LSZH go around this morning - 03/03/04

[piton]

Hello all,

With a scant 5 miles separation this morning (behind an A340) we were instructed to go around at LSZH. (EZ 737-700) Was anyone here working?

Why was that too close - eg to compare with LGW where we regularly come in at 3 miles separation - admittedly not necc behind a heavy.

But 5 miles would normally seem sufficient - we were warned for wake but didn't have any trouble. Just curious - especially as I am doing the same flight tomorrow! (5103). We had complied with speed restrictions on approach and gained maybe a half mile in the final segment - is the ability of the previous to vacate a factor?

We were at 1000+ft AGL at the time when instructed to carry out the MISAP - i.e. it was not a case of a/c still on runway at the last minute.

Would be glad to hear from any ZRH controllers how to prevent a reoccurance.

[ZUE]

I was the instructor giving OJT to a student when your go-around took place. He only had 4.8nm to the preceding A340, the requirement is 5.0nm (medium behind heavy). You were thus repositioned for safety reasons.

We do sincerely apologise for the inconvenience but even us ATC's get it wrong now and again. :O

[Geffen]

Too bad but often when training it is necessary to teach trainee positive control to ensure separation, especially when it is Vortex. On the other hand we often slow the aircraft at the back down(if traffic situation allows) to keep the vortex spacing.

[Gonzo]

Or we just send it round anyway, don't we Geffen? :ok:

[Geffen]

If you send it around you've at least got to let them see the runway, and snatch it away at the last minute! :)

[piton]

Thanks ZUE for the info - sure, we all have to learn sometime and there is no substitute for OJT. No problem - made a good story in the crew room later! No fog/snow in ZRH and still a misap!


Just a thought - operated the same flight this am and similar to yesterday we told by approach to maintain 160 to 4dme then as soon as changed to TWR - reduce min appr speed - eg from 6 dme or so. As the 737-700 doesn't slow that quickly it probably does cause that 0.2 mile creep - especially if as you try to check in some one else is transmitting - murphy's law and all that. Why does appr stress maintain 160 until 4 when training is going on - to keep up the pressure or is it just coincidence? 160 to 6 might be more useful Luckily today we were behind another medium so 4 miles was okay!!

[055166k]

I congratulate Zurich on their equipment, nothing I use could differentiate a 0.2 mile separation infringement. I think our supervisor has one to catch us out.....but my range lines only work to whole miles [ green with envy!!!]

[normally right blank]

"Why does appr stress maintain 160 until 4 when training is going on - to keep up the pressure or is it just coincidence?"

You're right! To keep the pressure and see if this student is ready for validation - and you are happy to work beside him/her.