AeroCare Medical Transport System, Inc.

WHILE ENROUTE, THE LOW OIL PRESSURE LIGHT BEGAN TO FLICKER. IDENTIFIED VIA THE OIL PRESSURE GAUGE THAT THE NO. 2 ENGINE OIL PRESSURE WAS FLUCTUATING BETWEEN 30-40 PSI. REFERENCED THE ABNORMAL PROCEDURES CHECKLIST FOR FURTHER GUIDANCE ON ADDRESSING THE ANNUNCIATION WHICH RECOMMENDED A POWER REDUCTION OF THE AFFECTED ENGINE AND TO CONTINUE TO MONITOR THE OIL PRESSURE AND TEMPERATURE. THE NO. 2 OIL TEMP READ APPROXIMATELY 40 DEGREES HIGHER THAN THE NO. 1 WHICH PROVIDED CONFIRMATION THAT AN OIL LEAK WAS LIKELY. THE OIL PRESSURE CONTINUED TO SLOWLY DROP. WE HAD DECIDED THAT IF THE OIL PRESSURE DROPPED TO 25 PSI OR LOWER, WE WOULD SHUTDOWN THE NO. 2 ENGINE AS A PRECAUTIONARY MEASURE (AS RECOMMENDED BY THE CHECKLIST). SEVERAL MINUTES LATER THE OIL PRESSURE DROPPED TO 25 PSI, AND THE LOW OIL PRESSURE ANNUNCIATOR LIGHT ILLUMINATED. THE FIRST OFFICER DECLARED AN EMERGENCY AND REQUESTED A DIVERSION. WHILE IN THE DESCENT WE SUCCESSFULLY CONDUCTED THE INFLIGHT ENGINE SHUTDOWN AND SECURE CHECKLIST FOR THE NO. 2 ENGINE. UPON INSPECTION OF THE AIRCRAFT ON THE GROUND AFTER SHUTDOWN, A LARGE AMOUNT OF OIL COULD BE SEEN STREAKED ACROSS THE NO. 2 ENGINE COWLING AND DRIPPING FROM THE GANG DRAIN ONTO THE WING FLAP. THE DIRECTOR OF MAINTENANCE AND DIRECTOR OF OPERATIONS WERE CONTACTED AND INFORMED OF THE ISSUES. THE AIRCRAFT WAS WRITTEN UP FOR THE EVENTS DESCRIBED ABOVE AND SUBSEQUENTLY GROUNDED. THE OIL CAP ORING WAS FOUND TO BE CUT. WE RECOMMEND REPLACING THE O-RING EVERY 150/250 HR INSPECTION.

ACFT DEPARTED, EN ROUTE THE FL180 CHECKS WERE COMPLETED, ALL NORMAL. AT FL340, THE CREW NOTICED THE CABIN WAS AT 8,000 FEET AND CLIMBING. TURNED THE CABIN PRESSURE CONTROL TO MANUAL AND TRIED TO DRIVE THE CABIN DOWN, WITH NO SUCCESS. THE CABIN CLIMBED TO 9,000 FEET AND THE LT EMERGENCY PRESSURIZATION VALVE OPENED AS IT SHOULD. THEY DESCENDED, THE EMERGENCY PRESSURIZATION RESET AFTER THE CABIN DESCENDED. MX INVESTIGATED THE ISSUE, AND FOUND THAT THE PRESSURE REGULATOR THAT SUPPLIES THE FLOW CONTROL VALVE, IT`S REF PRESSURE WAS NOT REGULATING THE PRESSURE CORRECTLY. THE PRESSURE IS SUPPOSED TO 15 PSI +-2, BUT WENT AS HIGH AS 28 PSI DURING GROUND RUNS. THE HIGHER THE REF, THE MORE THE FLOW CONTROL VALVE DRIVES TO CLOSED, STARVING THE CABIN OF INFLOW. NO RECOMMENDATION OR PREVENTION.

AFTER LEVEL OFF, HEARD A BANG, NOTICED AC STARTED TO DUTCH ROLL AND AP DISCONNECTED. INITIATED EMER DESCENT AND AC FLIGHT STABILIZED. NOTICED AFCS YAW CIRCUIT BREAKER WAS POPPED AND PRI AND SEC YAW DAMPER WAS INOPERATIVE, CREW ELECTED TO NOT RESET THE CIRCUIT BREAKER, SO AS NOT TO INDUCE FURTHER COMPLICATIONS, RETURN TO DEPARTURE. MX REPRODUCED DISCREPANCIES. FOUND 3 BROKEN OR PARTIALLY BROKEN WIRES AT THE PRI YAW DAMPER COMPUTER CONNECTOR NR AP200. THE CAUSE OF THE BROKEN WIRES IS DUE TO AGING ACFT ISSUES. LACK OF STRAIN ON THE PRIMARY YAW DAMPER CONNECTOR FROM ORIGINAL PRODUCTION ALLOWING WIRES TO BE FLEXED CAUSING WORK HARDENING AND SUBSEQUENT BREAKAGE.

WHEN SELECTING "GEAR DOWN" ON APPROACH TO DESTINATION AIRPORT THERE WAS NO RT DOWNLOCK "GREEN" ANNUNCIATOR. LANDING GEAR WAS CYCLED 5 TIMES. THE 5TH TIME SHOWED "3 GREEN" AND ACFT WAS LANDED WITHOUT INCIDENT. ACFT WAS JACKED AND GEAR WAS SWUNG. FOUND INTERMITTENT RT MAIN GEAR DOWN LOCK SWITCH. WIRING WAS BROKEN INTERNALLY RT AT THE SWITCH POTTING. REPLACED SWITCH WITH NEW PART. OPS CHECK SATISFACTORY AND ACFT RELEASED FOR SERVICE.

AFTER TAKEOFF, THE FLIGHT CREW NOTICED AIRFRAME VIBRATION. ACFT LANDED AT THE CLOSEST AIRPORT WITHOUT INCIDENT. A VISUAL INSPECTION OF THE RT COWLING SHOWED THAT THE FWD OTBD 2 LATCHES WERE UNLATCHED AND THE AFT OTBD LATCH WAS SECURED. THE UPPER AND LOWER COWLING SUSTAINED MINOR DAMAGE. CAUSE WAS A FAILURE TO SECURE THE TWO FWD LATCHES AFTER CHECKING ENGINE OIL. PROCEDURES FOR ENSUING A THOROUGH PREFLIGHT INSPECTION SHOULD BE REINFORCED AND ALL PERSONNEL SHOULD FOLLOW A COMPLETE PREFLIGHT INSPECTION AFTER THE ACFT HAS BEEN DISTURBED FOR ANY REASON PRIOR TO FLIGHT. (K)

DURING A MX HIGH SPEED TAXI CHECK SMOKE NOTICED OUT OF PILOTS SIDE WINDOW. ACFT STOPPED ON RUNWAY AND CABIN DOOR OPENED AT WHICH TIME A FIRE WAS FOUND ON LT MLG WHEEL AREA. ACFT SHUTDOWN AND FIRE EXTINGUISHED. PRIOR TO THE TAXI TEST A FULL BRAKE AND ANTI-SKID FUNCTIONAL CHECK IAW MM PERFORMED WITH SATISFACTORY RESULTS. ORIGINAL SQUAWK WAS A SLIGHT PULL TO LT DURING LANDING WHEN TRANSITIONING THRU SLOWER SPEEDS. NOSE WHEEL STEERING NOT ARMED WHEN PULL WAS NOTICED. RT BRAKES & WHEELS SUSTAINED EXCESSIVE HEATING WITH NO DEFLATION OR FIRE. ALL BRAKING COMPONENTS WERE REMOVED FROM ACFT AND SENT TO MFG FOR EVALUATION. PROBABLE CAUSE OF FIRE WAS OVERHEATING OF BRAKES. NO TURNAROUND LIMITATION EXIST FOR THIS ACFT. IT IS SUGGESTED OPERATORS USE A TURNAROUND TIME LIMITATION TO ALLOW SUFFICIENT COOLING BETWEEN MEDIUM TO HIGH ENERGY BRAKING APPLICATIONS.

IMMEDIATELY FOLLOWING TAKEOFF, THE FLIGHT CREW OBSERVED AN ODOROUS VAPOR IN THE CABIN. FOLLOWING CONTACT WITH ATC AND REDUCING CABIN AIR INFLOW, THE CREW IMMEDIATELY RETURNED TO THE DEPARTURE AIRPORT UNEVENTFULLY. THE SMOKE OR VAPOR ACCUMULATION BEGAN DISSIPATING FOLLOWING ENGINE POWER REDUCTION. THIS INFORMATION WILL BE UPDATED AS FURTHER INFORMATION IS ACQUIRED.