The point during a flight at which an aircraft is no longer capable of returning to the airfield from which it took off due to fuel considerations.

Beyond this point the aircraft must proceed to some other destination.

The critical engine of a multi-engine, fixed-wing propeller-driven aircraft is the one whose failure would result in the most adverse effects on the aircraft's handling and performance.

Due to the asymmetric blade effect (P-factor), the right-hand engine typically develops its resultant thrust vector at a greater lateral distance from the aircraft's C.G. than the left-hand engine.

The failure of the left-hand engine will result in a larger yaw effect via the operating right-hand engine, rather than vice-versa, and it is termed the Critical Engine. Since the operating right-hand engine produces a stronger yaw moment, the pilot will need to use larger control deflections in order to maintain aircraft control. Thus, the failure of the critical (left-hand) engine is less desirable than failure of the right-hand engine.

The operating right-hand engine will produce a more severe yaw towards the dead engine, thus making the failure of the left-hand engine critical.

Swept wings are designed to be the most effective at high speeds. At low speeds, a swept wing produces less lift than its straight counterpart.

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

A swept wing makes the velocity vector normal to the leading edge a shorter distance than the chordwise resultant.

Altimeter errors:

Instrument error Pressure error Time-lag error Barometric error

5000 litres

(4 tonnes / 0.8 = 5000 litters)

To notify the crew of the aircraft of a particular position on the IAP.

Locators have been largely replaced with Distance Measuring Equipment (DME), but they can sometimes be found associated with Outer or Middle Markers where they are referred to as Locator Outer Marker (LOM) or Locator Middle Marker (LMM).

They provide at least 1000ft clearance over obstacles within 25NM of the homing facility.

36,090ft in ISA