IMC/ASR question [Archive]

Pianorak

17th Feb 2005, 17:08

Flying from Clacton to Compton Abbas via LAM, BNN, CPT and Chilbolton apparently requires i.a. the Yarmouth regional pressure setting. (IMC Q & A Simplifier, Mathews/Pratt, 2000 Edition).
I’d have thought Chatham, Portland and Cotswold would suffice, but I suspect I am wrong. :{

Chilli Monster

17th Feb 2005, 19:57

Half wrong ;)

Clacton - BNN - LAM - CPT is mainly under the London TMA. London QNH therefore should be used - NEVER a regional pressure setting.

Pianorak

17th Feb 2005, 21:11

Thanks Chilli Monster – But do you agree that Yarmouth regional pressure setting is completely irrelevant? And yes, I should have mentioned the London QNH.

Chilli Monster

17th Feb 2005, 21:22

Yes - Yarmouth is total tosh :)

IO540

18th Feb 2005, 09:12

Where would one get "London QNH" from? The Heathrow or Gatwick ATIS?

DubTrub

18th Feb 2005, 09:15

London Info, since that is what they are there for. 124.6

RodgerF

18th Feb 2005, 09:28

Whole range of sources.

On that route in IMC one could consider RIS from Southend or possibly Essex Radar and then use the Southend or Stansted QNH.

London Volmet Main or South will have pressure settings as well.

tmmorris

18th Feb 2005, 12:14

I find usually that anyone I talk to round there can tell me - though I did once request it from Brize as I was approaching Compton and they seemed surprised (but came back with it after 20 secs or so).

Very important point, though: are there stats on how many CAS incursions are caused by this mistake?

Tim

Chilli Monster

18th Feb 2005, 14:16

Where would one get "London QNH" from? The Heathrow or Gatwick ATIS?

Interesting to note that nobody has stated the most obvious place, especially when flying with reference to VOR's

Don't we ident anymore ;)

Have a listen to either 'BIG', 'BNN', 'LAM' or 'OCK' next time you're in the area.

Evil J

19th Feb 2005, 13:20

tmmorris:- try looking at www.flyontrack.co.uk this has up to date infringement stats month by month as presented to the Airspace Infringement Working Group (the CAA response to the On-Track report).

As an operational controller I would certainly say that it is a VERY common mistake for people flying underneath CAS to be flying on a RPS-especially if they are talking to one of the many nearby military units near where I work-ofcourse those without mode C displayed risk being collected by a 737...