Heading home to Spearfish, SD after golfing earlier in the day in SE Colorado (La Hunta) the winds were building and as I flew over the last half of the Black Hills, I noticed my plane was flying cocked a bit as I continued a northern heading. Groundspeed was dropping as the very strong side wind continued to increase. It wasnt anything unexpected, I checked the weather while in La Hunta and I knew there were winds above normal forecast and my 496 weather satellite feed kept me informed of wind speed and direction. I also knew winds in Rapid City were reasonable from watching the 496 during my flight so an out was always nearby.
20 miles south of the Spearfish airport I listened to ATIS report direct crosswind guts of 70mph. I called Unicom to confirm; sure enough the airport manager confirmed wicked winds, no error in the ATIS report.
I began my descent from 10,500 and at the time the turbulence wasn’t too bad. I’d flown the last hour with the autopilot off because it was rough enough I didn’t want to over work the servos. Descending into Spearfish is often rough since the airport is surrounded by the Black Hills. I should have just diverted to Sturgis or Rapid City before descending but I wanted to get down and see what things looked like.
When I dropped to 1,500 agl a few miles SE of the airport the turbulence was very significant. It was obvious I wasn’t going to land in Spearfish. I called the Unicom in Sturgis and they reported light winds, hard to believe since its downwind from Spearfish and only 18 miles east. As I turned to make Sturgis my new destination the turbulence was too much to handle.
Winds at the time of my descent into Spearfish around 4:30PM Sunday 1-27-08 had been clocked at 101 mph and a semi truck had been blown off the hi-way a mile from the airport. This information gained after the fact helped explain why I was being thrown all over the place.
I could no longer go with the wind toward Sturgis, it was too dangerous. I turned back against the wind and climbed to 8,000 trying to rise above the worst of the turbulence. I headed northwest during the climb toward the Belle Fourche airport, which is 12 miles north of Spearfish. Although the winds in Belle were very high, which was apparent from all the dirt blowing, I descended anyway to 4500 to look at the windsock and get a feel for the turbulence closer to the ground. Belle Fourche is 3200 feet and has no ATIS and no one answered their Unicom frequency. Winds were straight out of the west and blowing as bad as Spearfish. Turbulence was rough as well.
I climbed back to 8000 mostly into the wind since I felt I had more control heading into the wind. The lower speed against the wind made the turbulence more tolerable. I knew I needed to get away from the Black Hills because when I turned with the wind again Id be like a kite and I wanted to be over the prairie. When I reached 8,000 I reduced power to 2000 rpm and 18 manifold pressure and turned with the wind, within 20 seconds I had a ground speed of 220 mph.
I continued to talk to the Sturgis Unicom; they were reporting winds of only 10 mph, straight from the east. I said are you sure, Im being blown east like a kite. He confirmed winds straight down the runway from the east and he told me to land on 11 if and when I could get there. I told him I’d continue northeast with the wind till I could come into Sturgis from the northeast. While I was being blown to the east it was rough but tolerable, I was flying with almost no power over 200 mph as I continued east of Belle Fourche 30 miles.
When I got north of Sturgis I tried to begin a southerly heading to the Sturgis airport. I turned south but the winds continued to blow me east and I couldn’t get much headway toward the south. Although I was feeling a little nauseous, I was feeling better now because I knew once I got down and near the Sturgis airport, landing would be no problem. I wanted to head to the airport against the wind since I felt more in control going against the wind. I was looking forward to being on the ground, this had gone on to long.
After reaching a point about 35 miles northeast of Sturgis at 5,000 agl I started a sharp descent while heading southwest and finally made up some ground and as I got to 1,000 agl, I was finally within five miles to the northeast of the Sturgis airport.
When I landed on 11 the wind was in my face and the sock was straight out blowing 20 mph. I was very happy to be on the ground. Everything in the plane was thrown around and I hit the ceiling once so hard my headset flew off in spite of my belt being tight.
It was good to be in contact with the local Sturgis Unicom since he gave me hope if I could get to him, I’d be able to get landed. Trying to avoid getting to nauseated was a big problem since Id been in this turbulent mess for about 40 minutes.
I’ve landed at 150 different airports and the Black Hills continue to be the worst weather I’ve faced. The Rockies and the Big Horns and the Wyoming prairie can generate some real wind speeds and turbulence. If you fly in this country you kind of know what to expect and every once in a while it hands it to you in spades, today was one of those days. Seven years ago a straight-line wind destroyed all the hangars at the Spearfish airport. I often face rough turbulence descending into Spearfish, this was the roughest, at least we have all nice new hangars.