A320 one engine taxi.

[Citation2]

No need to wait until engine one spool down at the gate before switching off the Y ELec pump. PTU is inhibited with parking brake set.

[Amadis of Gaul]

Originally Posted by Citation2

No need to wait until engine one spool down at the gate before switching off the Y ELec pump. PTU is inhibited with parking brake set.

Indeed. Most Captains take the PB off after the chock signal, though. Hence, the commonplace "what's that noise?"

[Gryphon]

No need to wait until engine one spool down at the gate before switching off the Y ELec pump. PTU is inhibited with parking brake set.

if both engines master OFF (or both ON, but not the case), PTU Auto and diff press >500 psi, it will run independently of the park brake.

[Stone Cold II]

Runs every time I come onto stand after doing single engine taxi once engine one shut down and the parking brake is set.

[Citation2]

PTU will run during engine 1 shutdown , and not when parking brake is set with Y ELEC pump OFF .

[vilas]

Citation2
Any reference for parking brake and PTU connection? Because during ENG1 start it comes on as a test.

[Gryphon]

PTU will run during engine 1 shutdown

Right, cause both engine master OFF (as long as diff HYD press > 500 psi)

and not when parking brake is set with Y ELEC pump OFF .

Right again, because 1 engine master ON, the other OFF and Park brake ON and Nose wheel steering not in towing position

[Gryphon]

Any reference for parking brake and PTU connection? Because during ENG1 start it comes on as a test.

Yes, because both engines master ON (as long as diff HYD press > 500 psi and PTU sw in auto)

FCOM DSC-29-10-20 PTU (logic)

[vilas]

Gryphon
Thanks.

[flightplan]

And a cant understand what are the difficulties in PTU running for several seconds? Is it so important to avoid it?