Mountain Rescue Task with Confined Area and Weather Deterioration
You are tasked to recover an injured climber from a confined ridge at 2 800 ft elevation. The LZ is 15 m × 20 m with a 20° slope, surrounded by 25 m trees on three sides and a drop-off on the fourth. Surface wind is 15 kt gusting 25 kt, reported as across the ridge. Cloud base is 3 500 ft and lowering, with visibility 5 km in rain. Aircraft mass is 1 000 kg with a maximum sling load of 250 kg; the climber weighs 85 kg plus 20 kg of equipment. The nearest hospital helipad is 35 NM away with 8 km visibility. You have 1 h 40 min fuel remaining. The crew includes one paramedic and one winch operator.
1. Assess whether a landing, hover, or winch recovery is appropriate, and explain the performance and handling considerations.
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Recommended method: winch recovery from a hover, not a landing.
- Landing: The 20° slope exceeds the normal landing limit for most helicopters (typically 6–10°), and the 15 m × 20 m area with 25 m trees on three sides leaves little rotor clearance. A landing is not appropriate.
- Hover: A hover is feasible but the 15–25 kt gusting across-ridge wind creates turbulence and downdrafts on the lee side. The OGE hover power required at 2 800 ft with a 1 000 kg mass must be checked; the gust margin and density altitude reduce performance.
- Winch: Winching keeps the aircraft clear of the slope and trees, allows a controlled hoist of the 105 kg load, and permits a quick break-off if conditions worsen. The winch operator must manage the cable in the gusty wind and the pilot must maintain a stable hover reference.
Handling: Approach into wind if possible, use a high hover to stay above tree level, and brief a go-around. Monitor torque and TOT; if limits are approached, abort.
2. Decide whether to proceed given the weather trend and fuel state, and describe the abort criteria.
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Decision: proceed only with a strict time limit and clear abort criteria; otherwise hold or withdraw.
- Weather: Cloud base 3 500 ft is 700 ft above the ridge, but lowering cloud and 5 km rain visibility reduce the margin. If the cloud base falls below 3 200 ft or visibility below 3 km, the approach should be abandoned.
- Fuel: 1 h 40 min remaining. The round trip to the hospital is 35 NM each way, about 45 min at 90 kt, plus 20 min on scene and reserve. This leaves a thin margin; refuel or plan a closer facility if possible.
- Abort criteria: abort if the cloud base drops below 3 200 ft, visibility below 3 km, gusts exceed 30 kt, torque or TOT limits are approached, or the hover becomes unstable. Brief the crew on these before the approach.
- Judgement: The task is time-critical for the casualty, but the crew's safety is paramount. Proceed with a committed abort plan and keep ATC informed.