Narrative:

Aircraft had maintenance write up for right hydraulic pressure over limit. Gauge was swapped but there was no change -- decision made to change transmitter in wheel. Mechanic advised not to use hydraulic pump but did not place placard on pump switch nor pull and collar pump circuit breaker. After a period of time a mechanic knocked on the right side of the aircraft and signalled for hydraulic pressure to be turned on, shortly afterward the mechanic ran into the cockpit and instructed us to turn the switch off, the mechanic in the wheel-well had been sprayed by hydraulic fluid in the face. We secured the pump and notified ramp tower that he had been injured and needed medical assistance. We then went out to the ramp to see if we could help.

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Original NASA ASRS Text

Title: MD80 FLC ACTIVATED THE HYD SYS DURING MAINT ACTIVITY. MECH INJURED WHEN HWY FLUID SPRAYED IN FACE.

Narrative: ACFT HAD MAINT WRITE UP FOR R HYD PRESSURE OVER LIMIT. GAUGE WAS SWAPPED BUT THERE WAS NO CHANGE -- DECISION MADE TO CHANGE XMITTER IN WHEEL. MECH ADVISED NOT TO USE HYD PUMP BUT DID NOT PLACE PLACARD ON PUMP SWITCH NOR PULL AND COLLAR PUMP CIRCUIT BREAKER. AFTER A PERIOD OF TIME A MECH KNOCKED ON THE R SIDE OF THE ACFT AND SIGNALLED FOR HYD PRESSURE TO BE TURNED ON, SHORTLY AFTERWARD THE MECH RAN INTO THE COCKPIT AND INSTRUCTED US TO TURN THE SWITCH OFF, THE MECH IN THE WHEEL-WELL HAD BEEN SPRAYED BY HYD FLUID IN THE FACE. WE SECURED THE PUMP AND NOTIFIED RAMP TWR THAT HE HAD BEEN INJURED AND NEEDED MEDICAL ASSISTANCE. WE THEN WENT OUT TO THE RAMP TO SEE IF WE COULD HELP.

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.