Talk to me about RPM

[Fimble]

Hello, I'm a brand new BS flyer and being a regular fixed wing virtual flyer (I spend at least an hour a night in FreeFalcon5) you can imagine the learning curve when my aircraft suddenly has high speed, rotating wings... :cry:

 

In any event, I'm catching on fairly quickly but I am confused about the collective and engine RPM relationship. When I first got into the cockpit I had my Saitek's throttle control mapped to engine RPM and collective mapped to the slider. This was not ideal and have reversed that mapping since it appears the collective is constantly utilized and requires far more precision.

 

Long story short what do I need to know about engine RPM in the shark? Am I going to be constantly manipulating it or is it more of a set it to max and forget it?

 

With probably 20 minutes or so of actual flight time so far I am able to lift off, tool around the airfield a bit and touch back down, albeit none of it gracefully... :joystick:

[Itkovian]

Well, for one thing, you should just leave the throttle at auto, and not worry about it until you start taking damage (or are landing/taking of).

 

What you should worry about concerning RPMs is raising the collective so much that the engine RPM gets too low, which among other things will start killing your power (you'll lose your Shkval, among other things).

 

Another thing to worry about is moving too fast or making aggressive aerobatics. Those coaxial rotor blades tend to flex a bit, and you will notice that at high speed the right side of the lower rotor tends to ride up quite a bit, dangerously close to the upper rotor.

 

So if you move too quickly, or maneuver very aggressively, those rotors will start to intersect. You will know instantly when that happens. :)

 

The solution to avoiding that, aside from not exceeding 250 kph, is to actually lower the collective when making aggressive maneuvers or flying at extremely high speed (in a dive, for example). With the collective fully lowered you shouldn't have any rotor intersection (I'm sure someone can explain this phenomenon better than I, as well as the power loss, so I'm not even going to try *grin*).

 

I hope this helps.

 

Itkovian

 

P.S. Also, remember to keep at LEAST the roll and pitch AP channels on. They stabilize the Ka-50, and are an invaluable aid.

[Fimble]

Well, for one thing, you should just leave the throttle at auto, and not worry about it until you start taking damage (or are landing/taking of).

 

What you should worry about concerning RPMs is raising the collective so much that the engine RPM gets too low, which among other things will start killing your power (you'll lose your Shkval, among other things).

 

Another thing to worry about is moving too fast or making aggressive aerobatics. Those coaxial rotor blades tend to flex a bit, and you will notice that at high speed the right side of the lower rotor tends to ride up quite a bit, dangerously close to the upper rotor.

 

So if you move too quickly, or maneuver very aggressively, those rotors will start to intersect. You will know instantly when that happens. :)

 

The solution to avoiding that, aside from not exceeding 250 kph, is to actually lower the collective when making aggressive maneuvers or flying at extremely high speed (in a dive, for example). With the collective fully lowered you shouldn't have any rotor intersection (I'm sure someone can explain this phenomenon better than I, as well as the power loss, so I'm not even going to try *grin*).

 

I hope this helps.

 

Itkovian

 

P.S. Also, remember to keep at LEAST the roll and pitch AP channels on. They stabilize the Ka-50, and are an invaluable aid.

 

Thanks for the response! :)

 

I didn't know there was an AUTO setting for the throttle. Is this realistic or a feature of the sim alone? I don't think I care, just curious. And finally, since I won't be able to check for myself till much later tonight, what's the key command for auto-throttle?

[Sharkster64]

This is actually very realistic in all modern Helicopters. All modern helicopters have whats called a governor which governs the throttle. This will automatically increase throttle when the collective is raised, and it will decrease the throttle when the collective is lowered. The governor will always try to maintain a constant Rotor RPM. You still need to manually place the throttle in the auto position for the governor to work. Of course if you get battle damage and say lose an engine, you will have to manually place the throttle to the max position. If you lose both engines, you will have to manually lower the throttle all the way to auto rotate. To throttle up you press the "Page Up" button. To throttle down you press the "Page Down" button.

 

Hope this answers all your questions.

Edited October 14, 2010 by Sharkster64

[Bucic]

If Shark had a manual only throttle operation then it would finally be called a 100% unflyable by one man crew :)

[mvsgas]

Helicopters do not use engine RPM the same way as airplane. If you go to the FAA website you can download a very good and informative book that explains everything about helicopter flying. Also the manual for black shark will cover all of this.

 

Basically on old helicopter you had to constantly adjust the throttle to maintain a specific rotor RPM, which is the important RPM on a helicopter. Most modern helicopters use some form of engine control to do this, allowing the pilot to concentrate on flying the helicopter.

 

The collective control the pitch of the rotor, affecting the rpm consequently. The rotor RPM is the one you have to concern yourself with the most. Obviously you need engine rpm to maintain rotor RPM but int the KA-50 engine RPM is automaticaly control by FADEC.

 

All of this is a very brief generalization, you can find very good explanation on the DCS BS manual and here

 

DOUH!! I type to slow :D

Edited October 14, 2010 by mvsgas

[sobek]

FADEC

 

LOL, you whish :D

 

Edit: D'oh. i should get my memory checked

Edited October 14, 2010 by sobek

[mvsgas]

Already then, this is my retraction and correction; Engines are control by a Electronic Engine Governor (EEG) in the DCS KA-50

[Sharkster64]

Basically on old helicopter you had to constantly adjust the throttle to maintain a specific rotor RPM, which is the important RPM on a helicopter.

 

Reminds me of the good ole days flying the Bell-47. Constantly adjusting the throttle and the carb heat.

[Fimble]

Thanks fellas, I had done something between skimming and reading of the manual for an answer to this very question but didn't succeed. However these posts have explained it perfectly.

 

:book:

[Yo-Yo]

Already then, this is my retraction and correction; Engines are control by a Electronic Engine Governor (EEG) in the DCS KA-50

 

It's not very correct. All the job does old fashioned hydro-mechanical fuel governor requiring no DC power.

Electronic EEG is only a MAX power rating supervisor limiting GG rpm redarding atmosphere temperature and pressure. RT-12-6 is the second device that limits only EGT and they use the same electrical valve to limit fuel after fuel governor.

 

Fuel governor itself can limit max power but not so sophisticated as EEG.

 

And finally EEG can shut down the engines if rotor rpm gets dangerously high.

Edited October 14, 2010 by Yo-Yo

[mvsgas]

I quit! :D:joystick:

[Bucic]

:)