ATC UK question

[MEL-able]

Why is there in the UK over a small area (London, Birmingham, Manchester)such a difference in transition altitude?

London 6000
Birmingham 5000 (as I recall from memory)
Manchester 4000

Why not make it simple for everyone and just draw 1 line at 6000 ft overall to clear the difference....

Can anyone explain?

p.s.
second question..

Why is England the only place in the WORLD where you don't get a "cleared for the ILS", but either report Loc or a conditional clearence.
If you get the final vector, you normally go for the full approach. If in 1 case you cannot descent with the glide, thence ATC can give you "intercept loc"...

Again...try to keep it simple for everyone with 1 standard..

Again, does anyone have a good explanation?

Thanx
MEL-able

[HEATHROW DIRECTOR]

I cannot answer Q.1.

Q.2 One reason why (at Heathrow at least) we do not clear pilots for the ILS is that in the past some pilots so cleared have descended to dangerously low altitudes many miles from touchdown. Maybe they didn't appreciate that there is other traffic under the ILS approaches - helicopters, light aircraft, traffic into other airports, etc., and the only satisfactory way to sort this is to get them to establish on the loc while ATC still has full altitude control. Once thus established they are told to descend on the ILS. It may be seen as a non-standard procedure but it's pretty safe.. "Belt and braces" we call it!

[Yellow Snow]

Was told a while back on a fam flight that it was to do with terrain clearances!! In the states the transition alt is 17 or 18,000 feet(one or the other) and that's based on the height of Mt Mckinley (apologies for poor spelling) the highest object over there.
Then again it could've been rubbish :)

[NextLeftAndCallGround]

Q1 - Dunno but I hear there is a review going on to try and harmonise the different TAs in the UK ... but no doubt they can't agree whose to use!

Q2 - I believe it stems from a number of incidents a few years back when the aircraft was put on a closing heading at, say, 4000ft when the published ILS procedure started at 2500ft. I think several aircraft took a clearance for the ILS approach as clearance to descend to 2500 immediately. As HD says, it's not uncommon to have traffic going under the approaches (often VFR so it doesn't just apply to LHR) - not a problem if the controller has calculated that the ILS traffic will intercept the glidepath well past the transit traffic at its last cleared level but a bit of a shock for all concerned if the ILS aircraft drops earlier!

On the other hand I might be completely wrong. Why should there be any logic to aviation?

[Spoonbill]

Q1 - This has been under discussion for as long as I can rememeber, and whilst 6000ft would be eminently sensible, (I don't think that there's anything that high in the UK near any of our airports is there?), like everything else, actual decision making in the UK is a tortuous process which utilises
the logic of a tortoise and an ostrich.
Q2 - I refer to the answers already given m'lord. :)

[NudgingSteel]

Would a higher transition level not make things easier for the crews on initial climb? Presumably they have to set 1013 once cleared above the TL; modern jets are up at 4-6000' in no time, hence it's yet another thing to do in the busy first few minutes?

Any crews, please feel free to confirm or deny.