GB2140363A - Airfields and a method of controlling aircraft traffic using such airfields - Google Patents

Abstract

The airfield has a main runway 1 with a straight take-off portion 2. A plurality of additional curved or angled take-off paths 4, 5, 6 and 7 are located on the sides of the main runway 1 so as to merge generally tangentially with the main runway to provide a plurality of take-off paths. <IMAGE>

Description

SPECIFICATION Airfields and a method of controlling:air- craft traffic using such airfields This invention relates to airfields and particu larly to a novel layout for airfields which increases the maximum capacity of the airfi eld, i.e, to enable a much greater number of aircraft to use the airffield within a given time.

Because of the increasing popularity of flying both for business and pleasure pur poses, existing airfields throughout the world are frequently being used at or approaching their maximum capacity. One conventional method of increasing the maximum capacity of an airffield is to build an additional runway.

Alternatively, where such expansion is not possible at an existing airfield, additional airfields need to be built. The building of a new runway and, even more so, the building of a new airfield is an extremely expensive operation and also necessitates the use of a large amount of land. For practical and economic reasons, new airfields in particular, have to use "green field" land which is extremely unpopular from an environmental point of view. Many existing runways in existing airfields are close to our surrounded by urban development which not only leads to objections of noise but, if further runways are built, also necessitates the demolition of buildings etc., which, again, is extremely expensive and unpopular with public opinion.

The present invention seeks to provide a new design for airfields, which can be readily adapted to be incorporated in existing airfields to markedly increase the maximum capacity of the airfield, in terms of the number of takeoffs that the airfield can cope with, with a minimum of disturbance and a minimum requirement for extra land. The invention also seeks to provide a method of controlling aircraft traffic utilising such an airfield.

Normally, an aircraft taking-off at its maximum allowed weight for the runway length available will make use of the full length available. In practice, this means that the aircraft will move slowly along a perimeter track before turning on a 90 intersection on to the end of the runway. In some instances, aircraft even have to taxi slowly down the runway to the extreme end before making a 180 turn. The initial part of the application of take-off power is then made against the aircraft brakes to make a check of engine parameters. This procedure can take up to 4 minutes before the aircraft actually commences its straight line acceleration to takeoff..

It is also not possible for aircraft to assemble close together at the beginning of the runway because of the possible risk of damage to other aircraft from the engine exhaust when take-off power is applied. There is therefore a delay before each aircraft can reach the point at which its takeoff precedure can be initiated.

According to the present invention there is provided an airfield including at least one main runway having a longitudinal axis for aircraft landing and taking off, and at, or adjacent, one or both ends of the runway, at least one additional take-off path curved or angled out of the longitudinal axis of the main runway and joining the main runway substantially tangentially to said axis.

Preferably, at least one of said additional takeoff paths is disposed on each side of the runway. Alternatively a plurality of take-off paths can be disposed on one, or even both, of the sides of the main runway. The particuiar configuration adopted will depend principally on the configuration of the airfield, when the invention is applied to an existing airfield, or to the land available when a new airfield is being constructed, or to the capacity required.

The present invention also provides a method of controlling aircraft traffic utilising such an arfieId, in which aircraft are positioned for takeoff on the take-off paths and are then authorised to take-off successively by accelerating along said take-off paths onto the main runway in a predetermined sequence which may be determined by the weight of the aircraft taking-off.. Because of the turbulence caused by large aircraft, a minimum time interval of 2 minutes must elapse before a substantially lighter aircraft can follow, and therefore to reduce this interval to a minimum it is preferred that the lighter aircraft should take-off first. Where all the aircraft are of substantially the same size, the sequence may be determined by, for example, the method by which the aircraft are moved to the takeoff paths from the loading terminals.

A preferred embodiment of the invention will now be described by way of example only, with reference to the accompanying informal drawings in which: Figure 1 shows, in schematic form, the start of an air field runway incorporating four curved takeoff paths, and Figure 2 shows the embodiment of Figure 1 superimposed on a plan of an existing airport, in this case, Gatwick airport.

Referring now to Figure 1 there is shown the first 900 metres of the approach onto a main runway 1. The main runway 1 includes a straight take-off portion 2 aligned with the longitudinal axis 3 of the main runway. Two curved take-off paths 4 and 5 respectively are located on one side of the longitudinal axis of the runway 1 and two further curved takeoff paths 6 and 7 are located on the other side of the longitudinal axis 3. Since the four take-off paths do not have to take the loads imposed by landing aircraft, they do not necessarily need to be constructed to the standard required for main runways and can therefore be relatively cheap to construct.

Although shown as generally exponential curves, whose maximum anguiar displace ment occurs at the end further from the main runway, at which the lowest speeds will oc cur, it will be appreciated that the precise shape of the paths will be determined by practical considerations. It is envisaged that the paths may be basically straight but in dined at an angle to the longitudinal axis of the main runway but they may also be in a series of short straight stretches gradually merging generally tangentially with the main runway as in the curved paths shown in figure 1.

in use, each aircraft will taxi to the particu lar take-off path authorised by air traffice control. Each aircraft when authorised to take off may apply maximum take-off power at the beginning of the curved path so that by the time the main runway is reached the aircraft has gained considerable speed already. Aircraft in the other take-off paths may follow in a predetermined sequence with their takeoff intervals much closer than withathe conventional system because of this speed build-up.

With a lay out of multiple take-off paths in accordance with the present embodiment up to five aircraft can be preparing simultaneously for takeoff on their own individual paths without having to worry about the proximity of other aircraft. With this arrangement, it is envisaged that a maximum space between aircraft of 1 minute or even less would be feasible without reducing existing safety standards. In this way, the maximum capacity of an airfield could be increased by up to 100%.

Referring now to Figure 2, a layout of curved take-off paths as shown in Figure 1 is shown incorporated on a plan of an existing airport, namely Gatwick. The existing concrete aprons and runways are shown in a single crosshatching and the additional concrete are necessary to provide the five paths shown in Figure 1 is shown in a crossed hatch arrangement. It can be seen that the additional area required falls well within the perimeter of the existing airport layout. It also does not require the aircraft to travel further from the existing terminal buildings which are shown in block form, reference T, although it will be appreciated that the precise effect will depend on the particular layout of the airport to which the invention is applied.

Claims (5)

1. An airfield including at least one main runway having a longitudinal axis for aircraft landing and taking off, and at, or adjacent, one or both ends of the runway at least one additional take-off path curved or angled out of the longitudinal axis of the main runway and joining the main runway substantially tangentially to said axis.

2. An airfield as claimed in claim 1 wherein at least one of said additional take-off paths is disposed on each side of the main runway at, or adjacent, one or both ends thereof.

3. An arifield as claimed in claim 1 or 2 wherein a plurality of said additional take-off paths are disposed on one or both sides of the main runway.

4. A method of controlling aircraft traffic utilising an airfield as claimed in claims 1, 2 or 3, in which aircraft are positioned for takeoff on the main runway and at least one of said additional take-off paths and are then authorised to take off successively by accelerating along the take paths onto the main runway for take-off in a predetermined sequence.

5. An airfield substantially as described herein with reference to and as illustrated in the accompanying drawings.