Induced drag and its wing tip vortices are a direct consequence of the creation of lift by the wing.

Since the Coefficient of Lift is large when the Angle of Attack is large, induced drag is inversely proportional to the square of the speed whereas all other drag is directly proportional to the square of the speed.

The effect of this is that induced drag is relatively unimportant at high speed in the cruise and descent where it probably represents less than 10% of total drag. In the climb, it is more important representing at least 20% of total drag. At slow speeds just after take off and in the initial climb, it is of maximum importance and may produce as much as 70% of total drag.

Finally, when looking at the potential strength of wing tip vortices, all this theory on induced drag must be moderated by the effect of aircraft weight. Induced drag will always increase with aircraft weight.

They are aerodynamically efficient surfaces located at the wing tips, designed to reduce induced drag and increase fuel efficiency.

They increase efficiency by reducing the size of the wingtip vortices, which are created by the difference between the pressure on the upper surface of the wing and that on the lower surface.

35 ft

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)

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.

Yes, some directional control as we still have two functioning engines.

Drag penalties (additional weight)

Less controllability

Advection fog occurs when moist air passes over a cool surface by advection (wind) and is cooled.

It is common as a warm front passes over an area with significant snowpack, but it is most common at sea when tropical air encounters cooler waters, including areas of cold water upwelling, such as along the coast of California.

20.020 litres (twenty thousand and twenty litres), about 15 tons.

An aerofoil when placed in a flow will (normally) cause said flow to accelerate over the aerofoil and decelerate below it.

This will cause a pressure differential between the upper and lower surface of the aerofoil, and the resultant force will be applied at the center of pressure.

An ILS (Instrument Landing System) is defined as a precision runway approach aid based on two radio beams which together provide pilots with both vertical and horizontal guidance during an approach to land.

The ILS aerials transmit two lobes. For a pilot on final, the lobe to his right is modulated at a frequency of 150 Hz and the one to his left at 90 Hz. The point where the lobes meet is the centre line of the runway. As the signals on the lobe move from the centre line to either side, their amplitude increases. This means the magnitude of their depth modulation increases. The depth modulation can be considered as a percentage. For example, if an aircraft receives a 15% depth modulated signal from the left and a 5% depth modulated signal from the right, the difference of modulation becomes 10% to the left. This electrical imbalance is sent to the aircraft and the localizer needle is designed in such a way that it will show a deflection to the opposite direction, telling the pilot to go to the right.

When on the centre line, the modulation difference is zero and the needle centres itself.

The glide slope or the glide path provides the pilot with vertical guidance. The glide slope is set such that a glide slope angle of 3 degrees is maintained by the pilot. The needle of the slope moves up, if the aircraft is too low and moves down if it is too much above the required path. The glide slope is on the UHF band (329.15 - 335 Mhz).

The glide slope operates the same way as the localizer. The only difference is that the lobes are emitted on the vertical plane. The upper lobe is modulated at 90 Hz while the bottom one at 150 Hz. Exactly the same way as before, the needle of the slope moves based on the difference in depth modulation. As like before when the modulation difference is nil, the glide needle moves to the very centre of the instrument.