Can't reach KA-50's ceiling height

[spudinsky]

Obviously I'm doing something wrong, but what? The highest I've been able to get was 3500m, and only after ditching the missiles and rocket pods (before that, I could only reach 3200m). I can't get over the mountains in some of the missions. Can somebody explain how to operate the helicopter at high altitude? I couldn't find it in the pilot's manual.

[EtherealN]

Two things: weight and airspeed. You want to minimize weight (remember that this includes fuel, not only weapons and ammunition) and fly at your best-climb airspeed, which is 130km/h. Remember that this is IAS (Indicated Air Speed), not the Ground Speed displayed by your HUD.

 

The 130km/h is caused by factors that might be complex to explain, but basically it's a sweet spot between two types of drag affecting the aircraft, which means that you will have LESS lift if you come to a hover.

 

EDIT

Also, this explains part of it: L = ½ p v² A Cl, where L is lift, ½ is a constant, p (rho) is air density (roughly altitude), v² is the square of your True air speed (not Indicated), A is aerofoil area (for a helicopter I believe you can count the whole rotor disc), and Cl is the Coeficcient of Lift for the aerofoil (the rotor blades). From this we can see that increased speed generates more lift for a helicopter just as it does for a fixed wing aircraft. So as you speed up, you get more lift, but eventually you'll run into the Drag Wall since your Profile Drag (I think that's the english word for it, I get them mixed up in english) increases with speed faster than your lift.

Edited January 7, 2010 by EtherealN

[spudinsky]

It worked, thank you!

 

I started with 335 fuel and a couple of rocket pods, kept it at 130 IAS and reached 5,200m with 11% fuel left.

I had to keep reducing the collective a little bit each time the engine Set Lim orange lights came on in the overhead panel, and soon after reaching 5,200m the right hand engine spooled down and I started to lose height rapidly. It's not the first time that's happened to me. I think I had the de-icers on (engines and rotor blades) so I don't know what happened. The EKRAN indicated something about "Elec Accu" (because of loss of engine power to the electrical generator?).

[spudinsky]

I meant to say I started with 33 percent fuel.

[EtherealN]

A track file would help figuring out what happened. But 5200 meters is quite respectable. Do note however that there's a "de-ice" system as well as "anti-ice". The former is to remove ice that has already built up, the latter to prevent ice building up in the first place.

[spudinsky]

Thanks, I didn't realise the difference between de-ice and anti-ice. I suppose I should just use anti-ice (when EKRAN tells me to) so as to avoid bleeding more power than absolutely necessary from the engines.

If I have another engine failure, I'll save the track and send it to you.

[EtherealN]

Also, remember that you have some pitot anti-icers on the top panel, left of the engine anti-ice. These can be quite nice to run as well, since a frozen pitot may cause you to get erroneous speed and altitude data - or even none at all.

 

I'd also recommend the INU heater at the back right panel.

[spudinsky]

Sorry, I forgot to say that I also had the pitot anti-icers and INU heater on (I always turn on the INU heater as part of the start-up procedure).

 

Black Shark is a really great flight simulator!