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TailwheelFiend
8th Apr 2009, 16:02
[1] In areas that utilize QFE (I'm not sure where that is besides Russia, China ?) is the Transition Altitude always the same as the Transition Level, and if not, how often is it different?

[2] Have you ever had a problem obtaining a QNH altimeter setting from the controlling authority?

[3] Does your aircraft have direct measures to accommodate operating in a QFE environment, or do you need to use more manual methods?

[4] Is the altitude input to your EGPWS from GPS or from barometric altitude?

BelArgUSA
8th Apr 2009, 16:27
Russia and China continue to use QFE and metric heights and levels.
They never use QNH - They might (maybe) issue a QNH...
When I flew into these areas, we were QFE qualified, flew QFE and had metric altimeter.
I think Laos still uses it. North Korea does QFE metric. I think Vietnam is now using QNH.
Some areas are more complicated. UK, as an example.
UK, at times, use QFE, then QNH, then... QNE/STD...
xxx
My opinion, if you fly Russia or China, you better be fully QFE trained.
And your aircraft better have a metric altimeter.
Many disregard this advice. Until they will make a bad mistake.
xxx
:rolleyes:
Happy contrails

411A
8th Apr 2009, 16:33
I have had no difficulty obtaining QNH for ops into Russia...and in fact it was provided just for the asking, by the folks in the tower, as they, at the same time, were polishing off the last bottle of adult beverage at Christmastime.:}
They also asked what minima we needed.
The First Officer replied 550 meters....and 550 meters it was, even though on the ground you couldn't see s***.
Friendly folks.

latetonite
8th Apr 2009, 16:42
QFE trained? Is that something new? Operated out of Shanghai for a while, in a classic A300, and with the self prepared metric levels, on a card next to the "feet" altimeter, and some common sense, experienced no difficulties at all regarding altimetry. ATC was a different issue though.

TailwheelFiend
9th Apr 2009, 01:13
Moscow will occationally refuse to give you the QNH, and just reply with 'negative'. But it is simple to figure out; QFE+21 I think it is.

That might work for one of the Moscow airports but not all.

NZScion
9th Apr 2009, 01:39
My Jeppesen plates for Australia carry an annotation "Airfield Elevation xxx hPa". I can only imagine this can be used to calculate QNH/QFE when using one or the other. I can't comment on what is on the places for different regions. I also note that I've never needed to use it, as my company (and I assume all companies in Australia) use QNH at all times.

galaxy flyer
9th Apr 2009, 03:08
Yes, that notation is to convert between QNH and QFE. There is also a chart in Table and Codes section that can be used to make the conversion. Remember two large airlines, airlines that were early users of Jepp products used QFE in normal ops. American used it until the min-Nineties and Eastern used QFE until 1987, I think.

GF

Tmbstory
9th Apr 2009, 07:20
I used QFE and QNH in Far Eastern Russia with no real problems.

We had altimeters in feet, since the Australian Regulator would not allow two types ( metric and feet ) to be used at the same time.

Cards for metric levels were carried in the cockpit.

Russian ATC were quite helpful.

Tmb

Old Smokey
9th Apr 2009, 14:54
Many operations into Russia for me, I've never had any problems with immediate provision of QNH on request.

Many more operations into China for me, I haven't heard of QFE there for decades, it's all QNH. Perhaps some stations in the Chinese boondocks still use it.

Regards,

Old Smokey

galaxy flyer
9th Apr 2009, 17:49
OS

I presume your mob uses QNH rather than QFE in Russia or anywhere that uses QFE. We used QNH in the USAF, which combined with inches only altimeters created a godawful number of conversion any one of which could kill. In my present jet (Canadian built), we can convert to metric altimetry with feet also shown. This makes QFE a dream, once OFE ops are taught and briefed. I just went in/out of ULLI with a new F/O and he had no problem understanding it.

Why do airlines stick with QNH in QFE regions?

GF

BelArgUSA
9th Apr 2009, 18:16
Gentlemen -
xxx
I preach proper QFE procedures training (and metric altimeters).
My airline career was 51% instruction and 49% line flying.
So I preach for what provided me with employment and paychecks.
xxx
There are airlines that never need a QFE in training. Forget what QFE is.
Then some airlines say "request a QNH, that is it" - and go make a mistake.
Be sure to avoid fat fingers with your pocket calculators.
A 10 minute "mention" of QFE in classrooms is plenty of training.
That is the economic training solution adopted by many nowadays.
xxx
And then, there is/were airlines with 8 hrs classroom QFE/Metric training.
I worked and managed training with the last kind of airline mentioned.
Such training was required as per their FOM, for crews operating there.
And some airplanes were fitted with a metric (uncorrected) altimeter.
Such airplanes were required for any airplanes operating in such airspace.
I am certain modern equipment can do even better.
Rant completed.
xxx
:*
Happy contrails

Old Smokey
10th Apr 2009, 14:12
galaxy flyer,

Hi. "Why do airlines stick with QNH in QFE regions?"

Good question. In our case, the FMC can be operated in QFE mode (selectable), but after doing so VNAV becomes unuseable. Company policy is to make full use of LNAV and VNAV. (That doesn't imply that I agree with it!).

Operations of a QNH/Altitude in Feet/Subscale in hPa aircraft to regions where these three criteria do not apply is really a "no brainer". It's really no big deal so long as you stay on the ball.:ok:

Having said all that, it is my strong personal conviction that a great many CFIT tragedies occur due to altimetry errors of one sort or another. Consider the following differences between altimetry systems in various countries -

(1) Altimeter sub-scale in Inches of Mercury or Hectopascals,
(2) Altimetry measured in feet or metres,
(3) Variable Transition Altitudes and Transition Levels,
(4) Altitudes referenced to QFE and/or QNH, with possible mixing traffic.

I'm sure that there's more than this, but these immediately come to mind.

If a demented person wished to create havoc with air operations, leading to a steep rise in the possibility of CFIT, I doubt that they could do better than to introduce these conflicting systems.

I have no particular prejudice, I learned to fly in QFE operations, but went to work in a QNH environment. All of the systems have their good and bad points, but FOR HEAVEN's SAKE, let's have ONE system. I don't care which one it is, as long as it's ONE system.:ugh: I concede that for reasons of the highest terrain in a particular region, variation in Transition Altitudes and Levels would be necessary (It would be awkward to apply the Tibetan terrain constraints, for example, to the U.K.).

There are thousands of regulatory differences between various jurisdictions, the odds are that, apart from Altimetry, they probably won't hurt you if mis-handled. A pilot under pressure at night and/or bad weather flying an aircraft primarily equipped for one system, but flying into an "alien" altimetry system, is on a count-down to a CFIT. The Swiss Cheese holes are lining up.:mad:

Regards,

Old Smokey

Denti
10th Apr 2009, 17:31
It can depend on equipment too. Our 737s were not allowed to be operated in QFE after they got retrofittet with EGPWS, even now in factory fittet EGPWS planes it is not allowed as EGPWS in that installation cannot work with QFE. So we have to calc back and forth. To enhance crew awareness it is mandatory to document every altitude clearance in writing, even below FL100 if we are to operate in QFE regions.

Jofm5
12th Apr 2009, 04:53
Apologies for the minor drift. Had to look up the Q Codes as was interested in what you guys were discussing.

If I am correct in my research

QFE = based upon field elevation of an airport.
QNH = Pressure based upon nil height i.e. sea level.

So am a little confused as to why ppl are talking about the difference between imperial/metric.

Again apologies for the thread drift - will go back to reading - would be appreciative if you could answer why one would be measured in different units to the other.

Denti
12th Apr 2009, 07:53
True, imperial/metric doesn't directly imply QNH vs QFE, it just so happens that at least some, if not all, metric using regions use QFE operation as well. For example russia where QFE and metric is the norm. All in all more a coincidence than a fixed relationship between two different topics, both of which refer to altimetry and the big big problem of making a fatal mistake if you are not on your toes.

GlueBall
12th Apr 2009, 10:11
China's using QNH, at least at the larger airports, PVG, PEK . . .

But China's Flight Levels, incl RVSM airspace, is still metric; but again different from the metric FLs in Russia, and its former Soviet republics. :eek: