wool@oracle.UUCP (Chris Wooldridge) (11/04/85)
Living and flying as I do in the cloudy NW, I'm always interested in hearing
about experiences pilots have with weather ... in my opinion, a subject which
is neglected a lot in pilot education. It's a touchy, personal subject with
a lot of pilots - at least in the guise of the go/nogo decision. You get your
briefing, try to visualize what it's going to look like. Get too ambitious
and you may put yourself into a tight (yes, let's face it, even fatal)
situation; be too cautious and you're sitting on the ground a lot, never
learning what the impossible looks like, what your limits are. The go/nogo
is nerve wracking enough for VFR pilots (who always worry, justifiably, about
getting into IMC) but actually even more thorny for IFR pilots who don't have
the "it's not VFR" legal excuse to justify not flying in their own minds.
I'm interested in any personal experiences or observations which any of you
are willing to share on this subject. For my part, I can contribute a spooky
Halloween flight which illustrates a couple of maxims: "weather is where you
find it, not where FSS says it is" and, "the 2C/1000' lapse rule doesn't always
apply".
I was returning to Seattle from the bay area with a business stop in Redmond,
Ore. I fly this route a lot, mostly on the west side of the Cascades, even
in winter, in an Mooney with oxygen, turbocharger & spare fuel tank. Ice
is the main worry; I avoid it when I can, get out of it immediately when I'm
in it, fly high (flight levels if necessary) to stay on top. The briefing
I got from OAK FSS sounded like the usual winter one; solid IFR from the
Siskiyous north, icing & turb to FL180 all the way to Seattle. I flew VFR
up to Red Bluff (it's always such a pain trying to depart the bay area IFR)
and picked up a VFR on top clearance just before starting the climb for the
Siskiyous.
As I past Mt. Shasta the turbocharger breathed its last; I decided to continue
anyway based on the look of things ahead. Turned out to work ok, I was able
to stay between layers most of the time picking up light rime when I popped
the infrequent cloud. The weather wasn't near as bad as forecast ... during
the VOR approach into RDM I noted passing the freezing level at 7,800.
Departing RDM in the dark, I got a briefing from FSS. All sorts of real
nastiness between RDM and BFI, confirmed by PIREP's. But I had it figured
out; I'd get a 7,000' altitude from ATC (wrong for direction of flight, but...)
till I got to Portland, then 6,000 to Seattle. Winds Aloft looked like I
would be within a degree or so of the freezing level. Departed RDM, got the
7,000 assigned, headed for the Dalles in clouds & precip with OAT exactly 0C.
Then ATC called - for traffic, climb and maintain 8,000. I requested vectors
around traffic and 7,000. They said vectors would require 8,000 for terrain
anyway. So I went up to 8,000 and started watching things carefully. The
OAT stayed at 0C - no ice! And I was occasionally on top. Very curious.
Stayed at 8,000 into Portland and started up to Seattle, wondering how long
this could last as I headed north. Finally decided enough, went down to
the 6,000' MEA - and the OAT STAYED AT 0C! In fact, it stayed at 0C all the
way to Seattle through the vectors for the ILS down to about 2,500, when
there was a big lurch in the airplane and the OAT jumped to 43F.
It's a known fact that atmospheric instability causes variations in the
2C/1000' rule, but consider this - this discontinuity covered several
hundred miles, both sides of a major mountain range. There was some
early moderate turb, but most was light. The airmass was forecast as
stable. There was a warm front but it was well offshore. Some steep
north/south pressure gradients which were giving me good headwinds.
A spooky Halloween ...
--
Chris Wooldridge
Oracle Corporation
1100 206th Avenue, N.E.
Redmond, Wa. 98053
(206) 868-1985 {ihnp4!muuxl,hplabs}!oracle!wool marcum@sun.uucp (Alan Marcum) (11/11/85)
In article <137@oracle.UUCP> wool@oracle.UUCP (Chris Wooldridge) writes: >Living and flying as I do in the cloudy NW, I'm always interested in hearing >about experiences pilots have with weather ... in my opinion, a subject which >is neglected a lot in pilot education. It's a touchy, personal subject with >a lot of pilots - at least in the guise of the go/nogo decision. In a book I read a while ago, Dick Collins recommended changing the 'go/nogo' decision to a 'start/continue' decision. The 'continue' portion is constantly re-examined as the flight progresses. I've found this oulook on weather flying to be very valuable -- it helps break the 'well, here I am, and I decided to do it, so I bettger do it' syndrome. -- Alan M. Marcum Sun Microsystems, Technical Consulting ...!{dual,ihnp4}!sun!nescorna!marcum Mountain View, California