User manual

DodoSim 206 FSX User Manual

Page 30

3.3.4.2 Navigation Instruments

6. Horizontal Situation Indicator (HSI)- The HSI combines both the directional gyro and VOR

display, indicating the relative deviation to the tuned VOR localiser radio transmitter.

7. VOR Indicator – The VOR instrument displays the relative course deviation to or from the

tuned VOR localiser.

8. ADF Indicator – The ADF indicator is used to locate the direction to the tuned Non-

Directional Beacon (NDB.)

Hint: For information on how to use the navigation instruments, refer to FSX’s “Learning

Center” or refer to any number of real-life pilot training manuals.

Though out of print, Microsoft’s book “Instrument Flight Techniques with Microsoft Flight

Simulator 98” is an excellent resource for the simulator pilot.

3.3.4.3 Engine Instruments

9. Gas Producer (N1) speed - Indicates the speed of the compressor turbine as a

percentage. It will vary depending on engine loading.

10. Exhaust Gas Temperature (EGT) - Also sometimes called TOT, (Turbine Output

Temperature), this displays the temperature of the exhaust gases and is displayed in

degrees Celsius. The gauge also includes the Over-Temp Light, which illuminates once

operating limits have been exceeded, (10 seconds above 812°C or 1 second above

927°C), and can only be reset by a service engineer using the “Service helicopter” dialog.

11. Power Turbine (N2) and Rotor (NR) speeds - This gauge contains two needles, and

displays both the power turbine and rotor speed as a percentage. During normal flight the

N2 and NR should align closely. If the NR is forced down when manoeuvring, the

governor will increase fuel supply to the engine, which will drive the N1 and N2 to bring the

rotor RPM back up. Likewise, if the rotor over-speeds, the governor will reduce fuel input

and the N1 and N2 will decrease, allowing the rotor to slow down.

The power turbine drives the rotor gearbox via a one-way “sprag” clutch. Therefore the N2

can drive the NR up and the NR can drive the N2 down, but not vice-versa. (i.e. Unless the

clutch has failed, the NR can never go slower than the N2.)

If the pilot reduces the throttle, (after landing or to perform an auto-rotation), the N2 speed

decays faster than the NR and the needles “split” when the one-way clutch disengages.

12. Torque meter - Torque is a measure of the twisting force applied by the engine on the

transmission. As more power is demanded via the collective, (and anti-torque pedals

which also exert a torque force when their pitch is increased), the torque value increases.

Serious damage can occur to the transmission and airframe if the aircraft is substantially or

regularly over-torqued. Torque can become a limiting factor in hot or high conditions or

where the aircraft is heavily laden. In these cases the pilot may well run out of torque

before he is able to lift off the ground and the pilots may be required to perform running

take-off and landings if possible.

13. Engine Oil Temperature & Pressure - This dual gauge displays both the temperature and

pressure of the engine oil. If the engine has sustained damage due to misuse, (i.e. hot

starts or operating too hard in adverse atmospheric conditions), then these gauges could

be your first indication that it may be on the way to failing.