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KC-135Q
The SR-71 would be a very short-ranged aircraft were it not for air refueling, limited to around 2,000 NM. Multiple air refuelings extended the range of the aircraft to the limits of crew endurance. Many missions have exceeded 12,000 NM. Forward basing of the SR-71 and KC-135Q tankers permitted faster response, shorter range, shorter duration missions, fewer air refuelings, and greater overall efficiency.
KC-135Q crews and their aircraft were unique from the rest of the Air Force in several ways. As explained by Col. Richard H. Graham, a former Blackbird pilot, in his book SR-71 The Complete Illustrated History of THE BLACKBIRD The World’s Highest, Fastest Plane. their aircrews in fact were the only one certified in Blackbird’s specific radio-silent rendezvous procedures, and their boom operators were the only ones qualified to refuel the SR-71. The Q-model tankers had special plumbing between their fuel tanks, allowing them to transfer JP-4 and JP-7 fuel between various tanks. Their engine could burn transfer JP-4 or JP-7 fuel. If the SR-71 landed somewhere JP-7 fuel was not available, the Q-model tankers flew in with the fuel and, through the use of transfer hoses on the ground, were able to refuel the SR-71.
No story on the SR-71 would be complete without an understanding and appreciation of just how valuable the KC-135Q model tankers and their crews were to the successful and safe completion of every mission.
Blackbird pilots up to the challenge
The SR-71, needed to be refueled approximately every hour. Refueling was tricky, but SR-71 pilots were always up to the challenge, as former Blackbird driver David Peters explained to me;
‘Refueling …it’s just so much more complex. Especially with the 135’s [The Blackbird could refuel from KC-10s too]. Things like 99% of us had to run the seat all the way to the bottom to have an angle to see the director lights.
‘This put you in a very awkward position on the stick with no support.
‘Probably the most dangerous part was transferring from one tanker to the next.
‘He was struggling to keep up his 300 kts and we had to slow down to drop back to him. It could get really dicey especially in weather. Sometimes even had to use the equipment to facilitate a second join up. I used either afterburner [AB] if the weather was good and I wouldn’t need the defogger.
SR-71 pilot using one Afterburner during Aerial Refueling
‘The technique I taught was to lift the throttle over the stop at the same time running in rudder trim into the AB engine. And a little bank to straighten it out. If you did it right it all came together and you never changed positions.’
Peters concludes;
‘As soon as you lifted the one throttle to AB you would switch to the other throttle for fore and aft corrections.’
Be sure to check out Linda Sheffield Miller (Col Richard (Butch) Sheffield’s daughter, Col. Sheffield was an SR-71 Reconnaissance Systems Officer) Twitter X Page Habubrats SR-71, Instagram Page SR71Habubrats and Facebook Page Born into the Wilde Blue Yonder Habubrats for awesome Blackbird’s photos and stories.
Photo credit: U.S. Air Force
