Ultramagic M-105 N30018 incident near Louisville, Colorado

Probable cause

The balloon's encounter with unforecast strong gusting wind, which resulted in a high-wind landing. Contributing to the accident was the National Weather Service's misjudgment of the timing and underestimation of the magnitude of the frontal boundary moving across the region.

NTSB analysis

The pilot reported he received the same weather forecast that other pilots flying that day had received and that the weather was "nice." About 30 minutes into the flight, the wind began to increase, so he briefed the passengers for a high-wind landing. As the balloon got closer to the surface, the wind started moving the balloon south, then southeast. The pilot landed the balloon in a field on the north side of a highway. The pilot reported that, during the landing, the balloon was accelerating, so he leveled off about 10 feet above the ground and then opened up the top of the envelope. The balloon solidly hit the ground and was dragged for about 100 feet before stopping.

A review of meteorological data available at the time of the preflight briefing indicated, in part, that wind from the west existed at 10 knots or less before takeoff. The National Weather Service (NWS) terminal area forecast expected easterly wind shifting to the northwest during the anticipated flight at 13 knots with wind from the north gusting to 23 knots after 1000 mountain daylight time. The NWS area forecast did not expect any high winds across Colorado. The NWS Aviation Forecast Center had no advisories current for low-level turbulence or high winds over Colorado surrounding the anticipated flight. However, shortly after takeoff a sudden increase in windspeed occurred across the region with wind gusts from 20 to 38 knots. The NWS misjudged the timing and underestimated the magnitude of the frontal boundary moving across the region. It is likely that, if the pilot had known about the gusting wind at the time of takeoff, he may not have chosen to fly that day.

Text from the NTSB. Open the NTSB docket for CEN13IA350 for the full record.