No, there is a system blocking valve that is closing the retract line with sys B pressure below 2000PSI. The PTU will not overpressure that (Source AMM manual). Think of the PTU as a back up for auto slats. During an engine # 2 failure auto slats may not react quick enough to counter a high AOA scenario, so the PTU jumps in to help extend the slats to the full extend position. This may be the case during an immediate turn after an engine failure. The QRH does not tell you to retract the leading edge devices with the help of the PTU.
Last edited by repulo; 23rd May 2016 at 04:45.