How do you get the most speed out of a P-47

[Iceni_Queen]

Wonder, I cannot seem to get more than 250 - 300MPH out of a P-47?

I have tried messing with inlet controls, Outlet, and others, but cannot seem to get anything to work. And even on normal mode it will not go about 250 - 300

Same with the P-40 Could only get 80% power and only around 250mph

[Raven109]

Could it be prop-pitch or the turbo-charger?

 

Here's a tutorial that can explain it better than I can do it via just words:

 

 

 

Edited October 23, 2021 by Raven109

[357th_KW]

Down at low altitude, you want 100% turbo, 100% throttle, 100% mixture, 0 oil radiator, 0 outlet cowls, 50% inlet cowls.  Once you’re up to speed pulling RPM back (the value you need varies on temp/pressure but you generally want the lowest rpm that still produces peak manifold pressure) will eek out a few more mph.  You should be able to get north of 370mph on the deck - but the engine will blow very quickly like this, so use with caution.

[CUJO_1970]

Use the fake low RPM high boost engine “settings” to give much better than actual performance.

 

Of course doing this in real life is contrary to the operating instructions for that motor and would quickly damage it but it works great in the sim if you want much better performance out of the P-47 than what you would get historically.

[Strewth]

On 10/24/2021 at 7:56 AM, Iceni_Queen said:

Wonder, I cannot seem to get more than 250 - 300MPH out of a P-47?

I have tried messing with inlet controls, Outlet, and others, but cannot seem to get anything to work. And even on normal mode it will not go about 250 - 300

Same with the P-40 Could only get 80% power and only around 250mph

Sadly, as much as I love the P-47, I am personally finding it to be more of a brick than a jug.

It loses so much speed in any form of turn and has trouble reaching a decent speed in a dive.

I have even tried it at it's "intended altitudes" and found it to be close to non-responsive.

I am not after an uber aircraft, but I have all but given up on this one, as I have grown tired of flopping around like a crippled duck.

I think the "most speed" (sadly) is as you walk away from it.

Cheers.

 

[BlitzPig_EL]

It can be a good ground attack aircraft, if escorted by other types that actually work as a fighter in this sim. (Mustang, Tempest, Spitfire).

[ShamrockOneFive]

On 10/23/2021 at 5:56 PM, Iceni_Queen said:

Wonder, I cannot seem to get more than 250 - 300MPH out of a P-47?

I have tried messing with inlet controls, Outlet, and others, but cannot seem to get anything to work. And even on normal mode it will not go about 250 - 300

Same with the P-40 Could only get 80% power and only around 250mph

 

Is this IAS or TAS that you're measuring? 300 mph, depending on altitude, is going to be pretty good.

 

If you're getting 250mph at high altitude that's probably close to the types stated maximum speed in the 420-30mph range depending on the IAS to TAS calculation.

[357th_KW]

A quick and dirty way to convert IAS to TAS is just add 2% for every 1000 feet of altitude.  So for instance, if you’re indicating 300mph at 25,000ft, you’re going to add 50%, so you’re really doing 450mph true.

[6./ZG26_Klaus_Mann]

@Strewth Online it's normally fighting the wrong Enemies and is hampered by the whole Engine Timer Malarkey.

Fighting non MW50 109s and 1.42ata Fw190s it is right at home and while not being brilliant as a Lone Wolf Plane, works amazingly well when coordinated.

[Pict]

12 minutes ago, 6./ZG26_Klaus_Mann said:

Fighting non MW50 109s and 1.42ata Fw190s it is right at home and while not being brilliant as a Lone Wolf Plane, works amazingly well when coordinated.

 

That sounds about right and probably why they called it Zemke's Wolf Pack, not Zemke the Lone Wolf 

[GiftZahnsSteigern]

Heard over Guard, "Drei...zwei....eins....."

[Strewth]

1 hour ago, 6./ZG26_Klaus_Mann said:

@Strewth Online it's normally fighting the wrong Enemies and is hampered by the whole Engine Timer Malarkey.

Fighting non MW50 109s and 1.42ata Fw190s it is right at home and while not being brilliant as a Lone Wolf Plane, works amazingly well when coordinated.

I do recognise that this is not a turn fighter and not suited to tangle with certain other fighters, but the loss of speed in any sort of turn is remarkable to say the least.
And as I said before, the thing doesn't even perform at high altitude, or in a dive. I have even put it into a 45deg dive from 4000m and not reached a decent speed for that angle. You have to go almost straight down vertically to get anywhere. 

Maybe I am doing something wrong??? But I do like the plane as a rule and I appreciate that this series is generally great with restricting certain aircraft from the "super" status. Even the 50cal seems to be a nice balance to me. But even though I generally like the aircraft, I find it frustrating at best to fly. I have read and watched footage (while taking propaganda into account)many instances where these aircraft performed well enough to take on what was left of the Luftwaffe without either being a super plane, nor a brick. Yes it definitely has its strengths, as do all aircraft in real life, or it would not have been put into action by the military. But sadly, when I doesn't (and not expected to do all) out turn, out climb, out dive, out run, out last, or out gun (at any altitude) pretty much any Axis aircraft, where at least one of those should be a strength in order to serve in any air force. I am not aware of any decent air force in the world with a large selection of various aircraft, selecting and putting into service an aircraft like the current model. I even fly the P-40, which was an early temperamental aircraft and have a lot better performance from it.

Just my experience and take on the subject.

Cheers.

[BlitzPig_EL]

In some ways, I'd rather fly the P0 2.   At least I can look at a pretty girl in the back while I get mauled by German fighters.

[Supercharger]

To squeeze everything out of the Jug i fly her always with 150 octane. But even with this additional boost you are running into an "simulator design flaw". The oil cooler flaps are more or less useless(without influence). That means that i have to throttle back during combat because of oil overheat and on the other hand, if it's cold enough, engine oil will freeze to almost zero degrees with flaps closed and engine running! Or you can try to warm up the engine on a winter map, that's impossible. They should fix this issue.....

[6./ZG26_Klaus_Mann]

9 hours ago, Supercharger said:

To squeeze everything out of the Jug i fly her always with 150 octane. But even with this additional boost you are running into an "simulator design flaw". The oil cooler flaps are more or less useless(without influence). That means that i have to throttle back during combat because of oil overheat and on the other hand, if it's cold enough, engine oil will freeze to almost zero degrees with flaps closed and engine running! Or you can try to warm up the engine on a winter map, that's impossible. They should fix this issue.....

The slow Warm up is true on all Planes and is a current Game Engine Limitation.
 

But also: On a Radial Engine Plane you never ever cut the Throttle fully for any extended Period of Time, especially not during a Dive. Never go below 30" in a Dive. 

The Problem isn't Oil Temps, but Cylinders Shock Cooling while the Pistons are still hot. Cylinders shrink rapidly and suddenly you Metal to Metal Contact. 

So, always keep Power on. 

If in Combat with the P-47 you go slow enough to Overheat, you already made a big mistake. Never go below 250 ever.

[[CPT]Crunch]

Find a group of A-20 pilots, fly bomb and attack runs with them, when it all goes bad they will protect you.

[CountZero]

2 minutes ago, [CPT]Crunch said:

Find a group of A-20 pilots, fly bomb and attack runs with them, when it all goes bad they will protect you.

its comical, but so true

[DSR_A-24]

Its all Republic Aviation propaganda. 

The "Fighter" is too heavy. Considerably heavier than the Tempest, Sea fury and Corsair is to a Bf-109 or Spitfire. And as many believe the weight doesn't do anything for dive performance, as this game perfectly represents. You can look up dive and zoom tests and the P-47 always falls short of P-51. Just think about it for moment. Republic Aviation was known for creating aircraft so heavy that they would require the entire runway to slow down, it just wouldn't slow down. Just general American trash. The roll rate was sluggish, never described as crisp or responsive. Just look at the infamous NACA's roll rate, as all aircraft reach their maximum rate of roll instantaneously, expect the P-47, because HEAVY. Pilots never dived in the P-47 as it would reach its critical Mach of 0.71. If you lost your wingman and you had a couple of Jerries on ya, you didn't dive to the channel. You died, end of story. That's why all the P-47 "Aces" didn't make it home. Here is Gunther Rall, stating to escape from a P-47, you'd just dive as the Bf-109's superior aerodynamics would grant it superior zoom and dive as perfectly represented in this simulator. NACA's test indicating the P-47D-30 critical mach as 0.86, is just more Republic Aviation lobbying. So goes for the 56FG, anything they have to say is just not true. Don't zoom or dive, just drop your flaps and hope for a long range Spitfire or Tempest to show up and save the day.

 

[Toots_LeGuerre]

I don't get what the beef is about the P-47.

Admittedly, while easy to fly it is complex to manage.

But it will outdive any plane I've found in the IL2 BOX stable.

(See pic at around 540 mph and I've seen it bumping 600 mph.)

It is a high altitude interceptor and does not do well in low altitude WW1 turning fights.

If that is your thing, get a SPAD.

 

Take about 60% fuel, make sure the turbo is connected, set the turbo outlet doors at 50% or over 400 mph the plane will start shaking badly.

Only open the gills in long hard climbs, otherwise close them.

And NEVER reduce throttle to glide down, the engine will freeze up.

For a test, go to 30,000 feet, keep the throttle forward, push the nose down.

At a certain speed, well over 400 mph, the elevators will lock up and you will lawn dart.

Gently keep testing the amount of pull back back on the stick, monitoring the airspeed.

Do it right and you'll be knocking on the door at 600 mph.

If the speed isn't high enough, steepen the dive.

Do it a number of times, until you get the hang of it.

 

It's a great plane, my favorite of the American planes.

[Raven109]

38 minutes ago, Mtnbiker1998 said:

LOL. Literally the funniest thing I've read on these forums. So now not only are all the stories of American aces "AnEcDoTaL" and not to be trusted, but even the real data is fake propaganda. LMFAO. Thats fucking rich. Go to bed Wheraboo, you're drunk. Let the adults speak.

 

Can't even tell if you're being sarcastic or not, thats how bad this forum can be about spewing garbage like that.

 

You haven't watched his link to Rall's interview, have you.... You'd immediately figure out he's being sarcastic....

 

Wonder if Rall was flying a G6 that day.

 

LE: Seems it was a G6/AS.

LE2: Other sources say that it was a Bf 109 G-5 "Schwarz ((+", W.Nr.110 089.

Edited October 28, 2021 by Raven109

[Gambit21]

3 hours ago, Mtnbiker1998 said:

LOL. Literally the funniest thing I've read on these forums. So now not only are all the stories of American aces "AnEcDoTaL" and not to be trusted, but even the real data is fake propaganda. LMFAO. Thats fucking rich. Go to bed Wheraboo, you're drunk. Let the adults speak.

 

Can't even tell if you're being sarcastic or not, thats how bad this forum can be about spewing garbage like that.

 

He's either galactically ignorant or a gigantic troll...in either case suitable for the ignore function.

 

 

[DSR_A-24]

9 hours ago, Gambit21 said:

 

He's either galactically ignorant or a gigantic troll...in either case suitable for the ignore function.

 

 

I'm sure you have much to ignore, because what I've complied is not out of the ordinary.

[chris455]

"to escape from a P-47, you'd just dive as the Bf-109's superior aerodynamics would grant it superior zoom and dive as perfectly represented in this simulator. "

I remember back in my original IL2 days, a certain person disseminating this same argument on the forums. 

He was considered a prolific liar and was said to have even doctored some original documents. Some may remember him......................I won't mention his name here.

I was told he received a lifetime ban from Wikipedia. Don't know if this was true or not. Clearly his spirit lives on.........................

P.S. Herr Rall lost his thumb to a P-47. Couldn't have been all that bad- ?

 

 

Edited November 2, 2021 by chris455

[Irishratticus72]

Strap it to a K4. 

[Kott451]

I've been flying the P40 quite a bit lately and I can't really understand the issue with the throttle.  Are you using simple engine management? or are you setting your RPMs and the manifold pressure?  I just flew the Moscow map about 1500 ft. at continuous settings - 2600 RPM and 37.2 inHg and made about 290 Mph.  Particularly for the P40 with a low critical altitude the techtips percentage of throttle is almost meaningless.   At some altitudes 80% would be combat power and at medium altitude it likely won't get you your full 37.2 inHg.  If you make 290 flying at that 1500 ft. it's likely an indicated airspeed issue as suggested by Shamrock.

 

The only other settings that could change your speed here are your mixture which should be in auto-rich (unless you take less fuel (which I recommend) and need to save auto-rich for combat) and then your engine cowl setting (because of the P40 is an adapted radial engine airframe it uses engine cowl flaps like radial engine instead of water and oil radiator covers).  But the cowl flaps fully open shouldn't cost you 40 Mph. 

[Venturi]

On 11/1/2021 at 6:44 PM, chris455 said:

"to escape from a P-47, you'd just dive as the Bf-109's superior aerodynamics would grant it superior zoom and dive as perfectly represented in this simulator. "

I remember back in my original IL2 days, a certain person disseminating this same argument on the forums. 

He was considered a prolific liar and was said to have even doctored some original documents. Some may remember him......................I won't mention his name here.

 

 

 

the C who shall not be named

[453=SGII_Wotan]

Well being a Dora fanatic of Il21946 I would dive, I found P-47s to be a nightmare boom and zoomer especially with 8 50cal machine guns and fight really high 7000k plus

don't go below that and don't let your speed fall below 400kph

 

[Knarley-Bob]

Get as high as you can, then straight down, throttle wide open. Just before you hit the deck you'll be there.

Bought BoBP so I could fly the P-47. What a disapointment. If the the planes in Normandy are modeled the same, I'm not getting that one for sure. In My Humble Opinion, that is.

[Knarley-Bob]

On 10/24/2021 at 10:55 AM, CUJO_1970 said:

Use the fake low RPM high boost engine “settings” to give much better than actual performance.

 

Of course doing this in real life is contrary to the operating instructions for that motor and would quickly damage it but it works great in the sim if you want much better performance out of the P-47 than what you would get historically.

Hit the 'BOOST' button this afternoon, CST, it doesn't even make the engine sound different. I at least made it do that before..........

[sgt-pepper]

I found the P-47 to be quite underwhelming in IL2, while in reality it was not. Maybe it's due to a bad implementation, maybe it's just me - but it's good to know that I'm not the only one to struggle here...

 

On 10/24/2021 at 2:38 AM, VBF-12_KW said:

Down at low altitude, you want 100% turbo, 100% throttle, 100% mixture, 0 oil radiator, 0 outlet cowls, 50% inlet cowls.  

Well, I'd like to contest that. I have no idea whether this works in the sim or not, but if it works, the the engine modelling is all wrong:

The turbocharger is used to force air into the engine manifold. This becomes more important the higher you go, because of the decreasing air density. The turbocharger has a downside however: It is using the exhaust gas pressure to power itself, and therefore takes a direct hit on the engine performance.

 

The use of the turbocharger REDUCES engine performance by approximately 300 hp. In turn it gives the engine air to breathe at high altitudes.

 

In reality, the P-47 would not use the turbo at low altitudes, so the answer would be 0% turbo, 100% throttle. I'll have to do some testing in the sim to check how it is implemented....

 

On 10/24/2021 at 5:55 PM, CUJO_1970 said:

Use the fake low RPM high boost engine “settings” to give much better than actual performance.

 

could you elaborate on that? what is the fake boost setting?

[BladeMeister]

9 hours ago, sgt-pepper said:

The use of the turbocharger REDUCES engine performance by approximately 300 hp. In turn it gives the engine air to breathe at high altitudes.

 

 

Please explain this and link some factual evidence supporting this statement. Maybe it is just me, but as an ex professional automotive machinist this statement makes no sense to me. Please elaborate.

 

S!Blade<><

[BlitzPig_EL]

A mechanically driven supercharger, like the Merlin or DB605 used, definitely saps power from an engine, an exhaust gas driven turbosupercharger is far more efficient, and doesn't mechanically tap power off the crankshaft of an engine.

[BladeMeister]

1 hour ago, BlitzPig_EL said:

A mechanically driven supercharger, like the Merlin or DB605 used, definitely saps power from an engine, an exhaust gas driven turbosupercharger is far more efficient, and doesn't mechanically tap power off the crankshaft of an engine.

Ok, but even in the pure supercharged engines the amount of horsepower consumed by the supcharger's gear or belt drive coming from the crankshaft is offset and handedly exceeded by the amount of extra horsepower generated by the higher cylinder air charge and resulting higher compression per cylinder. In the same way the turbo supercharged engine generates much more increased horsepower than induced horsepower loss. Otherwise their would be no point in adding these upgrades because in essence they would be downgrades. There cannot be 300 HP loss induced by the turbo supercharger in a P47. That makes no sense.

 

SBlade<><

[LukeFF]

I know one of the P-47 manuals talks about this phenomenon. I'll see if I can find the relevant text and post it here. 

[Raven109]

The reason for wasting power is because the air is compressed twice to reach the same MP. The P-47 has both a supercharger and a turbocharger.

 

If I recall correctly only the manual for the P-47N states this:

 

 

Basically you're "wasting" (as in throwing away) )the HP that your engine is using to spin the supercharger impeller, by boosting your engine using your turbo, when the supercharger boost is enough. Not to mention the losses due to back-pressure, which come with the use of a turbocharger, especially when you don't need it and the heat that is created by compressing the air when you don't need to.

 

Here's Greg talking about it (min 5:23):

 

 

A diagram which shows the supercharger (diagram component 3. Internal blower) and the turbo-supercharger (diagram component 13. Turbo compressor). So stage 1 and stage 2 boosting? Same concept on some of the bombers (B-17/24, if I recall correctly)

 

Edited November 11, 2021 by Raven109

[LukeFF]

Thanks, that was the section I was thinking about. ??

[sgt-pepper]

5 hours ago, BladeMeister said:

Please explain this and link some factual evidence supporting this statement. Maybe it is just me, but as an ex professional automotive machinist this statement makes no sense to me. Please elaborate.

 

S!Blade<><

I agree it sounds strange at the first moment. But thankfully Raven has linked all the required material. Gregs videos are a great source on it. 

 

To me it sounds logical, I imagine it works like this:

 

• Basically the geared supercharger is delivering enough air to the engine at low altitudes. There is just no need for more air, because its already at a point where it is maxed out.
   
• This changes at higher altitudes, when the air pressure goes down. At a certain point the engine is starving for additional air, and then it makes sense to add the exhaust driven turbo charger to the mix to deliver additional air to the engine.
   
• Of course the super charger also needs energy to run. This is taken from the exhaust. Because the exhaust gases can no longer freely escape from the engine, the expanding gases in the cylinder now need to push against the back pressure of the turbocharger. This energy is taken from the piston which is now working hard to push the exhaust out of the cylinder. This causes the engine tlose some hp  with the turbocharger fully enganged...

 

I think I got the 300hp wrong. These may be consumed by the geared supercharger !? Have to watch the video again...

 

Edited November 11, 2021 by sgt-pepper

[Knarley-Bob]

So what of the water injection? Is that also called 'Boost'? I tried it the other day and nada. Or is that key also to the 'chargers"?

[BladeMeister]

So, I am assuming the back pressure on the exhaust is what causes the parasitic HP consumption because the Supercharger is engaged to the Turbocharger directly through gears on their main shafts and has no physical connection with the Double Wasp engine. I am also assuming that under 7000 feet, by not engaging the turbo lever, that the exhaust wastegate would be open and relieve most of the exhaust back pressure? So at under 7000 feet this is not really robbing the engine of 300 horsepower, but it is simply not producing the top HP output that it is capable of at over 7000 feet. And at higher altitudes by closing the waste gate mostly, spinning the turbo to max rpm and driving the supercharger to it max efficiency and compressing the thinner air and increasing the volume of the air charge to each cylinder, thereby increasing the compression ratio, each cylinder can produce the higher HP output. So, fly high and you are possibly deadly as a fighter, but fly low and your slow and possibly no more that a target?

 

So, if MP is as it always seems to be, low altitude DFing, then the P47 is only useful at ground pounding objectives if it has a fighter escort, since almost no one organizes high altitude bombing in MP. Does that sound about right?

 

S!Blade<><

[Raven109]

The issue described by the manual is about the way the pilot manages the throttle and turbo levers, in the context of linking them together. The manual actually states that it's fine to couple them at all alts if the pilot really needs to (e.g. easier engine management during combat/faster engine response). 

 

 

 

The issue is in situations where the compressor can already supply the MP values required by the pilot. In this case it's recommended not to link the levers, due to inefficient use of the entire power system.

 

When the pilot does need the extra MP above what the compressor can provide, then it's ok to use the turbo, and if he's not in a pickle he should advance the throttle first, i.e rely on the compressor to provide the MP it can, and then the turbo lever if more MP is needed.

 

When the pilot needs a quick response from the entire system, then it's fine to operate the system in an inefficient way, because pushing the throttle forward and only afterwards the turbo lever takes longer than when they are linked together.

 

The supercharger and the turbo are not physically connected. In fact they are separated by meters of ducts, the compressor being attached to the engine, while the turbo being way back in the tail. In-between the two there's the butterfly throttle and the carburetor. By compressor I'm not referring to the cold part of the turbocharger. There is actually a separate supercharger (a separate impeller) driven by the engine crankshaft, which is right next to the engine.

 

If the pilot needs an MP value which can be supplied by the compressor without opening fully the throttle, using the two levers while linked, means that the compressed air from the turbo is pushing against the throttle plate, without any purpose.

 

The following diagram can probably help a bit. Where it says "Supercharger" and "Turbine" back in the tail, that is actually what we call turbo (turbocharger, turbo-supercharger). Where it says "To the carburator" close to the nose, that's where the additional supercharger impeller is. The other diagram I posted shows the concept better.

 

I would think of it in terms of inefficient use of the entire power system, rather than "wasting <<up to>> 300 hp"

Edited November 12, 2021 by Raven109