Oh Ring!

Had a bit of an upset in the Tigercat on the way to Boeing Field the other day. Wings folded nicely on taxi (hint). Locked them in place. Run-up, no problem. About 1,000 psi. “Time to go” in a formation take-off with Carter and the Bearcat. The Museum of Flight was expecting us at 10:30 for their Centennial of Naval Aviation Day complete with three Hellcat aces. At 85 I pulled back (gently) on the stick to allow the nose wheel to lift. Then, a noise. Not just any noise. A noise that could be heard over Pratt & Whitney 2800 take-off power about three feet from both ears. It sounded as if I was sharing the cockpit with a cow and the cow had been shot. Hydraulics. Sure enough, the 1,000 psi before take-off now was zero. What seemed to rile the wounded cow was the lever intended for landing gear retraction. Gear still in place… question mark? I tried to keep my focus and said something to the tower in the downwind. My Bearcat formation partner checked beneath and reported that the main gear appeared to be 90-degrees to the fuselage. In other words, “down and locked.” I asked the tower to look for the pink color of hydraulic fluid on the white gear but none was visible. The navy blue color of the rest of the aircraft provided an impossible backdrop, so in the second circuit I asked my mate to continue to Boeing Field for our mission. There was nothing more he could do. One more circuit during which the conversation included “souls on board” and “fuel in minutes.” OK, so things aren’t going well in the cockpit and the tower gives you a little math problem. How many minutes are in an hour? I considered flying-off over two hours of fuel but realized that two empty drop tanks and large engines separated the runway from the wing fuel cells, so I asked for a landing clearance. Minimum air speed with no flaps. The flaps left for vacation with the landing gear. Touchdown revealed that the gear had not unlocked (thanks, Grumman) so the principal remaining challenge was to stop with no brakes. Not tough on a 9,000 foot runway. I could turn using differential power and made my way back to HFF without incident, but on the downhill slope of Kilo 7 our beloved B-25 appeared before me rather rapidly. Happily, the emergency hand pump allowed me to recover 200 psi of brakes momentarily, at which point I turned off the engines and allowed the ground crew to tow home the Tigercat in front of a parade of emergency vehicles. The culprit? A fifty-cent “O” ring in one of the wing-fold actuators. All the fluid had leaked. Wings that fold for landing gear is a bad trade…