QNH or QFE ?
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The last bastion of QFE is the RAF , this is largely because it helps those flying a high workload fast jet that has minimal navigation kit recover using PAR ( usually with less than ten minutes fuel remaining) Did not need another thing to think about so having the runway at zero on the altimeter was a good idea.
Things have moved on and the fast jets carry far more navigation kit now so recovering aircraft in IMC is much less fraught so once the “When I was on Lightning’s” brigade has retired you can expect a change to a more international way of doing things.
I expect QFE to continue in UK flying clubs for some time as most of them still teach ancient techniques such as Gypsy style engine management when For the last forty years they have been operating Lycomings.
Things have moved on and the fast jets carry far more navigation kit now so recovering aircraft in IMC is much less fraught so once the “When I was on Lightning’s” brigade has retired you can expect a change to a more international way of doing things.
I expect QFE to continue in UK flying clubs for some time as most of them still teach ancient techniques such as Gypsy style engine management when For the last forty years they have been operating Lycomings.
Discorde: Until you can persuade flying schools to stop teaching QFE procedures then nothing will change! I have even noticed going into my nearest busy GA field that the A/G operators will refuse to give QNH to arrivals even when requested - only give it for departures!! Go figure.
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You might very soon run out of scale. The one I'm using most has 940hPa as smallest value.
I have even noticed going into my nearest busy GA field that the A/G operators will refuse to give QNH to arrivals even when requested
(and by the way, thanks for correctly naming A/G operators - there are those who want to call them controllers, even if they do not control any airspace)
Last edited by Jan Olieslagers; 3rd Aug 2020 at 15:58.
Discorde: Until you can persuade flying schools to stop teaching QFE procedures then nothing will change! I have even noticed going into my nearest busy GA field that the A/G operators will refuse to give QNH to arrivals even when requested - only give it for departures!! Go figure.
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Since the last part of flying is done visually, is it really that relevant having your altimeter show 0 when landing at all? Once you pass the DH or DA you look out the windows anyway... or am I doing something wrong here?
I guess that most of the anti-QFE contributors don't have display authorisations. The vertical limits are all expressed in heights in "CAP 1724 Display Standards Document". Converting altitudes to heights several times in an aerobatic figure is probably not good for a display pilot's health. Yes, the need to set QFE is not necessary for most regions of flight - but for some activities it makes more sense than QNH. I'm sure contributors can find other examples where QFE is the safest option. Not all flights are take off - cruise - land.
This argument has gone on for as long as I can remember. to the extent its almost pointless. I would hope that anyone performing low level aerobatics will have it firmly implanted in their minds the altitudes or heights that must be achieved both at the top and at the bottom of a manoeuvre. The QNH pilot listens in a wonder of disbelief that anyone would mess around with the altimeter at critical moments (resetting to QFE). Knowing the elevations is part of everyday flying for QNH pilots. The only rule that I demand is that you fly one or the other and then use it at all times, but never mix it. If an a/g operator refuses to pass the QFE or other wise QNH ( a FISO or ATC will never refuse) this will require a very stern chat with the fool after landing such that he/she will never refuse to do so again.
In the majority of countries throughout the world QNH is the norm.
In the majority of countries throughout the world QNH is the norm.
I was born and bred with QFE & used QFE for 33 years of RAF flying.
I much prefer QNH.
(& in my glider always have height + altitude + FL all on display in front of me; modern electronics)
I much prefer QNH.
(& in my glider always have height + altitude + FL all on display in front of me; modern electronics)
In the USA (and other countries) how do pilots performing aerobatic displays above high-elevation airfields set their altimeters?
Discorde,
The same way as everyone else - they use the current Altimeter Setting (QNH* to you) and then convert all their gate heights to the appropriate altitude.
Of course, sometimes pilots get it wrong:
Just out of interest, I checked the Winter altimeters in my club’s two-week old ASK21B. With the field elevation of 3700’ set, the sub-scale read 1020 mb. I then made 43 twists of the knob to bring the altitude to 0’ and the sub-scale read 997 mb. I was surprised I was able to do this. Last time I tried this many years ago on an old US altimeter, I ran out of sub-scale.
The observant will notice I used mb rather than inches. This is because our glider was delivered with European altimeters! We shall be having words with the factory!
Using the Altimeter Setting doesn’t seem to cause any problem for new pilots. Our students have no difficulty figuring out that the downwind leg starts at 4500’ (800’ AGL).
* I would guess that 99% of North American light plane pilots would have no idea what QNH, QFE or any of the Q codes are.
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On a side note, when I flew glider, we had a polish model, and the altimeter was in metres.... which is probably "meters" now that the UK has left the EU.
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The QNH pilot listens in a wonder of disbelief that anyone would mess around with the altimeter at critical moments (resetting to QFE). Knowing the elevations is part of everyday flying for QNH pilots. The only rule that I demand is that you fly one or the other and then use it at all times, but never mix it.
Since this thread seems to have risen from the dead, may I ask what altimeter settings do people who fly glass cockpits with a standby steam gauge use on each? I flew with someone recently who kept QNH on the G1000 but 1013 HPa on the standby dial. I don't really see the logic of that, is there a 'best practice' for this situation?
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Since this thread seems to have risen from the dead, may I ask what altimeter settings do people who fly glass cockpits with a standby steam gauge use on each? I flew with someone recently who kept QNH on the G1000 but 1013 HPa on the standby dial. I don't really see the logic of that, is there a 'best practice' for this situation?
But I guess the more professional know the answer better than I..
There are some justifiable reasons for setting standard pressure on the second altimeter: should your flight altitude be close to the base of an airway/controlled airspace, which is designated as a flight level, because it could act as a valuable heads up. Similarly when flying using regional pressure (UK) then having the aerodrome QNH set on the second altimeter does a similar job when flying below the base of controlled airspace which is designated as an altitude. For those who land using QFE then having the aerodrome QNH set on the second altimeter is a common practice, ready for a go around and diversion.
But, once again we return to the possible folly, in the minds of QNH people, of fiddling about with altimeters at a critical point in the flight. QNH, QNH and only QNH is the normal standard of IFR pilots and also for those who regularly fly internationally. Outside of the UK and France QFE is rarely found. It was a common practice for commercial transport flights to land at one place using QNH and another using QFE, whatever was provided locally. This could happen many times on the same day and was a recipe for disaster. I can remember a number of tragedies with a considerable loss of life owing to the miss-setting of the altimeter by the pilots during the approach to land.
But, once again we return to the possible folly, in the minds of QNH people, of fiddling about with altimeters at a critical point in the flight. QNH, QNH and only QNH is the normal standard of IFR pilots and also for those who regularly fly internationally. Outside of the UK and France QFE is rarely found. It was a common practice for commercial transport flights to land at one place using QNH and another using QFE, whatever was provided locally. This could happen many times on the same day and was a recipe for disaster. I can remember a number of tragedies with a considerable loss of life owing to the miss-setting of the altimeter by the pilots during the approach to land.
Last edited by Fl1ingfrog; 5th Aug 2020 at 09:51.
