• Aircraft
  • Aircraft N23721 Hydraulic Systems Failure

N23721 had a hydraulic system failure on flight from IAD to SEA. Made an emergency landing at ORD. Pilots had to manually crank the flaps into position. I think they were using cranks for the ailerons and rudder as well because there was considerable response time lag. The plane would roll and I would watch the ailerons slowly move to compensate. Even after all wheels were on the ground, the plane felt difficult to control... was wobbling as if it were making sharp turns.

The only thing that appeared to "just work" was the landing gear.

Do these planes have any contingency in place for the scenario where the hydraulic fluid is completely lost? I know it has redundant pumps but if the hydraulic fluid is being lost, then what good are the pumps?

I'm guessing the wet spots under the plane in the photo are hydraulic fluid puddles...

those wet spots are under the engines, and yes engines have hydraulic components, but they are usually self-suffucient and not reliant on the rest of the hydraulic system of the aircraft for operation. those spots could have been there from years of aircraft being in that spot and having normal engine oil leaks. thats my guess.

those wet spots are under the engines, and yes engines have hydraulic components, but they are usually self-suffucient and not reliant on the rest of the hydraulic system of the aircraft for operation. those spots could have been there from years of aircraft being in that spot and having normal engine oil leaks. thats my guess.

No, not those spots. The white blob by the guy wearing the yellow jacket is what I'm referring to. Its a puddle of liquid, although its not clear in the photo. There is another puddle between the rear wheels. Both puddles are under the fuselage.

The engines were never a problem (or at least didn't appear so in flight). The problem was with all the hydraulics for all of the control surfaces.