Kai tak IGS

[RUDAS]

Hi.
Since kai tak was a bit before my time,i never got to understand how their IGS worked.Have flown visual app's into Kai Tak on the 777 Sim at HK,but not the IGS. Can anyone explain how the IGS worked and if there are any other in use around the world?

Thanks:ok:

[TopBunk]

Rudas

The IGS comprised of the elements of an ILS, ie a Localiser and a glideslope.

In that sense they worked exactly like an ILS in terms of instrument depiction BUT the localiser was not at the far end of the runway as with a normal ILS localiser but offset by some 47 degrees as I recall.

The result was that the IGS got you to precisely to a point from which a manual/visual transition could be made to a landing (hopefully!). The turn to final could be 'interesting' depending on the wind (direction often a strong tail becoming cross from teh right on rollout), the turbulence due terrain, the visibility etc, made all the harder at the end of a 13 hour flight in a 747 with a Vref of 150kts in a typhoon when you haven't done a landing for 4 weeks!

The point at which you broke off was at 2nm dme, 600ft aal - the dme was set of give distance to threshold I think.

In effect it is just an offset localiser approach (albeit more offset) than a good many around the world.

[ShyTorque]

Yes, it was really just an ILS set on the rocks. The "aiming point" or rather the "point to miss" was known as the "Chequer board". It was painted on the hillside in dayglo and white. On seeing that, it was time to look to starboard and think about the visual approach. It had to be done this way because of the alignment of the runway and the hills to the north.

Forgot to mention, there was a series of very bright white lights set in a curve, some on posts, some on high-rise buildings, provided to help you find the runway.

I was based out there for 4 years and NEVER heard the METAR go below minima, irrespective of the real "actual" which was interesting.....:suspect:

If you PM me with an email address I could send you a scan of the plate, which I kept for posterity and to scare my kids.

[TopBunk]

Shytorque

It was the glideslope aerial that was on the checker board hill, the localiser lower down at the end of a sports field, I think. I remember spending some time on the top of the checker board markings (not in the park!, having found a hold to climb through) watching approaches onto rwy13 from the IGS.

The technique of the Cathay locals seemed to be to fly a little to the north (left) of the localiser to give themselves a little extra room for the turn onto finals, but I'm sure we've all seen some of the clips where some pilots didn't quite get it right;)

[ShyTorque]

TB,

You may well be correct, I never looked that closely. If the weather was too bad, we used to ignore the IGS, let down over the sea and come in very low level up the harbour, dodging ships using the radar.... ;)

[767bill]

Hi,

Just out of interest what has happened to Kai Tak, what happens now at the airport terminal (has it been demolished) and on the runway now that there is the new airport?

Was interested to read about the approach system. As a teenager my father worked in HK so I had the opportunity to witness (from the right hand side of the aircraft) the scary last miunte turns. Incidentally, I heard of a least one occasion of a 747 touching down only to takeoff again due to not enough runway to stop, no doubt with the harbour looming ever closer...

767bill

[GlueBall]

Photo (http://www.airliners.net/open.file/554126/L/)

[828a]

The pilot who did not enjoy threading the needle on Kai Tak Rw13 was in the wrong business. It seemed to me there were three ways to fly this approach. If the weather was marginal the localiser had to be accurately tracked to minima. However if fully visual one could tuck the left wing up against the chequer board and effectively "tame" the approach by reducing the amount of turn. The third way was to stay inside the localiser [ on the right hand side ] and pick the point to lay on the bank This required some close attenion as delaying the point required an ever increasing bank angle. The sweet taste of success came with rolling the wings level and finding yourself looking straight down the centre line with the speed nailed on the bug. No autopilots or autothrottles needed for this little piece of pure personal pleasure . Rw13 Kai Tak is gone forever but for some the memory and affection remains.

[Cornish Jack]

It is possible to experience the procedure a la B744 with the original version of a well modelled PC Sim program.
Danny's advertising rules don't allow the full details but a Dogpile or Google search should show it.

[ant1]

I've read that it was commonly accepted to fly slightly left of the IGS course (closer to the hills) in order to buy some extra space for the right turn to final.

There is also this thread (among many others) on pprune: Tales from Kai Tak (http://www.pprune.org/forums/showthread.php?threadid=132974&highlight=kai+and+tak+and+time)

And this story that I enjoyed reading in Times Asia Magazine: A Plane Spotter's Lament (http://www.time.com/time/asia/magazine/article/0,13673,501030728-465841,00.html)

It won't ever be the same :sad:

[411A]

Some years before there even was an IGS (and for several years after as well) there was the CC NDB approach to Runway 13...via Stonecutters and RW NDB's

An interesting ride across the harbour...especially at night, in the heavy rain...:ooh: :ooh:

Afterwords, time to retire to the bar and ....'make mine a double'.

Hmmm, come to think of it, 'reverse thrust' was even better'.
Sadly, the younger guys will never know the pleasure.

[Denzil]

Great picture Glueball, though what a really great shame that Kai Tak couldn't be preserved as it's one of the great airports in aviation history. I believe that there is a possibilty of the ATC tower being kept though.

[828a]

411A The CC360 NDB approach to Rw13 was even more fun than the sterile IGS that replaced it. Better still was an unrestricted visual from the north that could be tracked at 1000 ft around the southern side of Hongkong island and up the western harbour to Scone Cutters for a close in turn onto Rw13. Start it at 1000ft level VNE with the four thrust levers back on the stops and ease the speed off in a long sweeping arc that ended at Stone Cutters with the gear and flaps down the thrust up and the speed on the bug. Nothing to do now except pay close attention to the descent rate and watch the centre line as the turn moves it across. Does that sound familiar ???? . Gives me pleasure just to type it out.

[411A]

Completed several of those in the 'ole 707, 828a, and as you say... delightful.