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Where traffic is not an issue, cruise climbs may still be used. The [[Concorde]], for example, used a continuous cruise climb throughout its flights, since there was never any other traffic at the same altitude (nearly 60,000 feet) in the same direction. |
Where traffic is not an issue, cruise climbs may still be used. The [[Concorde]], for example, used a continuous cruise climb throughout its flights, since there was never any other traffic at the same altitude (nearly 60,000 feet) in the same direction. |
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In most modern commercial airliners, computers such as [[flight management system]]s calculate and/or execute the proper steps in a step climb, in order to maximize the efficiency realized by the technique. |
In most modern commercial airliners, computers such as [[flight management system]]s ([[FMS]]) calculate and/or execute the proper steps in a step climb, in order to maximize the efficiency realized by the technique. |
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* except in [[Hapag-Lloyd Flight 3378]] - July 12, 2000 - [[Airbus A310-300]] - [[Fuel starvation]] |
* except in [[Hapag-Lloyd Flight 3378]] - July 12, 2000 - [[Airbus A310-300]] - [[Fuel starvation]] |
Inaviation, a step climb is a gradual climb from one cruise altitude to another in fixed steps, intended to keep an aircraft flying at the most efficient cruise altitude possible.
Since the early days of jet aircraft and commercial travel, the technique of gradually climbing in cruise altitude as fuel burns off and the aircraft becomes lighter has been widely used by pilots. The altitude that provides the most fuel-efficient cruise at the start of a long flight, when the aircraft is fully loaded with fuel, is not the same as the altitude that provides the best efficiency at the end of the flight, when most of the fuel aboard has been burned. This latter altitude is usually significantly higher than the former. By climbing gradually throughout the cruise phase of a flight, pilots can make the most economical use of their fuel.
Originally, a simple cruise climb was used by pilots. This amounted to a simple, continuous, very gradual climb from an initial cruise altitude to a final cruise altitude, and made the most efficient use of fuel. However, with increasing air traffic and the assignment of distinct flight levels to specific flights, airways, and directions of flight, it is no longer safe to climb continuously in this way, and so most flights compromise by climbing in distinct steps—a step climb—with ATC approval, in order to ensure that the aircraft is always at an appropriate altitude for traffic control. While not quite as efficient as a continuous cruise climb, step climbs are still more efficient than maintaining a single altitude throughout a flight. Usually 4,000 feet intervals step climbs are used to comply with the semicircular/hemispheric rule that apply to flight level.
Where traffic is not an issue, cruise climbs may still be used. The Concorde, for example, used a continuous cruise climb throughout its flights, since there was never any other traffic at the same altitude (nearly 60,000 feet) in the same direction.
In most modern commercial airliners, computers such as flight management systems (FMS) calculate and/or execute the proper steps in a step climb, in order to maximize the efficiency realized by the technique.
Step and cruise climbs are not normally applicable to lower-flying aircraft propelled by conventional piston engines with propellersorturboprops, since their performance characteristics may be very different from those of TurbofanorJet engined aircraft. In fact, the most efficient altitude for a small general-aviation aircraft may be only a few thousand feet above the ground, and increasing altitude may diminish efficiency rather than improve it.