Onawa Flying Service BE35 N53GM crashes near Sioux City after departing EAA AirVenture at KOSH

ADS-B data reviewed by SkyMeter shows N53GM, a Beechcraft Bonanza BE35 operated by Onawa Flying Service Inc, departed Wittman Regional Airport (KOSH) in Oshkosh, Wisconsin at 10:52 a.m. local time (15:52 UTC) on July 26, 2026, heading west at approximately 252 degrees. The aircraft climbed through the departure phase, reaching a peak altitude of 6,952 feet MSL, and then settled into a long westbound cruise at roughly 6,794 to 6,840 feet at ground speeds between 145 and 175 knots. SkyMeter's analysis also flagged a TFR penetration event at the start of the track near KOSH. According to WLUK, the pilot was returning from EAA AirVenture and was killed in a crash near Sioux City, Iowa.

The recorded ADS-B track shows the aircraft maintaining near-level cruise on a heading of approximately 254 to 255 degrees for roughly an hour and a half before beginning a gradual descent around 1:08 p.m. local time. The descent steepened considerably in the final minutes of the track: from about 6,660 feet at 1:08 p.m., the aircraft descended through 4,160 feet by approximately 1:14 p.m. local time, with vertical speeds reaching as steep as 2,220 feet per minute during that interval. The track ends at 1:16 p.m. local time at 2,700 feet MSL, with the aircraft still on a heading of 259 degrees at 167 knots and descending.

The full recorded flight, spanning about two hours and 24 minutes of ADS-B coverage, can be replayed on SkyMeter.