When an aircraft climbs, the static pressure in the instrument case decreases, which allows the enclosed capsule to expand.

This in turn moves the needle on the instrument to indicate a corresponding altitude.

During descent, the opposite function applies.

Altimeter errors can originate and vary from:

Instrument Pressure Time-lag Barometric Density Temperature Blocked static port

Altimeter errors:

Instrument error Pressure error Time-lag error Barometric error

Meridians converge from their maximum distance apart (at the equator) to the poles where they meet.

Great circles are the shortest distance between two points and convergency represents the change in direction experienced between those points.

A free turbine is a turbine that is not directly connected to the compressor. This allows the compressor to rotate at a different speed than the turbine. Since the turbine speed is coupled with the propeller, this allows for the propeller to be maintained at a constant ideal speed.

Another advantage is that free turbine engines can be designed to be more compact than their single shaft counterparts

Yes, with the modern high bypass turbofans the N1 compressor works as a huge propeller, it takes a big mass of air and gives it a relative small acceleration.

Around 70% of the air will bypass the core of the engine, only 30% of air will be compressed further and will eventually go through the combustion chamber.

Enhanced Ground Proximity Warning System, provides a greater level of detection than GPWS.

EGPWS is capable of ‘looking ahead’ to identify potential risks on the aircraft flight path as it includes a terrain and obstacle database.

You can go through a DA, but not a MDA.

A Decision Height, used in precision approaches, defines the point where a go around should be performed. It accounts for the altitude loss during the initial seconds of the go around maneuver.

The MDA does not account for this and assumes the pilot will never go below this altitude. When performing a CDFA most operators establish a Derived Decision altitude (DDA) to account for the extra lost altitude.

NDB errors:

Interference from other NDB’s

• Static, especially near thunderstorms

• Night effect Coastal refraction

• Mountain effect

• Aircraft quadrantal error

35 ft

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For Reference:

• 50ft for Class B or A (<15° AoB at take-off or normal landings)

• 35ft for Class A (dry take-off or steep approach)

• 15ft for Class A (wet take-off)

Fuel injection provides:

• Fuel free from vaporization ice

• Better economy through metered delivery

• More responsive and efficient engine

• Less maintenance