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Indeed very useful information, thanks!

Personally, I stopped having engine thrust issues on 2nd/3rd take-off within the same mission, once I started paying close attention to the R/J limits :)

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Indeed very useful information, thanks!

Personally, I stopped having engine thrust issues on 2nd/3rd take-off within the same mission, once I started paying close attention to the R/J limits :)

 

Yes! staying within the limits, I have no problem with multiple flights

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Hi guys, I'm still reviewing code for issues with the over limit logic, however keep in mind that the manual explicitly states that there are limits which must be pilot maintained even with the DECU in full operation and JPT limiter on and all that. I think someone has repeatedly posted the limits table, the notes below it state what limit states require pilot attention.

 

In addition the stuff currently not modeled won't have much bearing on the DECU logic as that was the first thing implemented, the failure modes (MFS, P3/Fuel Flow limited behavior, JPT off, DECU off) won't have much affect on this.

 

And....Mic drop :thumbup:

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I’ve had the time to do a little more testing on the “subtle” engine performance degradation that is currently modeled. As it is now, the engine is scripted to destroy itself exactly at all the time limits in the aircraft limitations chart.

 

 

Just a few examples:

Combat 111% - JPT well below limits and even below MCT JPT - and at exactly 10 minutes - JPT spikes - I’ve seen it spike as high as 997. Even at these extreme temps, engine would run indefinitely at 111%. Of course though, thrust is massively reduced to the point of a normal landing is probably not possible.

 

Max Thrust 109% - same deal - at 15 minutes - JPT spikes. Did not move throttle from max and this one eventually gave me a fire light, but engine continued to run the entire time.

 

Short Lift Dry 113.5% - have to check this one again - it lasted 3 minutes - must’ve mis scripted this one - book limitation is 15 sec.

 

I’m sort of curious what failure mode we are simulating here anyway? A fuel control runaway leading to JPT spike? I just can’t figure out what would cause the JPT to spike like that.

 

Anyway, the point of this is I know you virtual pilots are giddy about being able to break your engine. It proves how good of pilots you are because “I’m not having that problem, you must not be watching your JPT!”.

 

But all of this scripted engine damage is far from realistic and is certainly not how a turbine engine would respond in a real time limit exceedance.

 

Unless you have a Harrier pilot on staff that has a real world example of ole “Wash Out” burning in after foolishly operating 11 minutes at combat power, I believe this JPT spike is over done, and unrealistic.

 

I contend the engineers know at what temp the metal will be damaged and what RPM the engine can no longer sustain without shedding parts. They then add a safety margin. Then they design a electronic controller to protect the engine from reaching the safety margin. There, done, engine safe.

 

However extended high power settings and high temps cause the engine to wear at a faster rate. Turbine blades erode and fans creep. But this is “subtle” and takes hundreds of hours. It doesn’t happen in 10 minutes!

 

To extend the time of service of a engine additional “timed” limitations are added. Exceeding these limits does not damage the engine. It just wears it quicker. All of this is tracked by the mx computer and can be downloaded by the operator. There is even a Engine life units number on the engine page in this aircraft. During peacetime training these limits are carefully maintained to keep costs low for the operator. However - in combat - which is what we are simulating, if I need to take some life away from the engine to preserve the aircraft, damn right that throttle isn’t coming back at 10 minutes. I don’t care if they have to do a engine swap, it's better than a burning hole.

 

I have carefully flown this aircraft, with the engine chart limitation chart printed out and still had problems doing a subsequent STOL takeoff. Engine was fine at 116% wet, suddenly JPT spiked and thrust was lost and I crashed. Has happened more than once. I know I didn’t hit any of the scripted timed limits. I’ve also got into a fresh jet, and the OT light is already flashing, and it just seems like its not making power. I’ve had problems after refueling and rearming, subsequent STO leads to overtemp and crash. All of this is frustrating, mostly because I know it is “gamed up” and not how a real jet would respond.

 

I just want to point this all out before these artificial scripted time limits get “locked” in and we add engine management complexity to a aircraft that really doesn’t have a lot of complexity. That is the beauty of a jet turbine. It just keeps on running.

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I told myself I wasn't going to ready this entire thread, 4 pages in I just said well might as well keep going.

 

My two cents for what it's worth, Razbam has done a fantastic job in implementing engine wear and tear with respect to limitations. DCS modules have been lacking this system for quite some time(minus the warbirds for the most part) Now the "rate" of wear and tear is probably a different discussion and extremely variable from meterogolical conditions, to different engines made at different assembly plants or whatever. The point is no two engines are exactly the same, so measuring rate of wear and tear is highly subjective and is why all engines have timetables of when their inspections are required.

 

Players are not used to being "respectful" to their engine management use. So naturally what do we do? Make forum posts saying it must be a bug must be a bug. Well in this case I actually think not. Like others have stated in this thread I have successfully made numerous sorties 6-7 at a time with absolutely zero problem. I think proper procedure for coming into a vertical landing is very easily misunderstood and performed by the majority incorrectly. Expecting to have the outright engine power to just climb out of a nasty sink rate or improper approach. They shove the throttle up damage the engine and say the aircraft is bugged.

 

Brings me back to the original m2000 days when F15/Su33 players said the mirage FM was bugged because they were being out turned and out "knifed" in the merge.

 

Pay close attention to your power management, just because the limit is "780" or whatever it may be at that scenario, don't run at "780" and this bird will get you home just fine. Our entire squad has had absolutely zero problems with power *when* treating the aircraft properly.

 

Great job and thank you RAZBAM! Keep up the good work.

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Brings me back to the original m2000 days when F15/Su33 players said the mirage FM was bugged because they were being out turned and out "knifed" in the merge

 

If you think the Mirage flight model isn't,t bugged, then you have no clue about simple aerodynamics. The Mirage flight model at low speed and high alpha is completely goosed and unrealistic. Whilst a great module I have given up flying it, as I got sick of being unable to recover the AC as it would not increase speed with max AB whilst slow and low.

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I’ve had the time to do a little more testing on the “subtle” engine performance degradation that is currently modeled. As it is now, the engine is scripted to destroy itself exactly at all the time limits in the aircraft limitations chart.

 

 

Just a few examples:

Combat 111% - JPT well below limits and even below MCT JPT - and at exactly 10 minutes - JPT spikes - I’ve seen it spike as high as 997. Even at these extreme temps, engine would run indefinitely at 111%. Of course though, thrust is massively reduced to the point of a normal landing is probably not possible.

 

Max Thrust 109% - same deal - at 15 minutes - JPT spikes. Did not move throttle from max and this one eventually gave me a fire light, but engine continued to run the entire time.

 

Short Lift Dry 113.5% - have to check this one again - it lasted 3 minutes - must’ve mis scripted this one - book limitation is 15 sec.

 

I’m sort of curious what failure mode we are simulating here anyway? A fuel control runaway leading to JPT spike? I just can’t figure out what would cause the JPT to spike like that.

 

Anyway, the point of this is I know you virtual pilots are giddy about being able to break your engine. It proves how good of pilots you are because “I’m not having that problem, you must not be watching your JPT!”.

 

But all of this scripted engine damage is far from realistic and is certainly not how a turbine engine would respond in a real time limit exceedance.

 

Unless you have a Harrier pilot on staff that has a real world example of ole “Wash Out” burning in after foolishly operating 11 minutes at combat power, I believe this JPT spike is over done, and unrealistic.

 

I contend the engineers know at what temp the metal will be damaged and what RPM the engine can no longer sustain without shedding parts. They then add a safety margin. Then they design a electronic controller to protect the engine from reaching the safety margin. There, done, engine safe.

 

However extended high power settings and high temps cause the engine to wear at a faster rate. Turbine blades erode and fans creep. But this is “subtle” and takes hundreds of hours. It doesn’t happen in 10 minutes!

 

To extend the time of service of a engine additional “timed” limitations are added. Exceeding these limits does not damage the engine. It just wears it quicker. All of this is tracked by the mx computer and can be downloaded by the operator. There is even a Engine life units number on the engine page in this aircraft. During peacetime training these limits are carefully maintained to keep costs low for the operator. However - in combat - which is what we are simulating, if I need to take some life away from the engine to preserve the aircraft, damn right that throttle isn’t coming back at 10 minutes. I don’t care if they have to do a engine swap, it's better than a burning hole.

 

I have carefully flown this aircraft, with the engine chart limitation chart printed out and still had problems doing a subsequent STOL takeoff. Engine was fine at 116% wet, suddenly JPT spiked and thrust was lost and I crashed. Has happened more than once. I know I didn’t hit any of the scripted timed limits. I’ve also got into a fresh jet, and the OT light is already flashing, and it just seems like its not making power. I’ve had problems after refueling and rearming, subsequent STO leads to overtemp and crash. All of this is frustrating, mostly because I know it is “gamed up” and not how a real jet would respond.

 

I just want to point this all out before these artificial scripted time limits get “locked” in and we add engine management complexity to a aircraft that really doesn’t have a lot of complexity. That is the beauty of a jet turbine. It just keeps on running.

 

 

This, +1. The helicopter I fly in real life (CH146 Griffon) has many, many limits that are very easy to exceed. The vast majority of them exist for extended life cycle only, and in emergency or combat situations the aircraft has far more to give before reaching failure. I know people who have saved their aircraft and crew by vastly exceeding the limits; the aircraft did not fail or fall out of the sky. Of course, upon return the aircraft must undergo extensive inspections and maintenance action, including the reduction of the life length of many components and often a rebuild or replacement of affected components. However, exceeding limits does not result in an instant breaking of the airplane until you are vastly exceeding the limit or doing so for a lengthy time.

 

I realize we are not simulating the same aircraft here, but the philosophy has been the same in every aircraft I have ever flown, fixed wing or rotary wing.

 

If I’m in the middle of a dogfight, I’m going to use combat power - and I’m going to hold it longer than 10mins if it means losing the fight. The engine should not, and would not, catastrophically fail. However, when I got home from that fight, I’d hand the keys to maintenance and say sorry guys, broke that one... if I botch a hover landing and need to punch it to get myself back into a safe regime of flight, I have no doubt the aircraft would do it, I would just be required to land and hand that plane to maintenance as soon as possible. We exceed limits all the time, sometimes accidentally and sometimes intentionally to save the aircraft and crew. It usually means ending the mission once safe to do so and writing up the aircraft, but not catastrophic failure.

 

I think our point here is not about modeling the limits themselves, it’s about how it is implemented. Immediate and catastrophic failure when 1 second over the limit is not realistic. I think a more realistic way to model it would be a far more gradual damage to the aircraft, like if you exceed the 15sec limit for several minutes, or vastly exceed any other limit, you get a gradual reduction in power, with other secondary indications on the engine instruments that something is wrong - high oil pressures, high JPTs, etc. If you hold combat power for 15mins, there’s likely very little change to performance. Then, once you land, if you have exceeded any limits for any amount of time, you are not allowed to takeoff again in the same plane, you need to get a new one or end the mission.


Edited by Sandman1330
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I believe there will have to be some form of scripted degradation, I doubt anyone would be able to accurately simulate tolerances and variances in each turbine. I mean ED has a hard enough time with the regular damage model, let alone jet engine thermal wear and tear.

 

Zeus has stated they are working with a Harrier pilot, so hopefully they get it as close as possible.

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If this is truely an over limits thing then it should there. The only change I would hope for is maybe a more gradual increase in temps rather than a spike. Like over a minute or 2 so you have a chance to stop it or reduce total damage

 

 

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What I think could be done about this is to let the AC "auto-repair" Engine damage if you stay on the ground for X minutes, or with the "Repair" ground crew option. I know that's not entirely as it works IRL, but hey, is the "repair" realistic?

What I'm saying is that I'm OK with the engine actually getting the odd damage as it is currently doing, but I would like to be able to take-off again. At least after a repair...

 

Any thoughts?

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What I think could be done about this is to let the AC "auto-repair" Engine damage if you stay on the ground for X minutes, or with the "Repair" ground crew option. I know that's not entirely as it works IRL, but hey, is the "repair" realistic?

What I'm saying is that I'm OK with the engine actually getting the odd damage as it is currently doing, but I would like to be able to take-off again. At least after a repair...

 

Any thoughts?

Yeah i argee with the repair option. I broke my gear and boom it was fixed in seconds along with AAA damage... engine overheat should be repaired in the same way.

 

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I have not seen any of this, how hard are you guys pushing the engine? I do not think I ever had to be above 103% for anything.

To whom it may concern,

I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that.

Thank you for you patience.

 

 

Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..

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I'm not a pilot nor jet mechanic, here is my question. Some of the replies in this thread indicate that other aircraft can be operated out of limits with only engine life expectancy issues, do these engines also allow the pilot to overspeed the engine intentionally? Because it looks to me like the Harrier allows the pilot to exceed the maximum engine speed of 100% by simply applying more throttle all the way up to 116% of maximum engineered engine speed. This engine appears to be designed to be capable of this for very short periods of time though. Can a leer jet or a 747 run at a higher RPM than 100% by applying full throttle? Because if not then I don't believe the Harrier engine can really be compared to other jet engines. My experience has been that if I never exceed 100% engine speed or only do so for very short periods of time, the engine has no longevity/performance issues in game. Also this sucker usually has no problems taking off or landing at 100% engine speed, if I did encounter a problem though I'd know that I could push it up a bit if absolutely necessary.

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This, +1. The helicopter I fly in real life (CH146 Griffon) has many, many limits that are very easy to exceed. The vast majority of them exist for extended life cycle only, and in emergency or combat situations the aircraft has far more to give before reaching failure. I know people who have saved their aircraft and crew by vastly exceeding the limits; the aircraft did not fail or fall out of the sky. Of course, upon return the aircraft must undergo extensive inspections and maintenance action, including the reduction of the life length of many components and often a rebuild or replacement of affected components. However, exceeding limits does not result in an instant breaking of the airplane until you are vastly exceeding the limit or doing so for a lengthy time.

 

I realize we are not simulating the same aircraft here, but the philosophy has been the same in every aircraft I have ever flown, fixed wing or rotary wing.

 

If I’m in the middle of a dogfight, I’m going to use combat power - and I’m going to hold it longer than 10mins if it means losing the fight. The engine should not, and would not, catastrophically fail. However, when I got home from that fight, I’d hand the keys to maintenance and say sorry guys, broke that one... if I botch a hover landing and need to punch it to get myself back into a safe regime of flight, I have no doubt the aircraft would do it, I would just be required to land and hand that plane to maintenance as soon as possible. We exceed limits all the time, sometimes accidentally and sometimes intentionally to save the aircraft and crew. It usually means ending the mission once safe to do so and writing up the aircraft, but not catastrophic failure.

 

I think our point here is not about modeling the limits themselves, it’s about how it is implemented. Immediate and catastrophic failure when 1 second over the limit is not realistic. I think a more realistic way to model it would be a far more gradual damage to the aircraft, like if you exceed the 15sec limit for several minutes, or vastly exceed any other limit, you get a gradual reduction in power, with other secondary indications on the engine instruments that something is wrong - high oil pressures, high JPTs, etc. If you hold combat power for 15mins, there’s likely very little change to performance. Then, once you land, if you have exceeded any limits for any amount of time, you are not allowed to takeoff again in the same plane, you need to get a new one or end the mission.

 

Awesome post and spot on. Does anyone really think the engine is going to destroy itself seconds after reaching one of the limitation tables timed limits?

 

If so that limit has zero safety margin and why wouldn't the engine start degrading immediately? Why would it be fine at 9:59 and start a catastrophic meltdown at 10:01 that destroys its ability to make rated thrust in mere seconds? What changed in two seconds?

 

Anyway the same issue is being raised on the Belsimtek threads about the same type of scripted melting of the engine they have coded into the latest Huey update.

 

I think it strange that certain aircraft can't be made because a certain gov doesn't want them too. Others can't be made as we don't have access to documentation or everything is classified. So it seems they are striving for realism over guessing.

 

Except when it comes to engine operation. That we will guess about. Lacking any proof the engine melts at the table time limits - we hard code this destruction none the less.

 

Hell if your going to guess - guess me up a AH64 laser mavericks and a F16!

 

In this thread you have a Harrier mechanic saying they same thing I am. It will run at max power all day long. It will not damage the engine.

 

I fly Rolls Royce engines of a similar vintage to the Pegasus hundreds of hours a year. We are trained to use all the thrust if we need it. Yes. Push it to the stops. The engine control will protect the engine.

 

Anyway it's up to the developers to fix - I'd rather have a realistic Harrier/Pegasus simulation than a arcade level engine model scripted to self destruct. Sorry virtual pilots. You could turn of the JPTL or DECU if you really really want to destroy your engine.

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Aren't we all jumping the gun here?

 

To quote the developer's comments on the other forum he mentioned..

 

"Hi kayreez, I definitely can't rule out a bug since the powerplant modeling is pretty complex. However, keep in mind there are various engine "modes" and the DECU limits JPT and RPM based on those modes. For example with water switch on you get up to 116.8 RPM, however you are only allowed a very short amount of time to use that full RPM limit. Another example is COMBAT mode. You get a higher 111 RPM and associated JPT limit but your are in a regime that is a non-continuous engine limit at full power there. In addition, as you go faster the RPM limit value decreases. Even in non-combat, non-water (normal) engine power mode, you are able to get to 109 RPM above continuous max power of 102. Various RPM limits have different time limits before damage occurs that you can find in the flight manual. There is a safety factor put in above there but best to respect the time limits. So depending on what mode you are in your JPT and RPM limit and governing may differ.

There are a things are not modeled fully...DECU being off, MFS logic, JPT limiter switch off, Logic to disable JPT limiter when throttle pushed, and P3/Fuel Flow limiting behavior.

When you do get engine damage it is and can be subtle. When you go over RPM for too long you start to see an increase in JPT, a reduced capability to limit JPT, higher fuel flow, and less thrust. The longer you stay in the limit the more "damage" you are causing. The worst situation is having no water, but having the water switch on and going into max power at that setting.

Hope this helps and I'll review the code to make sure something else wonky isn't going on. "

 

Clearly this area is still being investigated, so these diatribes stating that this and that would or wouldn't happen is really beside the point. Until the devs say that they have checked, and the engine degradation model is working as advertised, your comments are frankly irrelevant.

 

The other side of this is the fact that if you go and cook an engine in real world operations, you'll be held to account for it. In DCS, there is no way to simulate a board of inquiry and grounding of a negligent pilot. How would you suggest we deal with engine damage if not by making it's performance degrade in subsequent flights?

 

No one is suggesting the current situation is how it will remain, so please try to keep things in perspective. I would also suggest that comparing a module made by a different developer is hardly relevant here either.


Edited by NeilWillis
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Clues to what actually happens when these limits are exceeded are all through the real manual. No warning or cautions of sudden loss of thrust or JPT spikes. Read the real manual. Takeoff - throttle -Full , accelerating transition Throttle - full. Once wingborne reduce power and extinguish 15 sec light turn off water.

 

Even running out of water with the switch on seems like a benign issue.

 

Chapter 11 - Flight Charactistics is very good reading. No mention of sudden engine Meltdown.

Even the OT light - Land as soon as practical (not immediate) and use minimum power. Does not warn you won't make thrust and will crash on landing. There are no warning about JPT spikes and sudden loss of thrust.

 

I like reading manuals and learning new aircraft. It's like learning a new language. I'm passionate about this issue because I love this aircraft and just hope to make a positive contribution to making as realistic as possible. Thanks.

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Awesome post and spot on. Does anyone really think the engine is going to destroy itself seconds after reaching one of the limitation tables timed limits?

 

If so that limit has zero safety margin and why wouldn't the engine start degrading immediately? Why would it be fine at 9:59 and start a catastrophic meltdown at 10:01 that destroys its ability to make rated thrust in mere seconds? What changed in two seconds?

 

Anyway the same issue is being raised on the Belsimtek threads about the same type of scripted melting of the engine they have coded into the latest Huey update.

 

I think it strange that certain aircraft can't be made because a certain gov doesn't want them too. Others can't be made as we don't have access to documentation or everything is classified. So it seems they are striving for realism over guessing.

 

Except when it comes to engine operation. That we will guess about. Lacking any proof the engine melts at the table time limits - we hard code this destruction none the less.

 

Hell if your going to guess - guess me up a AH64 laser mavericks and a F16!

 

In this thread you have a Harrier mechanic saying they same thing I am. It will run at max power all day long. It will not damage the engine.

 

I fly Rolls Royce engines of a similar vintage to the Pegasus hundreds of hours a year. We are trained to use all the thrust if we need it. Yes. Push it to the stops. The engine control will protect the engine.

 

Anyway it's up to the developers to fix - I'd rather have a realistic Harrier/Pegasus simulation than a arcade level engine model scripted to self destruct. Sorry virtual pilots. You could turn of the JPTL or DECU if you really really want to destroy your engine.

 

 

Clues to what actually happens when these limits are exceeded are all through the real manual. No warning or cautions of sudden loss of thrust or JPT spikes. Read the real manual. Takeoff - throttle -Full , accelerating transition Throttle - full. Once wingborne reduce power and extinguish 15 sec light turn off water.

 

Even running out of water with the switch on seems like a benign issue.

 

Chapter 11 - Flight Charactistics is very good reading. No mention of sudden engine Meltdown.

Even the OT light - Land as soon as practical (not immediate) and use minimum power. Does not warn you won't make thrust and will crash on landing. There are no warning about JPT spikes and sudden loss of thrust.

 

I like reading manuals and learning new aircraft. It's like learning a new language. I'm passionate about this issue because I love this aircraft and just hope to make a positive contribution to making as realistic as possible. Thanks.

 

 

 

+1 thumbup.gif


Edited by bart

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Aren't we all jumping the gun here?

 

To quote the developer's comments on the other forum he mentioned..

 

"Hi kayreez, I definitely can't rule out a bug since the powerplant modeling is pretty complex. However, keep in mind there are various engine "modes" and the DECU limits JPT and RPM based on those modes. For example with water switch on you get up to 116.8 RPM, however you are only allowed a very short amount of time to use that full RPM limit. Another example is COMBAT mode. You get a higher 111 RPM and associated JPT limit but your are in a regime that is a non-continuous engine limit at full power there. In addition, as you go faster the RPM limit value decreases. Even in non-combat, non-water (normal) engine power mode, you are able to get to 109 RPM above continuous max power of 102. Various RPM limits have different time limits before damage occurs that you can find in the flight manual. There is a safety factor put in above there but best to respect the time limits. So depending on what mode you are in your JPT and RPM limit and governing may differ.

There are a things are not modeled fully...DECU being off, MFS logic, JPT limiter switch off, Logic to disable JPT limiter when throttle pushed, and P3/Fuel Flow limiting behavior.

When you do get engine damage it is and can be subtle. When you go over RPM for too long you start to see an increase in JPT, a reduced capability to limit JPT, higher fuel flow, and less thrust. The longer you stay in the limit the more "damage" you are causing. The worst situation is having no water, but having the water switch on and going into max power at that setting.

Hope this helps and I'll review the code to make sure something else wonky isn't going on. "

 

Clearly this area is still being investigated, so these diatribes stating that this and that would or wouldn't happen is really beside the point. Until the devs say that they have checked, and the engine degradation model is working as advertised, your comments are frankly irrelevant.

 

The other side of this is the fact that if you go and cook an engine in real world operations, you'll be held to account for it. In DCS, there is no way to simulate a board of inquiry and grounding of a negligent pilot. How would you suggest we deal with engine damage if not by making it's performance degrade in subsequent flights?

 

No one is suggesting the current situation is how it will remain, so please try to keep things in perspective. I would also suggest that comparing a module made by a different developer is hardly relevant here either.

 

In truth, I think it is relevant. This is a bug forum, after all, and if it is not working as intended, then we are here to report it. That’s how this post actually started, with the assumption it is not working as intended.

 

I’ve never seen a pilot in front of a BOI for exceeding limits, because we don’t ever do it willy-nilly. If it is done, it is done for emergency or combat reasons, and the worst you’ll generally get is a ribbing from your buddies at the mess, especially if the reason you exceeded was due to a screw up elsewhere, like on approach to hover, and the only way to “save it” was to exceed limits.

 

If someone were to do it intentionally, when not required, it would be different. Still not a BOI, but some kind of disciplinary action or more likely remedial training would occur.

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Full throttle gives you 110% perhaps it is too much for it? But repair is repair.. period.

Broken, wore out, bearing scraping, fin wobbling, engine should be fixed good as new, when repair is done. I didn’t know that full throttle would hurt the engine, perhaps it should state so in the upcoming fixes?


Edited by Hermit713
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I had similar experiences where engine power drop what causes a on safe landing essentially dropping out of the sky when and Harry are mode although I didn’t take the engine overboard while taking off it’s just pretty much dropped out of the sky even though I thought maybe I did something wrong but then other times no issues whatsoever so perhaps there is something that causes it to degrade over a short time or is there a switch other than H2O switch that allows the engine to go above 110 percent or even 100 percent rpms? I’m not at a chance to find that in the pocket manual

 

In my experience, it seems that just having the throttle full forward will put you over the limit for indefinite sustained. And also, Any nozzle position other than 0 will also allow higher rpm.

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