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BlueDiamond
17th Dec 2001, 06:55
I've never flown into Hong Kong but I have seen many photos of the approach and am curious about that checkerboard and its purpose.

So, what is it for? What does it do?

QUIFFI
17th Dec 2001, 14:39
Because of the curved approach into Hong Kong, ie no straight in ILS, you had to fly the IGS. This was the same as an ILS but pointed you towards a big hill. The required visual reference was the checkerboaord. Once seen you converted to a visual approach. Put the wingtip on the football field and look right! The running rabbit was curved around to give you a run in to the threshold. You could walk up to the checkerboard and watch the aircraft making the approach. A bit sad but good fun!

scanscanscan
17th Dec 2001, 16:27
Quiffi.. You land on the runway, not the checkerboard and it was the runway threshold that my company wanted for visual reference at minima, not the checkerboard.
I did the IGS (767 and L1011) by flying down the igs to minima,and at the 100 above call, visual scaning right, 50 degreeish, if I saw the threshold and idented the lead in lights and sequence flashers (rabbit) I called land at the nhp decide call ( at the 100 above call I started mentally counting to five
(quite quickly!) whilst scanning for the runway, if I got to five and no call decide and no visual reference I was back on the gauges and the altimiter minima to action the goaround.
The nhp and FE had a bad habit of dieing at this point in the simulator or both being instructed to miss the decide call) disconnected the Auto pilot and ats and banked right 30 degrees initially and then reduced bank to maintained these lights between my knees and followed the lead in lights and rabbit to the threshold.
I would ask the nhp to continuously called the ROD and airspeed,( it kept us all in the loop and I felt helped my limited flying ability) then the standard manual landing height calls.
At the decide call (minima) the A/P and A/Throttle were disconnected and the f/d switched off only if the captain had responded Land.

If at Decide call, (or at minima if the call was missed) he did not have the required visual reference he responded Goaround and the automatics were retained and it was done on auto pilot.
The banked turn in, started at minima as per the approach plate, and this worked for us. For my sins I did this approach from 1975 until the new airport opened and I never used the checker board!!
On the igs I was either on instruments or visual with the threshold and tracking the lights and the rabbit.
I did not use the football field for navigation either but always asked and got precision radar monitoring for my approaches, and why not? If you are no good you need all the back up you can get!!
At one time there was a rumour of some false localiser captures , followed by g/s capture, not nice.
I was told that a few L1011 and 747 did in fact fly around the checkerboard, at minima, clockwise!
And they still landed on rw13.
Cheers,

[ 17 December 2001: Message edited by: scanscanscan ]

BlueDiamond
17th Dec 2001, 18:39
Thanks Quiffi and Scans ... that certainly answered the question but I would now like to ask another. Was there only the one approach to this airport regardless of wind direction or was the other end of that runway an easier approach?

M.Mouse
17th Dec 2001, 19:21
scanscanscan

Reading your interesting post made me realise how much more straightforward a monitored approach is when faced with flying down to minima.

There that should liven this thread up a little! :D :D :D :D

Flap 5
18th Dec 2001, 21:38
... and then there was the visual step down to runway 13. This took you to the south of Lantau Island and provided an excellent view of Hong Kong - especially at night. Cathay did not do visual step downs at night as someone had cocked it up at some time and they were not allowed. But Dragonair pilots were much more experienced with approaches to Kai Tak and were allowed to do night visual stepdowns. ;)

Flap 5
18th Dec 2001, 21:42
by the way the checkerboard was very useful when doing a visual stepdown. But basically as long as you were at 1500 feet over Stonecutters Island (it was an island then), and starting to turn right, you were in the ball park.

scanscanscan
19th Dec 2001, 01:22
Right on flaps 5..I heard that one also, training captain required trainee to do a night visual, and then they both got confused by the sea of lights and it all went a bit wrong.
Do not know who put the most pressure on whom!!

411A
19th Dec 2001, 07:56
The CC NDB approach was interesting, especially at night in the driving rain. Think my Chinese F/O's eyes went...round.