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First saw this on the Aviation Herald website.
When you lose either the Y or G hydraulics system, you need to turn off the PTU ( power transfer unit ) or you will overheat the other system and cause it to fail, which it did.
Loss of G + Y Hydraulics, is very serious on the A321.
No auto pilot, no reverse thrust, no flaps ( much faster landing speed ), no yaw damper, flight protections lost ( alternate law ), loss of spoilers, no anti skid ( much longer landing distance ) , loss of nose wheel steering .
Not sure I buy the reason why they never turned off the PTU.
Edit: They also had a “ avionics smoke “ caution.
Never heard of a landing so hard it resulted in the crew putting their oxygen mask on after.
Also, they already had the flaps extended when they lost the second hydraulic system which still allowed them to land with flaps versus had the dual hydraulics failure happened while in clean configuration.
https://www.flightglobal.com/safety...em-failures-after-hard-landing/154794.article
When you lose either the Y or G hydraulics system, you need to turn off the PTU ( power transfer unit ) or you will overheat the other system and cause it to fail, which it did.
Loss of G + Y Hydraulics, is very serious on the A321.
No auto pilot, no reverse thrust, no flaps ( much faster landing speed ), no yaw damper, flight protections lost ( alternate law ), loss of spoilers, no anti skid ( much longer landing distance ) , loss of nose wheel steering .
Not sure I buy the reason why they never turned off the PTU.
Edit: They also had a “ avionics smoke “ caution.
Never heard of a landing so hard it resulted in the crew putting their oxygen mask on after.
Also, they already had the flaps extended when they lost the second hydraulic system which still allowed them to land with flaps versus had the dual hydraulics failure happened while in clean configuration.
https://www.flightglobal.com/safety...em-failures-after-hard-landing/154794.article
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