Crosswind Limit at a Narrow Strip
You hold a Recreational Pilot Certificate with a crosswind endorsement limited to 12 kt. The strip is 480 m of dry grass, 18 m wide, oriented 09/27. The current aerodrome forecast gives wind 140 degrees true at 14 kt gusting 22 kt, and the actual reported surface wind from the windsock is 150 degrees at 13 kt gusting 18 kt. Your aircraft has a demonstrated crosswind component of 15 kt. Density altitude is close to 2,800 ft. You are solo, with 55 minutes of fuel, and the only alternate is 25 minutes away with a similar grass surface. A pilot on the ground reports the gusts are rolling over the tree line on the north side and that the last two arrivals went around.
1. Compute the crosswind component for the reported surface wind and decide whether you may legally and safely land.
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The angle between runway 09 (090) and wind 150 is 60 degrees. Crosswind = 13 x sin 60 = 13 x 0.866 = about 11.3 kt steady, and for the gust 18 x 0.866 = about 15.6 kt.
Legally, the steady component of 11.3 kt is inside your 12 kt endorsement, but the gust component of 15.6 kt exceeds it. Because a gust is a wind you must be able to handle on touchdown, treat the gust value as the operative crosswind. That puts you outside your endorsement and also at the aircraft's demonstrated crosswind of 15 kt. The decision is a go-around or diversion, not a landing. Note also that the forecast 140/14G22 gives 12.1 kt steady and 19 kt gusting, so the trend is not improving.
2. Explain how the narrow 18 m strip and density altitude change your risk picture even if the wind moderated.
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An 18 m strip leaves very little room for drift on touchdown and for the roll-out after a bounced or crabbed arrival. A crosswind landing typically touches down on the upwind wheel first and then requires prompt into-wind aileron and rudder correction; on a narrow strip a small lateral error becomes a runway excursion or a strike on the edge markers. Density altitude near 2,800 ft raises true airspeed for the same indicated approach speed, lengthens the ground roll, and reduces climb performance for the go-around. Grass also adds rolling resistance and reduces braking effectiveness. Together these mean the effective margins for a 480 m strip are much smaller than the book figures suggest, so the decision should be more conservative than the bare crosswind number implies.
3. The pilot on the ground says the last two arrivals went around. How should that report change your plan?
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Reports of two go-arounds are direct evidence of wind shear or mechanical turbulence from the tree line, not just a steady crosswind. That means the wind at 50 ft may differ sharply from the windsock reading, so the computed 11 to 15 kt component understates the actual disturbance at the flare. A sensible plan is to hold overhead or divert to the alternate while fuel allows, and if you do attempt an approach, fly a stabilised approach with a committed go-around point, carry extra approach speed for the gusts, and expect a loss of airspeed on short final. With 55 minutes of fuel and a 25 minute alternate, you have one attempt at most before the diversion becomes mandatory rather than optional.