Crump Posted August 1, 2016 Posted August 1, 2016 Granted, it's not an E model but rather an M, captured by Finland: The P-40M is nothing even close to the P-40E. The P-40M uses the same engine as the last production variant, the P-40N.
Farky Posted August 2, 2016 Posted August 2, 2016 (edited) that Allison handbook (ALD-3F2) is not official document, it clearly states "For information only". So, it cannot approve a thing. It is more of a recomendations, not order. This is not official user document and users allow limits for engines. In cooperation with factory, of course, but users have last word on limits. No, It is the the official document on how the USAAF operated their Allison engines. It is not official document for USAAF. Here are limits recommended in ALD-3F2 vs limits in USAAF pilot's manuals ( i.e. Technical Orders) - I check limits in ALD-3F2 against USAAF pilot's manuals ( i.e. Technical Orders) and results photoshopped into table from ALD-3F2 - The use of 56"Hg as War Emergency Power does REQUIRE the MAP regulator and therefore the specifications with "streamlined manifolds" MUST have a MAP. OK, I understand now - you are talking about that particular power table for P-40E, not in general. Yes, you are right, use of War Emergency Rating does require automatic MAP regulator. Next time you can just write something like "The use of 56"Hg as War Emergency Power does REQUIRE the automatic MAP regulator and therefore the specifications with this limit MUST have this device". Just saying. Venturi, are you sure you are not using 45.5"Hg and experiencing engine failure after a few minutes? 45.5"Hg is a Take Off rating.....NOT Military Power (5 minute limit). You forget mention one little detail - time limit for Take Off rating was also 5 minutes. So, you can use 45.5 in Hg and engine is able to withstand it without failure. What about that Dec 1942 spec sheet approving 56"? http://forum.il2stur...weird/?p=369889 As I wrote before, this specific sheet was issued in September 1944, not December 1942. It is sheet from pilot's manual issued May 1943 and revised September 1944. Specification AN-H-8 (issued Dec.18,1942) was just general specification about charts and do not authorise any engine limits. All USAAF engine limits were approved via Technical Orders, that was the only way. If you take a look on this sheet for P-51D, you will find same date and this airplane (and engine) does not exists in Dec 1942 - Flight manual for P-40E ( Technical Order No. 01-25CF-1) issued February 25, 1943 and revised 4-10-43 do not mention WER at all and specifically states - 44.6 in Hg / 3000 rpm for 5 minutes only as Military Power. I imagine by December 1942, it would be rare to encounter a P-40E on the frontline without a MAP. For a second time - automatic pressure regulator were not installed into P-40Es until the autumn of 1943, when T.O. No. 1-25C-112 ( Instalation of Automatic pressure regulator) was issued. The stops achieve the preset manifold pressure of 52"Hg if the engine does not have a MAP in the V-1710F3R series. You simply cannot select more than what the engine is set too. Wrong, there were no such stops on engines without automatic regulator. Engine not equipped with a MAP were limited to 52"Hg for the 5 minute emergency power. This gives them a 4"Hg buffer to prevent overboosting. Wrong, V-1710-39 were not limited to 52 in Hg. Not by users, you will not find such limit in power charts in pilot manuals or any other technical orders. About 4 in Hg buffer - is this only your theory, or you read this in some document? Edit: Here are limits recommended in ALD-3F2 vs limits in USAAF pilot's manuals ( i.e. Technical Orders) changed to I check limits in ALD-3F2 against USAAF pilot's manuals ( i.e. Technical Orders) and results photoshopped into table from ALD-3F2. Edited August 7, 2016 by Farky
Venturi Posted August 3, 2016 Posted August 3, 2016 (edited) The engine could withstand much more power than 44.6" or 45.5" and still keep on ticking, the problem is in the flux of the power load on the engine that could spike MAP well beyond 56". However, the current reality of hard coding the sim so that the engine fails at 3000rpm (regardless of MAP) or at 2min of 56" is not reality. The reality is that the engine could take these levels of power (they were rated 5min 56" with MAP regulator), it's just that there was much less safety margin for dynamic changes in MAP without the regulator. That and engine management simplification were the reason they were installed. That's the way failure should be coded. In the sim, the pilot should be able to run 56" or slightly more for 5min or (I would argue) even greater, or 3000rpm at lower MAP for even longer times, without destroying his engine. That is because as sim pilots we are much better able to focus on and control engine parameters than the real pilots who were dealing with sensory overload. To really fix this will require more nuanced engine limit modeling, with limit timer resets or a total and more realistic revamp of the way engine limits are handled in general. Edited August 3, 2016 by Venturi
Dakpilot Posted August 3, 2016 Posted August 3, 2016 As I wrote before, this specific sheet was issued in September 1944, not December 1942. It is sheet from pilot's manual issued May 1943 and revised September 1944. Specification AN-H-8 (issued Dec.18,1942) was just general specification about charts and do not authorise any engine limits. All USAAF engine limits were approved via Technical Orders, that was the only way. If you take a look on this sheet for P-51D, you will find same date and this airplane (and engine) does not exists in Dec 1942 - P-51.JPG Flight manual for P-40E ( Technical Order No. 01-25CF-1) issued February 25, 1943 and revised 4-10-43 do not mention WER at all and specifically states - 44.6 in Hg / 3000 rpm for 5 minutes only as Military Power. Thanks for finally clarifying this "1942" document without shadow of doubt, it has been quoted for so long in this discussion I also think it gives a valuable lesson for all of us, in that a thorough understanding of military documents is necessary, and that things are not always as they seem at first glance, or even considerable exposure Cheers Dakpilot
JG13_opcode Posted August 4, 2016 Posted August 4, 2016 (edited) But let's say you're right and its the 50" gauge only. That doesn't mean the plane could not have used the Dec 1942 specification of 56" safely. How can you safely measure something if your instruments go off-scale? That would be like telling the cop you were going 80 but your speedometer only goes up to 65. Edited August 4, 2016 by JG13_opcode
Dave Posted August 5, 2016 Posted August 5, 2016 How can you safely measure something if your instruments go off-scale? That would be like telling the cop you were going 80 but your speedometer only goes up to 65. The analogy is poor anyway because it's the cop telling you your measured velocity. But your example presents the opposing view well - try telling a cop you couldn't possibly have been doing 80 because your speedo only reads to 65 and see how far you get.
6./ZG26_Klaus_Mann Posted August 5, 2016 Author Posted August 5, 2016 I have started a Monster apparently. I don't know what to think anymore.
JG13_opcode Posted August 5, 2016 Posted August 5, 2016 The analogy is poor anyway because it's the cop telling you your measured velocity. But your example presents the opposing view well - try telling a cop you couldn't possibly have been doing 80 because your speedo only reads to 65 and see how far you get. Fair point. Poor analogy. Still, I don't see how Venturi's statement makes sense. You can't safely measure something if your instrument doesn't go that high.
Venturi Posted August 5, 2016 Posted August 5, 2016 (edited) I think you should re-read Dave's post and think more carefully. Edited August 5, 2016 by Venturi
JG13_opcode Posted August 5, 2016 Posted August 5, 2016 (edited) I think you should re-read Dave's post and think more carefully. Why so aggro? Assuming I'd read it the first time, which I hadn't. I guess if they're taking the gauges out and marking them at calibrated intervals that could work. But that's not what I thought you were describing. Edited August 5, 2016 by JG13_opcode
Crump Posted August 6, 2016 Posted August 6, 2016 It is not official document for USAAF. Here are limits recommended in ALD-3F2 vs limits in USAAF pilot's manuals ( i.e. Technical Orders) - That is simply some photoshopped baloney. Someone has deceptively photoshopped out the original Allson instructions by removing the Rated Altitude column and substituting the "USAAF Manual Ratings". Here is your photoshopped document: Here is the UNPHOTOSHOPPED document, right out the Overhaul instructions. These ARE the official Operating Limitations of the Engine. Allison holds the engine Type Certificate and the USAAF complied with that Type Certificate. End of Story..... I think you should re-read Dave's post and think more carefully. Great demonstration of the widespread use of the MAP regulator and it's link to the use of 56"Hg! Really shows the fact that the Type Certificate Operating Limitations were adhered too by EVERYONE!! Good stuff Venturi. Post some more! Unfortunately a memo "suggesting" is not proof of anything outside of the fact they definitely had the MAP regulators on their aircraft using 56"Hg just like the manual instructs!
MiloMorai Posted August 6, 2016 Posted August 6, 2016 Table I: engines equipped with turbosuperchargers Table II: engines not equipped with turbosuperchargers
Crump Posted August 6, 2016 Posted August 6, 2016 It is not official document for USAAF. Here are limits recommended in ALD-3F2 vs limits in USAAF pilot's manuals ( i.e. Technical Orders) - HA ha ha!! That photoshopped page you posted is not even for the P-40E engine. It is the P-38!! Anyway...here is that one UNPHOTOSHOPPED!! Yes, it is the official Operating Limitations that the USAAF used. It will all align if you look at the correct timeline!! hanks for finally clarifying this "1942" document without shadow of doubt, it has been quoted for so long in this discussion
MiloMorai Posted August 6, 2016 Posted August 6, 2016 Maybe you should quote the Table II posted in Post 533 crump
Venturi Posted August 6, 2016 Posted August 6, 2016 (edited) No one is arguing that 56" was the published limit. But it didn't stop the aircrews of P-51s with V-1710-39 with factory MAP regulators, from removing said regulators to be able to boost the engines much higher... without immediate failure... Edited August 6, 2016 by Venturi
Crump Posted August 6, 2016 Posted August 6, 2016 But it didn't stop the aircrews of P-51s with V-1710-39 with factory MAP regulators, from removing said regulators to be able to boost the engines much higher... without immediate failure... Oh!! Where do they remove the MAP regulators??? I do not see anything saying they did that. I just see a memo suggesting it.
Venturi Posted August 6, 2016 Posted August 6, 2016 Oh!! Where do they remove the MAP regulators??? I do not see anything saying they did that. I just see a memo suggesting it. The P40E never had one... since the technical order for refit was in 1943...
Crump Posted August 6, 2016 Posted August 6, 2016 No one is arguing that 56" was the published limit. You do know that by April 1, 1943, some Allison V-1710's were running 60" with a MAP regulator. Just not the V-1710F3R found in the P-40E series. The P40E never had one... since the technical order for refit was in 1943... And it never ran 56"Hg until it was retrofitted with one.....
Venturi Posted August 6, 2016 Posted August 6, 2016 Sure, and the V-1710-33 was being run at 60" by the Flying Tigers... And it never ran 56"Hg until it was retrofitted with one..... Buckle those straps down...
Crump Posted August 6, 2016 Posted August 6, 2016 Sure, and the V-1710-33 was being run at 60" by the Flying Tigers... Oh! Fantastic! You can show us the official documents I am sure.... Right??
Crump Posted August 6, 2016 Posted August 6, 2016 The P40E never had one... since the technical order for refit was in 1943... Well even the RAAF was discussing getting them in August of 1943 for their P-40E's!!! Why wouldn't the USAAF have every P-40E in the inventory equipped with a MAP by 1944?? I don't see how they could not have them retrofitted by then.
Farky Posted August 7, 2016 Posted August 7, 2016 (edited) It is not official document for USAAF. Here are limits recommended in ALD-3F2 vs limits in USAAF pilot's manuals ( i.e. Technical Orders) - That is simply some photoshopped baloney. Someone has deceptively photoshopped out the original Allson instructions by removing the Rated Altitude column and substituting the "USAAF Manual Ratings". Seriously? Of course this pictures are photoshopped, by me. I check limits in ALD-3F2 against USAAF pilot's manuals and results photoshopped into table from ALD-3F2. Is it clear now? I was pretty sure that it's obvious, probably not. I will edit my previous post then. I can also check manuals from other users of V-1710-39, like this one for RAF Mustang issued 5th August 1943 - Still not the same as ALD-3F2. You can do same thing, feel free to compare USAAF manuals with ALD-3F2. These ARE the official Operating Limitations of the Engine. Allison holds the engine Type Certificate and the USAAF complied with that Type Certificate. Then you can show power table from USAAF manual with same limits, right? These are operation limits recommended by Allison. We can call them "Allison approved limits" if you want (not official, because ALD-3F2 is "For information only"), but these limits were not same for USAAF/ RAF/ RAAF etc. engines. Point is - this is not modern civil aviation, military aviation in WWII was working little bit different than you think. And even in modern civil aviation, you are not allowed use "For information only" documents, I am pretty sure you know that. That photoshopped page you posted is not even for the P-40E engine. It is the P-38!! Don't be silly, I posted two pages and you know that. The P40E never had one... since the technical order for refit was in 1943... And it never ran 56"Hg until it was retrofitted with one..... It run sometimes on even higher MAP, long time before War Emergency Rating exist. Combat report of Sgt. Butler (75. sqn. RAAF), 25th April 1942, Kittyhawk A29-48 ( ex-USAAF P-40E 41-5535) - The P40E never had one... since the technical order for refit was in 1943... Well even the RAAF was discussing getting them in August of 1943 for their P-40E's!!! Why wouldn't the USAAF have every P-40E in the inventory equipped with a MAP by 1944?? I don't see how they could not have them retrofitted by then. There is nothing about getting automatic manifold pressure regulators for P-40E. Just saying. Edit: typo Edited August 7, 2016 by Farky 5
Crump Posted August 7, 2016 Posted August 7, 2016 eriously? Of course this pictures are photoshopped, by me. I check limits in ALD-3F2 against USAAF pilot's manuals and results photoshopped into table from ALD-3F2. Is it clear now? I was pretty sure that it's obvious, probably not. I will edit my previous post then. Your photoshop does not line up the timeline. Why don't you just post the actual documents instead of trying to convince everyone on circumstantial evidence. This is not a crime scene. It is airplanes, one of the most highly regulate maintenance machines on planet earth. It is simply a fact the type certificate holders limitations ARE the definitive source. The Commonwealth is a convention signatory. t run sometimes on even higher MAP, long time before War Emergency Rating exist. Combat report of Sgt. Butler (75. sqn. RAAF), 25th April 1942, Kittyhawk A29-48 ( ex-USAAF P-40E 41-5535) - It is a closed manifold system Farky. If you do not pull it back, it will not maintain the limits. That is the purpose of the MAP regulator. You dive from 11,000 feet to 4,000 feet with the right atmospherics and you will get exactly the same conditions the Allison Engineer warned about. What you found in the combat report Farky is exactly why this memo was put out by Allison. The difference is you are using it as evidence of some super secret field modification overboosted ignore the manufacture limit phantom rating. It is not. It is simply a function of the physics of having a closed manifold pressure system. There is nothing about getting automatic manifold pressure regulators for P-40E. Just saying. In PLAIN english it is written that the P-40N already come with the manifold pressure regulator. The P-40E's do not. It is intended to install the MAP regulator later in the P-40N contract. What exactly are they going to install them on?? Are they going to put TWO MAP regulators on each P-40N?? HA ha aha?? Allison engineers warning of the same conditions found in your combat report..... Allison abuse.pdf
MiloMorai Posted August 7, 2016 Posted August 7, 2016 What is the difference between a manifold pressure regulator and an automatic engine control unit?
JtD Posted August 7, 2016 Posted August 7, 2016 (edited) It's a combined throttle / prop pitch (rpm) control. Farky, thank you for your patience and the easy to understand and informative posts. Edited August 7, 2016 by JtD
Crump Posted August 7, 2016 Posted August 7, 2016 A manifold pressure regulator is basically a pressure relief valve. It maintains a maximum pressure in the manifold. An automatic engine control unit usually has a manifold pressure regulator as a subcomponent. Automatic engine control is more sophisticated and handles timing, propeller rpm, and fuel metering. In a simple automatic engine control with hard linkage, the throttle position to achieve a desired power level will change with atmospheric conditions. In a sophisticated automatic engine control system, the linkage will adjust for atmospheric conditions such that throttle position will always correspond to a power setting no matter what the atmospherics. That is why in an FW-190, "Start u Notleistung" can be labeled on the throttle quadrant. That throttle position will always produce 1.42ata at 2700U/min in heat of summer or the dead of winter. Here we have the P-47 throttle quadrant. It is only labeled "Open and Close" because the actual position of the throttle lever in relation to the power setting on the engine will change based on atmospheric conditions! Depending on the atmospherics, it is very easy to overboost any engine. That does not mean you are not violating the operating limits and risking damage to your engine. Overboosting is simply something pilots avoid because we like to live thru the day!!
Crump Posted August 7, 2016 Posted August 7, 2016 (edited) Then you can show power table from USAAF manual with same limits, right? Here is your fallacy. You do not have to operate an aircraft to the limits specified by the Type Certificate. You can always take a lower self imposed limit, you just cannot exceed the published limits. I agree with you in that I have never seen any USAAF P-40 document showing 52"Hg. I have seen many of the them with the exact same instructions found in the RAF Operating Instructions for the P-40E you posted: Using a lower limit adheres to Aviation Convention and the Type Certificate Instructions. Government aircraft maintain their own airworthiness and that means they must comply with the type certificate. Perhaps the reluctance of the services to use the full 52"Hg had to do with the manifold pressure gauges in service and the reputation for a lack of reliability the engine was getting in service? Edit'd: Left out a key pronoun "you" Edited August 7, 2016 by Crump
Crump Posted August 7, 2016 Posted August 7, 2016 Once more, achieving the 45.5"Hg is a very easy adjustment. You do not have to fiddle with turning a screw a set number of degrees to achieve the 52"Hg. You simply mount the 52"Hg linkage rods and bottom out the adjusting screws!! No fuss, no mess, no time spent tinkering.....no looking at charts and trying to turn a silly screw a set number of degrees buried in an engine compartment. You would not even have to run the motor to confirm the setting was correct. Bottom out the screws and that is what you get!!! If it does not achieve the 45.5"Hg....the pilot will complain... I am kidding. They would run a check even if they just bottomed out the screws but it is a very easy adjustment and does not violate the Type Certificate.
Farky Posted August 7, 2016 Posted August 7, 2016 It is simply a fact the type certificate holders limitations ARE the definitive source. The Commonwealth is a convention signatory. Today, yes. Not in WWII, it wasn't so simple. What you found in the combat report Farky is exactly why this memo was put out by Allison. The difference is you are using it as evidence of some super secret field modification overboosted ignore the manufacture limit phantom rating. It is not. It is simply a function of the physics of having a closed manifold pressure system. That combat report is evidence of using overboost out of the manual limits. It is about what was possible, not what was allowed. That's it, I never say anything about field modification. Super secret field modification? Good one, I like it. I do not know why you assume that I do not know how an engine works without automatic MAP regulator, but I know how it works. There is nothing about getting automatic manifold pressure regulators for P-40E. Just saying. In PLAIN english it is written that the P-40N already come with the manifold pressure regulator. The P-40E's do not. It is intended to install the MAP regulator later in the P-40N contract. What exactly are they going to install them on?? Are they going to put TWO MAP regulators on each P-40N?? HA ha aha?? No, it is written that the P-40N already come with the manifold pressure regulator and it is intended to install automatic engine control units at some time later in the P-40N contract. And that's exactly what happened - first P-40Ns were equipped with standard automatic manifold pressure regulators ( aircraft 42-104429 through 42-106405, first P-40N-1CU through last P-40N-15CU), then Curtiss installed new automatic engine controls ( airplane 42-106406 and subsequent, first P-40N-20CU and subsequent ). You wonder why MiloMorai asked what is the difference between a manifold pressure regulator and an automatic engine control unit? Well, you now probably know why. Some info about automatic engine control in P-40N, for those who would be interested - Here is your fallacy. You do not have to operate an aircraft to the limits specified by the Type Certificate. You can always take a lower self imposed limit, you just cannot exceed the published limits. ... Right, you cannot exceed the published limits. There is a problem, right there. Let's check data from picture below ( it is manual for RAF Mustang, not P-40E btw) against ALD-3F2, shall we ? Take off : ALD-3F2 - 45.5 in Hg/ 3000 rpm ( 5 min limit ) vs RAF manual - 45.5 in Hg/ 3000 rpm ( max to 1000 ft.) - let's call it MATCH. War emergency rating (Emergency boost in UK) : ALD-3F2 - 56 in Hg/ 3000 rpm ( 5 min limit ) vs RAF manual - 56 in Hg/ 3000 rpm ( 5 min limit ) - MATCH. Military Rated Power (Max. Combat in UK) : ALD-3F2 - 42 in Hg/ 3000 rpm ( 5 min limit ) vs RAF manual - 45.5 in Hg/ 3000 rpm ( 5 min limit ) - RAF limit HIGHER. Normal Rated Power (Max. Level/Climbing Continuous in UK) : ALD-3F2 - 37.2 in Hg/ 2600 rpm ( no time limit ) vs RAF manual - 38.5 in Hg/ 2600 rpm ( no time limit ) - RAF limit HIGHER. Maximum Cruising/Auto Lean (Max. Weak Continuous in UK) : ALD-3F2 - 28.2 in Hg/ 2280 rpm ( no time limit ) vs RAF manual - 30.5 in Hg/ 2300 rpm ( no time limit ) - RAF limit HIGHER. End of Story..... Allison engineers warning of the same conditions found in your combat report..... Allison abuse.pdf 1.82MB 0 downloads Of course they had to warn against use of such high Manifold pressure, it is pretty dangerous thing to do. As far as I'm concerned, it is like playing "Russian roulette". I am talking about 60 in Hg or more with V-1710-39 (- F3R). This picture is stupid, sorry. "Allison Time Bomb" is nickname from Lightning pilots flying in European Theater of Operations, nobody else used this nickname. Why is P-40 on this picture is a mystery to me, Allison engines in P-40s (well, at least from P-40D) were pretty reliable. 1
Crump Posted August 7, 2016 Posted August 7, 2016 And that's exactly what happened - first P-40Ns were equipped with standard automatic manifold pressure regulators ( aircraft 42-104429 through 42-106405, first P-40N-1CU through last P-40N-15CU), then Curtiss installed new automatic engine controls ( airplane 42-106406 and subsequent, first P-40N-20CU and subsequent ). Good to know but does not change the fact you cannot operate the V-1710F3R engine at 56"Hg without a MAP. Nor does it change the fact the USAAF did install MAP's on their P-40's when the aircraft came for service or depot level maintenance. Military Rated Power (Max. Combat in UK) : ALD-3F2 - 42 in Hg/ 3000 rpm ( 5 min limit ) vs RAF manual - 45.5 in Hg/ 3000 rpm ( 5 min limit ) - RAF limit HIGHER. The 45.5"Hg does not violate the 5 minute time limit set by Allison for 52"Hg.... The Type Certificate limitations are adhered too!! No issue or mystery involved. Normal Rated Power (Max. Level/Climbing Continuous in UK) : ALD-3F2 - 37.2 in Hg/ 2600 rpm ( no time limit ) vs RAF manual - 38.5 in Hg/ 2600 rpm ( no time limit ) - RAF limit HIGHER. This is kind of mystery but the difference is negligible. You are talking 1.3"Hg. That is well within the normal adjustment tolerances of the set screws!!! I tend to think it has do with the gauge error on the manifold pressure gauges used by the RAF. This may have something to do with units of measure. There was not a world standard for an inch until long after World War II despite several attempts to make one. Even more telling is the fact that the power produced at those settings agrees with Allison's limitations. Both list 1000hp as the Maximum continuous setting. It would be an aviation first and complete outlier for the RAF to violate convention on such a large scale contract. So whatever the gauge is saying, both the United States Manifold pressure gauge and rpm and the RAF manifold pressure gauge and rpm produce the same power.... That 1000hp adheres to the Type Certificate limitations! Maximum Cruising/Auto Lean (Max. Weak Continuous in UK) : ALD-3F2 - 28.2 in Hg/ 2280 rpm ( no time limit ) vs RAF manual - 30.5 in Hg/ 2300 rpm ( no time limit ) - RAF limit HIGHER. Who cares? This is not part of the Type Certificate that is mandatory. § 23.1521 Powerplant limitations. (a) General. The powerplant limitations prescribed in this section must be established so that they do not exceed the corresponding limits for which the engines or propellers are type certificated. In addition, other powerplant limitations used in determining compliance with this part must be established. (b) Takeoff operation. The powerplant takeoff operation must be limited by - (1) The maximum rotational speed (rpm); (2) The maximum allowable manifold pressure (for reciprocating engines); (3) The maximum allowable gas temperature (for turbine engines); (4) The time limit for the use of the power or thrust corresponding to the limitations established in paragraphs (b)(1) through (3) of this section; and (5) The maximum allowable cylinder head (as applicable), liquid coolant and oil temperatures. © Continuous operation. The continuous operation must be limited by - (1) The maximum rotational speed; (2) The maximum allowable manifold pressure (for reciprocating engines); (3) The maximum allowable gas temperature (for turbine engines); and (4) The maximum allowable cylinder head, oil, and liquid coolant temperatures. (d) Fuel grade or designation. The minimum fuel grade (for reciprocating engines), or fuel designation (for turbine engines), must be established so that it is not less than that required for the operation of the engines within the limitations in paragraphs (b) and © of this section. (e) Ambient temperature. For all airplanes except reciprocating engine-powered airplanes of 6,000 pounds or less maximum weight, ambient temperature limitations (including limitations for winterization installations if applicable) must be established as the maximum ambient atmospheric temperature at which compliance with the cooling provisions of §§ 23.1041 through 23.1047 is shown. https://www.law.cornell.edu/cfr/text/14/23.1521 It is only maximum continuous and any power level above that are set by the Type Certificate. Those are mandatory for everyone to follow in order for the engine to be airworthy. Walk into any airport pilot lounge and ask about best cruise practices and you will start a discussion. Even in aircraft as highly regulated as the Airlines, there are many techniques for best cruise practices. I see it every flight at work. So unless there is vibrational harmonics issue or some other technical reason that could lead to catastrophic failure..... Anything below Maximum Continuous is fair game to do what you want. Of course they had to warn against use of such high Manifold pressure, it is pretty dangerous thing to do. As far as I'm concerned, it is like playing "Russian roulette". I am talking about 60 in Hg or more with V-1710-39 (- F3R). Exactly. You do understand that you cannot sit a sea level and get 60"Hg or more out of an Allison V 1710F3R engine? You can only get that under certain atmospheric conditions of rammed flight with a load on the propeller. It is not a some whizbang turn of the screw adjustment and my P-40 turns into an F-22. It is you dove the aircraft under the right atmospheric conditions and instead of doing the right thing and pulling the throttle back....you left it alone or shoved it further open. We only hear from the survivors and those who won the lottery. This picture is stupid, sorry. "Allison Time Bomb" is nickname from Lightning pilots flying in European Theater of Operations, nobody else used this nickname. Why is P-40 on this picture is a mystery to me, Allison engines in P-40s (well, at least from P-40D) were pretty reliable. Certainly they were reliable when operated within their limitations. The Allison was a good engine and many aviators in World War II owe their life to it. I tend to think the reputation developed in part due to such practices as overboosting the engine when atmospheric and flight conditions permitted.
1CGS LukeFF Posted August 8, 2016 1CGS Posted August 8, 2016 (edited) Farky, thank you for your patience and the easy to understand and informative posts. +1 Farky, I hope you stay around here. Your way of explaining things is much appreciated. Edited August 8, 2016 by LukeFF
Vachik Posted August 8, 2016 Posted August 8, 2016 Welcome, guys! I'm from Russia. I do not know english, so I write through a translator. Excuse me. Russian virtual pilots concerned incorrect modeling aircraft P-40 in the game. And not only the engine. With FM as a problem. Aircraft in the game can not go to the required angle of attack wing. This makes it impossible to correct landing at three points. And also does not allow to make the right turn limit. Aircraft in the game does not have the required horizontal maneuverability. Motors Allison during the war were exploited beyond all limits. This is not your invention, it is not our invention. Everyone wanted to live. Therefore, pilots took off all engines and even a little bit.)) Write about this, our pilots who fought in the P-39 and P-40. Since the game can not be absolutely! P-40 is a legend. I'd like to have it right in the simulation game. Thank you for your work. "Crump" troll. We are also there.)) Good luck. 2
6./ZG26_Klaus_Mann Posted August 8, 2016 Author Posted August 8, 2016 Welcome, guys! I'm from Russia. I do not know english, so I write through a translator. Excuse me. Russian virtual pilots concerned incorrect modeling aircraft P-40 in the game. And not only the engine. With FM as a problem. Aircraft in the game can not go to the required angle of attack wing. This makes it impossible to correct landing at three points. And also does not allow to make the right turn limit. Aircraft in the game does not have the required horizontal maneuverability. Motors Allison during the war were exploited beyond all limits. This is not your invention, it is not our invention. Everyone wanted to live. Therefore, pilots took off all engines and even a little bit.)) Write about this, our pilots who fought in the P-39 and P-40. Since the game can not be absolutely! P-40 is a legend. I'd like to have it right in the simulation game. Thank you for your work. "Crump" troll. We are also there.)) Good luck. Well, Crump is the only one Providing Objective Sources against a Wall of Anecdotes. We are discussing how the Combat Effectiveness of the P-40 could be somewhat increased by showing that premissible Limits of the engines were higher than ingame right now, because the game is all about the permissible Limits. As it stands right now One side is claiming the Allison to be a Wonderweapon by Anecdote vs. Crump providing a pretty much unbiased Case towards higher Limits as they are right now, without getting all misty eyed. In this discussion I stand with Crump since he is the only one who has consistenly provided Evidence for his points. 2
Art Posted August 8, 2016 Posted August 8, 2016 (edited) Welcome, guys! I'm from Russia. I do not know english, so I write through a translator. Excuse me. Russian virtual pilots concerned incorrect modeling aircraft P-40 in the game. And not only the engine. With FM as a problem. Aircraft in the game can not go to the required angle of attack wing. This makes it impossible to correct landing at three points. And also does not allow to make the right turn limit. Aircraft in the game does not have the required horizontal maneuverability. Motors Allison during the war were exploited beyond all limits. This is not your invention, it is not our invention. Everyone wanted to live. Therefore, pilots took off all engines and even a little bit.)) Write about this, our pilots who fought in the P-39 and P-40. Since the game can not be absolutely! P-40 is a legend. I'd like to have it right in the simulation game. Thank you for your work. "Crump" troll. We are also there.)) Good luck. And what do you /or players from Russia think about Fw 190? In this game is unrealistic... Fw 190 A3 was better then Spit Vb but not here.. Answer me here thanks http://forum.il2sturmovik.com/topic/21732-whats-your-opinion-new-fw-fm/ Crump isnt troll how say Klaus he is one who has materilas many players just say and show nothing. Edited August 8, 2016 by Art
LLv24_Vilppi Posted August 8, 2016 Posted August 8, 2016 (edited) Well, Crump is the only one Providing Objective Sources against a Wall of Anecdotes. I think this is a fallacy. The claim is not against that the recommended engine limits are different from the documents (this would honestly be a silly argument). The claim is that the regulations were not always followed by the pilots and there indeed seems to exist historical documentation supporting this fact. What that historical evidence cannot provide us is quantifiable data. I.e. how long and how much abuse the engines could withstand in field conditions. What objective sources (or even anecdotes) has anyone provide to support the fact that rules and regulations were always strictly followed by everyone during missions in WWII? To be honest, I would even go so far as to say that this stand is not falsifiable at all and therefore moot. Sheer amount of attached documents does not mean that a person's claims are correct. Don't let that fool you. Read the actual documents and see what the people who wrote those reports are ACTUALLY saying, without any assumptions or extrapolating what they MIGHT be saying based on your own opinion. Edited August 8, 2016 by LLv24_Vilppi 1
Crump Posted August 8, 2016 Posted August 8, 2016 The claim is that the regulations were not always followed by the pilots and there indeed seems to exist historical documentation supporting this fact. Absolutely! The fact is pilots do not always follow the limitations and instructions. The NTSB has mounds of evidence to support that conclusion. The difference is some game players want to make an argument that not following the limitations is normal and a work around for a better performing aircraft. It is not. It is simply a great way to kill yourself in an airplane. That is why the Allison engineers wrote the memo warning about the practice of overboosting. It wasn't to encourage it or agree that the operating limits simply had to do with overhaul times. It was to say the limits were placed on the engine due to actual limitations in the motors structural strength. That is plainly stated in their memorandum. Overboosting was illegal in the fact that Allison would be absolved of all responsibility and could in fact legally have ended all technical support as well as warranties for the USAAF P-40's the moment they heard about it. They did not. Instead they took the time to educate the pilots and unit whom they heard about it. That says a lot about the importance of following the Operating Limitations and the extent to which they were followed. Allison had a real business out and could have canceled their contract forcing the US Government back to the negotiating table. Since it was the Government's fault, the Government would have still be responsible for PAYING Allison in full for that contract. It really says a lot about the character of Allison as a company, their patriotism, and their concern for our serviceman. The reality of violating Operating Limitations is the exact opposite some in this thread want to conclude. The vast majority of pilots follow the Limitations. They have a vested interest in their own survival and understand the limitations are due to hard physical constraints simply because the engineering margins required for flight are so small. I do not have a dog in this hunt. It is your game. If you want an "Arcade" version or you want a less realistic setting that allows you to overboost safely then by all means ask the Devs. I hope they give it to you and fully support it. To make an argument that overboosting is realistic and common practice in a discussion about history is simply not correct. It is just gaming biased. The claim is not against that the recommended engine limits are different from the documents (this would honestly be a silly argument). But that absolutely is the argument if you followed the thread. Read the actual documents and see what the people who wrote those reports are ACTUALLY saying, without any assumptions or extrapolating what they MIGHT be saying based on your own opinion. Do that please!!
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