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-   -   Why do the RAF still use QFE? (https://www.pprune.org/military-aviation/387724-why-do-raf-still-use-qfe.html)

WX Man 4th Sep 2009 18:32

Why do the RAF still use QFE?
 
Just pondering the thought. Why do RAF pilots still use QFE? As a civvy pilot, I use QNH all the time, everywhere... except RAF bases. Just wondering why.

Pontius Navigator 4th Sep 2009 18:42

We went round this buoy many times and in 1990 Lady Lucinda Buck's lover decreed that we went to QNH. At great expense, and contrary to all advice at the time, we went to QNH. After the Daily Mirror expose the first thing that was done was to revert at great expense to QFE.

The RAF does use QNH at many airfields such as Kandahar and Nairobi.

Fast Pussy 4th Sep 2009 18:42

Dah!! 'Cos it tells you how high you are above the point you intend to land at??? Without having to do any mental gymnastics???????

Go to any shop and watch today's teenager giving you change - do they do mental arithmetic, or do they look at the screen to decide how much money to give back to you?? And who provides today's pilots?? Mr QNH, or Mr Let's Keep It Simple???

And anyway - the Americans work on QNH, so that's as good a reason as any for using QFE!!

:yuk:

scarecrow450 4th Sep 2009 18:55

stops you flying into the ground ?

bast0n 4th Sep 2009 19:06

No brainer - most people would like to see zero on the altimeter as the wheels touch the ground not some mystical height you have to think about............:ok:

KISS:)

Sierra Hotel 4th Sep 2009 19:28

From what I was told, only this week, commercial pilots use QNH for procedural approaches, whilst the military are on QFE. In GA pilots may opt for either.

HEATHROW DIRECTOR 4th Sep 2009 19:30

<<but in Commercial Aviation they use QFE for instrument approaches. (I may be out of date on this).>>

Unless things have changed since I retired 7 years ago, just about all airlines use QNH. The last ones to use QFE thar I recall were Aer Lingus and one or two east European companies, but they had changed by the time I left. Someone more up-to-date will no doubt comment.

Pontius Navigator 4th Sep 2009 19:35

HD, I will accept that as my info pre-dates your retirement.

That Sir Peter temporarily got the RAF to use QNH and the RAF then rebelled is not in doubt. Perhaps one of the few cases where we actually changed back.

Paul Chocks 4th Sep 2009 19:45

The only real value of QFE, that I can see, is to make a circuit look pretty on the altimeter. Downwind at 1000' and final at 500' for example.

I don't ever recall looking at the altimeter as I touchdown (if you really needed to know your ht a rad-alt would be better)

On instrument approach it matters not, as long as you know which datum is set and then fly to the appropriate minima.

QNH (or RPS) much better for terrain clearance and stopping you from entering controller airspace from below.

QFE may help for elementary/basic cct trg, but for anything else, I'd go with QNH.

Tankertrashnav 4th Sep 2009 20:01

We used QFE at Lands End (yes it is a civvy airport) till our club folded there this year. Or was that just to make it easy for us studes, as implied by Paul Chocks?

XL319 4th Sep 2009 20:09

I think the rules changed last year didn't they? All aircraft preparing for take off are given QFE unless QNH is requested.

octavian 4th Sep 2009 20:27

The only organisation in the UK that would appear to routinely use QFE is the RAF (plus, I assume, the RN and AAC?), although I don't know what the formerly shiny fleet at Brize and the Truckies at Lyneham use.

All datums at significant civil aerodromes are based on QNH and I know of no airline or AOC operator (UK or otherwise) which uses anything other than QNH for visual or instrument approach work. All the charts published (Jepp, Aerad etc) use QNH with heights referred to threshold/aerodrome elevation in brackets (presumably for the RAF). For Nairobi and other similarly elevated aerodromes, I seem to recall that QNE was the most used practice given the limitations of altimeters.

Given that, in a relatively short flight outside controlled airspace, a relatively inexperienced or student pilot, not to mention those of greater experience, can be instructed to fly on 3 or more potentially widely spaced pressure settings QNH, Regional Pressure Setting, QFE, Standard (1013.2) if feeling brave, perhaps another RPS and another aerodrome QNH, the potential for confusion and misreading/mis-setting altimeters with all these changes of setting is, I would suggest, greatly increased.

In these days of constantly updated information are RPS really relevant? These would appear to date from the days of the Shackleton and Dakota when pilots were out of communication for prolonged periods and needed a FORECAST RPS for the areas in which they were operating.

Is QFE really necessary? Even for a Surveillance Radar Approach the controller passing an advisory altitude based on QNH is giving the pilot a figure to which he/she may adjust rate of descent. At Decision Altitude/Minimum Descent Altitude the pilot will take an appropriate action on the basis of that altitude. Seeing zero on the altimeter at the threshold is an irrelevance, as at the threshold it may need to read 50ft or so.

Let's just have QNH and Standard and be done with it. And whilst we're about it let's have a standard transition altitude. Howzabout 10,000ft. So that'll knock it down to a very few pressure setting changes for those unpressurised aircraft operating outside CAS and below 10,000ft.

Standing by for incomers..........

farsouth 4th Sep 2009 20:41

With you all the way Octavian, thanks for saving me writing similar

WX Man 4th Sep 2009 21:26

Interesting responses (and so many, in so short a time!). Seems to me that the arguments for using QFE are:

- to fly a circuit you don't have to add 1000ft to the aerodrome elevation
- to fly an approach you don't have to get into the mindset that the hard stuff isn't going to be where the height pointy thing says "0".

Given that I'm no mental arithmetic genius and that I can still do both of the above, I'm guessing that the guys and girls who are far brighter than I and lucky enough to be flying some of the finest flying machinery known to mankind can probably also do the same.

There is only one occasion where I can think that having QFE set is actually more sensible than having QNH, and that is when you're flying a PAR. Other than that, I see no reason why everyone shouldn't have QNH set all the time (when they're below transition).

FWIW, I'm totally with Octavian. Simplify the whole darn shebang, so that everyone in uncontrolled airspace is flying on the most accurate QNH available (RPS? WTF?). From the geezer in the microlight at a private strip, to the guy in the Typhoon transiting to the exercise areas, to airliners entering the shark infested custard between airway and (for instance) Teesside/Plymouth/Doncaster's zones. Everyone uses QNH below 10,000ft: *highly* sensible. In fact: let's have a Europe-wide altimeter policy, where everyone below the highest terrain (Mont Blanc, 15,781ft) uses QNH: round it up and let's call it 18,000ft... which, funnily enough, would bring Europe into line with the USA.

So, Octavian, I'm with you on this one. I wonder how many other folks are?

walter kennedy 4th Sep 2009 21:30

What about an LZ, say in an op area, with no ATC? Throw in marginal conditions.
Which would be best?

bast0n 4th Sep 2009 21:35

Walter

Ha Ha - you have said it matey!!:ok:

Roland Pulfrew 4th Sep 2009 21:40

WX Man

I'm not. QFE is only use in the circuit area/instrument approack. When the wizzy FJ is zipping around at low level it does use QNH, in this case the regional pressure setting. I for one prefer to land at 0 feet, and when I am landing somewhere else a lot higher I will treat it with the caution that it deserves.

Why should the RAF change? It works for us, if you don't like it, don't fly into RAF airfields.:hmm:


would bring Europe into line with the USA.
And that surely is the best argument for not doing it!;)

bowly 4th Sep 2009 22:10

Roland makes a valid point. It is much easier (and safer) to always see the same numbers whichever airfield you are using. Your 400' point is always your 400' point and not some random figure you've calculated after 8 hours sausage side! I'm with the KISS brigade.

Tankertrashnav 4th Sep 2009 22:15

Slightly off thread but do they still use inches over the other side of the pond? I seem to remember that when the RAF bought the Phantom they spent about a trillion pounds fitting them with Rolls Royce engines and various other mods but balked at twopence halfpenny per aircraft to alter the altimeter scales to millibars, requiring every ATC for years to come to pass altimeter settings to Phantoms in inches. Great fun in tankers (using millibars) with a pair of them in tow.

chiglet 4th Sep 2009 22:23

Octavian,
Simple. Just put in a "Request for Change"......:E
We all know what will happen. A "Hissy Fit" from Ops, then quietly filed in File 13 [the LATU box]


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