Getting hold of regional QNH

[Pilot16]

Hi, I was wondering how I can get hold of the regional QNH (London/Chatham QNH) prior to flight for flight planning purposes?

I searched all forms and dial up services I know how to get Aerodrome QNH, but what if I am after London or Chatham QNH?

Thanks

[EKKL]

Does your Instructor not know?

[DB6]

You can normally get it from the tower as you taxi or by phone beforehand, however if you only have A/G they might not have it. The military have MOMIDS, an intranet which has forecast QNHs amongst other things, so try calling your nearest military met office if all else fails.

[Pilot16]

Well I havent flown for a long time. Thanks for the replies. Yes I know, you cant get it from the A/G station on my airfield. It seems like getting the regional QNH beforehand is tougher than i thought.

Cant the MET Office publish it somewhere or something

[expedite_climb]

Difficult to publish anywhere that it may be reproduced in paper form as it is updated every hour !

Out of interest - why do you need to know it before a flight ?

[Pilot16]

oh that must be why i suppose!

I was just interested...say for TAS calculation (yeh i know its no biggy)

[Keygrip]

Well - TAS calculations - I'm curious to see where this conversation goes now.

As a matter of pendantry, however, it should be called an "RPS" (Regional Pressure Setting) not a "Regional QNH"

Going off at a tangent somewhat - how many ATC'ers still call it a Regional QNH?? I know Bournemouth ATIS does - who else??

[iainpoll]

P16,

I would try a quick phone call to london information. Also you could try the London city ATIS.

If all else fails, jump in the aircraft, tune in London info, listen in for a few secs et voila

Iain.

[PhilD]

Q1 Given a reasonable variation between 'official' regional QNH and a QNH available in advance from (e.g.) Met Form 215, how much difference is that going to make to TAS?

Q2 Can you fly an airspeed that accurately?