Air brake (aeronautics)In aeronautics, air brakes or speed brakes are a type of flight control surface used on an aircraft to increase the drag on the aircraft. Air brakes differ from spoilers in that air brakes are designed to increase drag while making little change to lift, whereas spoilers reduce the lift-to-drag ratio and require a higher angle of attack to maintain lift, resulting in a higher stall speed. An air brake is a part of an aircraft. When extended into the airstream, it causes an increase in the drag on the aircraft.
Glider (aircraft)A glider is a fixed-wing aircraft that is supported in flight by the dynamic reaction of the air against its lifting surfaces, and whose free flight does not depend on an engine. Most gliders do not have an engine, although motor-gliders have small engines for extending their flight when necessary by sustaining the altitude (normally a sailplane relies on rising air to maintain altitude) with some being powerful enough to take off by self-launch.
Hang glidingHang gliding is an air sport or recreational activity in which a pilot flies a light, non-motorised foot-launched heavier-than-air aircraft called a hang glider. Most modern hang gliders are made of an aluminium alloy or composite frame covered with synthetic sailcloth to form a wing. Typically the pilot is in a harness suspended from the airframe, and controls the aircraft by shifting body weight in opposition to a control frame. Early hang gliders had a low lift-to-drag ratio, so pilots were restricted to gliding down small hills.
Wing tipA wing tip (or wingtip) is the part of the wing that is most distant from the fuselage of a fixed-wing aircraft. Because the wing tip shape influences the size and drag of the wingtip vortices, tip design has produced a diversity of shapes, including: Squared-off Aluminium tube bow Rounded Hoerner style Winglets Drooped tips Raked wingtips Tip tanks Sails Fences End plates Winglets have become popular additions to high speed aircraft to increase fuel efficiency by reducing drag from wingtip vortices.
VariometerIn aviation, a variometer – also known as a rate of climb and descent indicator (RCDI), rate-of-climb indicator, vertical speed indicator (VSI), or vertical velocity indicator (VVI) – is one of the flight instruments in an aircraft used to inform the pilot of the rate of descent or climb. It can be calibrated in metres per second, feet per minute (1 ft/min = 0.00508 m/s) or knots (1 kn ≈ 0.514 m/s), depending on country and type of aircraft. It is typically connected to the aircraft's external static pressure source.
GlidingGliding is a recreational activity and competitive air sport in which pilots fly unpowered aircraft known as gliders or sailplanes using naturally occurring currents of rising air in the atmosphere to remain airborne. The word soaring is also used for the sport. Gliding as a sport began in the 1920s. Initially the objective was to increase the duration of flights but soon pilots attempted cross-country flights away from the place of launch. Improvements in aerodynamics and in the understanding of weather phenomena have allowed greater distances at higher average speeds.
Spin (aerodynamics)In flight dynamics a spin is a special category of stall resulting in autorotation (uncommanded roll) about the aircraft's longitudinal axis and a shallow, rotating, downward path approximately centred on a vertical axis. Spins can be entered intentionally or unintentionally, from any flight attitude if the aircraft has sufficient yaw while at the stall point. In a normal spin, the wing on the inside of the turn stalls while the outside wing remains flying.
WasserkuppeThe is a mountain within the German state of Hesse. It is a large plateau formation at an elevation of and is the highest peak in the Rhön Mountains. Great advances in sailplane development took place on the mountain during the interwar period, driven by annual contests. Near the summit there is still an airfield used by gliding clubs and pilots of light aircraft. The German name is derived from Wasenkuppe, Asenberg or Weideberg and means Pasture mountain. The Wasserkuppe lies in the administrative district Fulda north of Gersfeld.
Coordinated flightIn aviation, coordinated flight of an aircraft is flight without sideslip. When an aircraft is flying with zero sideslip a turn and bank indicator installed on the aircraft's instrument panel usually shows the ball in the center of the spirit level. The occupants perceive no lateral acceleration of the aircraft and their weight to be acting straight downward into their seats. Particular care to maintain coordinated flight is required by the pilot when entering and leaving turns.
Wake turbulenceWake turbulence is a disturbance in the atmosphere that forms behind an aircraft as it passes through the air. It includes a variety of elements, the most significant of which are wingtip vortices and jetwash. Jetwash refers to the rapidly moving gases expelled from a jet engine; it is extremely turbulent but of short duration. Wingtip vortices, however, are much more stable and can remain in the air for up to three minutes after the passage of an aircraft. It is therefore not true turbulence in the aerodynamic sense, as true turbulence would be chaotic.