ASHLAND, Wis. (AP) – Ashland County authorities say a La Crosse doctor and his brother were killed in a single-engine plane crash on Madeline Island.  Sheriff Mick Brennan identifies the victims as the pilot, 63-year-old Doctor Richard Renwick, and his brother, 58-year-old Bruce Renwick from Waunakee.  WXOW-TV reports Doctor Renwick was a physician in obstetrics and gynecology at Gundersen Health System. In a statement, Gundersen says Renwick “was an exceptional physician, but even more important, he was a wonderful friend and family man.”  The Piper Comanche went down south of a runway on the island in northwestern Wisconsin Saturday evening and became engulfed in flames.  A witness told sheriff’s investigators the pilot was trying to land the plane, then aborted the landing and turned to make a second approach before it went down.