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Old 19th September 2007 | 06:30
  #28 (permalink)  
BEagle
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Joined: May 1999
: ATP+Mil
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From: Quite near 'An aerodrome somewhere in England'
I couldn't agree more about the need to standardise RTF phraseology!

The military may have additional requirements, such as the VRIAB for tactical formation rejoins, but where calls could be standardised, they should!

Having submitted a CHIRP after a mil ATCO cleared an a/c to line up when we were at 1-200 ft having been given landing clearance, the Purple People who run what used to be IFS were more interested in crucifying the controller than explaining why the aircraft cleared to line up couldn't be given a conditional clearance such as "After landig traffic, line up and wait" or words to that effect.....

The truth is that the military doesn't have enough people left to conduct a full review and standardisation of their RTF procedures.

The military is a minority airspace user these days and should move into line wherever possible

Incidentally, the move back to QFE in recent years was driven not by training or ME opinions.........

The biggest hazard faced when flying an instrument approach on QFE is the risk of a level bust on the go-around where that is defined on QNH. I used to take RAF VC10 pilots on IRTs to Lulsgate (before theym Brizzle folk got fed up with the noise!) - the difficulty of controlling the aircraft on the go-around whilst trying to reset the main altimter subscale showed up the hazards of mixed QFE/QNH instrument procedures.

At the Covert Oxonian Aerodrome, light aircraft are required to fly on QFE on departure/arrival via the VRPs. Yet the CTR limit is defined as 3500 ft amsl.... Frequently, 'zone crossers' are called to all traffic in the CTR - but whether 'height' or 'altitude' is being used is often unclear. So you may have up to 300 ft less separation than you thought you had! Not one military aircraft operating in a QNH-defined CTR will actually be using QNH - how logical is that? On departure they use QFE, changing to SPS when cleared to a FL or on passing 3000 ft QFE, whichever sooner and upon arrival they change from SPS to QFE when cleared for the Instrument Approach Procedure.

There is also an RAF aerodrome whose MATZ is beneath the London TMA. Yet still they insist on a Transition Altitude of 3000 ft "Because that's standard"....... Top of the MATZ is 3203 ft amsl, base of the TMA in one part of the MATZ is 3500 ft amsl.

To highlight to US-trained PPLs the lunacy of UK altimeter setting procs, I take them from Brize via the Faringdon VRP to White Waltham, then back via the Oxford/Kidlington overhead to the Burford VRP. This requires Brize QFE, then the Cotswold RPS (another utter anachronism), then Benson QFE, then London QNH, then White Waltham QFE, then London QNH, then Benson QFE, then Cotswold RPS, then Oxford/Kidlington QNH, then Cotswold RPS, then Brize QFE. That's 5 different altimeter settings on the way to White Waltham and 7 different settings coming back - madness!
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