Estimate for airfield boundary

[elcol]

Can anyone help with this ATPL A comms theory question?
"How much notice must a pilot give ATC when passing his estimate for the airfield boundary?"
I've been through Annex 10 Vol 2, Doc 4444 and the Manual of Air Traffic.
All I've found so far is that the controller needs to give 5 minutes notice to the next ATCU.
Any input wold be gratefully received particularly if you can quote a reference.

[HEATHROW DIRECTOR]

I wonder who dreams up this stuff? What does the pilot say: "I hereby give notice that in 5 minutes I will pass my estimate for the airfield boundary"?

And what does "the controller needs to give 5 minutes notice to the next ATCU."?

It doesn't happen in real life, unless things have drastically changed.

[blissbak]

I'm with HD, and what's the definition of airfield boundary?

[ZOOKER]

I've never encountered this in 30 years of Tower, Approach or Area control.
Could it be something to do with FIR boundary estimates, or 'Approval Requests', which are still defined in MATS Pt.1?

[OhNoCB]

If oyu take airfield boundary to mean ATZ then the rule is 15nm or 5 mins. This is what was in my head and I just checked it against one of my old theory books (so disclaimer about it still being valid etc) however I have not yet known it to be observed in practice and 'as soon as practicable' tends to suffice.

[elcol]

Thanks for your input chaps. OhNoCB, can't find those numbers in any current official reference material but that's not to say it's the answer their looking for!

[spekesoftly]

...... can't find those numbers in any current official reference material ..... See UK AIP GEN 3.3-5 Air Traffic Services, Para 3.7.3.1

http://www.ead.eurocontrol.int/eadbasic/pamslight-EB6435EF35F8C1D04693EC6860E21865/7FE5QZZF3FXUS/EN/AIP/GEN/EG_GEN_3_3_en_2016-02-04.pdf