Narrative:

After arriving at aircraft, first officer queried maintenance why there was excess air flow from the #1 engine. Maintenance subsequently turned off the APU bleed for approximately 1 min and turned back to 'on.' engine then did not rotate. Maintenance's explanation in doing so by turning off the APU bleed thus solves the problem and this is 'normal.' maintenance supervisor was then called out for further explanation. Maintenance supervisor stated that this to be 'normal,' claiming that if the APU bleed valve is actuated before engine air pressure (duct pressure) decreases, the engine bleed valve or prsov valve will remain open. Again maintenance supervisor stated this as 'normal operations' and he has seen this on 3 separate occasions. Maintenance supervisor said he would look into generating a bulletin or memo as to this condition. Upon arriving at destination, maintenance asked why engine was rotating. After further investigation and discussion, he claimed that the previous explanation from maintenance was not correct. He found that the 9TH stage high pressure valve to be sticking. He generated MEL #36-0 and wired the valve closed. A further explanation from maintenance stated that this is not a 'normal operating occurrence,' but as the system is designed, more of a nuisance. In conclusion, I am wondering if we should generate a memo for future reference on this condition. Is this in fact 'normal' or not?

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Original NASA ASRS Text

Title: A MEDIUM LARGE TRANSPORT WAS DISPATCHED IN NON COMPLIANCE WITH A L ENG PRESSURE REGULATOR AND SHUTOFF VALVE CHK VALVE FUNCTION FAILED ALLOWING THE ENG TO ROTATE WITH APU PNEUMATICS.

Narrative: AFTER ARRIVING AT ACFT, FO QUERIED MAINT WHY THERE WAS EXCESS AIR FLOW FROM THE #1 ENG. MAINT SUBSEQUENTLY TURNED OFF THE APU BLEED FOR APPROX 1 MIN AND TURNED BACK TO 'ON.' ENG THEN DID NOT ROTATE. MAINT'S EXPLANATION IN DOING SO BY TURNING OFF THE APU BLEED THUS SOLVES THE PROB AND THIS IS 'NORMAL.' MAINT SUPVR WAS THEN CALLED OUT FOR FURTHER EXPLANATION. MAINT SUPVR STATED THAT THIS TO BE 'NORMAL,' CLAIMING THAT IF THE APU BLEED VALVE IS ACTUATED BEFORE ENG AIR PRESSURE (DUCT PRESSURE) DECREASES, THE ENG BLEED VALVE OR PRSOV VALVE WILL REMAIN OPEN. AGAIN MAINT SUPVR STATED THIS AS 'NORMAL OPS' AND HE HAS SEEN THIS ON 3 SEPARATE OCCASIONS. MAINT SUPVR SAID HE WOULD LOOK INTO GENERATING A BULLETIN OR MEMO AS TO THIS CONDITION. UPON ARRIVING AT DEST, MAINT ASKED WHY ENG WAS ROTATING. AFTER FURTHER INVESTIGATION AND DISCUSSION, HE CLAIMED THAT THE PREVIOUS EXPLANATION FROM MAINT WAS NOT CORRECT. HE FOUND THAT THE 9TH STAGE HIGH PRESSURE VALVE TO BE STICKING. HE GENERATED MEL #36-0 AND WIRED THE VALVE CLOSED. A FURTHER EXPLANATION FROM MAINT STATED THAT THIS IS NOT A 'NORMAL OPERATING OCCURRENCE,' BUT AS THE SYS IS DESIGNED, MORE OF A NUISANCE. IN CONCLUSION, I AM WONDERING IF WE SHOULD GENERATE A MEMO FOR FUTURE REF ON THIS CONDITION. IS THIS IN FACT 'NORMAL' OR NOT?

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.