Altimeter Setting

In article
,
ContestID67 wrote:

We did have one incident related to the AGL/MSL switch that might be a
good to read about. One day yours truly flew a club ship and set the
altimeter to MSL. The next pilot was an die hard AGL'er. The AGL'ers
were used to finding the altimer not quite at zero due to barometric
changes and would "tweak" the altimeter to zero at the start of each
flight. Our field elevation is 888 feet. So the next pilot tweaks
the altimeter to "zero" but instead of subtracting 888 feet (by moving
the hands CCW), he tweaks it CW and adds 112 feet! Can you see where
this is going?

I did pretty much the same thing in my MSL-only club. Atmospheric
pressure had changed by 6-700ft from the last time the plane had flown,
and I did the nearest-thousand thing you describe. Even better, I
actually managed to do this twice in a row in our ASK-21! Discovered it
when I got off tow. Casually asked my passenger what his altimeter said,
and this discovered I'd managed to screw up both of them. Easy fix in
the air once I realized what I'd done.

Watch that thousands hand when you set your altimeter, and know what
your altitudes look like outside the cockpit!

--
Mike Ash
Radio Free Earth
Broadcasting from our climate-controlled studios deep inside the Moon

On May 31, 11:06*pm, ContestID67 wrote:
Rolf,


So about 5 years ago my Club's flight chair said that flying AGL was
wrong, dangerous and (if I am not mistaken) illegal. *

The "legal" issue is a slippery slope. Newbies to the sport (and I
still consider myself one) may take everything their instructor says
as the bible. Seems like learning and adhering to the FARs is a
critical part of soaring. If we're taught to break certain FARs from
the get go, what is the lesson there?

Rob

On Jun 2, 10:43*am, Rob wrote:
On May 31, 11:06*pm, ContestID67 wrote:

Rolf,

So about 5 years ago my Club's flight chair said that flying AGL was
wrong, dangerous and (if I am not mistaken) illegal. *

The "legal" issue is a slippery slope. *Newbies to the sport (and I
still consider myself one) may take everything their instructor says
as the bible. *Seems like learning and adhering to the FARs is a
critical part of soaring. *If we're taught to break certain FARs from
the get go, what is the lesson there?

Rob

That maybe you have the wrong instructor.
UH

On Jun 2, 10:57*am, wrote:
On Jun 2, 10:43*am, Rob wrote:

On May 31, 11:06*pm, ContestID67 wrote:

Rolf,

So about 5 years ago my Club's flight chair said that flying AGL was
wrong, dangerous and (if I am not mistaken) illegal. *

The "legal" issue is a slippery slope. *Newbies to the sport (and I
still consider myself one) may take everything their instructor says
as the bible. *Seems like learning and adhering to the FARs is a
critical part of soaring. *If we're taught to break certain FARs from
the get go, what is the lesson there?

Rob

That maybe you have the wrong instructor.
UH

Perhaps, but the student is the wrong person to judge the
professionalism of the instructor. I seem to recall that as one
of the 1 hour sessions in my last CFI clinic, after all. All of us
instructors do have the duty to be professional about what we're
teaching.

When I started flying many years ago the glider operation used
QFE since we were only doing local flying. It was pointed out at some
point that we would have to convert to doing it the proper way, but
that
pattern ops were easier to teach that way. Later I moved to
a club environment that pretty much used QNH. I took my flight test
there and it was pointed out that you had to switch over to QNH
before you could take the test. After that, I moved to yet another
club that was mostly using QFE, but after several years Tom came to
visit, and we've used QNH since then. I have to say that it never
really
bothered me as to which setting was in use.

Whenever going cross country, of course, I have always used QNH and,
for that matter,
I never look at my altimeter once I'm established on downwind, anyway.
At the very first place we used Tom's landing checklist that ended
with
"ignore the altimeter", and that's stuck with me all along. I fly
at least 80 flights a year as a primary instructor, and truthfully I
can't tell
you at what altitude we turn base or final. I judge those turns
entirely
by angle.

-- Matt

On May 31, 10:07*pm, Rolf wrote:
Over the years (30 or so) Caesar Creek Soaring Club has vacillated
with setting the altimeter to zero or MSL. Last year the Board decided
to put the Club ships on an MSL basis (private gliders exempted).
There are however a number of members who are continuing to make it an
issue. I would be interested in your thought and comments.
Thanks
Rolf Hegele
CCSC President

Rolf, if memory serves me right, the FARs are clear about it: setting
to MSL is required.

On May 31, 10:14*pm, GM wrote:

Rolf, if memory serves me right, the FARs are clear about it: setting
to MSL is required.

I don't recall any regulation requiring the altimeter to be set to QNH
unless the particular operation requires it (eg. an instrument
approach).

In article 150flivver writes:
On May 31, 10:14=A0pm, GM wrote:

Rolf, if memory serves me right, the FARs are clear about it: setting
to MSL is required.

I don't recall any regulation requiring the altimeter to be set to QNH
unless the particular operation requires it (eg. an instrument
approach).


14 CFR 91.121 (aka FAR 91.121)

For extra credit, note 91.121(a)(1)(i) which says you must use the setting
from the local radio source in preference to setting to the field elevation.
As was pointed out in this group a couple years ago, the examiner in the back
seat knows that regulation.

Alan

On Jun 2, 12:38*am, (Alan) wrote:
In article 150flivver writes:

On May 31, 10:14=A0pm, GM wrote:

Rolf, if memory serves me right, the FARs are clear about it: setting
to MSL is required.

I don't recall any regulation requiring the altimeter to be set to QNH
unless the particular operation requires it (eg. an instrument
approach).

* 14 CFR 91.121 * (aka FAR 91.121)

* For extra credit, note 91.121(a)(1)(i) which says you must use the setting
from the local radio source in preference to setting to the field elevation.
As was pointed out in this group a couple years ago, the examiner in the back
seat knows that regulation.

* * * * Alan

Yeah, but as for 91.121 you're not maintaining any particular cruising
altitude or flight level when operating a glider. I certainly agree
that cross country gliders should be operating off QNH but if you're
flying locally, you should have the option of setting QFE. I fly a
towplane and use QFE 99% of the time--any position calls I make I
convert to MSL (I have a table to reference on my legboard). If I
have to go and retrieve a landout, I'll use QNH.

"Yeah, but as for 91.121 you're not maintaining any particular
cruising
altitude or flight level when operating a glider. "


The FAA legal department told me they recognize the problem /
confusion with the English language usage used in the regulation.
Gliders do not "cruise." However, the intent of the rule is clear.
Glider pilots must be aware of airspace altitude restrictions
including aircraft cruising.

Recognized exceptions to setting the altimeter to MSL include crop
dusting and aerobatics.

Yesterday, there was a very close near-miss with a glider and
commercial jet descending for a landing. The club where the glider
flies commonly uses and teaches using AGL altimeter settings.

It will only take a very few of these encounters for gliders to be
required to have ADS-B transponders and perhaps be banned from certain
airspace near airports where larger aircraft fly altogether.

A new, highly accurate GPS satellite was launched yesterday. First of
a series leading up to the new transponder technology.

Tom Knauff

On Jun 2, 8:04*am, 150flivver wrote:
On Jun 2, 12:38*am, (Alan) wrote:





In article 150flivver writes:

On May 31, 10:14=A0pm, GM wrote:

Rolf, if memory serves me right, the FARs are clear about it: setting
to MSL is required.

I don't recall any regulation requiring the altimeter to be set to QNH
unless the particular operation requires it (eg. an instrument
approach).

* 14 CFR 91.121 * (aka FAR 91.121)

* For extra credit, note 91.121(a)(1)(i) which says you must use the setting
from the local radio source in preference to setting to the field elevation.
As was pointed out in this group a couple years ago, the examiner in the back
seat knows that regulation.

* * * * Alan

Yeah, but as for 91.121 you're not maintaining any particular cruising
altitude or flight level when operating a glider. *I certainly agree
that cross country gliders should be operating off QNH but if you're
flying *locally, you should have the option of setting QFE. *I fly a
towplane and use QFE 99% of the time--any position calls I make I
convert to MSL (I have a table to reference on my legboard). *If I
have to go and retrieve a landout, I'll use QNH.- Hide quoted text -

- Show quoted text -

Interesting. I also fly a towplane for a club and use QNH exclusively
- so when I call the glider release, it's MSL and doesn't need any
conversion (and associated potential for mistake). That call is a
safety-of-flight issue, IMHO - and not only for local club traffic,
but for any other aircraft passing by - and much more important than
reporting the tow height to the ground for billing purposes (which, in
our club, is not a tow pilot responsibility anyway - the member logs
it after the flight or gets charged a flat 3k ft tow...). As chief
tow pilot I don't want my tow pilots doing anything during their tow
flight that takes them away from clearing their flight path,
especially with lots of gliders milling around!

Kirk
66