RR INVESTMENTS INC

WHILE IN ROUTE THE R/H ENGINE OIL PRESSURE BEGAN TO FLUCTUATE. OIL PRESSURE CONTINUED TO DROP. PILOTS ELECTED TO PROCEED WITH AN IN INFLIGHT SHUTDOWN OF THE # TWO ENGINE S/N PCE-CF0412.

AIRCRAFT WAS ESTABLISHED ON FINAL APPROACH TO KADS WHEN THE CREW NOTICED AN "ACRID ELECTRICAL BURNING SMELL" AND ASSOCIATED EYE BURNING. THE PIC REPORTED THAT HE DID NOT SEE ANY SMOKE OR FIRE. THE CREW DECLARED AN EMERGENCY WITH ATC, REQUESTED ARFF ASSISTANCE, AND COMPLETED THE APPLICABLE AFM PROCEDURES FOR LANDING. THE AIRCRAFT LANDED WITHOUT INCIDENT AND TAXIED TO THE RAMP UNDER THE WATCH ARFF. THE PASSENGERS AND CREW DEPLANED NORMALLY. THE AIRCRAFT HAS BEEN PLACED IN "G" STATUS PENDING MAINTENANCE.

THE PIC REPORTED THAT DURING THE TURN FROM BASE TO FINAL ON APPROACH INTO KATL, THEY EXTENDED FINAL FLAPS FOR LANDING. SOON AFTER THE FLAP EXTENSION, THEY BEGAN TO HEAR A SOUND THEY DESCRIBED AS A CLUNKING SOUND” EVERY FEW SECONDS. AFTER THE 4TH OR 5TH SUCH SOUND, THEY RECEIVED A “PIT TIRM” ANNUNCIATOR ON THE PFD. THE PIC ELECTED TO DISCONNECT THE AUTOPILOT. AFTER AUTOPILOT DISCONNECTION, THE PIC WAS UNABLE TO TRIM THE AIRCRAFT ELECTRICALLY OR MANUALLY. AS A PRECAUTION, THE PIC ELECTED TO DECLARE AN EMERGENCY WITH ATC. THE AIRCRAFT WAS CONFIGURED, TRIMMED AND CONTROLLABLE FOR LANDING SO, THEY ELECTED TO CONTINUE WITH THE APPROACH. THE AIRCRAFT CONTINUED THE APPROACH AND LANDED UNEVENTFULLY. MAINTENANCE TESTED THE TRIM SYSTEM AND FOUND IT TO BE OPERATING AS PER THE MAINTENANCE MANUAL INSTRUCTIONS. ENGINEERING REQUESTED THE ACTUATING UNIT BE LUBRICATED, WHICH WAS PERFORMED. BRIDAL CABLE TENSIONS WERE ALSO CHECKED. NO DEFECTS WERE FOUND IN THE SYSTEM AND THE AIRCRAFT WAS RETURNED TO SERVICE. NO FURTHER ACTION REQUIRED. [END}

AIRCRAFT DEPARTED KADS ON 01/19/2019 AS THE AIRCRAFT WAS CLIMBING THROUGH FL200, THE CREW OBSERVED THE RT ENGINE OIL PRESSURE WAS LOW. THE CREW ELECTED TO SHUTDOWN THE RT ENGINE AS A PRECAUTION. AIRCRAFT RETURNED TO KADS(HOME)AND LANDED WITHOUT INCIDENT. UPON A VISUAL INSPECTION OF THE RT ENGINE, MAINTENANCE OBSERVED THAT THE OIL CAP WAS NOT LOCKED IN POSITION THAT OIL HAD BEEN LOST FROM THE OIL TANK. MAINTENANCE SERVICED THE ENGINE OIL TO FULL AND INSTALLED THE OIL CAP AND LOCKED IT. {END}

DURING INSPECTION, THE VERTICAL STEM OF THE LOWER REAR SPAR CAP AFT ANGLE - RH OF THE REAR SPAR ASSEMBLY WAS FOUND TO BE CORRODED AT ABOUT CWS 325 WITH .078" REMAINING THICKNESS ON THE WEB STEM FLANGE. REPAIR DEFINITION WAS RECEIVED FROM CESSNA ENGINEERING TO REPAIR CORRODED AREA BY BLENDING / ALODINE TREATMENT / PRIMER APPLICATION. REPLACEMENT OF RIVETS WERE NECESSARY UPON REASSEMBLY WITH NEW RIVETS.\ IN THE AREA

CORROSION WAS FOUND AT MULTIPLE SITES ON THE VERTICAL STABILIZER REAR SPAR CAPS. AFTER BLENDING, THE REMAINING THICKNESS AT EACH SITE WAS MEASURED USING ULTRASOUND. ALL CORROSION DAMAGE WAS REMOVED BY BLENDING AND CESSNA ENGINEERING ISSUED A REPAIR DEFINITION AND APPROVAL FOR REMAINING THICKNESS TO REMAIN IN SERVICE. FINAL METAL TREATMENT WAS CARRIED OUT USING ALODINE, PRIMER AND TOP COAT.

DURING A SCHEDULED INSPECTION, MICROBIAL GROWTH WAS FOUND IN THE CENTER TANKS. AFTER CLEANING THE TANKS, CORROSION WAS FOUND ON THE LOWER SKIN AND CONNECTING STRUCTURE.

THE BRAKE SYSTEM MANIFOLD ON THE MLG STRUT ON THE LT AND RT MLG WERE FOUND GOUGED. REPLACEMENT OF BOTH MANIFOLDS AND SUPPORT CLAMPS.

MAIN LANDING GEAR FAILED TO RETRACT.

GEAR UNLOCK LIGHT STAYS ON AFTER GEAR RETRACTION. CYCLED GEAR & LIGHT EXTINGUISHED.

SLOWING BELOW 60 KTS, BRAKES RELEASED WITH NO CHANGE IN PEDAL PRESS. RELEASED BRAKE PRESS & RE-APPLIED, ACFT BEGAN TO SLOW THEN BRAKES RELEASED AGAIN. RE-APPLIED PRESS & BRAKES GRABBED ABRUPTLY.

AT 11,000 FEET & 40 MILES FROM HOU. THERE WAS A POP SOUND WITH AN AMBER CAS MESSAGE OF ACM BLEED LEAK & A BLUE CAS MESSAGE BAGGAGE HEAT OFF. A FEW SECONDS LATER THERE WAS THE SMELL OF SMOKE IN THE COCKPIT. LOOKING BACK INTO THE CABIN I COULD SEE IT FILLING WITH BLUE/GREY SMOKE. IT HAD A RUBBER BURNING SMELL. TURNED OFF BOTH BLEED AIR SOURCES & THE EMERGENCY PRESSURIZATION ON, THIS SEEM TO GIVE SOME RELIEF TO THE SMOKE. WE WERE GIVEN EMERGENCY HANDLING, LANDED RUNWAY 12 RIGHT AT HOU. EXITED THE RUNWAY & EVACUATED THE AIRCRAFT ON THE TAXIWAY. NEVER SAW THE CAS MESSAGE FOR EMERGENCY PRESSURIZATION ON. EVIDENCE OF OVERHEATING ON THE PIPES COMING OFF THE ACM. WE RAN THE APU FIRST TO TRY TO FIND ANY FAILURES, NONE WERE FOUND. STARTED EACH ENG DEPENDENTLY TO TRY & FIND A PROBLEM, NOTHING FOUND. STARTED BOTH ENGS & RAN IT UP TO CRUISE POWER, DUPLICATING AS CLOSE AS POSSIBLE ON THE GND THE CONDITION THE AIRCRAFT WAS IN WHEN THE EVENT HAPPENED, NO FAULT FOUND.

AT 11,000 FEET & 40 MILES FROM HOU. THERE WAS A POP SOUND WITH AN AMBER CAS MESSAGE OF ACM BLEED LEAK & A BLUE CAS MESSAGE BAGGAGE HEAT OFF. A FEW SECONDS LATER THERE WAS THE SMELL OF SMOKE IN THE COCKPIT. NEVER SAW THE CAS MESSAGE FOR EMERGENCY PRESSURIZATION ON.

LEFT MLG GREEN LIGHT REMAINED ILLUMINATED AFTER TAKEOFF. ALL OTHER GEAR INDICATOR LIGHTS EXTINGUISHED INCLUDING "UNSAFE" LIGHT. TOWER CONFIRMED LT MAIN GEAR WAS DOWN, EXTENDED. INSPECTED LANDING GEAR CONTROL VALVE AND FOUND THE PNEUMATIC OVER RIDE POSITION INDICATOR SLIGHTLY OUT OF DETENT. RESET INDICATOR AND OPERATED GREAR TO VERIFY THE SYSTEM. REPLACED THE LANDING GRAER CONTROL VALVE.

LEFT ELEVATOR - INBOARD LEADING EDGE SKIN HAS EXCESSIVE CORROSION.

LEFT MAIN GEAR DOOR CRACKED AT FWD HINGE ATTACHMENT.

LEFT UPPER SPEEDBRAKE HAS CORROSION X-RAY REVEALED CORROSION AT CENTER SPAR.

BOTH ELEVATOR MASS BALLAST WEIGHTS AND COVERS HAVE RUST. CORROSION REMOVAL REQUIRED FOR INSPECTION.

CORROSION FOUND ON ANTENNA DOUBLER MOUNTED TO CHIN FAIRING.

LT ELEVATOR FWD CAP CORRODED BEYOND LIMITS.

PILOT REPORTED AUTOPILOT TRIM WHEEL WOULD NOT TRIM AIRCRAFT AS COMMANDED. PROBLEM WAS CAUSED BY THE AUTOPILOT COMPUTER. THERE WAS NO EMERGENCY ACTIONS REQUIRED.