P-40 Engine - Greg's Airplanes on Youtube

[NO.20_Krispy_Duck]

 

[354thFG_Drewm3i-VR]

Thanks for posting this. I saw it last night and thought about posting it here. I think this information and documentation should be used to fix our absurd engine limits.

[I./JG52_Woutwocampe]

Easily one of the best channel on yt. He knows the score. 

[BMA_FlyingShark]

10 minutes ago, I./JG52_Woutwocampe said:

Easily one of the best channel on yt. He knows the score. 

Indeed, very interesting channel.

 

Have a nice day.

 

And before I forget, from me too, thanks for posting.

 

Have a nice day.

 

[Gambit21]

18:25 onwards is just gold, and what many of us have been saying for years.

 

The manual has little to do with what pilots were actually doing operationaly, and yes bringing the aircraft home.

 

 

[56RAF_phoenix56]

44 minutes ago, Gambit21 said:

The manual has little to do with what pilots were actually doing operationaly, and yes bringing the aircraft home.

 

 

I'm afraid that's true for all aircraft. If your life depended on it, you'd fly beyond the limits.

The trouble is, there's little real data for all the aircraft, plus we get a shiny new one each time we spawn.

I'd love if if we could have a dedicated personal 'plane that retained the wear and potential damage from previous flights. It's not impossible.

 

56RAF_phoenix

[354thFG_Drewm3i-VR]

The only caveat to the Allison 1710-39/69 being able to run around 70" at 3000 rpms for 5-15 minutes at a time is that it did so with 130 octane fuel, according to a comment from Greg below his video on the p-40 engine. We should have the option to run the p-40 on 130 octane fuel, allowing much higher boost than the current 100 octane. We should at least be able to run combat power continuously and WEP for a reliable 5-15 minutes as that is what was widely reported in the field for the Allison, which is arguably the toughest in-line v-12 of the war.

Edited November 30, 2021 by -332FG-drewm3i-VR

[Ace_Pilto]

When I hear "Greetings, this is Greg" at the beginning of a video, I start paying more attention than usual. (I wish he'd do more car stuff too)

[Motherbrain]

His channel is super hard-core. Even I blank out sometimes. ?

 

But I love his content. It's probably the best aviation nerd channel on YT.

 

Edited November 30, 2021 by Motherbrain

[Alexmarine]

29 minutes ago, -332FG-drewm3i-VR said:

The only caveat to the Allison 1710-39/69 being able to run around 70" at 3000 rpms for 5-15 minutes at a time is that it did so with 130 octane fuel, according to a comment from Greg below his video on the p-40 engine. We should have the option to run the p-40 on 130 octane fuel, allowing much higher boost than the current 100 octane. We should at least be able to run combat power continuously and WEP for a reliable 5-15 minutes as that is what was widely reported in the field for the Allison, which is arguably the toughest in-line v-12 of the war.

 

Or just do as the Soviets did: fly them with fuel that barely went up to 100 octanes and disregard whatever some of those Yankee boys wrote in those silly manuals 

[Gambit21]

The Allison allowed “Fly it like you stole it” be sure.

[Ace_Pilto]

It should, they still use them today in tractor pulls. They're tough, not airy fairy engines.

[CountZero]

There is an option in realisam settings caled undestructable, when turned on engine timers have no effect, its great for SP, only problem is airplanes dont get damaged on colisions/crashes. So its posible to just make engine timers optional, just separate it from this undestructable option and fuel and overheating will fix all the problems, no need for some complex time consuming revisions, just make it on/off option. They will never fined time to overhaul engine damage system on all airplanes. Simple and fast, just add on/off option, and it covers all airplanes at once.

 

From last part of video it looks like greg is also turning to dcs insted box.

Edited November 30, 2021 by CountZero

[Gambit21]

41 minutes ago, Ace_Pilto said:

It should, they still use them today in tractor pulls. They're tough, not airy fairy engines.

 

Yep

[Cpt_Siddy]

Imagine how poorly would have soviets thing go with p-40 and p-39's if they knew how to read English manuals. 

[NO.20_Krispy_Duck]

Greg's channel is outstanding. He really digs into the data. It's worth subscribing if you're deeply into the period aircraft. I wish the P-40 engine would be revisited with Greg's data and discussion.

[Cpt_Siddy]

Remember, that allot of this manifold stuff is also temperature dependent. 

 

When it is balmy -20C  Russian winter outside, the charge temps don't rise nearly as high as when it is +30C in shade. 

This is totally not modeled in the game in any way, while in real life this is very big factor for knock conditions for your engine. 

[354thFG_Drewm3i-VR]

11 minutes ago, Cpt_Siddy said:

Remember, that allot of this manifold stuff is also temperature dependent. 

 

When it is balmy -20C  Russian winter outside, the charge temps don't rise nearly as high as when it is +30C in shade. 

This is totally not modeled in the game in any way, while in real life this is very big factor for knock conditions for your engine. 

Perhaps so, but the British in North Africa (as well as the Australians in the South Pacific) were the ones running over 70" routinely, not the Russians. Because of the huge frontal area, the p-40 had very good cooling overall compared to sleeker designs.

Edited December 1, 2021 by -332FG-drewm3i-VR

[Cpt_Siddy]

39 minutes ago, -332FG-drewm3i-VR said:

Perhaps so, but the British in North Africa (as well as the Australians in the South Pacific) were the ones running over 70" routinely, not the Russians. Because of the huge frontal area, the p-40 had very good cooling overall compared to sleeker designs.

Its not about the cooling per se, but the charge air temperature during the compression. 

When you compress the air in cylinder, the end temperature, assuming simplified adiabatic conditions, rises substantially. The initial temperature conditions effect the end result considerably. 

 

If you are having compression ration 1:7, the end temperatures are roughly as follows: -20C --> 460C, and +20C --> 610C 

This is considerable contribution to knock conditions. you get 150C swing in end conditions from 40C difference in initial delta. 

Ofc real engines are not as simple as this back of the napkin example, but it serves to illustrate that environment play a big role in how much power you can extract from your engine, all else being equal. 

 

Edited December 1, 2021 by Cpt_Siddy

[the_emperor]

To be fair, the soviet manual also limits the P-40 to 5 minutes of 3000rpm at 42 inches (1070 mm) Hg.

But yes, it seems that the P-40 and its Allison Engine should be able to withand a bit more abuse, than it is currently in the game.

[I./JG52_Woutwocampe]

16 hours ago, Cpt_Siddy said:

Remember, that allot of this manifold stuff is also temperature dependent. 

 

When it is balmy -20C  Russian winter outside, the charge temps don't rise nearly as high as when it is +30C in shade. 

This is totally not modeled in the game in any way, while in real life this is very big factor for knock conditions for your engine. 

 

Temperature in GB clearly has an impact on engine management. The way you'll handle radiators and cowl shutters depends on the temperature and its very noticeable when you go from winter to summer. 

 

Edit : about MP though, I dont know if atm pressure and temp has an impact on detonation thresholds. 

 

Edited December 1, 2021 by I./JG52_Woutwocampe

[TRRA15]

On 11/30/2021 at 9:09 PM, NO.20_Krispy_Duck said:

Greg's channel is outstanding. He really digs into the data. It's worth subscribing if you're deeply into the period aircraft. I wish the P-40 engine would be revisited with Greg's data and discussion.

It really is. It seems as though he nearly literally takes pains to scour to locate and then and collate data and references to be as accurate as possible. A night and day difference to the banal and superficial tripe on TV shows like 'Dogfights' and 'Air Warriors' and the like.

[[F.Circus]FrangibleCover]

Something that might be worth considering is adding a tickbox option for the P-40E for 'relaxed engine limitations' based on the vast body of anecdotal evidence of V-1710s being pushed beyond their stated limits and surviving without issues. If you think that's how the P-40E should be, tick the box or enable it on your server. If you don't think that's fair, disable it. Exactly the same as the 262's engine flow limiters.

[the_emperor]

I am no expert in that regard, but shouldnt the boost limit for the P-40E also be restricted by the available Fuel? E.g. the russian Avgas has 95octan IIRC.

and it limits the Yaks-Klimov engine with a crompression ration of 7.1:1 to 1050mm Hg boost.

and the P40E with a CR of 6.65:1 to 1070mm Hg boost.

 

Maybe it would make the P-40 more flyable if we put the time limit not on the Boost directly but on the engine temperatures (while higher boost increases temperatures more rapidly) just like in the Yak fighters.

Fortunately the soviet manuals give us those for both Yak and P-40E:

Yak:  Water 110°C , Oil 115°C for 5 Minutes and 110°C for 10 minutes.

P40: 125°C Glycol for 5 Minutes, oil (summer) 85° for 5 minutes, oil (winter) 80°C for 5 minutes)

Edited December 4, 2021 by the_emperor

[4thFG_Cap_D_Gentile]

2 hours ago, the_emperor said:

I am no expert in that regard, but shouldnt the boost limit for the P-40E also be restricted by the available Fuel? E.g. the russian Avgas has 95octan IIRC.

and it limits the Yaks-Klimov engine with a crompression ration of 7.1:1 to 1050mm Hg boost.

and the P40E with a CR of 6.65:1 to 1070mm Hg boost.

 

Maybe it would make the P-40 more flyable if we put the time limit not on the Boost directly but on the engine temperatures (while higher boost increases temperatures more rapidly) just like in the Yak fighters.

Fortunately the soviet manuals give us those for both Yak and P-40E:

Yak:  Water 110°C , Oil 115°C for 5 Minutes and 110°C for 10 minutes.

P40: 125°C Glycol for 5 Minutes, oil (summer) 85° for 5 minutes, oil (winter) 80°C for 5 minutes)

And on the same airfield there are Spitfires and Hurricanes that can pull full MP from the same fuel bowsers? The 40 is so much out of line as is the 39. It has amazed me for years now what the developers missed about the Allison 1710, Klimov propoganda?

 

Cheers

[the_emperor]

2 hours ago, Ojisan_Mjoelner said:

And on the same airfield there are Spitfires and Hurricanes that can pull full MP from the same fuel bowsers?

That is indeed a very interesting point.

I just argued from the soviet perspectiv and the avaible avgas and the manuals I have at hand. I personaly would love to see a little bit more abusable P-40, since it seems more fitting to the field reports.

[Dennis_Nedry]

On 12/3/2021 at 6:01 PM, [F.Circus]FrangibleCover said:

Something that might be worth considering is adding a tickbox option for the P-40E for 'relaxed engine limitations' based on the vast body of anecdotal evidence of V-1710s being pushed beyond their stated limits and surviving without issues. If you think that's how the P-40E should be, tick the box or enable it on your server. If you don't think that's fair, disable it. Exactly the same as the 262's engine flow limiters.

Great idea.  Also, maybe a persistent engine timer?  So the engines rated settings would still apply as normal but say you have already run 60 inHg for 15min.  Now the engine may blow up at any moment.

[gimpy117]

13 hours ago, Ojisan_Mjoelner said:

And on the same airfield there are Spitfires and Hurricanes that can pull full MP from the same fuel bowsers? The 40 is so much out of line as is the 39. It has amazed me for years now what the developers missed about the Allison 1710, Klimov propoganda?

 

Cheers

woah, yeah I never thought about that either. really I think it's an artifact of the P-40 being the first "allied" plane to hit the scene. I'm assuming the Spits and Canes are running as if they were on 130? 

[Bert_Foster]

Perhaps a 100 Octane mod option with more liberal Engine limits ?

[354thFG_Drewm3i-VR]

9 hours ago, Bert_Foster said:

Perhaps a 100 Octane mod option with more liberal Engine limits ?

The in game p40 is running on 100 octane.