KERRVILLE, Texas (AP) — Witnesses say they heard the engine of a small plane sputtering and saw its tail dragging just before it crashed in Central Texas, killing all six people on board.

The Beechcraft BE58 crashed Monday morning as it approached Kerrville Municipal Airport, about 70 miles (110 kilometers) northwest of San Antonio.

The Texas Department of Public Safety says Jeffrey C. Weiss was piloting the plane. The plane’s co-owners say Weiss regularly volunteered to fly sick people from around the country to hospitals in Dallas and Houston.

DPS identified the passengers killed as: Houston landscape architect Marc Teppesen; his associate Mark Scioneaux; Houston architect Scott Reagan Miller; and Houston real estate investor Stuart Kensinger and his wife Angela Kensinger.