Wednesday, April 15, 2009

Windy Day Flying

Yesterday, I flew up to Lincoln to visit an old friend. We had set up the trip the day before, and the forecast for the time was a nice day with partial clouds. Sure enough, when I got up yesterday it was a bright sunny day with a few scattered clouds. Unfortunately there was also a minor matter of wind.

For flying, we rely greatly on current weather observations at airports, called METARs. When I took off, the weather reports looked like this:

KRHV 141747Z 29015G25KT 10SM SCT040 12/02 A2995
KLHM 141910Z 29020G24KT 10SM SCT070 BKN080 OVC090 13/M03 A2981

For those unfamiliar with decoding these little gems, KRHV was the airport I was flying from and KLHM my destination. The second part is the date and time of the observation, and the third part is the wind. For this one it means that my winds taking off were from a 290 heading, and observed as 15 knots with gusts of up to 25 knots. The runway heading at RHV is 310, so this was about 20 degrees off runway heading.

Takeoff went fairly smoothly, I pulled the plane up into the air once the wheels felt light and immediately turned into the wind. Once off the ground we climbed FAST. We dodged a couple clouds at 4000' on our way up to cruise altitude (that would be the SCT040), and then settled in for a short, bumpy flight to the Lincoln airport.

The winds at Lincoln look pretty similar to RHV -- from 290, 20 knots with gusts to 24. However, the Lincoln runway heading is 330, which makes these winds a full 40 degrees off runway heading. For a 20 knot wind, that gives an effective crosswind of 13 knots.

On my first approach to the airport I did not set up well for the landing. I neglected to take the crosswind into account when turning from base to final, and so instead of turning out lined up with the runway, I did a big skidding turn that blew me past the runway and then to fight my way back into alignment. The approach stayed ugly all the way down to the runway, at which point I scratched the landing and went around to try again.

The second approach went much better. I turned earlier towards the runway, got myself lined up much better, and then transitioned into a good crosswind landing (right rudder, left bank) prior to touchdown. I also think the winds were lighter on the second approach.

Had a good lunch and chat with my friend, then headed back to the airport. For the return trip, I was looking at:

KLHM 142230Z AUTO 03016KT 10SM BKN100 13/M01 A2980

While the winds were lower, they were now perpendicular to the runway instead of at an angle, which didn't make my life any easier (effective crosswind 14 knots). I had to wait for a helicopter and a water bomber that were using the bad winds as good training to make a hole, then again made an uneventful takeoff.

The weather when I finally got back to Reid-Hillview was:

KRHV 142247Z 28017G25KT 10SM SCT040 15/01 A2993

Life hasn't gotten any better back here. I get myself lined up correctly the first time this time, end up touching down near the runway threshold and I am off the runway by taxiway Bravo without even braking hard (Alpha is at the beginning of the runway).

I have mixed feelings about this flight. On one hand, it was good training for dealing with high-wind conditions, and all my (completed) takeoffs and landings went well. On the other hand, I'm not sure if I should have been up in the air in the first place. The takeoff and landing at LHM were both close to the maximum crosswind for my plane (16 knots, I believe). My motivation to fly was about equal parts get-there-itis (I had cancelled on my friend twice before due to weather) and a desire to push the envelope out some on weather I was comfortable flying in.

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