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24-420: During takeoff, the aircraft will accelerate along the runway, resting on its wheels, until its takeoff speed is reached, at which point the pilot manipulates the flight controls to make the aircraft pivot around the axis of its main landing gear while still on the ground, this increases the lift from the wings and effects takeoff. During landings , a commercial passenger-carrying aircraft will arrive over

48-523: A rocket is called "rocket launch". Launches for orbital spaceflights , or launches into interplanetary space , are usually from a fixed location on the ground, but may also be from a floating platform such as the San Marco platform , or the Sea Launch launch vessel. Rejected takeoff In aviation , a rejected takeoff ( RTO ) or aborted takeoff is the situation in which the pilot decides to abort

72-423: A runway overrun. Single-engine aircraft will reject any takeoff after an engine failure, regardless of speed, as there is no power available to continue the takeoff. Even if the airplane is already airborne, if sufficient runway remains, an attempt to land straight ahead on the runway may be made. This may also apply to some light twin-engine airplanes. Before the takeoff roll is started, the autobrake system of

96-406: A single-engine or light twin-engine aircraft, the pilot calculates the length of runway required to take off and clear any obstacles, to ensure sufficient runway to use for takeoff. A safety margin can be added to provide the option to stop on the runway in case of a rejected takeoff . In most such aircraft, any engine failure results in a rejected takeoff as a matter of course, since even overrunning

120-427: A takeoff. In the low-speed regime, usually below 80 kts or so, the takeoff will be rejected even for minor failures. In the high-speed regime, above usually 80 kts but below V 1 , minor problems are ignored, but the takeoff will still be rejected for serious problems, in particular for engine failures. The takeoff decision speed, known as V 1 , is calculated before each flight for larger multi-engine airplanes. Below

144-491: Is any system for helping aircraft into the air (as opposed to strictly under its own power). The reason it might be needed is due to the aircraft's weight exceeding the normal maximum takeoff weight , insufficient power, or the available runway length may be insufficient, or a hot and high airfield, or a combination of all four factors. Assisted takeoff is also required for gliders , which do not have an engine and so are unable to take off by themselves. Hence assisted takeoff

168-406: Is not in doubt, the takeoff is continued despite the (suspected) failure, and the airplane will attempt to land again as soon as possible. If the airplane's ability to fly is in doubt (for instance, in the event of a major flight-control failure which leaves the airplane unable to rotate for liftoff), the best option may well be to reject the takeoff even if after V 1 , accepting the likelihood of

192-465: Is permitted to accelerate to rotation speed (often referred to as V r ). The term rotation is used because the aircraft pivots around the axis of its main landing gear while still on the ground, usually because of gentle manipulation of the flight controls to make or facilitate this change in aircraft attitude (once proper air displacement occurs under / over the wings, an aircraft will lift off on its own; controls are to ease that in). The nose

216-520: Is raised to a nominal 5 ° –15° nose up pitch attitude to increase lift from the wings and effect liftoff. For most aircraft, attempting a takeoff without a pitch-up would require cruise speeds while still on the runway. Fixed-wing aircraft designed for high-speed operation (such as commercial jet aircraft ) have difficulty generating enough lift at the low speeds encountered during takeoff. These are therefore fitted with high-lift devices , often including slats and usually flaps , which increase

240-597: Is required. Vertical takeoff refers to aircraft or rockets that take off in a vertical trajectory . Vertical takeoff eliminates the need for airfields. Most vertical take off aircraft are also able to land horizontally, but there were certain rocket-powered aircraft of the Luftwaffe that only took off vertically, landing in other ways. The Bachem Ba 349 Natter landed under a parachute after having taken off vertically. Other late projects developed in Nazi Germany , such as

264-481: Is used during takeoff. Large transport category (airliner) aircraft may use a reduced power for takeoff, where less than full power is applied in order to prolong engine life, reduce maintenance costs and reduce noise emissions. In some emergency cases, the power used can then be increased to increase the aircraft's performance. Before takeoff, the engines, particularly piston engines , are routinely run up at high power to check for engine-related problems. The aircraft

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288-745: The Heinkel P.1077 Julia or the Focke-Wulf Volksjäger 2 , climbed to their ceiling at a nearly vertical angle and landed later on a skid. Vertical take-off and landing ( VTOL ) aircraft include fixed-wing aircraft that can hover, take off and land vertically as well as helicopters and other aircraft with powered rotors, such as tiltrotors . Some VTOL aircraft can operate in other modes as well, such as CTOL (conventional take-off and landing), STOL (short take-off and landing), and/or STOVL (short take-off and vertical landing). Others, such as some helicopters, can only operate by VTOL, due to

312-490: The camber and often area of the wing, making it more effective at low speed, thus creating more lift. These are deployed from the wing before takeoff, and retracted during the climb. They can also be deployed at other times, such as before landing. The takeoff speed required varies with aircraft weight and aircraft configuration (flap or slat position, as applicable), and is provided to the flight crew as indicated airspeed . Operations with transport category aircraft employ

336-536: The takeoff of an airplane after initiating the takeoff roll but before the airplane leaves the ground. Reasons to perform a rejected takeoff vary but are usually related to a suspected or actual problem with the aircraft, such as an engine failure; fire; incorrect configuration; aircraft control issue; unusually slow acceleration; automated warning signal(s) indicating a critical system failure; environmental conditions such as predictive windshear ; or an instruction from air traffic control . There are three phases of

360-524: The aircraft lacking landing gear that can handle horizontal motion. VTOL is a subset of V/STOL (vertical and/or short take-off and landing). Besides the helicopter, there are two types of VTOL aircraft in military service: craft using a tiltrotor , such as the Bell Boeing V-22 Osprey , and some aircraft using directed jet thrust such as the Harrier family . The takeoff phase of the flight of

384-429: The aircraft will gain the most altitude in the least amount of time. Generally speaking, V x is a lower speed than V y , and requires a higher pitch attitude to achieve. The speeds needed for takeoff are relative to the motion of the air ( indicated airspeed ). A headwind will reduce the ground speed needed for takeoff, as there is a greater flow of air over the wings. Typical takeoff air speeds for jetliners are in

408-426: The aircraft, if available, is armed. The autobrake system will automatically apply maximum brakes if throttle is reduced to idle or reverse thrust during the takeoff roll once a preset speed has been reached. An RTO is usually seen as one of the most challenging tests an airplane has to undergo for its certification trials . The RTO test is performed under the worst possible conditions; i.e. with fully worn out brakes,

432-441: The co-pilot calls V 1 , they will call V R or "rotate," marking speed at which to rotate the aircraft. The V R for transport category aircraft is calculated such as to allow the aircraft to reach the regulatory screen height at V 2 with one engine failed. Then, V 2 (the safe takeoff speed) is called. This speed must be maintained after an engine failure to meet performance targets for rate of climb and angle of climb. In

456-426: The concept of the takeoff V-speeds : V 1 , V R and V 2 . These speeds are determined not only by the above factors affecting takeoff performance, but also by the length and slope of the runway and any peculiar conditions, such as obstacles off the end of the runway. Below V 1 , in case of critical failures, the takeoff should be aborted; above V 1 the pilot continues the takeoff and returns for landing. After

480-421: The decision speed, the airplane should be able to stop safely before the end of the runway . Above the decision speed, the airplane may overshoot the runway if the takeoff is aborted, and, therefore, a rejected takeoff is normally not performed above this speed, unless there is reason to doubt the airplane's ability to fly. If a serious failure occurs or is suspected above V 1 , but the airplane's ability to fly

504-425: The end of the runway is preferable to lifting off with insufficient power to maintain flight. If an obstacle needs to be cleared, the pilot climbs at the speed for maximum climb angle (V x ), which results in the greatest altitude gain per unit of horizontal distance travelled. If no obstacle needs to be cleared, or after an obstacle is cleared, the pilot can accelerate to the best rate of climb speed (V y ), where

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528-506: The ground and becomes airborne. For aircraft traveling vertically, this is known as liftoff . For aircraft that take off horizontally, this usually involves starting with a transition from moving along the ground on a runway . For balloons , helicopters and some specialized fixed-wing aircraft ( VTOL aircraft such as the Harrier and the Bell Boeing V22 Osprey ), no runway is needed. For light aircraft , usually full power

552-525: The range of 240–285  km/h (130–154  kn ; 149–177  mph ). Light aircraft, such as a Cessna 150 , take off at around 100  km/h (54  kn ; 62  mph ). Ultralights have even lower takeoff speeds. For a given aircraft, the takeoff speed is usually dependent on the aircraft weight; the heavier the weight, the greater the speed needed. Some aircraft are specifically designed for short takeoff and landing (STOL) , which they achieve by becoming airborne at very low speeds. Assisted takeoff

576-408: The runway while still at flight speed. The landing consists of the final approach phase, the flare , the touchdown, and roll-out phase. Seaplanes and amphibious aircraft , instead of using runways, use water . This aviation -related article is a stub . You can help Misplaced Pages by expanding it . Takeoff Takeoff is the phase of flight in which an aerospace vehicle leaves

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