Questions for UK ATC from a new CPL

[buttline]

Hi all,

I'm sitting my JAA Air Law ATPL exam this week. The course has raised more questions than answers!

I'm curious about...

Why is there no Class C airspace in the UK?

What is Automatic Dependent Surveillance?

Why is the U.S. more oriented towards vectoring whereas the UK seems to like procedures for arrivals and departures?

Please confirm that entry to the hold is based on 5 degrees of Magnetic heading. I've seen references to holding based on Track in the feedback questions of several high quality flight schools.

This is the basic big picture I've managed to glean from the course, please correct where I'm off track! :-)
Aerodrome Control is for taxiing, landing and taking off.
Approach Control handle the SIDs and STARs phases of the flight.
Area Control handle the en-route phase.

I'd be grateful if anyone can point me to a useful text for pilots on ATC - the course has us just memorising heaps of helpful facts such as "the callsign is 30cm high on the tail of a heavy and memorising the titles and numbers of the 18 Annexes to Chicago". I know you guys have a 3 year school, so I guess I can't compain too much - I just hope your course was more useful for our sake! :)

[zonoma]

No idea about the first two, other than there's probably no requirement for Class C over here due to the much less amount of VFR we have compared to the States. (either that or we are just far too restrictive!!)

The vectoring/procedures bit is just a guess, but probably due to our airports not being multi runway multi arrival/departure, only LHR can have independant ops, but just ONE landing and ONE departing at any time.

Holds are aligned magnetically, and recently several of ours have just re-aligned due to the slight change in variation.

Your basic picture is correct, with an addition that Approach also deal with transits through the zone to add separation from the deps/arr.

Our college course in the UK lasts for 18 months for area control, which includes some 'hands on' experience, and I think 12 months for approach. In NATS you have to do the approach radar course even if you are to work in the tower. After this you get posted to a unit for further, sector specific training, which, once you start, takes about a year to complete. Its one of those 'when you're ready, we'll get you checked out', presuming you are actually doing well enough!!!!

Hpoe this helps, and good luck!!

[Bern Oulli]

ADS - Check this site (I've only just found it myself)

http://www.ads-b.com/content/index.htm

[HEATHROW DIRECTOR]

Probably one good reason for the different procedures in the UK and the USA is space. They have hundreds of miles to play with and can start streaming - and speed control - at very considerable distances from destination. Over here in many cases we only have a few dozen miles to play with so radar-controlled streaming is not possible as a regular procedure.

[eyeinthesky]

Reference vectoring: I think it would be fair to say that at airports where they have a radar available they much prefer to use radar vectors for the approach rather than a procedural service. This means a quicker approach in many cases and you can handle more aircraft at a time. If you consider the procedure, only one aircraft can be in each segment at each time (outbound, base turn, inbound). With radar vectoring you can have them both sides downwind or base and you can put them under speed control etc. Far more efficient and usually shorter for a/c and ATC alike.

The only time you might get a lot of procedural approaches at a radar unit is if the radar is off or due training requirements (pilots, not controllers!). An example of this would be Bournemouth, where IFR arrivals are usually put on radar vectors while training flights fly the procedure in between. Even there the procedure will be modified based upon what they see on radar(e.g. "Cleared for the procedure, but maintain 3000ft until advised".)

Entry to the hold: Hold axes are based upon their magnetic TRACK. Entry to them is based upon your magnetic track (remember the 70 degree line dividing up Direct/Offset/Parallel?), but I suppose unless it is blowing a gale it will be fairly close to your heading as well.

[Spitoon]

FWIW on the Class C thing - when the new airspace classes came in I recall being told by a CAA man that although the names would change, it was being fudged so that the way that aircraft were ahndled would stay the same.

Traditionally we've not gone in for controlled VFR in the UK (although it may not seem like it if you fly VFR through some Class D airspace!) so I guess there was no need for Class C. I don't think it's any more involved than that.

[buttline]

Eyeinthesky,

Are you certain entry to the hold is based on TRACK and not HEADING? My instructor and the Oxford/Jeppesen notes (Air Law page 7-44) both say it's HEADING but I've also seen feedback questions based on TRACK.

I guess in the real world it doesn't matter too much as drift is probably never that bad but for the exam, I have to know for sure.


Many thanks.

[eyeinthesky]

I wouldn't want to argue with knowledgable ground instructors, but let's take this further.

Consider you are to enter a hold which has a magnetic axis of 270 degrees, turning left at the fix.

You are approaching the fix from the WNW. Your present position is North of the extended axis of the hold, and your track to the fix is 110 degrees. However, due to a strong northerly wind your heading is, say, 085 degrees.

Your TRACK will dictate an offset entry (30 degrees off the reciprocal and then a left turn to intercept the inbound axis), but your HEADING will dictate a parallel entry (Over the fix and reciprocal track until right turn back to the fix).

You could get yourself in a real mess there when you turn right instead of left.

It is a while since I did the groundschool for my IR, so I might have it all wrong, in which case I shall consider myself humiliated!:confused: :D

[HEATHROW DIRECTOR]

buttline wrote: "I guess in the real world it doesn't matter too much as drift is probably never that bad "

Just to let you know that you're in for some real fun when you start flying!

[buttline]

Heathrow Director,

I have 200 hours in helicopters and yes, they are great fun - thank you. Helicopters of course suffer from drift quite badly being so slow, but then we're not accustomed to taking up the hold anyway. I was guessing, apparently erroneously, that drift would be less significant in a fast jet.

Any chance of an answer to the question? ;)

[Dances with Boffins]

The official [exam] answer is HEADING [magnetic]. There are many opinions as to the validity of this rule, depending on the experience/background of the opinions holder. I can't lay my hands on the ICAO Document to get the actual reference, but my trusty RAF Flight Information Handbook has it in chapter and verse on pages 46 and 47. No use to you in Florida, sorry.
:cool: