"Interesting" wind yesterday

As many may know, we set records here in Iowa yesterday, hitting 73 degrees
in Iowa City. It felt great!

The winds in the afternoon started to kick up pretty good, as a cold front
approached from the northwest. On our way back from brunch in Lone Rock, WI
(where we ran into this group's own Jim Burns, figuratively speaking. We
actually passed on the taxiway...) the wind was humming along at about 40
knots, right on the nose. It was smooth at 6500 feet, though, so Mary and
the kids were content to nap all the way home.

Iowa City AWOS was reporting 20 gusts to 26, but right down Rwy 25. As I
entered the pattern, however, it became very apparent that the winds at
pattern altitude were markedly different from the reported surface winds,
with a very strong southerly component that was pushing me in too close on
downwind.

As I turned from base to final, the unexpectedly strong wind had me bent out
of shape pretty good, but I managed to wrestle the runway back into
alignment without entering the coffin-corner of cross controlling.
Nevertheless, I was amazed to find that it was taking full left aileron and
right rudder to keep the runway in the windshield. This wind was clearly
NOT down the runway.

Asking Mary to get AWOS for me, the mechanical man was still reporting winds
at 240 -- perfect for Rwy 25. As I cursed the stupid AWOS equipment --
which was clearly malfunctioning (or so I thought) -- I told the kids to
hang on for a wild ride.

They weren't disappointed. On short final, it felt as if someone had kicked
up on the left wing from below with all their might, and we banked hard
(toward our hotel!) away from the runway. We were low, and slow, and things
didn't look good, but just as quickly as you can say it, I was able to right
us, and the wind was suddenly and instantly right down the runway.

Surprisingly, despite the wild approach, I continued my unexplained streak
of perfect landings, causing nary a squeak. Only difference was, this time
I was slightly out of breath, and I had a death-grip on the yoke... ;-)

Talk about wind shear. There was a nearly 90 degree difference in the wind
direction at MAYBE 500 feet (or less) off the ground. And both wind
"streams" were whistling right along, too.

Now today it's 35 degrees, and dropping like a stone -- with winds of well
over 30 knots.

Gotta love the Midwest in late winter!
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

The combination of [...] and that great looking paint job
left little doubt as to who it could be!

He painted his =airplane= purple??

Jose
--
Math is a game. The object of the game is to figure out the rules.
for Email, make the obvious change in the address.

The front must have been approaching Iowa and northern IL faster than it was
here in Wisconsin. We stopped at Adams 63C on the way home for 32 gallons
of cheap $2.32 100 LL. On the way from LNR to 63C we did a "speed run" just
to check the Aztec's performance. Using the KLN 94, it calculated the winds
at 3500 ft to be from 200 at 14, surface winds were 240 at 6. 26" and 2400
RPMs gave us a TAS of 200mph, just shy of the always optimistic book figure
of 205mph.

The rest of the afternoon at STE winds were 240 at 6. Lots of planes out in
the nice weather, even a Luscumbe practicing crosswind landings. Later in
the evening it must have picked up, because a friend of mine reported flying
north from Prairie Du Chien in his C170 with a 150kt ground speed. Now it's
34011G22 and temps dropped from 53 yesterday to 27 now and still falling.
Rain, sleet, and snow all mixed. Spring in Wisconsin is spelled
SwPiRnItNeGr, because every other day is one or the other.

I was happy to see Jay and Mary taxi up in the Pathfinder and almost wished
we would have had the "slower" waitress so we could have met before we
cranked up the Aztec. The combination of Mary's voice on the radio, two
kids in the back seat, Jay with his camera, and that great looking paint job
left little doubt as to who it could be!

Jim

"Jay Honeck" wrote in message
news:OUZWd.42901$r55.23167@attbi_s52...
As many may know, we set records here in Iowa yesterday, hitting 73
degrees in Iowa City. It felt great!

The winds in the afternoon started to kick up pretty good, as a cold front
approached from the northwest. On our way back from brunch in Lone Rock,
WI (where we ran into this group's own Jim Burns, figuratively speaking.
We actually passed on the taxiway...) the wind was humming along at about
40 knots, right on the nose. It was smooth at 6500 feet, though, so Mary
and the kids were content to nap all the way home.

Iowa City AWOS was reporting 20 gusts to 26, but right down Rwy 25. As I
entered the pattern, however, it became very apparent that the winds at
pattern altitude were markedly different from the reported surface winds,
with a very strong southerly component that was pushing me in too close on
downwind.

As I turned from base to final, the unexpectedly strong wind had me bent
out of shape pretty good, but I managed to wrestle the runway back into
alignment without entering the coffin-corner of cross controlling.
Nevertheless, I was amazed to find that it was taking full left aileron
and right rudder to keep the runway in the windshield. This wind was
clearly NOT down the runway.

Asking Mary to get AWOS for me, the mechanical man was still reporting
winds at 240 -- perfect for Rwy 25. As I cursed the stupid AWOS
equipment -- which was clearly malfunctioning (or so I thought) -- I told
the kids to hang on for a wild ride.

They weren't disappointed. On short final, it felt as if someone had
kicked up on the left wing from below with all their might, and we banked
hard (toward our hotel!) away from the runway. We were low, and slow, and
things didn't look good, but just as quickly as you can say it, I was able
to right us, and the wind was suddenly and instantly right down the
runway.

Surprisingly, despite the wild approach, I continued my unexplained streak
of perfect landings, causing nary a squeak. Only difference was, this
time I was slightly out of breath, and I had a death-grip on the yoke...
;-)

Talk about wind shear. There was a nearly 90 degree difference in the
wind direction at MAYBE 500 feet (or less) off the ground. And both wind
"streams" were whistling right along, too.

Now today it's 35 degrees, and dropping like a stone -- with winds of well
over 30 knots.

Gotta love the Midwest in late winter!
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"


In NV, I remember flying along in smooth air with 130kts of wind at 19,000'
and hearing the AWOS saying "wind calm". You knew you were probably in for
a beating somewhere during the descent. The area had frequent inversions at
night and the wind would go from high speed to dead calm in a few hundred
vertical feet. I also experienced (over UT) winds from the east at 120kts
at FL290 and from the west at 25kts at FL250. I reported this and it wasn't
long before all the eastbound airliners were down at FL250. I wouldn't have
thought it possible before seeing it for myself. I always thought that
winds just filled low pressure areas from high pressure areas but
apparently, it is more complicated.

Mike
MU-2

it was a weird day (and night).
I was flying on the UW MedFlight Augusta 109 late Saturday night, early
Sunday am this weekend and on a flight to Mauston, and then later to
Viroqua, we were showing only 95-100 knots heading to the NW from
Madison.
On the way back, with a patient on board, we were doing about 205
knots! Which was a blessing with a sick patient on board, keeps the
time to a minimum.
The shear factor wasn't as big of a deal overnight, which is also a
blessing because the approach to the UW helipad is like flying into a
canyon. And now we have a crane on top of the hospital to worry
about...

Ryan Wubben
Madison, WI

Jay Honeck wrote:

[cut]
As I turned from base to final, the unexpectedly strong wind had me bent out
of shape pretty good, but I managed to wrestle the runway back into
alignment without entering the coffin-corner of cross controlling.
[cut]

What is a coffin-corner and how does one get into it in the pattern?

Milen Lazarov wrote:

Jay Honeck wrote:

As I turned from base to final, the unexpectedly strong wind had me
bent out of shape pretty good, but I managed to wrestle the runway
back into alignment without entering the coffin-corner of cross
controlling.

What is a coffin-corner and how does one get into it in the pattern?

Jay frivolously used that well defined term completely wrong, presumably
just because it sounds good. (A tactic which some journalists use, too,
especially when they write about aviation...) You never get into the
coffin corner at pattern altitude.

The stall speed is constant with indicated airspeed, while Vne is
constant with true airspeed (acually, it decreases somewhat at high
altitudes). So there is a point, at very high altitudes, where Vs meets
Vne. This point is called the coffin corner, because you can't escape
from it (except by descending): You can't slow down (stall) nor
accelerate (Vne).

Stefan

What is a coffin-corner and how does one get into it in the pattern?

The "coffin-corner" is where you end up when the wind is blowing you
out from the runway on your base-to-final turn.

Your instinct is to tighten the turn in an effort to keep the runway
aligned, and maybe help it along with some rudder. This can be
disastrous at slow speeds while close to the ground, since a stall/spin
can develop quickly, and you won't have sufficient altitude to recover.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Coffin Corner, Deadmans Corner: The turn from base leg to final leg on a
landing approach. If the pilot has overflown the runway centerline and
attempts to roll back to the runway centerline adverse yaw will tend to
point the nose of the airplane in the opposite direction of the turn, a
natural reaction will be to use rudder to point the nose at the runway.
When this doesn't work the pilot may increase the bank in the same
direction. As the airspeed decays, the he incorrectly applies more rudder
in the direction of the turn creating a slow rolling uncoordinated skidding
turn close to the ground. Roll combined with Yaw in the direction of the
roll with airspeed dropping is a great recipe for a spin. The fact that
this situation is close to the ground makes the spin nearly unrecoverable.

Jim

I'll agree with Stefan that this term gets mixed usage. What Stefan refers
to is mainly a consideration for high altitude aircraft. The U2 is the
plane that instantly comes to mind. Think about pulling back, stall...
Think about pushing forward Vne.... not much room in between.

What I refered to in my response, I generally refer to as the Deadman's
Corner, it instills the seriousness of proper airspeed control,
coordination, and patience when teaching primary students proper landing
patterns.

Jim