Wind Shear / Your Thoughts

AKBill

AKBill

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AKBill
Took a short flight today. Weather has not been real good lately and I thought I would take a short flight before the next front comes thru.

Airport winds were 5kts. Forecasted winds were 15 to 20kt. Flew down Chatham Strait and encountered strong winds/wind shear.

Cruse speed was 120mph at 2000ft, all of a sudden vertical speed was 600fpm and IAS jumped to 140mph. That lasted for about 10 seconds, then speed dropped to 100mph with -400fpm. It was bumpy but not what I would call moderate. I was flying next to an island with peaks of 3500-4000ft.

I made a left turn to head toward the center of the channel and things calmed down. IAS was 120mph and ground speed was 75mph.

Glad I did not have a passenger with me. Something I have not encountered a lot of.

Comments/Thanks
 
Glad everything worked out okay. Wind shear can be a dangerous phenomenon to light aircraft!
 
I’d bet on some form of orographic up/downdrafts...and with what sounds like 40 mph or so down the channel, some venturi effect as well.
 
It happens...I wouldn’t worry about it too much. Keep an eye on the winds aloft forecasts. Wind sheer is the biggest problem when there is low level wind shear due to decoupling or a frontal passage. I’ve never hit wind sheer in cruise that was worrisome...just uncomfortable. Now mountain turbulence is a different story.
 
ircphoenix said:
Got caught in the rotor once. I was very unhappy for a period of time.
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Nice understatement!

I used to fly wave in gliders and now encounter it pretty regularly on one of my frequent routes. The thing that irks me is how the autopilot reacts versus what I know to be optimal way to get through it.

The AP does what is necessary for IFR ops - it keeps a constant altitude by slowing in the sink and speeding up in the lift. That insures that you will spend more time in down air and the least time in the up air. In the Appalachian waves I encounter that can take my airspeed from 110 through 175 with very noticeable deck angle changes. It’s just so inefficient!

The optimal way is to pull (slow down and climb) in the up air and ‘push’ (speed up and sink faster) in the down air. A clearance for a 2000’ band would do the trick. Perhaps not best of passengers but still....

Glider guiders know what I mean here.


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Keep the wings level, let the altitude vary with the drafts. Ride it out and search for smoother air. Moving your focus further ahead will make it less uncomfortable.
 
Sounds like a little minor mountain wave/mechanical turbulence activity. I hit the occasional mechanical turbulence several times in the southeast area when I was there. I did a charter into Petersburg once. Wind calm on the runway but sure not calm in the air above the sound until I got above the highest terrain.
 
Zeldman said:
Sounds like a little minor mountain wave/mechanical turbulence activity. I hit the occasional mechanical turbulence several times in the southeast area when I was there. I did a charter into Petersburg once. Wind calm on the runway but sure not calm in the air above the sound until I got above the highest terrain.
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FYI, glider people actually meet once a year in Petersburg to fly the mountain waves there. It is a particularly good place for them. A good NW wind increasing with altitude does the trick.


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It's like every day the wind is out of the west on final approach to 35 at KVGC! :) Orographic turbulence can get your attention anytime you are downwind of a hill, ridge or obstruction when the wind is blowing. The worst I experienced was a severe temorary downdraft off Piseco Mountain at the Piseco airport. Only time I ever aborted a takeoff, and glad I did. There was ZERO climb available after liftoff. Two minutes later all was well and I departed without incident. Gotta pay attention when the wind is honking.
 
Zeldman said:
Sounds like a little minor mountain wave/mechanical turbulence activity. I hit the occasional mechanical turbulence several times in the southeast area when I was there. I did a charter into Petersburg once. Wind calm on the runway but sure not calm in the air above the sound until I got above the highest terrain.[/QUOTE]

I thought climbing but decided to move to the center of the channel instead. Was at Hawk Inlet heading for Barlo Cove and did not want to conflict with any IFR traffic using that approach.
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