James Donald “Jim” Behnke, 70, of Washington, MO, died Thursday October 9, 2025, at Barnes Hospital in St. Louis after a courageous battle with Polycystic Kidney Disease. He was born July 26, 1955, in Kewanee, IL, the son of Donald and JoAnn (Grothe) Behnke. He married Jan Brinkmann on July 5, 1997 in St. Charles, MO. She survives as does his daughter Megan (Chris) Barlow of Des Peres, MO, his mother JoAnn Behnke of Kewanee, IL, two sisters Susan Behnke of San Clemente, CA, and Kathleen Nibeck of Northbrook, IL. Also surviving are three grandchildren - Rosemary, Lucy, and Charlotte Barlow, as well as nieces, nephews, cousins, and extended family. He was preceded in death by his father, Donald W. Behnke.

Jim graduated from Wethersfield High School with the class of 1973. He attended the University of Illinois Urbana-Champaign and earned a B.S. degree in Aeronautical and Astronautical Engineering in 1977. He was employed as a Structural Test Engineer at McDonell-Douglas in St. Louis from 1978-1997 and as a Structural Test Team Lead for Boeing in St. Louis from 1997 until his retirement in 2015.

Jim was a certified private pilot, built a Rutan Quickie airplane with his buddies, and had a lifelong passion for airplanes and flying. Jim had a warm and welcoming personality and never met a stranger. He always signed off “Keep Smiling”!

Visitation will be held from 3:00 PM to 7:00 PM on Monday, October 13, 2025, at Oltmann Funeral Home in Washington, MO. Funeral services will be held at 10:30 AM on Tuesday, October 14, 2025, at Immanuel Lutheran Church in Washington, MO with visitation an hour before the service. The Rev. Craig Wehmeyer will officiate. Burial will follow in the church cemetery.

Memorials can be made in Jim’s name to the Polycystic Kidney Foundation (https://pkdcure.org/give/) or a charity of the donor’s choice.