V1 is the decision speed (sometimes referred to as critical engine speed or critical engine failure speed) by which any decision to reject a takeoff must be made.

V2 is the takeoff safety speed which must be attained at the 35 ft height at the end of the required runway distance. This is essentially the best one-engine inoperative angle of climb speed for the airplane and is a minimum speed for flight in that condition until at least 400 ft above the ground. V2 shall be at least 1.1 times VMCA, and no less than 1.2 times VS.

Vr is defined as the speed at which the rotation of the aircraft should be initiated to takeoff attitude.

VMCA is the minimum control speed in the air and is defined as the minimum speed, whilst in the air, that directional control can be maintained with one engine inoperative (critical engine on two engine aerolanes), operating engine(s) at takeoff power and a maximum of 5 degrees of bank towards the good engine(s).

VMCG is the minimum control speed on the ground and is defined as the minimum speed, whilst on the ground, that directional control can be maintained, using only aerodynamic controls, with one engine inoperative (critical engine on two engine airplanes) and takeoff power applied on the other engine(s).

Jet streams are narrow bands of high-speed upper thermal winds at very high altitudes.

Flying at Vmd. At this speed the aircraft is flying at the maximum ratio of Lift and Drag, maximizing the potential energy consumption in terms of distance travelled.

The ratio between the wing span and the mean chord line.

A high aspect ratio is associated with good lift to drag ratio, i.e.: Gliders.

A low aspect ratio is usually associated with fast aircraft, i.e.: Fighter jets.

Dihedral is the upward inclinitation of the wing from the root to the tip.

Those are contrails.

The jet engine exhaust gases consist of carbon dioxide and water vapour.

At high altitudes the wator vapour gets released in a very cold environment. This can cause the air to be saturated with water vapour and then condenses. If cold enough the condense can freeze into white droplets. This forms the contrails.

A Mach trimmer is a system that artificially corrects for Mach tuck.

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)

To be the most efficient, aircraft descend at Vmd. Vmd increases with Weight, and therefore the rate of descent increases as well with weight.

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