| 摘要 |
<p>An aircraft landing approach system in which the approach radar (1) has accurate ranging and angle tracking facilities and a platform recognition facility which can identify an active transponder (7) and identify a landing facility e.g. oil rig platform (5) in the absence or failure of a transponder. For fixed wing aircraft an active transponder returns aircraft location information and for helicopter platform operation a passive reflector system may also return helicopter position information. In operation of the system a course is set, preferably from the point of platform recognition and location, which misses the platform and from which visual approach is effected.</p> |
