CHI01LA221 · Piper PA-30

The pilot said they were dispatched on a routine cloud-seeding mission at 2250. All flight operations through takeoff were normal. The pilot said that after passing through 50 feet agl, the airplane would not climb. The pilot said he verified power on both engines and airspeed of 120 mph. He brought the gear up and the climb performance improved slightly. The pilot said, "The maximum altitude achieved was just below 3,100 feet msl (100 feet agl), as the rapidly increasing downdrafts from the invisible microburst soon overpowered any climb performance, and quickly pushed the aircraft downward as the VSI (vertical speed indicator) indication transitioned from slightly positive to 150+ fpm (feet per minute) negative." The pilot said the airplane's engines were at maximum power when they struck a tree approximately 1 mile from the departure end of the runway. The pilot said he pitched the nose up in preparation for the ground impact. The airplane broke free of the tree. The pilot said he leveled the wings, lowered the nose slightly to keep his speed up, and reduced the throttles to idle. The airplane touched down about 3 to 5 seconds after their collision with the tree. The pilot said that 1 minute after the crash, heavy rain from a thunderstorm occurred. An examination of the airplane revealed no anomalies. At 2253, the weather reported at Hettinger, North Dakota (HEI), 34 miles east of BPP, was few clouds at 8,000 feet agl, a broken ceiling of 12,000 feet agl, 10 miles visibility with light rain, winds 100 degrees at 9 knots, temperature 74 degrees Fahrenheit (F), dew point 68 degrees F, altimeter 29.80 inches of Mercury, and remarks, lighting in the distance west and northwest, rain began at 2245. At 2301, the weather reported at HEI was scattered clouds at 9,000 feet agl, a broken ceiling of 12,000 feet agl, 10 miles visibility with light thunderstorms and rain, winds 330 variable 030 at 8 knots, and remarks, lighting in the distance west to north, thunderstorms began at 2255. At 2322, the weather reported at HEI was 3,500 scattered, 10,000 broken, 12,000 overcast, 10 miles visibility with light thunderstorms and rain, winds 030 degrees at 32 knots, gusts to 41 knots, and remarks, peak wind 030 degrees at 41 knots recorded at 2317, wind shift at 2302, lightning in the distance all quadrants.

Verbatim NTSB analysis and probable cause from the NTSB dataset