BF109 Engine Damage in boost/emergency mode

[StG2_Manfred]

....engines should work like they're factory fresh every sortie

 

IIRC it's exactly what devs said they were doing. No simulating of worn and torn machines, only factory fresh machines with no problems. It was asked in context of Russian planes having the standards of test machines (and without all the problems they came out of a factory then)..

 

So, if we have only factory new machines on one side, why we do not have them for the other side?

Edited January 5, 2018 by StG2_Manfred

[curiousGamblerr]

Well I think you're incorrect Fumes, and I think even the developers would disagree about the goals for this game, but I obviously can't speak for them.

 

Just because you can cite examples where encouraging realistic behavior is impossible without implementing terrible limitations (making planes break from unrealistic tactics) does not mean that doing so where it is possible (engines) is a bad idea.

 

Fortunately, your suggestion of removing engine limitations is never going to happen, so I don't really have to worry about it and we can agree to disagree.

[Talisman]

Folks,

 

Please see below for a link to AP 2095 Pilots Notes General (2nd ed 1943).  Makes interesting reading in terms of this thread topic.

 

This Air Publication, to be read as a 'companion to pilot notes', has an interesting reference to pilots notes in the introduction and 'limits'.  I realise that this is how the British managed things and is not related to the Bf109. 

It seems to me that the British allowed more pilot discretion with limits because there was a relatively large safety margin built in and any failures, in the main, were viewed as a possibility under 'extreme' circumstances only.  Limits seem more generally geared towards maintenance issues, rather than failures.

However, given that some aircraft designs, like the Bf 109, did not allow so much pilot discretion and limited engine usage by design function mechanical means (automatically turning off WEP after a minute or so, for example), could indicate that the stress margin's were a lot more critical and could not be left to chance or pilot discretion so much. 

 

http://spitfireforums.com/index.php?topic=361.msg1389#msg1389

 

Happy landings,

 

56RAF_Talisman

[Corsair]

However, given that some aircraft designs, like the Bf 109, did not allow so much pilot discretion and limited engine usage by design function mechanical means (automatically turning off WEP after a minute or so, for example), could indicate that the stress margin's were a lot more critical and could not be left to chance or pilot discretion so much. 

 

That is true for some Bf 109 variants, i.e as far as I understand, the 109 E and its DB 601 engines.

 

However as discussed in the other topic on the same forum (DB 605 A and 1,42 ata boost), after this boost ban was lifted, there was no clearly stated restriction (nor any mechanical limitation), consistent with a relaxed use, that shall be limited for maintenance purposes rather than in the fear of failures, as you rightly said. This and the fact that these engines were tested (sometimes destructively) way past beyond the 1 minute limit would imply that the engine is able to sustain the boost to such extent, and well within the needs of a pilot in a given flight. If limitations would occur, I believe they would be more caused by temperature issues that are dependent on very situational factors rather than the sheer mechanical inability of the engine to sustain it.

Edited January 5, 2018 by EC5/25_Corsair

[Talisman]

P.S.

 

Re my post above.  Worth noting at the top of page 26, that the engine limit figures provide a general guide only and that in combat and emergency other considerations may justify the pilot in disregarding these restrictions.

 

Again, this is for British aircraft/engines so not relative so much for other aircraft types, but are an interesting comparison if there are any documents from other countries air forces to compare with.

 

Happy landings,

 

56RAF_Talisman

[Venturi]

The main issue with using manual limits to determine what should, and should not be "dangerous", is that they are not necessarily bound to the actual limitations of the engines and fuel used.

 

...(Except insofar as these limits adhere to the actual physical limitations, either by luck or thoroughness of testing, on the part of those who drafted them. There is every indication that the Germans and British, having several years' worth of aerial warfare experience, were very much more in-tune with this, or honest, in their guidelines for operational use than the Americans. I defer on the Soviets...)

 

In this IL-2 world of the-letter-of-the-law-in-manuals-means-everything-to-engine-performance, those countries and engines which were less conservative in their manuals' written instructions, have the performance edge. When combined with the historical anecdotes, (which no-one should deny easily), it creates a logical quandary which, in the presence of a very simplified engine model (such as what IL-2 has), requires hard decisions to be made regarding how the engine limitations are manifested in the sim.

 

From an engineering and physics point-of-view, the hard-limit of any super or turbo-charged piston-engine's performance is always due to the physical limitations of detonation, imposed primarily by the octane rating of the fuel which was used. 

 

This is the reason why it is important to model detonation parameters - as they are paramount to solving all simulation issues related to in-flight failures of engines due to pilot abuse.

 

I believe the devs already understand this, and I hope that the online conversation will be constructive towards this end --- which would pretty much solve all issues extant.

 

And I quote, from a man who would know:

 

"Now the chief limitation (apart from mechanical ones) was detonation at high boost pressures." A.C. Lovesy, Rolls-Royce

Edited January 6, 2018 by Venturi

[=362nd_FS=RoflSeal]

Considering RAF pilot notes posted earlier talk about engine limits being ways to limit engine wear rather then hard limits, here is a relevant section from P-51D manual.

Edited January 22, 2018 by RoflSeal

[Talisman]

Considering RAF pilot notes posted earlier talk about engine limits being ways to limit engine wear rather then hard limits, here is a relevant section from P-51D manual.

 

Thanks for the post RoflSeal.  Interesting, as the engine used by the P51 was made by the British company Rolls Royce (or USA under licence) which provided engines to many other real life combat aircraft as well.  It would be nice if there was any documentary evidence of a similar or even a different approach by other countries.

 

Happy landings,

 

56RAF_Talisman

[Sgt_Joch]

well the key here is in the section that running at WEP for 1 hour is no worse than for 5 minutes "...provided engine temperatures and pressures are within limit.."

 

you could run these engines at full WEP for 8+ hours on a bench as long as engine temperatures was kept within limits or you could destroy it in minutes in an actual aircraft if fuel detonation occurred.

Edited January 22, 2018 by Sgt_Joch

[JtD]

Or you could run it for hours in an actual aircraft as long as engine temperatures and pressures were kept within limits.

[Sgt_Joch]

Or you could run it for hours in an actual aircraft as long as engine temperatures and pressures were kept within limits.

 

ok, I'll bite, show me one verifiable account of any pilot in ww2 running his Me109 F/G for hours at 1.42 ata.

 

just one will do. 

 

..and no, DCS does not count...

Edited January 22, 2018 by Sgt_Joch

[Panthera]

ok, I'll bite, show me one verifiable account of any pilot in ww2 running his Me109 F/G for hours at 1.42 ata.

 

just one will do. 

 

..and no, DCS does not count...

 

Why does it have to be a 109? Was the DB605 design so fundamentally different from a Merlin engine that it shouldn't have been able of sustaining its listed WEP setting for roughly as long?  Did the British/Americans use some sort of special bearing and radiator design not known to the Germans? Or did the Germans loose all of their machining tools so they had to use chisels instead?

 

I mean, come on

Edited January 22, 2018 by Panthera

[Dakpilot]

Merlins did not have to run on B4 fuel

 

Cheers Dakpilot

[Panthera]

Merlins did not have to run on B4 fuel

 

Cheers Dakpilot

 

Not an explanation as the limits were set based on maintaining roughly the same TBO. 

 

Furthermore it's a bit too easy to simply say "find German reports saying they ran for hours at WEP like we have for the Allies" when 99.9% of German AAR's are lost.  

[Dakpilot]

Do some research on the engines and fuel and getting reliable power from low octane without detonation, Merlin and DB were designed from very different poles as far as getting HP from an engine

 

DB 605 was not a reliable/good engine, overbore of already at end of limit/highly stressed high compression DB601 when at high boost on B4 late DB605's were not lasting 20 hrs and reliability suffered because of this operating at close to design limits

 

Cheers, Dakpilot

[Venturi]

Or you could run it for hours in an actual aircraft as long as engine temperatures and pressures were kept within limits.

 

As long as detonation did not occur, which depended primarily on the proximity of the manifold pressure to the instantaneous detonation point... the instantaneous detonation point in turn depending on the fuel octane...

 

I agree completely that as long as the detonation point wasn't reached, the primary issue would be random engine parts failure (which we don't really have modeled in the sim)...

[Venturi]

Do some research on the engines and fuel and getting reliable power from low octane without detonation, Merlin and DB were designed from very different poles as far as getting HP from an engine

 

Completely agree

 

DB 605 was not a reliable/good engine, overbore of already at end of limit/highly stressed high compression DB601 when at high boost on B4 late DB605's were not lasting 20 hrs and reliability suffered because of this operating at close to design limits

 

It was a good engine provided one understands that compromises were made to increase power as much as possible given the limitations that strategic considerations imposed. Such as: overall manufacturing costs (no multi-stage s/c), and absolute manifold pressure limits (low fuel octane). The engine's long block did not appreciably weigh more than a Db601, yet provided more power and more displacement while still running on fuel which was 87 octane, while the allies used up to (effectively) 150octane fuel for their end-of-war Merlins, Allisons, and R2800s.

[Panthera]

Do some research on the engines and fuel and getting reliable power from low octane without detonation, Merlin and DB were designed from very different poles as far as getting HP from an engine

 

DB 605 was not a reliable/good engine, overbore of already at end of limit/highly stressed high compression DB601 when at high boost on B4 late DB605's were not lasting 20 hrs and reliability suffered because of this operating at close to design limits

 

Cheers, Dakpilot

 

You're placing way too much merit on a couple of qoutes posted regarding late war TBO, the explanation for which can be directly placed on the general lack of spare parts & lubricants suffered by the German armed forces late in the war (something which had a huge impact on the reliability of ALL German motor vehicles), and not with any faults in the design of the engine itself. This is made pretty clear when we look at the same engines operated years earlier or by the Finnish. 

[Venturi]

To get an illustration of how important a bottleneck fuel was, just utilizing the Eastern front as an example...

 

The FW190 was not utilized on the eastern front much in 1942-43 because the BMW 801D required C3 fuel (100oct) to run. This fuel was in shorter supply and given the logistical problems the German supply train faced in its far-flung advances into the USSR, it certainly made more sense to use the Bf109, which ran on the far more common B4 fuel.

 

Fuel availability and importance... just one of the things that goes into war time decision making. 

 

Here is one blogger's excellent expose of the issue during the Battle of Britain: http://thedaysofglory2.blogspot.com/2010/08/aviation-fuel.html

 

"Hardly marked down as a "war-winner" and rarely given an airing, improvements in aviation fuel technology played a vital part in the Battle of Britain, providing timely increments to the power of engines and the speed of such aircraft as the Spitfire and Hurricane.

In fact, even prior to the outbreak of war, the technology of fuel for the internal combustion engine was advancing. It has gone though rapid development in the 20s and 30s when motor fuel had been of variable quality, and aviation fuel little better. 

The search was on for fuel which would solve the problem of detonation in the cylinder, where the air-fuel mixture does not burn in a controlled fashion when ignited by the spark plug. Instead, it explodes prematurely as a result of heat and pressure, known as "knocking". 

In high performance engines, this could cause considerable damage to piston and bearings. It thus became essential to find a way of operating an engine so it would not suffer detonation, to prevent power output being limited by fuel performance.

All aircraft engines of the Battle of Britain era were mechanically-supercharged internal combustion engines. The supercharger used engine power to compress intake air to feed to the cylinders. The centrifugal compressor had a fixed compression ratio at any given rpm. Let's take the 1940 R-R Merlin III as an example. This engine had a maximum power of 1030HP at 16.250 feet, using 6.25lbs boost*. 

This implies a compression ratio of around 2.7. (manifold pressure 20.95 psi, atmospheric pressure at 16250 ft, 7.86 psi.) The supercharger takes 100hp or so at 3000rpm engine speed, whether the power is being used or not.

You can only use all the boost at 16,250ft. Below that height you are compressing the air but must run the engine throttled to avoid exceeding the boost limit. 16250ft in this case is the full throttle height. This is the case when using the 87 octane fuel available to both the RAF and the Luftwaffe.

In the spring of 1940 supplies of 100 octane fuel from the USA became available to the RAF. This made it possible to run the Merlin at a higher boost pressure without detonation. Limited by the greater detonation resistance of 100 octane fuel and by the mechanical strength of the Merlin itself, a new boost limit of +12lbs was imposed, for use in emergency with a time limit of five minutes. 

No change to the engine itself was required, just a new gated position on the throttle and a change to documentation. The increased boost gave an extra 300 horsepower, a 30% increase, up to a new full throttle height of around 9000ft where the compressor's ratio delivered the +12lbs. 

A combat for an RAF fighter would typically involve a scramble takeoff and a formation climb directed by the ground-based controller, who would try to put the formation in a position to intercept a raid. 

If successful there would be an engagement at the height of the incoming bombers, which would be above the heights where the 100 octane performance boost took place. Inevitably, fighter combat tends to be downhill, as any intensive manoeuvring uses up energy faster than the engine can provide it. 

The RAF fighter pilot might find himself chasing, or being chased by, a 109 downwards into the area where he had the advantage of 100 octane. The effect of the extra 300hp was to give the Spitfire pilot a clear performance advantage over the 109 in every way, speed, climb and ability to sustain a turn.

The pilot of a Hurricane would find his position improved from being at a marked disadvantage to something approaching parity. The availability of 100 octane fuel meant a significant increase in effectiveness and survivability for RAF aircraft.

The Luftwaffe had limited quantities of 96 octane fuel for new marks of Me 109s only in the later stages of the battle. Their engines were of larger capacity, more lightly loaded and with less aggressive supercharger output. The normal Me 109E operated with a boost equivalent to +5. Only in 1944 were pressures equivalent to +12 allowed in the later 109s. The RAF ended the war using +25 boost and 150 Octane fuel in the later Spitfires, giving twice the power of a 1940 Merlin with the same rpm and capacity.

* British engines measured their manifold pressure in pounds of boost. Sea level ambient pressure is zero pounds boost, or a pressure of 14.7 psi. So the actual manifold pressure at +6.25 lbs boost is 14.7 + 6.25 = 20.95 psi."

[Dakpilot]

You're placing way too much merit on a couple of qoutes posted regarding late war TBO, the explanation for which can be directly placed on the general lack of spare parts & lubricants suffered by the German armed forces late in the war (something which had a huge impact on the reliability of ALL German motor vehicles), and not with any faults in the design of the engine itself. This is made pretty clear when we look at the same engines operated years earlier or by the Finnish. 

 

 

It is possible that I am not just relying on a couple of posts regarding late war TBO

 

read up on history of DB605, and the difficulties that it suffered in trying to get that HP out of basically an overbored 601 on low octane fuel

 

I am not slagging off the engine or German engineering but there were realities. run a mid/late war Merlin on 87 octane at high boost and see what would happen

 

same as happened with Allison in P-39 on Russian fuel, was restricted to 40" and 45" WEP for very short time or it threw a rod due to detonation complications, fact, and well documented

 

Cheers, Dakpilot

[Venturi]

The question is, is the Russian front availability of fuel modeled...

I believe they got quite a lot of USA 100/130 avgas via lend lease... ?

[=362nd_FS=RoflSeal]

 

 

no multi-stage s/c

The fluid coupling supercharger used on DB engines effectively didn't require multiple gears like a friction coupled supercharger,

Edited January 22, 2018 by RoflSeal

[Venturi]

multi stage

[Dakpilot]

The question is, is the Russian front availability of fuel modeled...

I believe they got quite a lot of USA 100/130 avgas via lend lease... ?

 

Currently I (assume ) that the P-40 and Spit are modelled on western fuel (they would have to be?)

 

but there are tons of pilot reports on having to use russian fuel, (P-40/P-39/Spitfire) some pilots never even flew on high octane western in their whole wartime career, and at end of war and later, PVO Spit IX squadrons were reported using only Russian fuel

 

There was a lot supplied but probably only to frontline Guards units and such, it appeared to be in short supply from what I have read..but who knows

 

anyway drifting off topic

 

Cheers, Dakpilot

[Venturi]

http://www.whatreallyhappened.com/WRHARTICLES/pearl/www.geocities.com/Pentagon/6315/lend.html

 

This is a good document to understand the sheer breadth and quantity of lend-lease materials supplied to the USSR by the western Allies....

 

" of note is the 558,766 gals. of "Ethyl Fluid". IF this is the Tetraethyl lead for aviation fuel it is a substantial boost for the Russians. Since it is used at about 1cc per 1000cc of fuel. (3-4 cc per US gallon or about 1cc per liter. Again, IF, this was Tetraethyl lead it was enough for around 6.6 million tons of Av gas. The Russians may well have been able to produce small quantities of Tetraethyl lead on their own, but without enough of it you can forget 95 octane gas in ant quantity. The Russians would have been using 70-80 octane gas."

Yes, getting OT.

[Panthera]

It is possible that I am not just relying on a couple of posts regarding late war TBO

 

read up on history of DB605, and the difficulties that it suffered in trying to get that HP out of basically an overbored 601 on low octane fuel

 

I am not slagging off the engine or German engineering but there were realities. run a mid/late war Merlin on 87 octane at high boost and see what would happen

 

same as happened with Allison in P-39 on Russian fuel, was restricted to 40" and 45" WEP for very short time or it threw a rod due to detonation complications, fact, and well documented

 

Cheers, Dakpilot

 

Why not rely on actual specified TBO's?  The DB605 was listed with a ~200 hour TBO in mid 1943 as tested by Rechlin (not Mercedes), only to fall to ~30-50 hours in late 44 to 45 as pr. pilot accounts. Was it a coincidence that operational availability amongst German army motor vehicles as a whole dropped by a similar amount in the same timeframe? I don't think so.

 

As a lack of spare parts & lubricants started to mount it's effects were felt across all branches of the German armed forces, and esp. with the airforce and panzers. As a result German engines had to go much longer in between maintainance stops & oil changes as compared with their Allied counterparts, which inevitably will lead to a shorter TBO.

 

Before this period of shortages however the DB605 running on B4 was listed as having pretty much the same TBO as the Merlin engine running on 100 octane fuel.

Edited January 22, 2018 by Panthera

[Venturi]

Currently I (assume ) that the P-40 and Spit are modelled on western fuel (they would have to be?) If so their detonation limits would be according to 100/130 oct fuel (yes, they would have to be).

 

but there are tons of pilot reports on having to use russian fuel, (P-40/P-39/Spitfire) some pilots never even flew on high octane western in their whole wartime career, and at end of war and later, PVO Spit IX squadrons were reported using only Russian fuel

 

There was a lot supplied but probably only to frontline Guards units and such, it appeared to be in short supply from what I have read..but who knows

 

Good info thanks,

 

anyway drifting off topic

 

Why not rely on actual specified TBO's?  The DB605 was listed with a ~200 hour TBO in mid 1943 as tested by Rechlin (not Mercedes), only to fall to ~30-50 hours in late 44 to 45 as pr. pilot accounts. Was it a coincidence that operational availability amongst German army motor vehicles as a whole dropped by a similar amount in the same timeframe? I don't think so.

 

The point being that 1.42 is very close indeed to detonation parameters of B4 fuel, and that prolonged operation would induce detonation... thus the burnt-through piston tops and ruined main bearings.

Certainly further late war complications due to strategic shortages aggravate such issues. But there is a reason nearly all Luftwaffe aircraft operate at a maximum of around 1.4ata.

[Dakpilot]

Why not rely on actual specified TBO's?  The DB605 was listed with a ~200 hour TBO in mid 1943 as tested by Rechlin (not Mercedes), only to fall to ~30-50 hours in late 44 to 45 as pr. pilot accounts. Was it a coincidence that operational availability amongst German army motor vehicles as a whole dropped by a similar amount in the same timeframe? I don't think so.

 

Go back to post #172 and consider the answers to your question

 

In mid 43 the DB 605 was fully banned from 1.42 ATA

 

Cheers, Dakpilot

[Venturi]

http://kurfurst.org/Engine/Boostclearances/DB605_142ban_June1942.html

 

 

 

Technical Sheet issued by

the Quartermaster General

(Air Equipment)

Berlin, 18th June 1942.

Subject:      DB 605 engine in the Me 109 G.

 

                A number of cases of breakdown in the DB 605 engine as 
a result of pistons burning through occured. The following must be therefore observed.

                The take-off and emergency output with a boost pressure of 1.42 atm. and 2800 revs. may not at present be used. The climbing and combat output with 1.3 atm. and 2600 revs. may, in the case of the older engines (for works numbers see below), be used when operationally essential.

 

                If, in spite of these regulations, a piston does burn through, this is indicated by a strong regular vibration of the engine.
It is still possible to reach the nearest friendly base if the stress is immidiately reduced to about 1600 revs. and the lowest possible boost pressure. The vibration of the engine as a result of piston damage
remains unchanged when both magneto 1 and magneto 2 are switched on, so
that it is possible to confuse it with the a damaged sparking plug. On
the bench, bursts of blue vapour are emitted from the housing ventillator
when a piston is damaged.

                In engines with reinforced pistons the danger of their
burning through is not so great as in the older version of the piston, but the take-off and emergency output may still not be used. The following engines are fitted with reinforced pistong headsÉ

                Works numbers 25796, 35706 and 77731 and upwards. Also
the engines with the following works numbers:

 

               The pistons of older engines (before above-mentioned works
numbers) will be replaced by reinforced pistons during the first partial overhaul.

               Older engines mst be partially overhauled after 50 hours,
engines with reinforced pistons after 100 hours.

               Partial overhauls of the DB 605 are at present carried out only by the industry (home or front-line repair works).

               To prevent damage due to overheating of the ignition harness, the engines are at present being fitted with bakelite plugs and the engine cowlings with sparking plug ventilators. (Modifications to be carried out by troops in the case of aircraft already supplied). 

               Teleprinter message R.L.M. GL/C-TT No.1374/42 of 12.6.42 is hereby cancelled.

Edited January 22, 2018 by Venturi

[Panthera]

Go back to post #172 and consider the answers to your question

 

In mid 43 the DB 605 was fully banned from 1.42 ATA

 

Cheers, Dakpilot

 

Due to an oil cooling issue.

 

Once this issue was resolved the ban was lifted and no time limit is ever mentioned.

[Venturi]

I think if you read the above document, a different story as to why this limitation was put in place becomes apparent.

Pistons do not "burn through" unless there is detonation present.

[=362nd_FS=RoflSeal]

multi stage

 Multi geared, multi stage

How they work generally is the second stage impellor is geared directly off the crankshaft. The first stage impellor like on Merlin has 2 gears, one that requires less power to drive it and is optimized for low altitude, and other requiring more power to drive and obviously optimized for high gears.

Some aircraft like the Corsair had 3 gears, 2 stages, 3rd gear being neutral, completely disconnecting the first stage impellor from the crankshaft.

http://www.dtic.mil/dtic/tr/fulltext/u2/a801158.pdf

http://www.wwiiaircraftperformance.org/Aircraft_Engines_of_the_World_Rolls-Royce_Merlin.pdf

 

 

 

 

 

 

Fluid coupled superchargers allow supercharger speed to vary and not be slaved to the speed of the crankshaft. At full throttle height, supercharger is effectively  the same as friction locked to the crankshaft gearing ratio, as altitude decreases, the fluid coupling allows the supercharger to slow down independent of the gearing ratio, keeping the required manifold pressure required without any "deadzones" where one gear has reached it's full throttle height and the higher gear still doesn't produce as much power

[Panthera]

I think if you read the above document, a different story as to why this limitation was put in place becomes apparent.

Pistons do not "burn through" unless there is detonation present.

 

By august 43 the ban was no longer present however, the problem having been solved via the addition of new piston heads and oil centrifuge mentioned in the reports concerning the ban, and possibly re-timing of the ignition. A TBO of 200 hours is subsequently listed for the DB605A-1 cleared for 1.42ata.

[ACG_Smokejumper]

Realisim in behavior is not a thing. Pilots in game should receive as realistic as possible an aircraft and then let them decide how to fly it. Behavior is subjective. Physics isn't.

 

 

 

I actually agree with most of what you are saying so go easy bud.

 

Okay here goes.... I like your idea of removing time limits for the reals however, if we do that we should go full real and have random engine fire/failures etc, etc, etc.

 

I feel there is a compromise to be made here. Extend the time to say 10 minutes and every minute after this your chance of an engine failure rises exponentially. I like your evidence including your anecdotal but one we are missing is the guys who never came back over a random engine failure.

 

A compromise between full real and for the sake of the "game" needs to be made. At the end of the day this is a game. Even DCS doesn't go full real with random engine fires killing the pilot. One of the anecdots I've read again and again is that warbirds like to catch on fire for just about no reason.... All of them.

[LColony_Kong]

I actually agree with most of what you are saying so go easy bud.

 

Okay here goes.... I like your idea of removing time limits for the reals however, if we do that we should go full real and have random engine fire/failures etc, etc, etc.

 

I feel there is a compromise to be made here. Extend the time to say 10 minutes and every minute after this your chance of an engine failure rises exponentially. I like your evidence including your anecdotal but one we are missing is the guys who never came back over a random engine failure.

 

A compromise between full real and for the sake of the "game" needs to be made. At the end of the day this is a game. Even DCS doesn't go full real with random engine fires killing the pilot. One of the anecdots I've read again and again is that warbirds like to catch on fire for just about no reason.... All of them.

Quite the opposite actually, regarding the concept of full real and what has to happen. Im glad we agree on the rest. 

 

Removing the engine limits does not logically infer that we need to add random engine failures. What should be modeled, only, is a a simulation of a functional pristine airplane. Which is what the developers have stated is their intended goal. 

 

Adding any sort of reliability mechanic is complete nonsense because it will always be an inconsistent abstraction, unless the failure is specifically due to pilot error, like too high RPM with mismatched prop pitch. Mechanical failures that are not the result of exceeding design limits do not happen randomly. They happen due to measurement errors, mechanic errors, factory errors, etc. These are all things that are out of the players control and cannot be managed for. 

 

Nobody in a game wants their airplane to randomly fail due to no fault of their own. This would not be any fun, and would almost certainly be abstracted poorly. So yes, there must be compromises for game reasons. And that compromise is this: The only thing a simulator can simulate halfway decently is the physics of a functional example of the airplane in question. This is why in tank simulators we don't have Panthers whose final drives bust all the time. Etc. Adding abstractions like the current engine damage model only serve to ruin what simulation was already in place while adding nothing of actual simulation value. 

 

 

 

Engines do not explicitly fail from running the engine at authorized emergency settings for longer than the manual states. If a functional engine fails while at high power, it is not because the high power worn the engine down in 1-5min and the engine just imploded. It is a matter of absolute fact that broadly speaking no nation/designer authorized official boost settings that placed the engine so close to mechanical failure that it was imminent within a matter of minutes.  Such a rating would have been absurd even in conception since it would have been splitting hairs with regards to any sort of safe operation. 

 

 

The premise of the contrary position in these two threads is absurd. The time limits in aircraft manuals have nothing to do with preventing the sudden engine destruction we have this game. There is therefore NO REASON to defend the mechanic on these grounds. But for some ridiculous reason we have people still trying to defend these time limits as somehow being relevant to immediate engine failure. 

 

The fact of the matter is that one side in this conversation is justifying a completely made up failure condition based on time limits in manuals which were not talking about such a thing.  

 

In other words, these times are being used to support a failure type that they are not evidence for.

 

And despite the fact that all the relevant data shows that we should be allowed to run these engines for as long as we like, we are still a having this silly debate because the coconut effect must be defended etc. 

Edited January 23, 2018 by Fumes

[Dakpilot]

Quite the opposite actually, regarding the concept of full real and what has to happen. Im glad we agree on the rest. 

 

 

 

And despite the fact that all the relevant data shows that we should be allowed to run these engines for as long as we like, we are still a having this silly debate because the coconut effect must be defended etc. 

 

You are advocating having a 1941 P-40E-1 producing 1750hp indefinitely

 

something a late 1944 DB605 AM could barely do...

 

good luck with that 

 

you clearly seem to have a lack of understanding how aero engines work and history

 

Cheers, Dakpilot

[LColony_Kong]

You are advocating having a 1941 P-40E-1 producing 1750hp indefinitely

 

something a late 1944 DB605 AM could barely do...

 

good luck with that 

 

you clearly seem to have a lack of understanding how aero engines work and history

 

Cheers, Dakpilot

Im not the one demonstrating ignorance here, but you keep on defending your coconut effect. 

 

"Cheers" Fumes. 

[LColony_Kong]

 

Just in case it didnt sink in the first time. 

Edited January 23, 2018 by Fumes

[Panthera]

Should also be noted that the TBO of the V-1650 engine was a similar 200 hours during WW2.  The V-1710 also featured a similar TBO, but it went as low as 50 hours in Russian service.

Edited January 23, 2018 by Panthera

[ZachariasX]

 

 

multi stage

Mind the intercooler.