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Old 10th Nov 2013, 09:22
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Davita
 
Join Date: May 2013
Location: Bali, Indonesia
Age: 86
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The worst offset ILS I encountered in my career was the old Hong Kong airport at Kai Tak...... r'way 13
Here is an interesting wikipedia of that approach using offset ILS.

"The landing approach using runway 13 at Kai Tak was spectacular and world-famous. To land on runway 13, an aircraft first took a descent heading northeast. The aircraft would pass over the crowded harbour, and then the very densely populated areas of Western Kowloon. This leg of the approach was guided by an IGS (Instrument Guidance System, a modified ILS) after 1974.
Upon reaching a small hill marked with a huge "aviation orange" and white checkerboard used as a visual reference point on the final approach (in addition to the middle marker on the Instrument Guidance System), the pilot needed to make a 47° visual right turn to line up with the runway and complete the final leg. The aircraft would be just two nautical miles (3.7 km) from touchdown, at a height of less than 1,000 feet (300 m) when the turn was made. Typically the plane would enter the final right turn at a height of about 650 feet (200 m) and exit it at a height of 140 feet (43 m) to line up with the runway. This manoeuver has become widely known in the piloting community as the "Hong Kong Turn" or "Checkerboard Turn". Amongst passengers it became known as the "Kai Tak Heart Attack".[18]
Landing the runway 13 approach was already difficult with normal crosswinds since even if the wind direction was constant, it was changing relative to the aircraft during the 47° visual right turn. The landing would become even more challenging when crosswinds from the northeast were strong and gusty during typhoons. The mountain range northeast of the airport also makes wind vary greatly in both speed and direction. From a spectator's point of view, watching large Boeing 747s banking at low altitudes and taking big crab angles during their final approaches was quite thrilling. Despite the difficulty, the runway 13 approach was nonetheless used most of the time due to the prevailing wind direction in Hong Kong.
Due to the turn in final approach, ILS was not available for runway 13 and landings had to follow a visual approach. This made the runway unusable in low visibility conditions."

We used to do this on B707 in typhoon conditions but stopped when big fanjets were used as the fan could not handle the shifting winds.
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