Charts of engine performance

[kimkiller]

In several missions you are advised to look at how mountanious terrain impact your engine performance.

I can´t find any charts in the manual with that infromation.

 

Does anyone know where I can find these charts?

[EtherealN]

I'm not sure if it is the one meant here, but there is a chart on the left side (I think it was left side) of the cockpit where you can crossreference temperature and altitude and get a top speed. Since maintaining a given speed while also maintaining the altitude will place demands on your engines being able to supply the power, this might be what is meant.

 

I haven't found any direct charts for the engines that correlate with altitude, though.

[Frederf]

The terrain doesn't impact the engine... well it can but if that happens you have bigger problems to worry about. Temperature and altitude are your primary concerns, moisture secondary.

 

There are some charts around here for the TXXXX (I forget the model number) series engine on these forums. It isn't specific to the Ka-50 but it is the proper engine (which is used in a lot of helicopters).

[kimkiller]

No, the chart on the left door isn't helping me.

 

What I'm trying to get is charts on how pressure (altitude) and temperature impacts engine performance like Frederf says.

 

In a mission I flew you need to clear a ridge that is located over 4500 m.

I'm having trouble to clear it without overspeeding the engines.

 

I can maintain 4300 m without overspeeding the engine and if I trade speed for altitude I can get it as high as 4500-4600 without overspeeding the engines but when the speed has dropped below 180 km/h I start to sink.

 

Since you get the advise to look it up in the mission briefing I assumed that there had to be a chart somewhere in the manual but I can't find it.

[AlphaOneSix]

It's not in the manual anywhere.

 

I have power charts for the TV3-117VM and TV3-117MT, but the Ka-50 has the TV3-117VMA, so those won't help.

 

Best bet will be to reduce your fuel and/or armament load, you probably won't be able to get over the ridge with a full load.

[kimkiller]

I have managed to get over but at the cost of overspeeding the engines.

 

Often in helicopters you have a timelimit (2 min. at 92% in CH46)at a certain amount of torque that you can use at takeoff and another, lower torque (85% in CH46), that you can maintain continously.

 

But there are differences in how you keep track on how much power you use from the engine.

 

In CH46 you have 3 limitations to how much power you can use from the engines.

First you have the torque that is limited by how much the transmission can accept.

Second you have the temperature that the engine can withstand.

Third is the rpm of the engine.

 

Do you know at what speed the KA-50 have the best climbrate?

Edited May 12, 2009 by kimkiller

[m0jo]

Do you know at what speed the KA-50 have the best climbrate?

130 km/h IAS

[kimkiller]

Thanks a lot mOjo.:thumbup:

[AlphaOneSix]

I have managed to get over but at the cost of overspeeding the engines.

 

With the engine governors operating, you will not be able to get more than 101.15% N1, which doesn't count as an overspeed. Beyond that is overspeed territory, which should only be attainable with the governors off.

 

To get the best picture of your current power condition, look at your EPR gauge on the right panel. When the yellow needles are at or below the "K" marker, you are in cruise power, which has no time limit. Between the "K" and the "H" markers, you are in max continuous power (also called limited cruise or nominal power), which has a 60 minute time limit. Between the "H" and the "B" markers, you are in takeoff power, which has a 6 minute time limit. With the engine governors operating, you will not be able to get more power than that, unless one of the engines fail.