ASh-82FN and its engine timer

[the_emperor]

I know I am kicking a dead horse regarding the engine limitations by strict timer but the 82FN engine does not seem the be so restricted. is seems to be able to run at WEP (boosted) for 10min+

while the manual states that no more than 5 minutes are allowed (sounding much more strict than the german and western allied engine limitations).

Is there an explanation why the game is much more generous regarding the engine Timer of that engine?

 

Cheers

 

[CountZero]

 

here it says 15min

[JtD]

There are several manuals for the engine, not surprising given it was used for decades. Time limits vary a lot.

 

Aircraft specfic for the La-5FN, the time limit for forzash varies between 5 (1943) and 15 (1944) minutes.

[CountZero]

15-5 = 10 ? or devs have some other document that shows 10min is used

[the_emperor]

The ones I have are from 1947 and 1954 and both specifically say no more than 5 minutes on WEP

[HR_Zunzun]

Maybe they are non war restrictions. More stricts than during the war.

[the_emperor]

26 minutes ago, HR_Zunzun said:

Maybe they are non war restrictions. More stricts than during the war.

 Could be. from what I gather the limitations on engines where not that strict on the russian side as long you keep the oil and water temperatures/pressures in check ?

maybe the overhault intervalls did not mater that much since combat survivability was not that high  since the probability that the plane was lost before the overhaul was high enough to take that risk?

[CountZero]

but how they come to limit of 10min, why not 15min like in manual from 1944, La-5FN is not tied to any DLC its collector airplane.

Im also now interested to know how they pick 10 min time for it.

 

Regarding real flying i highly doubt any pilot from any sides in war pay mutch atention to time limits of engines, if you had to use max power you used it for as long you have to, its either you get shoot down by enemy when you lower power after some abstract time in manual or you risk damaging engine... timers are just so important in game because they do blow your engine 100% of time when you go abow them.

 

If engine time limits were so strick that they 100% blow your engine after you go abow them, real airplanes would have alarm bell and countdow clock that warns pilots when timer will run out.

 

Limiting factors in using max power for pilots were, how mutch fuel ill waist by using it or how mutch will my engine overheat, or how mutch magic go-fast liquid i have not how many seconds or min i used it.

Edited September 5, 2021 by CountZero

[the_emperor]

 

It does also mention a hight limit of 1500-2000m

which is in agreement with what I have found so far. above that the engine seems to be set rated with to 2400rpm and 1000mm boost.

boost over 1000mm in the second supercharger seems to be forbidden

 

Edited September 5, 2021 by the_emperor

[CountZero]

i see in that 1944 manual on this page : 

Instruction for the pilot on the operation and piloting technique of the La-5 aircraft with the M-82FN engine ..., approved by the Air Force on 14 July 1943. 

 

So should be working same for 1943 La-5FNs if data in it is aproved in 1943 and prnted in 1944.

 

[the_emperor]

@CountZero Thank you very much.  By any chance, can you tell me the name of the manual or a picture of the front the page, so I may find it myself.

Many Thanks.

PS: yes, engine timers in the game are quite obscure. If it called emergency power, so you should be allowed to use it in an emergency and only have to keep the engine system in its limits (e.g. water/oil temperature and pressure) and watch your fuel gauge.

1 hour ago, CountZero said:

If engine time limits were so strick that they 100% blow your engine after you go abow them, real airplanes would have alarm bell and countdow clock that warns pilots when timer will run out.

If use risks the plane and pilot it should be banned permanetly, as the Germans did for their DB605A engine.

And after it was fixed the manuals do not mention any time limit, but in the game their is still an artificial 1min count down to destruction.

 

 

[CountZero]

I serched for one from video, that say 15min, found it here:

https://www.avsimrus.com/f/documents-16/lavochkin-la-5-fn-flight-manual--29518.html

[Cpt_Siddy]

2 hours ago, the_emperor said:

 

 

boost over 1000mm in the second supercharger seems to be forbidden

 

 

 

 

Have not stop me from using it. 

 

[LukeFF]

2 minutes ago, Cpt_Siddy said:

Have not stop me from using it. 

 

And it won't do you any good engaging it above 1000 m.

[Cpt_Siddy]

Just now, LukeFF said:

 

And it won't do you any good engaging it above 1000 m.

It makes plane release thicker black smoke, that scares the enemy and make it more orky. 

[1PL-Husar-1Esk]

Like to know more about this engine watch this, highly recommended.

 

 

Edited September 6, 2021 by 1PL-Husar-1Esk

[the_emperor]

Thank you all very much for your input.

Does any one else have access to documents regarding the La-5fn.

Thus far I have a pilot notes from 1944 (with 15min limitation), and two Engine Manuals from 1947 and 1954 (with 5 min limitation)

A 1944 english translation of the pilots notes (with 5min limitation) and a 1944 airframe/engine manual (with 5min limitations)

And a 1945 La-7 manual (with 10min)

but they all seem to be in agreement, that boost with 1200m and 2500rpm is limited to 1500-2000m hight. above that the engine seems to rated with 1000mm and 2400rpm.

Does any one else have documents mentioning the 10min limitations in the game or the 15min as the majority hints to a 5min limitation

Cheers

Edited September 6, 2021 by the_emperor

[gimpy117]

so they say to close all the cowl flaps. how long till you cook the thing? 

[Dakpilot]

4 hours ago, gimpy117 said:

so they say to close all the cowl flaps. how long till you cook the thing? 

 

Literally a couple of lines down it says keep CHT below 240 and oil temp below 85

 

Cheers, Dakpilot 

[JtD]

Typically, closing rads at top speed (which this chapter is about) is not a big issue for most of the aircraft of the era. The engine still gets sufficient cooling.

 

For some aircraft literally closing the cooling flaps was actually a difficult thing to achieve, since the air pressure at high speeds would ram them slightly open (flexible flaps, joints, rods, bearings and so on). Not to mention that gaps or intentionally left open bits would always allow some airflow. In practice, "closed" never really means "closed". It's just "least cooling".

[-=PHX=-SuperEtendard]

The closed position in the in game model:



Most of the opening is occupied by exhaust stacks but there are still gaps left for air to flow through.

And yeah the cowling has asymmetric bulges for the guns and now you can't unsee it either ?

Edited September 14, 2021 by -=PHX=-SuperEtendard

[the_emperor]

 

On 9/14/2021 at 9:30 AM, -=PHX=-SuperEtendard said:

And yeah the cowling has asymmetric bulges for the guns and now you can't unsee it either ?

Thank you very much, did not notice, now I cant unsee it XD

I found that even with oil radiator and exhaust shutters fully closed its nerly impossible to bring bring the FN engine to reach its temperature limits, even in steep climbs or long low speed manuevers at boost setting. Why was its cooling so effectiv?

[the_emperor]

Well,

I found a better scan of the comic style pilots notes regarding a 15min time limitation at WEP.

And it is quite obscure it reads more like 10min, but could be 15min (the "1" does look more like stroke than a "1" compared to others in the manual, shame that this number ist not that readable in this manual) and the the translation, and russian websites it is quoted as 5min:

http://wio.ru/yak3/rle-la5fn.htm  (here it is under 75. (d) so another manual might exist, still one need to get a original scan)

 

 

 

So to summarize:

3 sources  (´44, ´47, ´53) state a 5min limitation

1 source 10min (´44 but for the La-7 states 10min)

1 source is debatable (5,10,or15min)

Edited September 19, 2021 by the_emperor

[the_emperor]

I found another manual from 1943 stating 5min on WEP:

 

 

 

So to summarize:

4 sources  (´43´44, ´47, ´53) state a 5min limitation

1 source 10min (´44 but for the La-7 states 10min)

1 source is debatable (5,10,or15min)

Edited September 19, 2021 by the_emperor

[the_emperor]

The pilot notes for the Tu-2 with the Ash-82FN engine also state a 5min time limitation for that engine in boosted mode:

 

For better overview I have compiled here all primary sources stating the 5min WEP limit for the Shvetsov ASh-82FN engine and where I found them sorted from 1943 to 1954 (1943 La-5fn; 1944 La-5fn; 1945 Tu-2 Ash-82fn;1947 La-9 Ash-82fn; 1947 Ash-82fn; 1950 La-11 Ash-82fn; 1954 Ash-82fn).

 

 

Regarding the 10min time limit I have found thus far 1 credible source and one that seems questionable:

a) One source (1945) for the La-7 with M-82fn engine clearly stating 10min and

b) one source (1944) for the La-5fn that looks like it has been tempered with and a "5" was converted to a "10" (number longer centered between words as in other manuals) but it could also be a "15". 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

a)La-7

 

 

 

b) debateable La-5fn pilot notes

 

Edited March 27, 2023 by the_emperor

[Real_NBD]

It should also be noted that currently in-game the FN can run 2400 RPM and full boost for 20+ minutes without engine damage. This setup also provides the highest speed at low altitudes, giving the FN a massive advantage. The 10 minute limitation only applies at 2500 RPM.

Edited September 19, 2021 by SCG_NoBigDreams

[Cpt_Siddy]

Yeah and? It could do it in RL too.  There is ample documentation for that. 

Don't blame soviets for good engineering, blame the Germans for making such tight tolerances that nanosecond over timer-limit will cause Göering himself to strike your engine down! Same goes with the early Allisons engines we have on P-39 and P-40. 

 

Luckily, Americans came to their senses and corrected the manuals for P-38's, so the curse was lifted and the war won! If only Germans knew that printed word (in manuals) is mightier than top notch German engineering.

 

Edited September 20, 2021 by Cpt_Siddy

[the_emperor]

Yes, I assume that is the probleme here,

there is much documentation that the engines could be run far above the time (and in case of the P-39/40 boost) limitations especially in emergency combat situations, where you could not have your personal stop clock running, as long as the oil/water temperature/pressure limitations where in check.

But as of now the engine limitations in this game are slaved to the manuals.

[Giovanni_Giorgio]

1 hour ago, the_emperor said:

there is much documentation that the engines could be run far above the time (and in case of the P-39/40 boost) limitations especially in emergency combat situations, where you could not have your personal stop clock running, as long as the oil/water temperature/pressure limitations where in check.

 

There is an old Soviet joke that in regular times Pi=3.14..., but during a war and emergency situations it can be 4.

[Real_NBD]

4 hours ago, Cpt_Siddy said:

Yeah and? It could do it in RL too.  There is ample documentation for that. 

Don't blame soviets for good engineering, blame the Germans for making such tight tolerances that nanosecond over timer-limit will cause Göering himself to strike your engine down! Same goes with the early Allisons engines we have on P-39 and P-40. 

 

Luckily, Americans came to their senses and corrected the manuals for P-38's, so the curse was lifted and the war won! If only Germans knew that printed word (in manuals) is mightier than top notch German engineering.

 

I don't know where you get all your salt, why bring it here?

 

It's an issue because, as you mention, other fighters don't have such a benefit, P39, P47, P40 for example. And there is ample documentation that those aircraft could run their engines much harder than we can in the sim. It should be addressed. Not a big deal, but a thing that would improve QoL a lot for some players.

Edited September 20, 2021 by SCG_NoBigDreams

[Cpt_Siddy]

Check your sarcasm detector, its leaking. 

[CountZero]

On 9/19/2021 at 7:27 PM, the_emperor said:

I found another manual from 1943 stating 5min on WEP:

 

 

 

So to summarize:

4 sources  (´43´44, ´47, ´53) state a 5min limitation

1 source 10min (´44 but for the La-7 states 10min)

1 source is debatable (5,10,or15min)

Maybe we got La-7 ? 

I realy doubt you gona get any answer from devs on why its 10min, there is better chance of arcade engine timers get eliminated, then geting any info about this 5 or 10min debate.

 

Edited September 21, 2021 by CountZero

[the_emperor]

Well, to be honest I dont really expect an anwser or reaction, I was more curious whether some one does have any more information an that topic or other documents.

Maybe I shall move that topic to suggestions as of now the 5min timer limit seems reasonable according to the scources.

And getting an La-7 sometime would be sweet.