QFE/QNH for take off/ landing
 

Doing some research for an article , I remember USSR/Russia and even the UK used QFE instead of QNH on APP. in the 1970s Were there a distinctive advantage on using QFE and does anybody remembers the year when that stopped and got standardized on QNH?

As I remember, we changed to QNH in the late 1970s. There are two main advantages (1) less adjustments to the altimeter baro settings therefore less chances of making mistakes, and (2) you can keep track of the MSAs more easily around the airfield. When you have a radio altimeter, QFE becomes redundant.

QFE still in use at British military airfields.

QFE still in use in China in military airports where we operate like Nanning and Yiwu airports. Not a biggie.

QFE makes much more sense and is more logical for circuits and training imo though it is impractical if the airfield is at a substantial elevation.

Thanks everyone for the info so far , Pineteam : Idid not know it was still used today in International airports, I just checked their METAR , it gives the QNH.. On arrival they give you the QFE on the frequency? Elevation is around 420ft so quite a difference between the 2
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meleagertoo is right about circuit training and sport flying in light aircraft. My comments related to airline operations where you fly to a large number of different airfields.

Hi ATC Watcher,

Yes, they will clear you in QFE. Any altitude below 3000 Meters ( they still use the metric in Mainland) will be issued exclusively in QFE. We still fly using QNH as reference using a conversion chart as shown below. QNH is available on request with ATC or via DATIS.


https://cimg6.ibsrv.net/gimg/pprune....79e4187a8.jpeg

I believe that the British Military attempted to align with the civilian work in the 1990s by changing from QFE to QNH but, correctly in my personal view, reverted back to QFE. The issue about which system to use is really down to culture and culture change is challenging due to cognitive recognition. However, having operated in QFE and QNH environments for approximately equal amounts of time each, when correctly using SOPs the biggest ground proximity waning ever is an altimeter approaching zero, you do not need EGPWS call outs. After 45 years of aviating in both environments my vote is for QFE.

MM

I, likewise have operated both QNH and QFE for equal parts of my (almost exactly!) 55 years in the air. I am with MM; QFE gets my vote for final approaches and circuit work every time.

Mog

[QUOTE=Miles Magister;11180591] After 45 years of aviating in both environments my vote is for QFE. /QUOTE]

What is the highest airport at which you have operated using QFE? I often fly between airports with an elevation difference of over 5,000 ft. Even if the altimeter could be set for QFE at both airports it would take a long time to change the baro setting, a distraction I don't need.

I think the only time I have seen QFE used in USA is at low elevation gliding sites where the flights were expected to be local. I hated it and always changed to QFE when I flew.

MD-11 (also MD-10 and 717) PFD was designed for very easy switching between QFE and QNH with both baro setting being retained in memory. Don't remember if that was standard or a customer option.

AA and EA used QFE for along time. At EA, we used for field elevations below 1500’, IIRC. Captain Eddie set that standard after surviving a crash in Atlanta. AA stopped using in 1995 after striking a tree on ridge line partly attributed to pressure falling rapidly and no updated QFE.

I grew up in QFE operation while gliding. In professional operation it was always QNH, even when operating into QFE airfields in Russia (LIDO charts mention the QFE offset to QNH).

The most dangerous thing i actually experienced was a very low number of ex-Chinese A320s we got at one point in our fleet who had the QFE customer option, which meant that the Standard/QNH setting had one additional step via QFE. How many people did not click it often enough to get the correct setting was really frightening.

I use qfe when flying aerobatics..

I have never flown QFE.
The good thing about QFE is that the pattern altitude is always 1500', stable is always 1000', Touchdown is always 0'. Potential problems are when transitioning into/away from the pattern, as all other altitudes will (and should!) be based on QNH/MSL. Having to set a third setting increases the risk of making mistakes (QNE - QNH - QFE) every arrival, and the reverse every departure, might offset the advantage of having QFE during T/O and landing. Based on the fact that the vast majority of professional aviation uses QNH over QFE makes me think QNH is better.

I've used both in my time (civvy then RAF then civvy again). The advantage of a QFE landing is that it removes the need for mental maths on final approach.

Changing from QNH to QFE to QNH isn't difficult - especially if you follow a checklist!

As a helicopter pilot it is relatively easy to approximate a local QNH yourself if you land at a remote site out in the sticks away from an airfield and have to depart after some delay when the barometric pressure has changed - provided you know the elevation of the landing site. Setting QFE in those circumstances is meaningless.

I cheat and just use the RA. Works most of the time.

Going through initial USAF pilot training (1982) we were subject to myriad acronyms. QFE translated into Q f'n English. LOL fellow aviators. Hilariously enough, I got to use QFE often times again in terminal ops with American Airlines as a new-hire.

We had some of our A320 with that QFE option. It was latter removed to avoid this kind of issues.

I've used several systems and still do. Principly QFE below transition altitude except for 70s flights to Moscow where we used similar tables to the current Chinese ones. Fortunately it was three pilots and we wrote everything down which lessoned the workload but there were times no one except George was flying the aircraft.
Bergerie mentioned what we used on the VC10 which lead to the game park warning system incident into Nairobi were confusion reigned and they did a touch and go at night in a clearing.
My third outfit was QNH but our training was high level and flying was very sporty which led to an incident in my line training flying into Geneva 05 with some very inclement weather.I elected to do a dirty dive in the hold without doing the full approach procedure which went very well until the outer marker check which showed a 1,000ft plus discrepancy. The training FO and captain were as puzzled as moi meme until I realised the discrepancy was the beacon altitude above the threshold. I was following the 6 degree glideslope which was easily rectified; throttles idle; land flap and flight director off.
Later I got into gliding followed by instructing which is another ball game.
UK QFE in the circuit but teaching height assessment using visual clues..QNH cross country with the difference with standard written down for airspace.
France has a simpler system for the mountains but that is with speed in kph, altitude in metres, vario MPS and using hiking maps marked with circles of 10km increments with the QNH/standard difference scrawled down. The above allows one simply to calculate gliding range to land able terrain (at 20 to 1) and how far up a mountain face one is going to arrive (hopefully). It becomes more complicated if your glider instruments are impérial and your position reports have to be in altitudes (french) not forgetting the earlier flight computers could be in another set of numbers.
I did have an air miss during circuits whilst instructing at Blackbushe where an incoming aircraft forgot to set QFE and came through the circuit just below cloud base on his way to a dead side joining.
Have a sophisticated instrument for paragliding..set to take off QFE for return to top land and my car but on cross country it’s back to mental gymnastics wrt airspace. Fortunately there are GPS systems programmable with airspace.

Interesting remark, do you remember the phraseology you used when passing the pressure? , did you say "Fox Echo 1020" or just : "Altimeter setting 1020 " and did you pass it in Millibars or in millimeters of mercury ?

Thanks a lot for the info, , super photo ? I am sending you a PM .

Some RAF colleagues of mine had a big scare during a non precision helicopter approach to a German military airfield (early 1980s; might have been Buckeburg, not sure) when they came out cloud only just above trees on a ridge. They thought they were flying on QFE but had actually been given the QNH. Bearing in mind that this was forty years ago, I’m glad to say that due to the honesty of the crew and the publicity this was given at the time, I was lucky enough to have learned from someone else’s mistake rather than my own. Hopefully others did too. If in doubt, always cross check.

What’s QFE? :p

When I started gliding in my teens, you set the altimeter to zero on the ground, but as soon as I started flying cross-country, I changed to QNH all the time as the numbers printed on the map actually meant something then, in terms of airspace and terrain, and when talking with other pilots you had a common datum.

I’ve done a fair amount of airline ops using QFE where you had to, made a bit easier by a QFE option in the FMC as well as a metres one. Ditching QFE means one less pressure setting to forget out of QFE, QNH and QNE and there are lots of major airports that are high enough that many altimeters can’t be set to QFE anyway.

If you do all your flying on QNH, you just get used to it. Ultimately, the solution is going to be geometric altitude which will remove pretty much all the disadvantages of pressure-based systems.

Never heard of that one . You care to elaborate ?

For a conventional mechanical altimeter on which you adjust the datum by moving the sub scale, the most used standard says they should be adjustable ~950mb to ~1050mb, so anywhere between -1,000’ and 2,000’ pressure altitude. Electronic ones have a wider range, I believe from ~750mb to ~1050mb, which would still cause problems trying to set QFE over 8,000' airfield elevation, like Bogata and many other airports in South America and China.

I think it's horses for courses really. I've operated both with different types of operation. If you've been brought up on QNH during initial training you don't think twice about the issue of calculating pattern altitude.
But then again the QFE/QNH debate is as old as aviation.
One thing I do know observing in the simulator is I've seen more bust missed approach heights/altitudes when the approach has been flown on QFE and QNH has not been set on the Go Around; this applies in particular with higher performance aircraft with a relatively low level off.
I was with one operator when we changed from QFE to QNH operation in the 1980s and thereafter I rarely saw a bust missed approach altitude on a Go Around.

……….and didn’t we both work for an operator which used both at the same time !
I seem to remember the call “ qfe, qnh difference checked “ !

There have been times when the QNH exceeded both the upper and lower limits.

I’m sure that when I started out some airline SOPs used QNH and others QFE and the RAF seemed to change their mind which to use every time they got a new OC pressure setting. In a radio-optional VFR world I always thought QNH gives you more - you’re always likely to be in the right ballpark area for terrain clearance and rejoin from the airfield overhead.

Fireflybob +1. I’d suggest it depends on the operation.

I’d suggest QFE for circuits well away from controlled airspace. QNH if there is controlled airspace nearby or overhead. I’d agree a potential threat with QNH for circuit work is the possibility of confusion in the event of an EFATO but that can be briefed as part of TEM.

Airline ops seem to work fine with QNH as MSA, terrain etc defined wrt altitude. As others have mentioned at a high altitude airport winding off QFE may be impractical if not impossible. Other areas like fast jet and rotary I’ve no experience so I’ll leave to others to comment.

From a Met point of view [and I ceased being involved in 1997 so may be behind the curve]
The barometric pressure is to be read "frequently" when pressure is changing rapidly, and a "Special on QFE" issued to ATC against a signature or initials.

This was done scrupulously on RAF stations, with highly skilled and well-motivated observers who were often on watch solo. It was mandatory to keep a running log of pressure [hourly or half-hourly] and the observer was expected [of course] to be conversant with the overall Met. situation. We regarded monitoring of pressure as Holy writ, drummed into us on Day One..

Some airport you do not even set QNH but QNE, yes not QFE.. QNE.. Have a read :-) Interesting ..

Retired BA/BY yes that too!

Because the Kollsman (?) altimeter on the RH side referenced the pressurisation for landing until they retrofitted a standby altimeter which did that job and then a proper servo altimeter on the RH side - happy days!