P-40 Engine Settings as I found them (a bit weird)

[Venturi]

"Figure 86, auto,attic manifold pressure regulator installed"

 

Hm, wonder if this optional piece of equipment was installed on the P40e?.

[=362nd_FS=RoflSeal]

Nice Picture except P-40E's F3R didn't have an automatic manifold pressure regulator installed

 

https://books.google.co.uk/books?id=tTPi07FB7esC&pg=PT295&dq=p-40+automatic+boost+control&hl=en&sa=X&ved=0ahUKEwjFgrSUl9jLAhUFRhQKHcNfAZoQ6AEILzAB#v=onepage&q=p-40%20automatic%20boost%20control&f=false

 

[NZTyphoon]

Just for interest, attached is a technical directive for adjusting the Allison's Automatic Manifold pressure Regulator, dated November 30 1942. The F3R, or V-1710-39 was equipped with the regulator (pages 1 & 3).

Allison V-1710 Adjustment of Regulator.pdf

Edited March 24, 2016 by NZTyphoon

[MiloMorai]

There would be stops as the butterfly would open too far or not enough.

[=362nd_FS=RoflSeal]

Just for interest, attached is a technical directive for adjusting the Allison's Automatic Manifold pressure Regulator, dated November 30 1942. The F3R, or V-1710-39 was equipped with the regulator (pages 1 & 3).

Nice, though I knew the P-51 had throttle regulator installed in it I haven't read before P-40E installed in it, e.g. anecdote of the guy doing his training in 1944 on the P-40E specifically mentions this.I guess the P-40E was too old for it to have any priority, whilst the P-51 was still serving in Italy and CBI.

 

EDIt: Just re-read second paragraph, aircraft in non-combat zones will not have regulators installed so that clears that up.

Edited March 24, 2016 by RoflSeal

[Venturi]

Just for interest, attached is a technical directive for adjusting the Allison's Automatic Manifold pressure Regulator, dated November 30 1942. The F3R, or V-1710-39 was equipped with the regulator (pages 1 & 3).

Interesting how the first page of your article mentions automatic regulators were installed on the P51 allisons but not the P40. Same engine dash. Also the title of th document is "aircraft accessories"

 

Yeah, MM like on an old four barrel carb. But not to use it to limit how far you can open the throttle which is what he's saying.

[Crump]

 

 

Nice Picture except P-40E's F3R didn't have an automatic manifold pressure regulator installed

 

 

 

"Figure 86, auto,attic manifold pressure regulator installed" Hm, wonder if this optional piece of equipment was installed on the P40e?.

 

[Venturi]

Just for interest, attached is a technical directive for adjusting the Allison's Automatic Manifold pressure Regulator, dated November 30 1942. The F3R, or V-1710-39 was equipped with the regulator (pages 1 & 3).

 

I also particularly like the section which discusses the need to change spark plugs after "extended use of War Emergency Power" lol

 

Wonder if "extended" was 2 min or 5 min? Lol

[Crump]

You do know the picture I posted is from the Allison F3R operating and maintenance instructions.....right?

[=362nd_FS=RoflSeal]

You do know the picture I posted is from the Allison F3R operating and maintenance instructions.....right?

Yeah, its been "cleared up. "

 

P-51s regulator from the start.

P-40E, no regulator until this technical order, where only those in combat zones would recieve it, aircraft in training squadrons wouldn't.

 

I sense an unlock somewhere, afterall devs love their unlocks.

Edited March 24, 2016 by RoflSeal

[MiloMorai]

Yeah, MM like on an old four barrel carb. But not to use it to limit how far you can open the throttle which is what he's saying.

 

Yup, be sure.

[Venturi]

I still haven't gotten ANY proof that a boost regulator was installed in p40e allisons. In fact to the contrary, All I see is that p51 allisons got it from the factory, but that the instructions were for "installations in th field" for the p40

 

Why was this if these ac were still being manufactured?

 

Do you have proof these were installed on a/c in the field or is this just an "option"?

 

It especially needs to relate to the Soviet lend lease a/c

 

Also reconcile with the other anecdotes of use of high pressures in the letter

 

I think this is just an anecdotal document for "the non-budget premium version of the Allison going in the new mustang"

Edited March 24, 2016 by Venturi

[LukeFF]

I have readi it several times and have a copy of my own.  It is a letter and not a Technical Order or Operating Instructions.

 

In other words it is not a legal instrument that either a pilot or a mechanic use to determine their authorized operating limitations.  

 

Just as I thought, it is hopeless trying to have a meaningful discussion with you. It is a letter from the chief engineer from Allison detailing what the engine could actually handle. 

[Venturi]

It is fascinating to read about the British actually REMOVING said regulator on their Allison P51s (don't see a document where they did that for Tomahawks, Kityhawks, hmm) to obtain 72" of boost FOR 20 MINUTES.

[JtD]

I still haven't gotten ANY proof that a boost regulator was installed in p40e allisons.

There wasn't. It was a new feature on later P-40's, from the top of my head from P-40M onwards, with a different Allison.

 

FWIW, reading a statement along the lines that engines don't just get uprated - another engine where this happened was the M-105, from PA to PF. There's no difference between the two, except for different blinds in the induction system in order to adjust the ABC to the higher boost. The conversion instructions in the manual are limited to something like a half page paragraph describing the adjustments to the inductions system controls. The WEP cleared for 5 minutes on the PA would then become nominal, unlimited power on the PF, slightly boosted.

Several other engines had their outputs increased in a similar fashion, however, while there was no specific modification to the engine necessary, there often were some prerequisites, such as the usage of a certain kind of spark plug or the engine being from a certain sub-series.

The Allison is nothing special in that regard.

[Brano]

Just a remark to M-105PF. First tests were really done only by conversion of PA version mentioned by JtD. But for serial production,there were several changes implemented in the construction of the engine - strenghtened piston rods,enlargement of holes for suction of air in carburetor and cooling system upgrade (new radiator and other small construction changes)

[JtD]

All true, but existing PA engines could be converted in the field to PF by minor adjustments. This of course does not imply that the engine wasn't being continuously developed back in the factory just like any other engine.

 

Just for perspective, the modifications list for the Merlin XX series engines is roughly 500 pages long, containing nearly as many modifications over a time span from 1941-1945. It also had permissible boosts increased several times in several subseries', and some of the actual boost increases came without any specific engine modification. At some point it was just found that the engine in the current condition could take more than it currently did.

 

Pretty much the same with running 45' cleared Allisons at 60+', at some point they could just take it.

[Crump]

 

 

It is a letter from the chief engineer from Allison detailing what the engine could actually handle. 

 

 

Right....

 

And he knows that it is not a legal instrument by convention to change limitations.  Geez, guy...he is just letting them know that Allison understands and is doing their best to give them what they need to win the war.

 

 

It is not a document a pilot or a mechanic use to change the limitations. 

 

This is a document used to changed limitations and is dated 4 months AFTER the December 1942 memo in April 1943:

 

 

 

It represents the latest and greatest limitations the engine was authorized to use as of April 1943.

 

 

 

As for the Regulator...

 

This is also from the April 1943 Operating Instructions for the V-1710F3R engine and is clearly labeled "F type engines" at the top of the page....

 

 

 

 

It is fascinating to read about the British actually REMOVING said regulator on their Allison P51s (don't see a document where they did that for Tomahawks, Kityhawks, hmm) to obtain 72" of boost FOR 20 MINUTES.

 

It is also fascinating that they wanted to build an aircraft carrier out of ice and wood pulp.

 

It did not happen either, though.

 

https://en.wikipedia.org/wiki/Project_Habakkuk

[=362nd_FS=RoflSeal]

But removing the regulator did happen according to that report.

[Crump]

P-51 is not a P-40...

 

Nor is the RAF and USAAF the VVS....

[MiloMorai]

I guess Crump has never been in the situation where he was told to do something and the paper work will follow later.

[Crump]

April 1943 Allison Operating Instructions for War Emergency Power Rating:

 

 

 

 

Part of the issue is apples for oranges..

 

Folks are using experience gained on a completely different mission parameters and trying to apply to a fighter mission.  

 

The RAF program was tactical reconnaissance.

 

 

 

Wing Commander Peter Dudjeon, a former squadron commander of one of the Army Cooperation Units, was contacted on 31 May, 1943, for the purpose of obtaining information on their daylight intrusion raids (Rhubarbs) using the North American Mustang I and IA aircraft. W/C Dudjeon was most helpful and cooperative in spite of the fact that the Army Cooperation Activities were being, that day, taken over by the R.A.F. Fighter Command and all personnel was engaged in moving to the new post. Additional time was spent with him after he had moved to the new headquarters.

 

 

 

 

 This phase of the Army Cooperation effort started as a photo reconnaissance operation using the Mustang I fitted with two cameras; a vertical camera in a quick detachable mount and an oblique camera mounted aft of the pilot’s head and “shooting” out the left side of the canopy through a small hole cut in the plexiglass. The cameras were automatic in their operation and controlled by the pilot.

 

 

It evolved into a successful low level raid and armed reconnaissance unit.

 

The general flight profile:

 

 

 

 The flight from the home base to within 40 miles of the point of crossing the enemy coast is made at 200 IAS, 1100 R.P.M. and 30.0” Hg. at between 25 to 50 feet altitude. Upon reaching the above mentioned point, the power is increased to maximum cruising (250-275 mph – 2600 R.P.M. – 34.5” Hg.) and left there during the entire time over enemy territory and until 40 miles away from enemy coast on the return trip. If a landfall is not made within 5 miles of the predetermined point at which the enemy coast was to be crossed, then the flight should return home immediately because the entire flight plan will be thrown off too much, and also, since the entry point is chosen with careful regard for the flak map, there is apt to be serious trouble from this cause.

 

 

 

 

The pilots are schooled to run rather than fight because their main objective is the destruction of ground targets, not to fight enemy aircraft. 

 

 

There is a huge difference in stress on the engine.  A fighter mission where the engine is going from maximum power to idle multiple times in a dogfight is MUCH more stressful on the engine that just setting a steady manifold pressure and rpm.

 

It is harder on the engine to go from 56"Hg at 3000 rpm to idle and then back again that it is to run 60"Hg at 3000 rpm for a steady period once.

 

I think that is why you see this high boost setting that is not repeated in any of the fighter variant operating instructions.  

 

The extremely high boost is tailored for the mission the pilot and the airplane were being asked to perform.  If you researched the units history, I bet you would find the authorizations from Allison to use that 60" to 70" for that unit.

 

Interesting stuff!!

 

http://www.wwiiaircraftperformance.org/mustang/e-geh-16.html

[Dave]

What these documents (Han's post above) provide are settings to be used for aircraft longevity. When you exceeded them the engine did not spontaneously explode. Nobody - repeat NOBODY - observed them strictly in the field. They are values produced ultimately by the manufacturer and have varying built-in factors for manufacturer arse-covering. This is precisely why Allison revised their operating data several times on the basis of field data from North African squadrons pushing their aircraft beyond published "limits" to give themselves as much edge as possible. The RAF and RAAF units proved that Allison were overly conservative in their initial estimates based on the fact that their thinking was geared to engine longevity rather than surviving the fight to fly again. A pilot doesn't care how many hours are left on the engine main bearings after they are shot down.

 

A separate issue is the use of 1943 training manuals. Training manuals are even more conservative. For an example read the prohibited manoeuvres section of any training flight manual. If these restrictions were applied to combat there would be no dogfights for fear of exceeding rolling G limits.

I have returned more than one aircraft with the G-limits exceeded. I did have to write it up and the ground crew weren't happy. The wings didn't fall off.

 

I think the use of Rechlin record-attempt performance data for the 109 alongside manufacturer arse-plating and training manual limits for the P40E (to the exclusion of very well documented combat practices) is flawed and unjustifiably hobbles VVS pilots who already fly at a significant performance deficit.

Edited March 24, 2016 by Dave

[Dave]

 

 

The RAF program was tactical reconnaissance.

 

 

They must have forgotten to tell 250SQN, 112SQN and 3SQN RAAF.

[Crump]

 

 

A separate issue is the use of 1943 training manuals.

 

Only issue is NONE of the engine setting are from the training manual.....

 

Training Manual:

 

 

Clearly labeled....Training Manual

 

 

It is the OPERATIONAL MANUAL....

 

 

 

What these documents (Han's post above) provide are settings to be used for aircraft longevity.

 

No, they are for the airplane to have the best change to perform its designed mission and come home. 

 

 

A pilot doesn't care how many hours are left on the engine main bearings after they are shot down.

 

He does care when the fan up front stops turning in flight....

[Dave]

Only issue is NONE of the engine setting are from the training manual.....

I was referring to the source documents posted by Han in post #33 of this thread.

He cites a 1943 training manual, a 1942 Russian training manual with figures pulled straight from the 1941 Allison manual and a 1942 training order issued to instructors for training of aircrew on type.

 

No, they are for the airplane to have the best change to perform its designed mission and come home.

No, they are to ensure the engines reach planned MTBF with sufficient safety margin to protect the manufacturer.

 

He does care when the fan up front stops turning in flight....

He does. Perhaps I was too abstract for you. When choosing between not reducing the remaining flight hours of the engine by an accelerated 20 hours from 1500 to 1480 and shaving 3 seconds off his corner-speed turn time to not take a 20mm round through his torso, he chooses to push the engine every time.

 

I get the impression you are an armchair "pilot" who has never had to explore envelope and airframe limits for real. These concepts are meat and potatoes for military aircrew.

Edited March 24, 2016 by Dave

[Venturi]

P-51 is not a P-40...

 

Nor is the RAF and USA the VVS...

Correct. From the documentation early P51s had -39 Allisons with regulators installed from factory. The P40s with -39 Allisons were "retrofittable" with regulators but were never manufactured with them.

 

When installed on P51s, the aircrews hated the regulators because they prevented full use of the engine's capabilities. So they uninstalled them. If you get a General asking for official permission, you know it's already happening "on the ground".

 

What follows from this is that P40s with -39 Allisons likely never had them installed in the field. Why would anyone want a downgrade?

 

Certainly the regulators weren't installed from the factory. And THAT means the VVS likely never had any with regulators. Which means the VVS had P40Es which could run 72" of boost at sea level.

 

And we can already see from multiple period reports that western Allied aircrews were aware of the fact that the engines could run much higher MP and give much higher power than the official training manuals, and that they did so regularly with awareness and respect of the engine's true limitations.

 

So to say that the VVS pilots did not ALSO do so is to assume that the VVS pilots either

 

A) were incapable of discovering and using the "hidden" potential of the -39 Allison as compared to the "Manufacturer Approved" settings, which required them only to push the throttle more forward,

 

Or,

 

B) knew about them but were so hide-bound to operating "by-the-book" that they never attempted to do so.

[6./ZG26_Klaus_Mann]

Ok, you guys have confused me to the point at which I don't know what each of you wants anymore (please only if you have the game)

 

Could each of the participants offer their ideas for the (non)-solution to the P-40 Problem please and the Sources you go by, so we can conclude this finally at least for this thread.

 

Please state all Logical Engine Stages in: 

 

#N

Name (Combat, Climb, Emergency or whatever)

Manifold Pressure (MAP): N inches

Revolutions per Minute (RPM): N RPM

Duration in Minutes you would suggest, meaningful and in the context of the game (No Continuous 70" etc)

 

This would make it easier to see through everything

[Venturi]

Combat 44-56" 3000rpm 20min

Emergency 57-72" 3000rpm 5min, 72" unachievable above 500m as pressure declines with increasing alt

 

Both recoverable

Edited March 29, 2016 by Venturi

[Fern]

Combat 44-56" 3000rpm 20min

Emergency 57-72" 3000rpm 5min, 72" unachievable above 500m as pressure declines with increasing alt

 

Both recoverable

 

This or they get rid of the POS from the game and give refunds

[JtD]

Variable, random engine damage based on engine load instead of timed failures.

[FuriousMeow]

Can't do Dec '42 or April 1943 settings/documentation for the P40/Allison when the 109G-2 is restricted to 1.3ATA in late '42/early '43 when it was cleared for 1.42  mid '43.

 

As much as I'd love to see the P40 get a boost, not going to work based on Dec '42 and April '43 data when it is operating winter '41/'42 and the 109G-2 is operating at it's limits for the timeframe it is in. If there is winter '41/'42 data showing the same operations then that is great, but there's a huge difference in ~11 months.

 

The P40's engine settings is based around Battle of Moscow time frame, just as the 109G-2's engine limits are based around Battle of Stalingrad time frame.

 

Can't play loose with one and strict with the other, and since we are covering those time frames/Battles - we need to keep it accurate to performance.

Edited March 29, 2016 by FuriousMeow

[Venturi]

Of course I'd agree with this too... 

 

Variable, random engine damage based on engine load instead of timed failures.

[Venturi]

The DB605 required someone tinker with the engine boost regulator to change the boost pressure, the V1710-39 did not. All you had to do to get 72" was fly low, push the RPM to max, and give it full throttle.

 

The Soviets did that just as soon as they flew it, just like they pushed the P39 and every other aircraft they had. And the documents show that the Allison could take it.

 

Can't do Dec '42 or April 1943 settings/documentation for the P40/Allison when the 109G-2 is restricted to 1.3ATA in late '42/early '43 when it was cleared for 1.42  mid '43.

 

As much as I'd love to see the P40 get a boost, not going to work based on Dec '42 and April '43 data when it is operating winter '41/'42 and the 109G-2 is operating at it's limits for the timeframe it is in. If there is winter '41/'42 data showing the same operations then that is great, but there's a huge difference in ~11 months.

 

The P40's engine settings is based around Battle of Moscow time frame, just as the 109G-2's engine limits are based around Battle of Stalingrad time frame.

 

Can't play loose with one and strict with the other, and since we are covering those time frames/Battles - we need to keep it accurate to performance.

[6./ZG26_Klaus_Mann]

Can't do Dec '42 or April 1943 settings/documentation for the P40/Allison when the 109G-2 is restricted to 1.3ATA in late '42/early '43 when it was cleared for 1.42  mid '43.

 

As much as I'd love to see the P40 get a boost, not going to work based on Dec '42 and April '43 data when it is operating winter '41/'42 and the 109G-2 is operating at it's limits for the timeframe it is in. If there is winter '41/'42 data showing the same operations then that is great, but there's a huge difference in ~11 months.

 

The P40's engine settings is based around Battle of Moscow time frame, just as the 109G-2's engine limits are based around Battle of Stalingrad time frame.

 

Can't play loose with one and strict with the other, and since we are covering those time frames/Battles - we need to keep it accurate to performance.

You fail to see the cause and effect nature of both engines, as it is reversed.  

The DB605s had massive engine problems and until further notice were forcibly restricted. 

The Allisons Overperformed the Manuals Massively, thus the Manuals were at some point Updated to fit Reality. 

 

I already made the example that the Manuals were so extremely conservative, it would be like restircting the DB605 to 1 Minute at 1.3ata and 5 at 1.15ata and I'm most certain the german Pilots would have pushed them through the wire with surprisingly little ill-effects. 

 

The early Manuals simlply don't give t effective Combat Limitations, unlike the Daimler Ben guys who simply took out one extremely  high power setting, but left in the other still very good power settings in, because germany was at war for almost 7-8 years at that point already, America wasn't. 

The german engineers therefore knew how to still create a combat effective powerplant, while the American Counterparts were still thinking in terms of Engine Longevity in training etc.

Edited March 29, 2016 by 6./ZG26_Klaus_Mann

[Dave]

You fail to see the cause and effect nature of both engines, as it is reversed.  

The DB605s had massive engine problems and until further notice were forcibly restricted. 

The Allisons Overperformed the Manuals Massively, thus the Manuals were at some point Updated to fit Reality. 

 

I already made the example that the Manuals were so extremely conservative, it would be like restircting the DB605 to 1 Minute at 1.3ata and 5 at 1.15ata and I'm most certain the german Pilots would have pushed them through the wire with surprisingly little ill-effects. 

 

The early Manuals simlply don't give t effective Combat Limitations, unlike the Daimler Ben guys who simply took out one extremely  high power setting, but left in the other still very good power settings in, because germany was at war for almost 7-8 years at that point already, America wasn't. 

The german engineers therefore knew how to still create a combat effective powerplant, while the American Counterparts were still thinking in terms of Engine Longevity in training etc.

Nailed it.

 

The Allison V1710-39 wasn't upgraded to achieve the figures given. It was capable of them at the time of BoM but the manufacturer's operating guidelines were still extremely conservative at that time. Allison later brought their documentation into line with observed capability - not the other way around. This differs significantly from the situation with the DB605. I think Klaus got the reason right here in his comparison of the two manufacturer's relative recent combat experience. I would be happy for both - in fact all - engine limitations in game to be based more heavily upon front line units' empirical evidence than manufacturers' warranties when they diverge this substantially.

Edited March 30, 2016 by Dave

[Dave]

Combat 44-56" 3000rpm 20min

Emergency 57-72" 3000rpm 5min, 72" unachievable above 500m as pressure declines with increasing alt

 

Both recoverable

+1 for the ~20 minutes at MIL and ~5 minutes at WEP.

 

I reckon the game engine supports the maximum altitude for max MP being governed by ambient pressure (read temperature) rather than altitude. This already seems to be represented in the difference in engine performance between summer, autumn and winter maps - unless (and I really doubt this) they use a separate discrete performance map, one per season.

Edited March 30, 2016 by Dave

[Venturi]

Quite possibly the game engine uses temp to generate pressure, unless its some sort of global setting per map.

 

Now stand back, I'm going to do physics:

 

Temperature affects gas density. Cold gas is denser, so colder temperatures will increase the atmospheric pressure at any given altitude compared to a warmer temperature. This does affect the boost achieved at a given altitude, speed (if the supercharger is set up to take advantage of the ram-effect, which the Allison and most were), and throttle setting; as well as the maximum boost possible (for a engine such as the Allison without a boost regulator).

 

But, another major reason why cold air generates more power in supercharged internal combustion engines is because a cold gas will contain less water vapor per unit volume than a warmer gas, given they are at equivalent pressures.

 

Water does not participate in combustion. This means the cold gas will consist of more oxygen per unit volume than the warm gas. Thus, the moles of reactant in a combustion reaction are greater for a given volume and pressure of cold gas than warm gas, and thus the combustion reaction produces more energy.

 

Regardless of all the above, which does play a big role, the altitude of the aircraft is the primary determinant of the atmospheric pressure it experiences, by a long ways.

 

Source: me,

4 years of university chemistry

20 years of building racing engines

6 years of giving medical therapy with pressurized gasses

 

+1 for the ~20 minutes at MIL and ~5 minutes at WEP.

I reckon the game engine supports the maximum altitude for max MP being governed by ambient pressure (read temperature) rather than altitude. This already seems to be represented in the difference in engine performance between summer, autumn and winter maps - unless (and I really doubt this) they use a separate discrete performance map, one per season.

Edited March 30, 2016 by Venturi

[Crump]

 

 

Your comments make it very plain you have little to no experience with boosted a/c engines nor their components.

 

I only have worked on them AND authorized by the aviation authority of my country to return them to airworthiness.

 

How about you?

 

The limitations are very clearly published.  

 

 

 

P-40E, no regulator until this technical order, where only those in combat zones would recieve it, aircraft in training squadrons wouldn't.

 

 

So are you modeling P-40's in the training units???

 

 

 

Certainly the regulators weren't installed from the factory. And THAT means the VVS likely never had any with regulators. Which means the VVS had P40Es which could run 72" of boost at sea level.

 

 

And the instructions are crystal clear to any pilot, mechanic, or engineer....

 

No regulator = NO EMERGENCY WAR POWER setting.  End of story.

 

The engines without regulators are limited to the lower power settings of Take Off and Military Power.  It is that simple.

 

V-1710F3R Engines as of April 1943 without regulators are limited to a maximum of 42" at military power and 45.5 at take off rating. 

 

 

 

Klauss, you made the point that Allison was too conservative while DB was not conservative enough.   I do not think that is the case.  

 

The Allison engine company limitations were undermined by a few no so savvy individuals who thought they knew more than the engineers.  That is why the engine got the reputation as the "Allison Time Bomb".

 

 

 

I get the impression you are an armchair "pilot" who has never had to explore envelope and airframe limits for real. These concepts are meat and potatoes for military aircrew.

 

No, like my many colleagues and coworkers who were fighter pilots, I am just a professional pilot who takes the airplane were it needs to go to accomplish the mission assigned to me.

 

Destroying the airplane and killing myself and crew members is not accomplishing that mission.  In fact, it is the opposite.

[6./ZG26_Klaus_Mann]

I only have worked on them AND authorized by the aviation authority of my country to return them to airworthiness.

 

How about you?

 

The limitations are very clearly published.  

 

So are you modeling P-40's in the training units???

 

And the instructions are crystal clear to any pilot, mechanic, or engineer....

 

No regulator = NO EMERGENCY WAR POWER setting.  End of story.

 

The engines without regulators are limited to the lower power settings of Take Off and Military Power.  It is that simple.

 

V-1710F3R Engines as of April 1943 without regulators are limited to a maximum of 42" at military power and 45.5 at take off rating. 

 

Klauss, you made the point that Allison was too conservative while DB was not conservative enough.   I do not think that is the case.  

 

The Allison engine company limitations were undermined by a few no so savvy individuals who thought they knew more than the engineers.  That is why the engine got the reputation as the "Allison Time Bomb".

 

 

No, like my many colleagues and coworkers who were fighter pilots, I am just a professional pilot who takes the airplane were it needs to go to accomplish the mission assigned to me.

 

Destroying the airplane and killing myself and crew members is not accomplishing that mission.  In fact, it is the opposite.

I still have trouble with one point. 

If you give me two settings, one of which is much lower than the other, but the same time limitations apply, how can I understand this?

Do I have to choose between 42", 45.5" and 56" and anything between is just 5 Minutes? Why then have Military Power at all in this?

It just makes no sense at all. 

Is anything above 42" just 5 Minutes, no matter what? So if I run 42" it's the same as 56" or higher?

It only makes sense if they added up, so 15 Minutes at 42", 10m at 45.5" and 5 at 56". 

 

How does Allison expect the pilots to undertand this?

 

Edit: 

The German Manuals are quite clear in this and the Settings Subtract from one another. 

You have: (DB601A)

Höchstleistung for 1 Minute 1.4ata

Kurzleistung for 5 Minutes at 1.3ata

Steig und Kampfleistung for 30 Minutes at 1.23

Dauerleistung at 1.15

 

So if you use 1.4ata for a Minute you still have 4m at 1.3ata and then 25 Minutes at 1.23ata

 

These are settings that don't contradict each other and hurt ma brains. 

Edited March 30, 2016 by 6./ZG26_Klaus_Mann