Engine tends to break too easily

Hello folks,

Well, I just find the engine too sensitive. The problem maybe comes from my joystick as it has some "cranks" position (idle & afterburners). Putting the throttle into one of those crank makes the collective to jump quickly from a position to another resulting as an engine failure in many cases which drove me mad multiple times. So I wanted to know if it would be possible to adjust the engine sensitivity, makin' it stronger... or at least put an option to disable this feature as not everyone can afford a Warthog with descent axis tuning. I tried to put "X Saturation" and even curves on the throttle axis but it's a no-go, issues remain.

Thanks.

eeehm, there is no need to use the throttle in the Gazelle. The engine will regulate its RPM fine by itself, make sure the fuel flow handle is fully depressed.

Secondly, I'm guessing you don't mean the throttle but the collective, it's the big handle to the left of the pilot in the Gazelle. The collective controls the angle of attack of the rotor blades, or, more specific, how much they "bite" into the air while rotating.

Since the Gazelle is a nimble bird, she responds very fast to control inputs. Like any helicopter she wants to fly in an unstable state and it's your job to avoid overcontrolling or any rash or fast control inputs.

When you push your throttle quadrant into the afterburner section, you're basically yanking on the collective and the helicopter repons accordingly by literally jumping up. But by doing this, the rotor RPM drops, the engine regulator injects more fuel into the engine in order to try to bring the rotor RPM up to the required level. More specific, you're asking the engine to generate more torque.

Torque is the gremlin of the helicopter as anything above 100% torque is generally speaking a bad thing for any engine.

Maybe your software for your throttle allows the setting of the bandwidth where it operates? With that, you can set the collective anywhere between 0 and 100% without going into the AB parts of the throttle?

Why about not using your throttle axis then and assign the throttle controls to some buttons of your joystick so you get a smoother control of the RPM? Actually, why even bother to have RPM control on the joystick and just use the keyboard or mouse since the only time you need to control the turbine RPM is for start up and shut down? You never touch this yellow lever during flight.

Or are you referring to the collective?

It's kinda of a long shot to ask to modify the way a DCS module is implemented just because your joystick axis is not answering properly.

eeehm, there is no need to use the throttle in the Gazelle. The engine will regulate its RPM fine by itself, make sure the fuel flow handle is fully depressed.

 

Secondly, I'm guessing you don't mean the throttle but the collective, it's the big handle to the left of the pilot in the Gazelle. The collective controls the angle of attack of the rotor blades, or, more specific, how much they "bite" into the air while rotating.

 

Since the Gazelle is a nimble bird, she responds very fast to control inputs. Like any helicopter she wants to fly in an unstable state and it's your job to avoid overcontrolling or any rash or fast control inputs.

 

When you push your throttle quadrant into the afterburner section, you're basically yanking on the collective and the helicopter repons accordingly by literally jumping up. But by doing this, the rotor RPM drops, the engine regulator injects more fuel into the engine in order to try to bring the rotor RPM up to the required level. More specific, you're asking the engine to generate more torque.

 

Torque is the gremlin of the helicopter as anything above 100% torque is generally speaking a bad thing for any engine.

 

Maybe your software for your throttle allows the setting of the bandwidth where it operates? With that, you can set the collective anywhere between 0 and 100% without going into the AB parts of the throttle?

When I said throttle I'm refering to my joystick throttle not the collective. The crank it has makes the collective to suddenly jump a bit for some milliseconds which lead sometimes to an engine failure or a loss of power. I'm never using the AB part of the throttle, except in case of emergency situation such as ground/object avoidance, anyway no one flies an helicopter with 100% of torque except on Battlefield. I'm just wondering if the engine is that sensitive on the real helicopter.

Why about not using your throttle axis then and assign the throttle controls to some buttons of your joystick so you get a smoother control of the RPM? Actually, why even bother to have RPM control on the joystick and just use the keyboard or mouse since the only time you need to control the turbine RPM is for start up and shut down? You never touch this yellow lever during flight.

Or are you referring to the collective?

 

It's kinda of a long shot to ask to modify the way a DCS module is implemented just because your joystick axis is not answering properly.

Post edited to avoid confusion. In fact that's the collective position that jumps, due to the inputs of my physical throttle position. Anyone with the same kind of stick may confirm this "issue" ?

ahh, the Thrustmaster Hotas X throttle it has a dead zone & a bump stop in the middle of the swing, you can't get rid of the dead zone as that's on the potentiometer, but you can get rid of the bump by opening the base and filing down the bump on the bottom of the guide cup

ahh, the Thrustmaster t1600M is the same as the Hotas X it has a dead zone & a bump stop in the middle of the swing, you can't get rid of the dead zone as that's on the potentiometer, but you can get rid of the bump by opening the base and filing down the bump on the bottom of the guide cup

Holly molly !! :huh:

yeah old issue, search for T.Fight Hotas X mod and you find links & videos how to do it it's fairly simple to do

the dead zone is the main killer though there's about .5cm to 1cm gap in the middle where iirc the throttle swaps sides on the pot, you could probably mod out by changing the pot for a better continious pot or a Hall effect sensor but that's a lot pf headache for a cheap stick.

yeah old issue, search for T.Fight Hotas X mod and you find links & videos how to do it it's fairly simple to do

 

the dead zone is the main killer though there's about .5cm to 1cm gap in the middle where iirc the throttle swaps sides on the pot, you could probably mod out by changing the pot for a better continious pot or a Hall effect sensor but that's a lot pf headache for a cheap stick.

Better get a new one I guess... :cry:

@Sacha, vu qu'on est voisins (suis de montpel aussi), pour t'expliquer :

La Gazelle utilise le principe de la turbine liée.

De manière très simple, sur un hélico classique (comme le Kamov), tu as une boite de transmission relativement complexe qui va changer de "rapport" en fonction des efforts demandés à la machine. C'est un peu le même principe qu'en bagnole.

Ça se fait au détriment d'une chose : les RPM Rotor, ceux-ci vont s'ajuster en même temps que la boite de transmission et de fait, tu peux, sur une manoeuvre un peu brusque, te retrouver en limite RPM et tomber comme une pierre (Mise en stationnaire trop violente par exemple).

Sur la Gazelle, ta boite de transmission est un simple réducteur. En d'autres termes, tu n'as pas de "passage de vitesse" lorsque tu demandes trop d'effort. L'avantage c'est la simplicité de fab, d'entretien, la légèreté, et d'avoir des RPM en permanence synchro (donc pas de perte de RPM rotor en vol sauf cas grave). Le désavantage, c'est que comme y'a pas d'adaptation aux efforts, ça pète plus vite.

Surveille ta T4 plus que ton couple, ce dernier n'est qu'indicatif et les conditions de surcouple dépendent en pratique de tes conditions de vol, ça peut arriver à 90% comme à 105%. En revanche, ta T4 elle, te donne la température GTM, si tu passes la barre rouge, alors c'est pas bon. Si t'es en surchauffe à 650-700 °C, t'as plusieurs cas de figure qui vont arriver très rapidement. Soit la destruction pure et simple de ta BTP (boite de transmission principale), soit un fluage (Les aubes de la turbine se dilatent et viennent taper le bâti vers l'extérieur), ou tout simplement un feu moteur.

Dans tous les cas, t'en as pour 10 à 25 secondes en surchauffe franche pour tout casser.

M'enfin tu trouveras peu ou prou la même documentation dans le manuel, vu que j'ai dû compléter cette partie là ;)

Pour le reste, ton pépin joystick est assez commun, tu trouveras un moyen de le régler sans problème.

Nicolas

Wow. Very interesting answer Dimi. :thumbup:

Feel sorry for the non French speaking people now. :D

I learnt to speak english at school, they had to do the same with french :megalol:

@Sacha, vu qu'on est voisins (suis de montpel aussi), pour t'expliquer :

 

La Gazelle utilise le principe de la turbine liée.

 

De manière très simple, sur un hélico classique (comme le Kamov), tu as une boite de transmission relativement complexe qui va changer de "rapport" en fonction des efforts demandés à la machine. C'est un peu le même principe qu'en bagnole.

 

Ça se fait au détriment d'une chose : les RPM Rotor, ceux-ci vont s'ajuster en même temps que la boite de transmission et de fait, tu peux, sur une manoeuvre un peu brusque, te retrouver en limite RPM et tomber comme une pierre (Mise en stationnaire trop violente par exemple).

 

Sur la Gazelle, ta boite de transmission est un simple réducteur. En d'autres termes, tu n'as pas de "passage de vitesse" lorsque tu demandes trop d'effort. L'avantage c'est la simplicité de fab, d'entretien, la légèreté, et d'avoir des RPM en permanence synchro (donc pas de perte de RPM rotor en vol sauf cas grave). Le désavantage, c'est que comme y'a pas d'adaptation aux efforts, ça pète plus vite.

 

Surveille ta T4 plus que ton couple, ce dernier n'est qu'indicatif et les conditions de surcouple dépendent en pratique de tes conditions de vol, ça peut arriver à 90% comme à 105%. En revanche, ta T4 elle, te donne la température GTM, si tu passes la barre rouge, alors c'est pas bon. Si t'es en surchauffe à 650-700 °C, t'as plusieurs cas de figure qui vont arriver très rapidement. Soit la destruction pure et simple de ta BTP (boite de transmission principale), soit un fluage (Les aubes de la turbine se dilatent et viennent taper le bâti vers l'extérieur), ou tout simplement un feu moteur.

 

Dans tous les cas, t'en as pour 10 à 25 secondes en surchauffe franche pour tout casser.

 

M'enfin tu trouveras peu ou prou la même documentation dans le manuel, vu que j'ai dû compléter cette partie là ;)

 

Pour le reste, ton pépin joystick est assez commun, tu trouveras un moyen de le régler sans problème.

 

Nicolas

Merci pour les précisions, j'étais au courant pour ces points techniques de manière générale m'enfin un rappel ça fait toujours du bien. Je pense qu'il s'agit avant tout d'un problème de joystick et pas un défaut de l'appareil. Les crans font bouger brusquement le collectif par des mouvements parasites relativement espacés, ce qui génèrent des problèmes moteur. L'objet de ma demande concernait avant tout la possibilité de désactiver ou d'atténuer ces effets là afin de palier à ce genre de problèmes de matériels (qui plus-est semblent assez récurrent d'après toi). Pour le reste, ce serait cool qu'on se capte du coups ! :smilewink:

sur un hélico classique (comme le Kamov)

:megalol:

Sorry :D

Schade, dass ich kein französisch spreche.

Ich kann Deutsches sprechen :)

Pero quiza prefieres en espanol !

Well ok, let's stay in english, everyone will understand :megalol:

With great power comes great responsibility. Don't push the engine too hard or she'll taker her union mandated break and you'll be a sinking brick.

Yeah something strange is going on since the previous update. If you're flying along and quickly lower the collective, the T4 will spike for no apparent reason and then the engine blows.

Will test this...but will need all the info from the bug report thread filled out so we can work on this.

Yeah something strange is going on since the previous update. If you're flying along and quickly lower the collective, the T4 will spike for no apparent reason and then the engine blows.

I have blown 4 engines in the gazelle due to flying at a FAT of 34 degs in NTTR. I truly stressed the engines in a hover at this temp!

I have blown 2 engines in the MI-8 at this temp... and they go with a very satisfying Bang!

I have had the ka-50 engines wind down twice on a snipe position due to this FAT temperature problem.

All is good for me, are you sure you are managing your engines properly?

Will test this...but will need all the info from the bug report thread filled out so we can work on this.

Description: Quickly lowering the collective causes T4 to spike, killing engine.

DCS Version: 1.5.3.53108 and the previous open beta release

Steam: No

Map: Black Sea

SP/MP: Both

Reproducible: Yes

Step to Reproduce: Fly along with T4 in the yellow, quickly reduce the collective to zero, watch T4 spike and your engine die.

Track Available: Attached

Mission File: Happens with all missions, hot or cold start

Controllers: TM Warthog, no axis tuning done to collective.

Mods: None

gazelle engine death.trk

Thanks. Will test this weekend.

Description: Quickly lowering the collective causes T4 to spike, killing engine.

DCS Version: 1.5.3.53108 and the previous open beta release

Steam: No

Map: Black Sea

SP/MP: Both

Reproducible: Yes

Step to Reproduce: Fly along with T4 in the yellow, quickly reduce the collective to zero, watch T4 spike and your engine die.

Track Available: Attached

Mission File: Happens with all missions, hot or cold start

Controllers: TM Warthog, no axis tuning done to collective.

Mods: None

Chcek first rotor RPM. Rotor RPM overspeed will cause the transmission gearbox to overheat.

Two separate failures, rotor RPM does not change when this occurs. I can't even seem to get the rotor to overspeed if I put myself in a hover 500m up and slowly lower the collective to zero and freefall, it speeds up a little but not outside of it's normal operating range.

Most of the time in normal flight this isn't an issue, however I had spent a lot of time on the 104th earlier this morning, I was in the target area and dodging some enemy fire, I went to hide behind some buildings and accidentally lowered the collective a bit too fast in an attempt to stop and that was it, engine died and I fell to my doom. Frustrating.

Ok tested and got an engineering answer for you. So here's whats going on:

If you decrease the collective from above 68% to 0 in less then 1 second, the rotor and engine desync. So this would basically be like pushing the fuel lever all the way open at startup and blowing up the engine.