Altimeter settings: QNH versus QFE

I have a question for you CFIG's out the I recently moved to a
"flat" state from a "mountainous" state and noticed that every glider
pilot I have met and flown with in the "flat" state sets his altimeter
to zero (a QFE setting) instead of field elevation. Back in my old
stomping grounds, all my glider friends set field elevation (QNH).

I find this a bit disturbing - even dangerous. It's tough to
deconflict altitude on the radio when you don't know what the other
glider has set his altimeter to!

In response to my questions about why this practice of setting the
altimeter to zero is so common, invariably the response is "that's the
way I was taught" (from both old and new pilots) or that "it's easier
for the student to learn that way" from instructors. Does this mean
that flatland student pilots are mathematically challenged, while those
in mountainous areas are not?

I also hear "it's easier to tell how high up I am when landing". Huh?
What happened to no-altimeter/TLAR patterns? Or are people being
taught rigid altitudes in the pattern?

So - what gives? Is this technique commonly taught? Do instructors
really believe it helps their student? Is it even legal (how do you
get a current altimeter setting during a long flight)?

No prize for figuring out my opinion about this practice...

And please, no tangential discussion about using QFE for IMC approaches
- unless you have two altimeters in your glider...

Kirk
66

I've found that instructors who teach setting the altimeter to read zero at
field elevation are generally those who have no cross country experience in
either gliders or airplanes and can't grasp the concept of landing at
another location with a different elevation.

I teach setting the altimeter to QNH and how to get an updated altimeter
setting by radio. Complete knowledge of altimetry is required of all pilots
regardless of the aircraft they fly. I also teach TLAR for off-field
landings where the field elevation may be unknown.

BTW, does your altimeter read field elevation before takeoff when set to
local pressure? Most glider altimeters don't and should be calibrated.

bildan

wrote in message
oups.com...
I have a question for you CFIG's out the I recently moved to a
"flat" state from a "mountainous" state and noticed that every glider
pilot I have met and flown with in the "flat" state sets his altimeter
to zero (a QFE setting) instead of field elevation. Back in my old
stomping grounds, all my glider friends set field elevation (QNH).

I find this a bit disturbing - even dangerous. It's tough to
deconflict altitude on the radio when you don't know what the other
glider has set his altimeter to!

In response to my questions about why this practice of setting the
altimeter to zero is so common, invariably the response is "that's the
way I was taught" (from both old and new pilots) or that "it's easier
for the student to learn that way" from instructors. Does this mean
that flatland student pilots are mathematically challenged, while those
in mountainous areas are not?

I also hear "it's easier to tell how high up I am when landing". Huh?
What happened to no-altimeter/TLAR patterns? Or are people being
taught rigid altitudes in the pattern?

So - what gives? Is this technique commonly taught? Do instructors
really believe it helps their student? Is it even legal (how do you
get a current altimeter setting during a long flight)?

No prize for figuring out my opinion about this practice...

And please, no tangential discussion about using QFE for IMC approaches
- unless you have two altimeters in your glider...

Kirk
66

wrote in message
oups.com...

So - what gives? Is this technique commonly taught? Do instructors
really believe it helps their student? Is it even legal (how do you
get a current altimeter setting during a long flight)?

I could make an impassioned case for either setting, but 91.121(a)(1)
settles the issue. The altimiter is always set at the current reported
altimeter setting of an appropriate available station or at the elevation of
the departure airport. That is what I have always taught my students.

Of course, here in south Florida the question is pretty academic.

Vaughn

wrote in message
oups.com...
I have a question for you CFIG's out the I recently moved to a
"flat" state from a "mountainous" state and noticed that every glider
pilot I have met and flown with in the "flat" state sets his altimeter
to zero (a QFE setting) instead of field elevation. Back in my old
stomping grounds, all my glider friends set field elevation (QNH).

Wow....I'm not a CFIG but am one of Kirk's "glider friends in his old
stomping grounds" and for the life of me cannot even believe this discussion
is happening!!!

To do this is an enormous crutch and dangerous for anyone that will ever fly
outside of their local airport environment. How about mountains? How about
large towers there in the "flatlands" where elevations can vary even there
by a few hundred feet making your chart worthless. And as 66 points out,
how about the old "hey I'm in the same area you just said you were in,
what's your altitude?". How about the powered plane that is transitioning
your area and is smart enough to read the chart, see that there is a glider
ops there and makes a radio call to say that he is overflying from the south
at X altitude?

Finally the last but maybe best reason to NOT do this is that when stressed
we all regress to what we were first taught and our natural instincts. If
one of these folks taught on the QFE basis starts taking powered lessons
(God forbid!) or heads to another mountainous glider site and gets in
trouble they are going to revert to thinking in QFE format and that may end
up being a fatal error.

Casey Lenox
KC
Phoenix
(who just got back from Moriarty where it was supposed to be good but
watched it OD for 3 days!)

Kilo Charlie wrote:

How about mountains? How about
large towers there in the "flatlands" where elevations can vary even there

How about looking out of the window?

Stefan

Flying for 10 years over Northern Germany (which, except for the climate,
could be compared to Northern Florida) I always used a QFE setting with the
field 600ft MSL. Airspace regulations weren't that touchy in these days, and
sailplane altimeters aren't that precise anyways so there is just no point
to have it set at 400ft or 600ft. If you rely on judging your altitude by an
altimeter during the pattern for an outlanding, you shouldn't go x-country
in the first place. If you run into a high antenna or a tower on a hillside,
you should think about getting a new prescription for your glasses.

The last 15 years in the mountains are another story though.

--
Bert Willing

ASW20 "TW"


"Stefan" a écrit dans le message de news:
...
Kilo Charlie wrote:

How about mountains? How about large towers there in the "flatlands"
where elevations can vary even there

How about looking out of the window?

Stefan

1) we can't turn the altimeter setting enough to set it to zero elevation..
it does not adjust that far
2) how do you stay out of the overlying Class B airspace and ModeC veil
restrictions if you cannot accurately measure altitude above sea level
3) how do you stay out of Class A airspace on a wave or thermal flight (see
#2)
4) how do you know how high you need to be to clear that ridge line ahead or
that you have final glider altitude for that airport that is not home
5) you have some idea of the airport or "ground" elevation you are going to
land on based on reading the contour lines on the chart or airport
information

our field elevation is 2833 and we just spent a weekend at Lone Pine CA,
elev 3680
or maybe Cal City, 2454, or Tehachipe, 4220, and lets not even get started
on the great soaring sites in Utah or Arizona or Colorado.

Best to learn the mental math now.. then later when you travel west for the
first time.

BT

wrote in message
oups.com...
I have a question for you CFIG's out the I recently moved to a
"flat" state from a "mountainous" state and noticed that every glider
pilot I have met and flown with in the "flat" state sets his altimeter
to zero (a QFE setting) instead of field elevation. Back in my old
stomping grounds, all my glider friends set field elevation (QNH).

I find this a bit disturbing - even dangerous. It's tough to
deconflict altitude on the radio when you don't know what the other
glider has set his altimeter to!

In response to my questions about why this practice of setting the
altimeter to zero is so common, invariably the response is "that's the
way I was taught" (from both old and new pilots) or that "it's easier
for the student to learn that way" from instructors. Does this mean
that flatland student pilots are mathematically challenged, while those
in mountainous areas are not?

I also hear "it's easier to tell how high up I am when landing". Huh?
What happened to no-altimeter/TLAR patterns? Or are people being
taught rigid altitudes in the pattern?

So - what gives? Is this technique commonly taught? Do instructors
really believe it helps their student? Is it even legal (how do you
get a current altimeter setting during a long flight)?

No prize for figuring out my opinion about this practice...

And please, no tangential discussion about using QFE for IMC approaches
- unless you have two altimeters in your glider...

Kirk
66

I was taught to fly in meters above ground and do a mental conversion
by multiplying the meters by three and adding 4 500ft to get the real
altitude when speaking to the ATC. I then bought a glider without a
meter altimeter - only a ft one which is set to show altitude above sea
level. No more problem when speaking to ATC but found I was doing
reverse calculations to find out how high I was above the hard stuff.
Then I set my palm up with Soaringpilot which now has a digital terrain
model built in. Now I know exactly how high I am above the ground -
even when I fly cross-country in the mountain regions not far from my
airfield. My LX 5000 computer is set up to show my height above my home
field, which is more important for final glide than anything else.

Clinton Birch
LAK 12

At 07:30 01 June 2005, Stefan wrote:
I'd like to add that for aerobatic flight, it is common
to use QFE, for
obvious reasons. But then, aerobatic flights are usually
strictly local.

Stefan

Precisely!

And that is the attitude of hundreds of glider pilots
for the last 40 years. Strictly local. I was taught
that way of thinking in a J-3 cub back in 1953, and
then we used it in a glider club in the 60s.

It works fine if you are in an uncomplicated area and
stay local, but it is OLD THINKING! Hardly anyone
travelled to another site those days - even the Cessna
pilots stayed within 25 miles of the home airport (flat
country).

We have a few of those in our club -- guys who never
venture more than 10 miles away in flat land, but the
instructors don't allow it for students.

I'm surprised at the number of US respondents using
the letters QFE, QNH and that third one, which I have
already forgot. I'm even more surprised that no one
has asked what they mean.


QFE = field elevation
QNH = pressure level indicating altitude above sea
level
Q__ = pressure altitude for a standardized pressure
to use for high altitudes (above 18K in the US)


Now, What does the Q mean?

What are the words for NH and for that other one?