Huey Engine Failure?

I know what the relation between collective and governor. But if you are an engineer, and your governor is constantly killing an engine - you go back to the drawing board. And they did! As Huey enthusiast, I had read and watched my share of Huey pilots memuars. And although they mentioned various downsides of Huey, noone ever talked about that you can kill it engine super easily, just pulling up the collective. In fact, they were talking about reliability of the machine. This makes me think, that Bell engineers weren't bunch of guys who had no idea what they are doing.

You don't consider that the reason they didn't talk about it was because they… you know… didn't do it? Because pulling full collective is just not something you do in normal flight?

The governor is not constantly killing the engine. The pilot asking for an amount of lift that the governor can only achieve by redwalling the engine… well, that redwalls the engine, just like the pilot asked. Redwalling the engine will very quickly kill it, irrespective of whether it's because the pilot plugs in that amount of throttle or if the governor does it. If that's not the desired outcome, then you don't do it. But sometimes — very rarely — you do want to do that, and the machine dutifully provides, so disallowing that use case would be a pretty bad design.

It's a helicopter. Killing the engine super-easily is part of the package. So you treat it well and only apply emergency measure if it's an emergency.

I imaging it's from the Max available torque in DCS compared to RL operations.

 

In DCS at sea level and the default 20°C OAT :

 

Max Torque is limited to approx 40 psi (917 hp) due to EGT, in RL the limit is 50 psi (1150 hp) due to the gearbox loading limit i.e. the DCS Huey should have an extra 10 psi (220 hp, 25%) available and even then, the limit is due to the gearbox limit, not EGT.

Ok, so it's sensible normal-use torque related to available torque. That makes a bit more sense, but we still arrive at the fact that it is available… just not for continuous use.

And just to mention the charts relate to a 1970ies/80ies UH-1H fresh from the factory. To get 100% realistic numbers you may want to set the Engine to 100% in the ME. Standard is 90% to account for the 40/50 year old engines...

The governor is not constantly killing the engine. The pilot asking for an amount of lift that the governor can only achieve by redwalling the engine… well, that redwalls the engine, just like the pilot asked.

This conception is nothing new in military vehicles, and usually called "emergency power", or something similar. And usually require special means to activate it. The fact that Huey have no emergency mode, and also that civilian Hueys are exactly the same as military ones, tells me that Huey governor is NOT designed to routinely kill the engine, as DCS Huey does.

Lehman - various people here have given you the truth. But if you do not want to listen to them, listen to me: I am a real life military helicopter pilot who flies the B412, which is basically an upgraded twin Huey.

I have 1000hrs in various helicopters, and have NEVER flown a helo in which you can pull 100% collective under power without exceeding some kind of limit. As my current aircraft is twin engine, that limit is usually torque. However, flying in summer in Iraq (40* C), my EGT was the limitation - even with 2 engines that are each more powerful than the one in the UH-1H.

I will not speak to current EGT modelling in DCS as I do not have any time in the H model Huey. However, the point I am trying to make is, at least with Bell aircraft, you will never pull 100% collective without exceeding an EGT (or ITT), torque or N1 limit - ever. The extra pull exists for emergency situations, I have friends who pulled almost 130% torque to save the aircraft from hitting the ground. The aircraft was then flat bedded home and the entire drivetrain had to be rebuilt, but he used that extra collective to save the aircraft and crew. It is there to sacrifice the aircraft to save your butt, pure and simple.

Comparing to the MI8, I hear some of the Russian aircraft are more solidly built and you can pull collective until the rotor droops without exceeding limits. Fine. That’s a design philosophy decision, where they have not left anything for emergencies. If my friend had been flying an aircraft like this that night, he and his crew would be dead.

Please listen to those who know, there are many posts here that clearly and correctly explain this.

Edit: before someone corrects me, I was incorrect in saying each engine on the B412 is more powerful than the one in the UH-1H. That only applies to earlier model Hueys, but the argument stands.

This conception is nothing new in military vehicles, and usually called "emergency power", or something similar. And usually require special means to activate it. The fact that Huey have no emergency mode, and also that civilian Hueys are exactly the same as military ones, tells me that Huey governor is NOT designed to routinely kill the engine, as DCS Huey does.

The way of presenting your arguments, the obvious lack of understanding the concept of the governor, throttle and what effect adding collective has on the Engine, tells me that you either lack the fundamental knowledge to make more than assumptions and speculation, or simply troll us / don't want to understand.

Sorry, but I will no longer waste my time here.

That’s a design philosophy decision, where they have not left anything for emergencies

This is where the problem lays. For me it is hard to grab the concept, that significant part of control input is deliberately made to be damaging to the machine. But if you say that it is really so for Bell helicopters - I'm not arguing anymore.

This is where the problem lays. For me it is hard to grab the concept, that significant part of control input is deliberately made to be damaging to the machine. But if say that it is really so for Bell helicopters - I'm not arguing anymore.

This design decision saved the lives of some of my friends, so I’m not complaining :)

This conception is nothing new in military vehicles, and usually called "emergency power", or something similar. And usually require special means to activate it. The fact that Huey have no emergency mode

Again, this just flat out incorrect. It is even marked as EMRG.

and also that civilian Hueys are exactly the same as military ones, tells me that Huey governor is NOT designed to routinely kill the engine, as DCS Huey does.

No. The governor does not routinely kill the engine. Pilot mismanagement of the engine does. You can do this in any civilian vehicle you care to get your hands on. If you routinely fly in such a way that you wreck your engine, the fault is not with the engine or governor or any part of the machine, but with your routine disregard of how to fly properly. It's really not more complicated than that.

This is where the problem lays. For me it is hard to grab the concept, that significant part of control input is deliberately made to be damaging to the machine. But if say that it is really so for Bell helicopters - I'm not arguing anymore.

If an engineer in most western society's constructs a bridge, he plans with a certain percentage stress resistence as required by the regulations, say 80 tons. If he is worth his money he will allow for exceeding the required limits up to 130% to 200% to ensure it can hold in an emergency, yet this situation will require to fix a lot of damage the bridge have taken without killing somebody.

Eastern philosophy is more like building the same bridge with a limit of 100 tons which is more and "better" than the 80 tons.

Only if a couple trucks or tanks with an overall load of 102 tons drive over the brifge... Well, you get the idea.

The throttle (gaspedal) in your car with a shift gears, can be put to the floor and overrev the engine... You are not supposed to go pedal to the metal in 1st gear, a simple limitation everybody follows without thought.

It is how it is and not a flaw.

So and so. As I've tested it again today, the OGE / IGE performance is pretty OK, you just need to be careful as you have a time constraint from the EGT, currently.

Unless something major has changed in the latest Open Beta patch - the torques required to hover OGE / IGE were close to the published charts.

However that is NOT the same as maximum available torque

... max torque available is pretty close to the charts.

Please post a track of a UH-1H (104% loadout, no need to takeoff) at a FARP at 4000ft / 8°C OAT (16°C at MSL) maintaining 50 psi torque on the gauge.

Note: When tested in 1.5.8 Max torque was 40 +/- 2 psi at 4000 ft / 8°C OAT and limited due to EGT.

https://forums.eagle.ru/attachment.php?attachmentid=176138&d=1515893895

Unless something major has changed in the latest Open Beta patch - the torques required to hover OGE / IGE were close to the published charts.

 

However that is NOT the same as maximum available torque

 

 

 

Please post a track of a UH-1H (104% loadout, no need to takeoff) at a FARP at 4000ft / 8°C OAT (16°C at MSL) maintaining 50 psi torque on the gauge.

 

Note: When tested in 1.5.8 Max torque was 40 +/- 2 psi at 4000 ft / 8°C OAT and limited due to EGT.

 

https://forums.eagle.ru/attachment.php?attachmentid=176138&d=1515893895

I am aware we are currently limited by the EGT getting critical, when going beyond 37 to 40 psi.

Still you can Take-Off (load out at maximum 112%), with 49-50 psi hold that for a while and then need to be careful as you are nearing the incorrect modeled EGT limits.

And sorry for the bad start was looking too much at the gauges :D

UH-1H_4kft_16degC_2992InHG_90eng.trk

Hm, ok maybe I can give a last analogy that helps to understand.

No need. My problem was, I couldn't understand why do we always have that much additional collective and power, that can't be normally used, so I was thinking that Huey is broken. Now that I know that it is intentional (and if you think about it, having some additional power always available is a smart thing for helicopters) - I know that DCS Huey is not broken, it is indeed become much better after implementation of EGT.

Anyway, it was a very long time since I had fried my Huey engine, it is not that hard to fly respecting the limits.

This is where the problem lays. For me it is hard to grab the concept, that significant part of control input is deliberately made to be damaging to the machine. But if you say that it is really so for Bell helicopters - I'm not arguing anymore.

However that is how it is at least for an R44, you have a significant amount of input that if used incorrectly can and will damage the aircraft with conciquences. You as the pilot need to apply any input in a very measured way so as not to damage the aircraft which includes engine and transmission and flight parameters, you are at liberty to push any and all parameters but there are concequences to your actions.

:)

in the latest openbeta release it feels like the engine power is much greater with the EGT in the green. I was able to fly over 100 knots with 50% fuel and front mini guns/door gunners today and the EGT was staying well in the green. Still had trouble at 4500 ft altitude but it didn't catch on fire but rather would not stay air born. I think that may be normal. Not sure how real hueys fly at higher altitude but I have always had problems with DCS hueys in the mountain tops.

slyfly

Is this a specific fix in this release? I didn't see it in the notes

https://forums.eagle.ru/showthread.php?p=3597281#post3597281

in the latest openbeta release it feels like the engine power is much greater with the EGT in the green. I was able to fly over 100 knots with 50% fuel and front mini guns/door gunners today and the EGT was staying well in the green. Still had trouble at 4500 ft altitude but it didn't catch on fire but rather would not stay air born. I think that may be normal. Not sure how real hueys fly at higher altitude but I have always had problems with DCS hueys in the mountain tops.

 

 

slyfly

i also noticed a diference in engine performance, but with no official report i`m not sure

there is definetly something has happened to the engine.

today i made some flight online and it didin't caused me any troubles. it flew like a charm, no exploding engines!

When they first introduced the new EGT limits I put the Huey aside. I couldn't even hover out of any LZs without exceeding them. Something has changed: Now you only red line your ship if you are in a massive hurry to leave a hot LZ and pull hard on the collective. I also noticed that the Huey needs more pedal now, sometimes I run out of left pedal, just like I read in books written by Huey pilots. Thank you for fixing it!

yes they have done quite a large change to the torque and egt.

you can do full power take offs in a full gunship now.

no need to stay in ground effect until you gain momentum

and I was pulling 45 torque in a cruise and it was barely half way to yellow.