Narrative:

Flight crew arrived to operate flight as a maintenance ferry. The aircraft was powered down upon crew arrival. After powering up the aircraft and APU; the crew performed a normal preflight along with all first flight of the day checks; which were all normal. The aircraft was left unattended with the APU running for approximately 15 mins while the ferry permit was being corrected and while the crew discussed the general condition of the aircraft with maintenance control. Upon re-entering the flight deck; it was noted that there were 2 new caution messages displayed: APU btl low and hydraulic system 1 high temperature. A mechanic was subsequently called out to the aircraft and along with the flight crew the decision was made to shut the aircraft down as there had obviously been an APU bottle discharge and; therefore; the APU was without fire protection. The mechanic inspected the aft equipment bay to find a metal pipe located between the left pack and heat exchanger to be loose and venting bleed air. Hot bleed air from this leak had set off the APU fire bottle and heated the #1 hydraulic system to approximately 99 degrees C; which in turn expanded the hydraulic fluid to more than 100% capacity and caused a small amount of venting of the fluid overboard. Several attempts were made to reinstall this pipe but it would not fit; indicating that it may have been the incorrect part for that location. Eventually; it was agreed that the entire left side of the bleed air system would have to be shut off for flight; which was accomplished by starting the engines with the APU; shutting down the APU; and operating only the right side 10TH stage bleed air and the right air conditioning pack. After re-filing of the flight plan and a rechk of all paperwork involved; the aircraft was then ferried without incident. The aircraft had been placed in maintenance due to a lightning strike. It is possible that this damage could have been a direct result of that strike; or it may have occurred due to human error and incorrect installation of the part. Had the event occurred in the air; significant damage may have occurred. A thorough preflight and the EICAS system prevented the aircraft from ever being in danger. The current aircraft logbook had no record of work performed on this part that failed; but it is possible that it was incorrectly installed beforehand. It is also possible that the lightning strike the aircraft sustained caused this damage. If it is because of improper installation; then a more thorough investigation of maintenance work performed on the aircraft would have prevented this situation.

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Original NASA ASRS Text

Title: A CRJ-200 FLT CREW PREFLIGHTING FOR A MAINTENANCE FERRY FOUND SEVERAL DISCREPANCIES INVOLVING THE APU AND A/C PACK PLUMBING.

Narrative: FLT CREW ARRIVED TO OPERATE FLT AS A MAINT FERRY. THE ACFT WAS POWERED DOWN UPON CREW ARR. AFTER POWERING UP THE ACFT AND APU; THE CREW PERFORMED A NORMAL PREFLT ALONG WITH ALL FIRST FLT OF THE DAY CHKS; WHICH WERE ALL NORMAL. THE ACFT WAS LEFT UNATTENDED WITH THE APU RUNNING FOR APPROX 15 MINS WHILE THE FERRY PERMIT WAS BEING CORRECTED AND WHILE THE CREW DISCUSSED THE GENERAL CONDITION OF THE ACFT WITH MAINT CTL. UPON RE-ENTERING THE FLT DECK; IT WAS NOTED THAT THERE WERE 2 NEW CAUTION MESSAGES DISPLAYED: APU BTL LOW AND HYD SYS 1 HIGH TEMP. A MECH WAS SUBSEQUENTLY CALLED OUT TO THE ACFT AND ALONG WITH THE FLT CREW THE DECISION WAS MADE TO SHUT THE ACFT DOWN AS THERE HAD OBVIOUSLY BEEN AN APU BOTTLE DISCHARGE AND; THEREFORE; THE APU WAS WITHOUT FIRE PROTECTION. THE MECH INSPECTED THE AFT EQUIP BAY TO FIND A METAL PIPE LOCATED BTWN THE L PACK AND HEAT EXCHANGER TO BE LOOSE AND VENTING BLEED AIR. HOT BLEED AIR FROM THIS LEAK HAD SET OFF THE APU FIRE BOTTLE AND HEATED THE #1 HYD SYS TO APPROX 99 DEGS C; WHICH IN TURN EXPANDED THE HYD FLUID TO MORE THAN 100% CAPACITY AND CAUSED A SMALL AMOUNT OF VENTING OF THE FLUID OVERBOARD. SEVERAL ATTEMPTS WERE MADE TO REINSTALL THIS PIPE BUT IT WOULD NOT FIT; INDICATING THAT IT MAY HAVE BEEN THE INCORRECT PART FOR THAT LOCATION. EVENTUALLY; IT WAS AGREED THAT THE ENTIRE L SIDE OF THE BLEED AIR SYS WOULD HAVE TO BE SHUT OFF FOR FLT; WHICH WAS ACCOMPLISHED BY STARTING THE ENGS WITH THE APU; SHUTTING DOWN THE APU; AND OPERATING ONLY THE R SIDE 10TH STAGE BLEED AIR AND THE R AIR CONDITIONING PACK. AFTER RE-FILING OF THE FLT PLAN AND A RECHK OF ALL PAPERWORK INVOLVED; THE ACFT WAS THEN FERRIED WITHOUT INCIDENT. THE ACFT HAD BEEN PLACED IN MAINT DUE TO A LIGHTNING STRIKE. IT IS POSSIBLE THAT THIS DAMAGE COULD HAVE BEEN A DIRECT RESULT OF THAT STRIKE; OR IT MAY HAVE OCCURRED DUE TO HUMAN ERROR AND INCORRECT INSTALLATION OF THE PART. HAD THE EVENT OCCURRED IN THE AIR; SIGNIFICANT DAMAGE MAY HAVE OCCURRED. A THOROUGH PREFLT AND THE EICAS SYS PREVENTED THE ACFT FROM EVER BEING IN DANGER. THE CURRENT ACFT LOGBOOK HAD NO RECORD OF WORK PERFORMED ON THIS PART THAT FAILED; BUT IT IS POSSIBLE THAT IT WAS INCORRECTLY INSTALLED BEFOREHAND. IT IS ALSO POSSIBLE THAT THE LIGHTNING STRIKE THE ACFT SUSTAINED CAUSED THIS DAMAGE. IF IT IS BECAUSE OF IMPROPER INSTALLATION; THEN A MORE THOROUGH INVESTIGATION OF MAINT WORK PERFORMED ON THE ACFT WOULD HAVE PREVENTED THIS SITUATION.

Data retrieved from NASA's ASRS site as of May 2009 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.