The Block 45 major avionics update is forecast to prolong the life of the KC-135 into its 80th or 90th year
On Aug. 25, 2017, the Iowa Air National Guard’s 185th Air Refueling Wing in Sioux City, Iowa received its first KC-135 aircraft converted with the newest digital avionics cockpit instruments known as the Block 45 upgrade.
As explained by Master Sgt. Vincent De Groot, 185th Air Refueling Wing, in the article Iowa Air Guard’s 185th ARW receives 1st block 45 aircraft equipped with major avionics upgrade, the instrument panel replacement modification replaces most of the remaining analog gages in the cockpit of the aging KC-135 with new instrumentation, coupled with a modern LCD display.
Avionics such as the radio altimeter, auto-pilot, digital flight director and other components associated with these systems in the aircraft were all replaced.
Noteworthy the 185th’s first modernized KC-135 spent 60 days at Tinker Air Force Base (AFB) in Oklahoma before pilots from the Iowa ANG retrieved the aircraft in order to bring it home to Sioux City.
According to Lt. Col. Shawn Streck, 185th ARW Maintenance Commander, the instruments that are replaced as part of the process at Tinker are original equipment from when the aircraft first rolled off the Boeing assembly line in the late 1950’s.

“The jet that we are bringing home was built in 1958 and most of the instrumentation is original to the aircraft. This upgrade will put our aircraft on-par with its civilian counterpart,” said Streck.
Over the course of the next 12 months the 185th Air Refueling Wing in Sioux City is scheduled to have five of its KC-135’s equipped with the new cockpit avionics.
“Our maintainers take amazingly good care of these aircraft, and they are maintaining them at a level that they will be able to fly until 2040 or 2050,” Streck said.
Representatives from Iowa based Rockwell Collins Aviation, to whom the Block 45 contract was awarded, said the $105 million-dollar Air Force wide program is expected to keep the fleet of around 400 KC-135’s viable for many years to come.
Just last year the KC-135 celebrated its 60th birthday. According to Streck the newest major avionics update is forecast to prolong the life of the mid-air refueling aircraft into its 80th or 90th year.

Photo credit: Master Sgt. Vincent De Groot 185th ARW PA / U.S. Air National Guard
Artwork courtesy of AircraftProfilePrints.com