k feet. Basically it's 500 up to 10k and then -50 for every 5000 feet.

 

An early report says 520 indicated up to 10k, and NACA says they tested a configuration at 600mph true air speed in flight (that would roughly be 500 indicated at 10k).

 

They don't lose ailerons, though, they just get a nose down attitude, which makes dives hard to recover until you reach lower altitudes (and apply power). Mach drag raise starts at figures of about 0.7 already, so you can't really expect to exceed 0.8 by much. Which again is roughly 600 true at sea level, less as you go up. I've read about 0.78 in flight tests at the most, though reaching maximum Mach was not the point of these tests.

 

Exactly this. They don't lose surfaces in a dive irl. The limiting factor on P-47 dive limit was compressability and control in a dive. Structurally the P-47 could hit it's maximum mach (0.83) and be fine. I wouldn't expect to reach these speeds much though, the chances of surviving them are low due to compressability.

Edited by Legioneod

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46 minutes ago, Legioneod said:

Interesting to note that the Brits had a higher limiting speed for the Thunderbolt than the Americans. 520 iirc vs 500 mph

 

Could be the British had razor-backs and Americans tested the newer bubble-canopy models? Or they had different standards measuring this?

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The 520 is a US figure which the British used. It's not that every US manual says exactly the same.

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Posted (edited)
51 minutes ago, Ehret said:

 

Could be the British had razor-backs and Americans tested the newer bubble-canopy models? Or they had different standards measuring this?

Brits just had a higher allowed speed listed. Americans used a larger safety margin.

 

29 minutes ago, JtD said:

The 520 is a US figure which the British used. It's not that every US manual says exactly the same.

Nearly all American manuals list the safe dive limit of the P-47 as 500 mph IAS the only exception is later P-47s like the N with a safety limit of 560 mph IAS.

 

 

EDIT:

Was reading through some documents and it states synchronized guns weren't provided on the P-47 (at least that's the way I read it.)

Based on this I think synchronization should be removed for the P-47 and replaced with a more accurate ballistic model.

 

234144533_sunchroguns.PNG.49af238f5ebad7840862450d466494b4.PNG

Edited by Legioneod
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37 minutes ago, Legioneod said:

Was reading through some documents and it states synchronized guns weren't provided on the P-47 (at least that's the way I read it.)

Based on this I think synchronization should be removed for the P-47 and replaced with a more accurate ballistic model.

 

Some time ago I posted a video showing P-51D firing her guns on the ground where the free-firing was apparent.

There is no point of any synchronization for wing batteries of 0.50" caliber guns at all if the bullets don't pass through a propeller disc. Just none.

The only possible justification could be the game has an optimization of some kind which doesn't compute every round path individually but do the whole volley as something like a converging line. If that's the case then... well.

(it could explain few things but I hope that's not the case)

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10 minutes ago, Ehret said:

The only possible justification could be the game has an optimization of some kind which doesn't compute every round path individually but do the whole volley as something like a converging line. If that's the case then... well.

(it could explain few things but I hope that's not the case)

 

It's actually super simple - the game fires a gun when the gun switch is pushed. There's simply no delay simulated from gun to gun.

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5 minutes ago, Talon_ said:

It's actually super simple - the game fires a gun when the gun switch is pushed. There's simply no delay simulated from gun to gun.

 

Then where is the problem to implemented it..! The program must keep cycling rate variables already; just set them with some spread the way the left and right sides have the same cumulative rate. Shouldn't be too hard to do... actually should be very simple comparing to all other stuff (like 3d graphics) the game has to compute.

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Actually all guns have a delay. In case of WW2 guns, it's set to 1 ms ingame (it's 2 ms for the WW1 guns of FC). So it's easily possible to create a desynchronized behaviour by copying the guns and changing the delay for each gun. Then editing the plane files to use those different guns. Takes less than 5 minutes.

 

I suggested it a few years ago for the P-40.

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3 minutes ago, Matt said:

Actually all guns have a delay. In case of WW2 guns, it's set to 1 ms ingame (it's 2 ms for the WW1 guns of FC). So it's easily possible to create a desynchronized behaviour by copying the guns and changing the delay for each gun. Then editing the plane files to use those different guns. Takes less than 5 minutes.

 

I suggested it a few years ago for the P-40.

Need's to happen. Especially since the P-47 (or most American aircraft iirc) didn't have synchronized .50s.

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3 minutes ago, Legioneod said:

Need's to happen. Especially since the P-47 (or most American aircraft iirc) didn't have synchronized .50s.

 

All 3 US planes in the BOBP should have free-firing guns. I'm not completely certain about the Spitfire and the Tempest but I'd bet that they have free firing guns, too.

11 minutes ago, Matt said:

Actually all guns have a delay. In case of WW2 guns, it's set to 1 ms ingame (it's 2 ms for the WW1 guns of FC). So it's easily possible to create a desynchronized behaviour by copying the guns and changing the delay for each gun. Then editing the plane files to use those different guns. Takes less than 5 minutes.

 

I suggested it a few years ago for the P-40.

 

Well... that's both interesting and (very) bad to hear. :(

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Another way to unsychronize would be to give each (or each pair) of guns different rates of fire, after all the variability of the AN/M2 was 750-850 rpm

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1 minute ago, =362nd_FS=RoflSeal said:

Another way to unsychronize would be to give each (or each pair) of guns different rates of fire, after all the variability of the AN/M2 was 750-850 rpm

Could work and be an easier way to model desync.

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That would be just as easy. Same method really, because by changing the firing delay and without changing the rechamber time, the rate of fire would automatically change as a result. But then you would always have the same guns/pairs running out of ammo sooner/later than the rest. Not a big issue, but probably not necessary.

 

As for the maximum dive speed which has been mentioned above, since the official speed limit is around 600 mph TAS and taking into account that most (maybe all?) planes in BoX are modelled with a maximum dive speed above the official dive speed limit (some up to 100 kph  or more above official limit), there really shouldn't be anything falling off the P-47 in a dive.

 

I was happy to see that the Me 262 doesn't have any such thing as ailerons falling off when exceeding dive speed and i hope that kind of modelling gets carried over to the P-47 and other planes in the future.

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4 hours ago, Matt said:

That would be just as easy. Same method really, because by changing the firing delay and without changing the rechamber time, the rate of fire would automatically change as a result. But then you would always have the same guns/pairs running out of ammo sooner/later than the rest. Not a big issue, but probably not necessary.

 

As for the maximum dive speed which has been mentioned above, since the official speed limit is around 600 mph TAS and taking into account that most (maybe all?) planes in BoX are modelled with a maximum dive speed above the official dive speed limit (some up to 100 kph  or more above official limit), there really shouldn't be anything falling off the P-47 in a dive.

 

I was happy to see that the Me 262 doesn't have any such thing as ailerons falling off when exceeding dive speed and i hope that kind of modelling gets carried over to the P-47 and other planes in the future.

I wonder if they can make it cycle with each pull of the trigger? That way you wouldn't get the same exact rate of fire per pair each time, it would be more random. This way you don't have the same pairs running out of ammo earlier/later each time.

 

Another way they could do it is have the guns fire at the same time with the first pull of the trigger then have them desync as the trigger is held, this would happen within a few rounds being fired. It's not much different from the above method, a bit more realistic though I think.

 

As far as the dive limit I really hope it gets updated in the future for all aircraft. Not every aircraft should lose parts and not every aircraft should be able to dive to the max without losing parts, it'd should be a characteristic of each individual aircraft model.

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