What was found
AT FL180 STANDBY ALTIMETER READS 90 FEET ABOVE TOLERANCE CORRECTIVE ACTION: PERFORMED A GVI OF STANDBY PITOT TUBE, NO DAMAGE OR OBSTRUCTIONS NOTED, PER TASK 34-11-02-210-801A. PERFORMED TASK 34-11-02-100-801A PITOT-STATIC PROBE -DRAIN HOLE CLEANING. GAINED ACCESS AND BLEW NITROGEN THRU PITOT AND STATIC LINES BACK TO PROBE, NO DEBRIS COLLECTED. PERFORMED IESI FUNCTIONAL CHECK IN REF TO TASK 34-11-00-720-801A ALL ALTITUDES WITHIN TOLERANCE LEVELS OF TABLE 501.