AU608435B2

AU608435B2 - Novel air pilot aid

Info

Publication number: AU608435B2
Application number: AU33936/89A
Authority: AU
Inventors: Colin Henry Peck
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-05-02
Filing date: 1989-05-02
Publication date: 1991-03-28
Anticipated expiration: 2009-05-02
Also published as: AU3393689A

Description

608435 This doc~Unetnt contains thec amendments made under- Section 49 and is correct for printing.

COMMONWEALTH OF AUSTRALIA PATENTS ACT,1952 COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: NOVEL AIR PILOT AID The Following statement is a full, description of this invention, including the best method of performing it known to me: Air Pilot Aid This invention relates to a novel air pilot aid for use in the landing of aircraft.

During the approach to land, a pilot of a large aircraft must fly a very precise approach slope (ideally 30 to the horizontal). An accuracy of plus or minus 0.25Q is required. Currently, the systems in use to assist the pilot in achieving the ideal slope are:a) Visual Approach Slope Indicating System (VASIS), wherein a system of lights is installed beside the runway near the touchdown point. The lights are designed to give the pilot an indication of whether he is high, low, oi on the ideal slope; and b) Instrument Landing System (ILS) wherein a system of radio transmitters is installed on the ground near the runway. The aircraft is fitted with special receivers and the data from the 4 20, ground is translated into indications on the pilot's instrument panel.

The invention is not intended to replace either of the above systems, although in many circumstances, if available, it would be used in preference to them. Rather, it is intended to supplement the above systems, especially to provide the pilot with guidance at runways where VASIS/ILS ground equipment has not been -2installed, is unserviceable, or is unavailable for some other reason.

Some of the disadvantages of the systems currently being used are:a) both systems require the installation of expensive ground equipment which must be kept serviceable, aligned and tested, ±0 b) they do not provide guidance if the touch-down point has to be displaced (eg, for runway works, temporary obstacles, etc.), c) they are not available at all runways, d) USA, UK, France and Australia have each developed different VASIS's, thus an international pilot has to be trained to interpret each system, tit 4 e) interpretation of VASIS indications is not simple, 22b f) the pilot of a large aircraft (eg Boeing 747) must use a different touch-down aiming point to that used on a smaller aircraft, and the pilot must therefore make adjustments to the indications provided by a VASIS sited for a smaller aircraft, g) although the ILS provides very precise qlope guidance data, it requires the pilot to devote a majority of his attention to his -3i I-a i instrument panel. There are circumstances where this is undesirable and unsafe.

The purpose of the invention is to provide pilots with a supplementary approach slope guidance system, which will be available when existing systems are unavailable, improve safety by increasing redundancy, and under certain circumstances, have advantages over existing systems.

The invention will now be described with reference to the following figures and to preferred embodiments. However it is not intended that the invention be limited to thk figures or preferred embodiments described herein.

The invention comprises an installation in an aircraft of an optical system that allows the projection of a graticule image (6) from a graticule image projector via mirror onto an angled glass surface located in front of the pilot The angled S' glass surface reflects the projected graticule image back to the pilot's eyes The optical system is interfaced with the aircraft's gyro system so that the graticule image gives the pilot a true reference to the horizontal, regardless of the aircraft's nose attitude (Figure It should be understood that while flying the 30 slope, the aircraft's nose up attitude will change as the speed and configuration of the aircraft change.

-4- The optical system may be similar to those ,ised in gunsights and other head up displays (HUD). The optical aystem allows the graticule to be focused at infinity, so that the pilot's eyes can focus on both the reflected graticule and the aiming point on the ground and will also allow reasonable movement of the pilot's head without moving outside the range of the projected graticule image.

In a preferred embodiment of the invention the graticule image embodies appropriate marks to allow assessment of the desired flight path of the aircraft during the approach to landing.

In an other preferred embodiment of the invention the graticule would also include a mark giving the true horizon. During highaltitude operations, where it is not possible to visually assess the true horizontal, this mark would be useful to the pilot in judging whether a danger* eg. a storm cloud or another aircraft, was above, level with or below the pilot's flight path, To use the system, the pilot would fly the aircraft so that the mark in the graticule representing 3 0 -down remains on the touchdown aimning point on the ground While ever this is achieved the aircraft must be on the desired approach. slope. The system can also be used during phases other than approach-to-land, particularly at high altitudes, where the pilot observes a possible hazard and can thus more accurately determine the relative position of the hazard to the flight path of the aircraft 'L~q b observation through the graticule image.

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It is intended that the system would be installed in aircraft that required a precise approach slope, that is, most current airliners and other large aircraft. The system would supplement existing approach slope aids in that it would be available for use by the pilot when current ground installations were unavailable. In addition, its ease of interpretation would make it preferable to existing aids in many circumstances. A bonus is that the system could allow more accurate assessment of the relative altitudes of visually perceived dangers during high-altitude flight.

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Claims

1. An approach slope guidance system for installation in an aircraft comprising an optical system that allows the projection of a graticule image onto an angled glass surface located in front of a pilot of the aircraft, said angled glass surface reflecting the projected graticule image back to the pilot's eyes, and wherein the said optical system is interfaced with the gyro system of the aircraft such that the graticule image gives the pilot a true referene to the horizontal regardless of the aircraft's nose attitude.

2. An approach slope guidance system according to claim 1, wherein the graticule image embodies appropriate marks to allow 15 assessment of the desired flight path of the aircraft during i approach to landing.

3. An approach slope guidance system according to claim 1 or 2, wherein the graticule image includes a mark which indicates the true horizon.

4. An approach slope guidance system according to any one of claims 1 to 3, when used as a supplementary approach slope guidance system.

A method of use of the approach slope guidance system according to any one of claims 1 to 3, wherein the flight of the 4r ,aircraft can be adjusted by the pilot so that the appropriate part i of the graticule image remains on the desired touchdown point on the ground.

6. A method according to claim 5, when used as a supplement to or in place of existing approach slope guidance systems.

7. An approach slope guidance system according to any one of claims 1 to 3, when used in the assessment of the relative a r altitudes of visually perceived dangers during high altitude a 1 t IQ I flight. a i a. Ii S

8. An approach slope guidance system according to any one of claims 1 to 3, when used during phases of flight other than on approach-to-land, particularly at high altitudes, wherein the 4 pilot observes a possible hazard through the graticule image and more accurately determines whether such hazard is above, level with or below che flight path of the aircraft. 0,

9. An approach slope guidance system according to any one of claims 1 to 3, substantially as herein described with reference to any one of the foregoing figures. DATED this 26th day of December, 1990 Colin Henry Peck.