Descent below MDA -- what would you do?

"Roy Smith" wrote in message
...

I probably should know this, but now that I (re-)read the above, I see
that there's several ways to parse that sentence with respect to B and C
airspace:

1) Only the inner cylinder that touches the surface is the surface area,
i.e. SVFR is not available in the outer rings of B/C airspace.

2) The boundaries of the surface area are exactly the same (vertical and
lateral) as the B/C airspace. This is what I had always assumed.

3) The surface area includes all the airspace from the edge of the
outermost ring projected down to the surface. This would be extremely
illogical, but it is one possible parsing.

Which is correct?


Prior to airspace reclassification there were control zones within and
distinct from ARSAs and TCAs and SVFR was clearly limited to just the
control zone. If SVFR was now available within the entire Class B or Class
C airspace it would mean a major change that was not mentioned or discussed
during reclassification.

FAR 91.155(c) states, "Except as provided in FAR 91.157, no person may
operate an aircraft beneath the ceiling under VFR within the lateral
boundaries of controlled airspace designated to the surface for an airport
when the ceiling is less than 1,000 feet." Since we're only concerned with
the portion within 1000 feet of the surface scenario 2) would be eliminated.



Is there such a thing as B, C, or D airspace in the US which is not
"designated for an airport"?


I don't know of any Class B or C like that, but there has been some odd
Class D
airspace areas.

One of them was Pearson Field in Vancouver, WA, about seven miles northeast
of Portland International. Pearson had Class D airspace from the surface
to the overlying Portland Class C airspace. Vancouver had no control tower
and was the only airport in the Class D surface area. Vancouver now has a
Class E surface area.

Another one is adjacent to the Seattle Class B surface area on the west
side. This one still exists, you can view it at the following link:

http://makeashorterlink.com/?F27B2314B


A third one was south of the El Toro MCAS which is now closed, the Class D
airspace apparently was dropped when the base closed. Part of this one
didn't even touch the surface. I have old charts which depict this area, I
can post some images if you're interested.

"Steven P. McNicoll" wrote:

A third one was south of the El Toro MCAS which is now closed, the Class D
airspace apparently was dropped when the base closed. Part of this one
didn't even touch the surface. I have old charts which depict this area, I
can post some images if you're interested.

When El Toro closed KSNA lost half of its Class C airspace because of the way
the rules were made piecemeal. It took over a year to get that airspace
modified and redesignated to provide the Class C protection for KSNA that used
to be there when El Toro was operating.

Airspace designations are only as good as the regional airspace staffs
responsible for them.

Steven,
FAR 91.155(c) explicitly refers to "controlled airspace" i.e. airspace
classified as E,D,C,B, and A. Since it is possible to be in E airspace
without being near an airport, it is possible to operate under Special
VFR as long as the requirements in FAR 91.157 are met. Moreover,
ground based weather reporting is NOT required for Special VFR and FAR
91.157 (c)(2) explains what to do if "..ground visibility is not
reported..".

"gman" wrote in message
oups.com...

Steven,
FAR 91.155(c) explicitly refers to "controlled airspace" i.e. airspace
classified as E,D,C,B, and A. Since it is possible to be in E airspace
without being near an airport, it is possible to operate under Special
VFR as long as the requirements in FAR 91.157 are met.


Yes, it's possible to be in Class E airspace without being near an airport,
but I don't think it's possible to be "within the airspace contained by the
upward extension of the lateral boundaries of the controlled airspace
designated to the surface for an airport" without being near an airport. Do
you?



Moreover, ground based weather reporting is NOT required for Special VFR
and FAR
91.157 (c)(2) explains what to do if "..ground visibility is not
reported..".


FAR 91.157(c)(1) says no person may take off or land an aircraft (other than
a helicopter) under special VFR unless ground visibility is at least 1
statute mile. If ground visibility isn't being reported it's because the
AWOS/ASOS is on the fritz or the weather observer overslept.

I'm sorry for dragging this thing on but part (a) of the paragraph you
quoted (FAR 91.155) says that if the weather conditions (visibility,
and cloud clearance) are below the prescribed minimums, you cannot
"operate an aircraft under VFR" unless you go Special VFR. The weather
minimums in paragraph 91.155(a) only refer to classes of airspace not
only to those around an airport.

You are correct about FAR 91.155(c,d). However, this rule is in
addition to the other parts of section 91.155.

Since the original poster was on a GPS approach, and most certainly in
controlled airspace, he could have requested a Special VFR clearance
and landed as long as he operated clear of clouds and flight visibility
was greater than 3SM. Even though the airport does not have an
official weather reporting systems, the FARs authorize the pilot to use
his/her own judgment in determining visibility.

"gman" wrote in message
oups.com...

I'm sorry for dragging this thing on but part (a) of the paragraph you
quoted (FAR 91.155) says that if the weather conditions (visibility,
and cloud clearance) are below the prescribed minimums, you cannot
"operate an aircraft under VFR" unless you go Special VFR. The weather
minimums in paragraph 91.155(a) only refer to classes of airspace not
only to those around an airport.

You are correct about FAR 91.155(c,d). However, this rule is in
addition to the other parts of section 91.155.

Since the original poster was on a GPS approach, and most certainly in
controlled airspace, he could have requested a Special VFR clearance
and landed as long as he operated clear of clouds and flight visibility
was greater than 3SM. Even though the airport does not have an
official weather reporting systems, the FARs authorize the pilot to use
his/her own judgment in determining visibility.


Since the original poster told us there was no weather reporting at the
destination airport we can conclude there is no surface area because weather
reporting is required to establish a surface area. Since SVFR exists only
in a surface area we can conclude that SVFR was not available even if he had
requested it.

But FAR 91.155(c) says: "_EXCEPT_ as provided in =A791.157, no person
may operate an aircraft beneath the ceiling under VFR within the
lateral boundaries of controlled airspace designated to the surface for
an airport...." That means if you flying under 91.157 (i.e. Special
VFR) you need not comply with 91.155.

"gman" wrote in message
oups.com...

But FAR 91.155(c) says: "_EXCEPT_ as provided in §91.157, no person
may operate an aircraft beneath the ceiling under VFR within the
lateral boundaries of controlled airspace designated to the surface for
an airport...." That means if you flying under 91.157 (i.e. Special
VFR) you need not comply with 91.155.


Where can you fly under FAR 91.157?

Michael wrote:

You know from experience that this is a difficult
airport to spot even in good VFR because it blends in with the
surrounding terrain.

Sure it does. But if you know where to look, you can just see it
outlined in the haze.

Continuing your descent
below the MDA, but staying above the VNAV glideslope it technically not
legal, but seems like a "no harm, no foul" kind of violation.


You pays your money and you takes your chance.

Let's throw "legal" about the window because it's not really relevant.

This reminds me of something my CFII told me when we did our first ILS
to real minimums. "I'm not telling you to go below minimums, because
it's not legal, but if you just keep those needles absolutely nailed,
sooner or later you're going to crack it up right on that spot on the
runway."

This has little to do with legality because if you land fine no one can
ever be the wiser, and if you get it wrong, you can discuss the FARs
with Saint Peter. You've constructed a hypothetical scenario where
descending below minimums looks like a completely practical decision.
Having done it once, do you make a habit of it?

Search for descent below MDA and you will see many stories of pilots
who presumably thought they had their s--t together, as well as quite a
few who clearly were going into seriously unexplored territory. What we
don't know are how many pilots have violated the letter of the law by
25, 50, or 500 feet, and come out just fine. And don't even try to
pretend that following the FARs to the letter guarantees a safe
outcome, either. Flying IFR in your typical single involves taking more
than a few perfectly legal risks. There's a continuum between "Happy
landing" and "No survivors" and going for a peek is simply moving you
closer to the latter. How much? Read some of those accident reports and
compare.

Personally, would I do it? No. I'm a low-time IFR pilot and don't have
all the equipment you do. Ask me again how I feel in a few hundred
hours.

-cwk.

In article .com,
wrote:

This reminds me of something my CFII told me when we did our first ILS
to real minimums. "I'm not telling you to go below minimums, because
it's not legal, but if you just keep those needles absolutely nailed,
sooner or later you're going to crack it up right on that spot on the
runway."

Might, except the glideslope is not guarenteed below something like
100'. You would, at least, crash on the airport.