IFR test question

Having trouble with an IFR test question;
It reads,
What is the minimum increase in opacity of the surface based layer at
Fredericton (YFC), in order for it to constitude a ceiling?
METAR CYFC 132100Z 260010KT 2SM -RA BR BKN090 08/07 A2953 RMK
FG5SC1 SLP994

Choices:
a) none, it alreadi constitudes a ceiling
b) 2/8
c) 3/8
d) 1/8

The answer is c.
Anyone know why?

On Jan 20, 1:57 pm, "Markus" wrote:
Having trouble with an IFR test question;
It reads,
What is the minimum increase in opacity of the surface based layer at
Fredericton (YFC), in order for it to constitude a ceiling?
METAR CYFC 132100Z 260010KT 2SM -RA BR BKN090 08/07 A2953 RMK
FG5SC1 SLP994

Choices:
a) none, it alreadi constitudes a ceiling
b) 2/8
c) 3/8
d) 1/8

The answer is c.
Anyone know why?

3/8 + 5/8 (broken layer) = 8/8 (ceiling)

Longworth wrote:
On Jan 20, 1:57 pm, "Markus" wrote:
Having trouble with an IFR test question;
It reads,
What is the minimum increase in opacity of the surface based layer at
Fredericton (YFC), in order for it to constitude a ceiling?
METAR CYFC 132100Z 260010KT 2SM -RA BR BKN090 08/07 A2953 RMK
FG5SC1 SLP994

Choices:
a) none, it alreadi constitudes a ceiling
b) 2/8
c) 3/8
d) 1/8

The answer is c.
Anyone know why?

3/8 + 5/8 (broken layer) = 8/8 (ceiling)
Thanks very much...it was a 2-part question, and I couldn't figure out
the connection.
I do now...
Cheers, Longworth!

The answer is c.
Anyone know why?
3/8 + 5/8 (broken layer) = 8/8 (ceiling)
Thanks very much...it was a 2-part question, and I couldn't figure out
the connection.
I do now...

Things must be different in Canada. In the US, a ceiling is the
lowest layer designated (other than thin) broken or overcast

Markus wrote
Longworth wrote:
3/8 + 5/8 (broken layer) = 8/8 (ceiling)

Thanks very much...it was a 2-part question,
and I couldn't figure out the connection.

I wouldn't be too sure about that answer... this is the
definition of "ceiling" from FAR Part 1:

Ceiling means the height above the earth's surface of the
lowest layer of clouds or obscuring phenomena that is
reported as “broken”, “overcast”, or “obscuration”, and not
classified as “thin” or “partial”.

And from AC 00-45E, Aviation Weather Services

Table 2-5 Reportable Contractions for Sky Cover
Reportable Contractions
Meaning - Summation - Amount
*SKC or CLR Clear 0 or 0 below 12,000
FEW Few 0 but 2/8
SCT Scattered 3/8-4/8
BKN Broken 5/8-7/8
OVC Overcast 8/8
VV Vertical Visibility (indefinite ceiling) 8/8
*SKC will be reported at manual stations. The abbreviation
CLR shall be used at automated stations when no clouds below
12,000 feet are detected.
Note: For aviation purposes, the ceiling is defined as the
height (AGL) of the lowest broken or overcast layer aloft or
vertical visibility into an obscuration.


Partial Obscurations
The amount of obscuration is reported in the body of the METAR
when the sky is partially obscured by a surface-based phenomenon
by indicating the amount of obscuration as FEW, SCT, or BKN followed
with three zeros (000). The type of obscuring phenomenon is stated in the
Remarks element and precedes the amount of obscuration and three zeros. For
example, if fog is hiding 1/8 to 2/8 of the sky, it will be coded in the
body of the METAR as “FEW000.” Because the fog is partially obscuring the
sky, a remark is required. (See Figure 2-5.)


The Remark in your example doesn't seem to fit any of the examples given
in AC 00-45E.

Here is the url for the AC

http://www.faa.gov/about/office_org/...offices/afs/af
s400/awsac/media/sec02.pdf

Bob Moore

Bob,

I may be wrong but I believe the OP is Canadian. Maybe different "up
there?"

Jay B

Markus wrote

Having trouble with an IFR test question;

Whoops!! I missed that the question came from Canada.

Sorry

Bob Moore

In the remarks section, it says "FG5" which means the obscuring
phenomenon is 5/8 fog. For an obscuring phenomenon to be considered a
ceiling it needs to be 8/8. Therefore the answer is c because 5/8 + 3/8
= 8/8.

John

Markus wrote:

Having trouble with an IFR test question;
It reads,
What is the minimum increase in opacity of the surface based layer at
Fredericton (YFC), in order for it to constitude a ceiling?
METAR CYFC 132100Z 260010KT 2SM -RA BR BKN090 08/07 A2953 RMK
FG5SC1 SLP994

Choices:
a) none, it alreadi constitudes a ceiling
b) 2/8
c) 3/8
d) 1/8

The answer is c.
Anyone know why?

On Jan 20, 6:36 pm, The Visitor
wrote:
In the remarks section, it says "FG5" which means the obscuring
phenomenon is 5/8 fog. For an obscuring phenomenon to be considered a
ceiling it needs to be 8/8. Therefore the answer is c because 5/8 + 3/8
= 8/8.

John


John,
I did not know that it was a Canadian test question. You are
correct that FG5 means 5/8 fog according to this document

http://tinyurl.com/yvzubl

If not uncommon that in a multiple choice test, you can get the
right answer for the wrong reason ;-)

While I was typing my reply the reply above was posted, so I'll just
add, "He's right." In U.S. METAR code, I believe the remark would be,
"FG BKN000". An additional 3/8 of ground-based obscuration would be
needed to make the sky totally obscured; under the METAR rules that
would constitute a ceiling. (Under the old Airways code rules we
called it "vertical visibility" rather than a ceiling if the sky was
totally obscured.)