# Service difficulty reports: N991AA A list on [N991AA](https://openairdocs.org/aircraft/N991AA.md). Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model. Newest first. - [SDR HYIA20201116001](https://openairdocs.org/sdr/HYIA20201116001.md): Beam · cracked · Nov 12, 2020 · N991AA · Cessna 402C · Nacelle/Pylon, Main Frame > DURING MAINTENANCE A CRACK WAS DISCOVERED ON THE INBOARD FACE OF THE RIGHT HAND INBOARD ENGINE BEAM IN THE AREA OF THE VERTICAL ATTACH CHANNELS FOR THE CROSSOVER BEAM. THIS CRACK WAS DISCOVERED AFTER CHANGING THE CROSSOVER BEAM VERTICAL ATTACH BRACKET P/N: 56 - [SDR HYIA20190410001](https://openairdocs.org/sdr/HYIA20190410001.md): Cylinder · failed · Mar 11, 2019 · N991AA · Cessna 402C · Reciprocating Engine Cylinder Section > PILOT REPORTED RIGHT ENGINE SURGING AFTER TAKEOFF. MAINTENANCE INSPECTED AND FOUND THE #3 CYLINDER TO BE AT FAULT. THE #3 CYLINDER WAS REPLACED WITH NO FURTHER DEFECTS NOTED. - [SDR HYIA20180316001](https://openairdocs.org/sdr/HYIA20180316001.md): Fitting · cracked · Mar 15, 2018 · N991AA · Cessna 402C · Nacelle/Pylon, Attach Fittings > WHILE PREPPING FOR A SID 57-10-16 INSPECTION OF THE SPAR STRAP AND NACELLE FITTINGS, A CRACK WAS FOUND ON THE OUTBOARD SIDE OF THE RIGHT OUTBOARD FITTING, JUST FORWARD OF THE SPAR STRAP. - [SDR HYIA20170828015](https://openairdocs.org/sdr/HYIA20170828015.md): Fitting · cracked · Jan 4, 2017 · N991AA · Cessna 402C · Nacelle/Pylon, Attach Fittings > DURING A ROUTINE INSPECTION, A CRACK WAS FOUND IN THE RT INBOARD NACELLE FITTING. THE CRACK WAS FOUND ON THE INBOARD SIDE OF THE FITTING, JUST FORWARD OF THE SPAR STRAP. THE CRACK MEASURED.049 IN LENGTH. - [SDR HYIA20161212001](https://openairdocs.org/sdr/HYIA20161212001.md): Motor · burned out · Dec 9, 2016 · N991AA · Cessna 402C · Heating System > THE PILOT REPORTED "BURNING ODOR WHEN CABIN HEATING SYSTEM IN USE DURING FLIGHT AND BLOWER NOT BLOWING ON GROUND." AFTER INSPECTING, MAINTENANCE FOUND THE HEATER BLOWER MOTOR BURNED OUT. THE HEATER BLOWER WAS REMOVED AND REPLACED AND OPS CHECKED GOOD. - [SDR 8PCR20161103001](https://openairdocs.org/sdr/8PCR20161103001.md): Coil · fractured · Nov 3, 2016 · N991AA · Cessna 402C · Reciprocating Engine Cylinder Section > DURING EXAMINATION OF ENGINE CORE FOR OVERHAUL, THE NR 5 CYLINDER EXHAUST VALVE ROTOCOIL WAS FOUND TO BE FRACTURED. THE TOP CIRCUMFERENCE OF THE ROTOCOIL STRUCTURE HAD FRACTURED FROM THE ROTOCOIL ASSEMBLY AND REMAINED CAPTURED BY THE EXHAUST ROCKER ARM WHERE - [SDR HYIA20160902111](https://openairdocs.org/sdr/HYIA20160902111.md): Exhaust Valve · damaged · Aug 29, 2016 · N991AA · Cessna 402C · Reciprocating Engine Cylinder Section > CYLINDER REMOVED DUE TO LOW COMPRESSION AT INSPECTION, EXHAUST VALVE DISPLAYS EVIDENCE OF HEAT DAMAGE. - [SDR HYIA20160902110](https://openairdocs.org/sdr/HYIA20160902110.md): Exhaust Valve · damaged · Aug 29, 2016 · N991AA · Cessna 402C · Reciprocating Engine Cylinder Section > CYLINDER REMOVED DUE TO LOW COMPRESSION AT INSPECTION, EXHAUST VALVE DISPLAYS EVIDENCE OF HEAT DAMAGE. - [SDR HYIA20160902109](https://openairdocs.org/sdr/HYIA20160902109.md): Exhaust Valve · damaged · Aug 29, 2016 · N991AA · Cessna 402C · Reciprocating Engine Cylinder Section > CYLINDER REMOVED DUE TO LOW COMPRESSION AT INSPECTION. EXHAUST VALVE DISPLAYS EVIDENCE OF HEAT DAMAGE. - [SDR HYIA201608010011](https://openairdocs.org/sdr/HYIA201608010011.md): Lifter · damaged · Jul 29, 2016 · N991AA · Cessna 402C · Reciprocating Engine Cylinder Section > PILOT REPORTED DURING RUN-UP, RT ENGINE RPM OSCILLATES, 100 RPM. MAINTENANCE INSPECTED AND FOUND THE NR 3 CYLINDER EXHAUST LIFTER PITTED, THE NR 3 INTAKE LIFTER COLLAPSED AND THE NR 5 CYLINDER INTAKE LIFTER COLLAPSED. MAINTENANCE R & R THE LIFTERS IAW O/H MA - [SDR HYIA20160801001](https://openairdocs.org/sdr/HYIA20160801001.md): Lifter · collapsed · Jul 29, 2016 · N991AA · Cessna 402C · Reciprocating Engine Cylinder Section > PILOT REPORTED DURING RUN-UP, RT ENGINE RPM OSCILLATES 100 RPM. MAINTENANCE INSPECTED AND FOUND THE NR 3 CYLINDER EXHAUST LIFTER PITTED, THE NR 3 INTAKE LIFTER COLLAPSED AND THE NR 5 CYLINDER INTAKE LIFTER COLLAPSED. MAINTENANCE R & R THE LIFTERS IAW O/H MAN - [SDR HYIA20160712002](https://openairdocs.org/sdr/HYIA20160712002.md): Lifter · collapsed · Jul 2, 2016 · N991AA · Cessna 402C · Reciprocating Engine Cylinder Section > PILOT REPORTED THE RIGHT ENGINE MANIFOLD PRESSURE & RPM SURGE AT TAKE-OFF POWER. MAINTENANCE INSPECTED INTAKE SYSTEM, TURBO SYSTEM, INDEXED FUEL SELECTOR & REPLACED THE RIGHT ENGINE NR 1 CYLINDER EXHAUST LIFTER IAW OH MM 72. - [SDR HYIA20160701001](https://openairdocs.org/sdr/HYIA20160701001.md): Relay · failed · Jun 24, 2016 · N991AA · Cessna 402C · Engine Starting System Wiring > PILOT REPORTED "RIGHT STARTER STAYS ENGAGED" MAINTENANCE FOUND RIGHT STARTER RELAY FAILED. REMOVED AND REPLACED RT STARTER RELAY, RAN STARTER AND ENGINE- ALL OPERATION GOOD. - [SDR HYIA20150827003](https://openairdocs.org/sdr/HYIA20150827003.md): O-Ring · damaged · Aug 26, 2015 · N991AA · Cessna 402C · Master Cylinder/Brake Valve > PILOT REPORTED LT BRAKE FAILED UPON LANDING. R & R O RING ON PISTON IN LT MASTER CYLINDER, SERVICED WITH HYD FLUID. OPERATIONAL & LEAK CHECKED GOOD. - [SDR HYIA20140414049](https://openairdocs.org/sdr/HYIA20140414049.md): Drag Brace · cracked · Aug 8, 2013 · N991AA · Cessna 402C · Landing Gear Retraction/Extension System > AT SCHEDULED INSPECTION, NLG DRAG BRACE, OEM PN 5142002-5, WAS FOUND TO BE CRACKED IN THE AREA OF NLG ACTUATOR ATTACH POINT. METHOD OF INSPECTION WAS DYE PENETRANT. THIS CRACK WAS FOUND TO BE BEYOND LIMIT ALLOWABLE. THIS UNIT HAS BEEN SCRAPPED & A REPLACEME - [SDR HYIA991AANOSE](https://openairdocs.org/sdr/HYIA991AANOSE.md): Uplock Switch · failed · Jun 23, 2011 · N991AA · Cessna 402C · Landing Gear Position and Warning > CREW REPORTED DURING CRUISE FLIGHT, GEAR UNLOCK LIGHT ILLUMINATED. GEAR WAS CYCLED ONCE WITH SAME INDICATION. GEAR WAS SELCTED DOWN, THREE GREEN DOWN AND LOCK LIGHTS ILLUMINATED BUT GEAR UNLOCK LIGHT REMAINED ILLUMINATED. AIRCRFT RETURNED TO KBOS WHERE MAIN - [SDR HYIA20140415064](https://openairdocs.org/sdr/HYIA20140415064.md): Drag Brace · cracked · Jun 20, 2011 · N991AA · Cessna 402C · Landing Gear Retraction/Extension System > AT SCHEDULED INSPECTION, NLG DRAG BRACE, PN 5142002-5, WAS FOUND TO BE CRACKED IN THE AREA OF NLG ACTUATOR ATTACH POINT. METHOD OF INSPECTION WAS DYE PENETRANT. THIS CRACK WAS FOUND TO BE WITHIN ALLOWABLE LIMIT OF MEB91-11R1. THIS UNIT HAS BEEN REPAIRED IAW - [SDR HYIA991AAWSHT211](https://openairdocs.org/sdr/HYIA991AAWSHT211.md): Heater · burned · Feb 27, 2011 · N991AA · Cessna 402C · Windshield/Door Rain/Ice Removal > CREW REPORTED, ON CLIMB OUT, STARTED SMELLING ELECTRICAL TYPE BURNING. NOTIFIED ATC, DECLARED AN EMERGENCY, AND ELECTED TO RETURN. PERFORMED CHECKLIST AND WHILE TRYING TO LOCATE THE SOURCE OF THE ODOR, NOTICED ELECTRIC HEATING GRID ON WINDSHIELD DISTORTED. LAN - [SDR HYIA991AAHTRBLR](https://openairdocs.org/sdr/HYIA991AAHTRBLR.md): Fan · odor · Feb 18, 2011 · N991AA · Cessna 402C · Heating System > CREW REPORTED, DURING CRUISE FLIGHT, WITH CABIN HEATER VENTILATING FAN ON HIGH, THE FAN CIRCUIT BREAKER TRIPPED. RESET BREAKER, HAD BURNING SMELL AND BREAKER TRIPPED AGAIN. MX INSPECTED ACFT HEATING SYS, R & R CABIN HEATER VENTILATING FAN. SYS CHECKED OK. - [SDR HYIA20140415012](https://openairdocs.org/sdr/HYIA20140415012.md): Drag Brace · cracked · Jan 27, 2011 · N991AA · Cessna 402C · Landing Gear Retraction/Extension System > AT SCHEDULED INSPECTION, NLG DRAG BRACE OEM PN 5142002-5 WAS FOUND TO BE CRACKED IN THE AREA OF NLG ACTUATOR ATTACH POINT. METHOD OF INSPECTION WAS DYE PENETRANT. THIS CRACK WAS FOUND TO BE WITHIN ALLOWABLE LIMIT. THIS UNIT HAS BEEN REPAIRED IAW PROCEDURE O - [SDR HYIA991AA](https://openairdocs.org/sdr/HYIA991AA.md): Master Switch · unserviceable · Apr 1, 2009 · N991AA · Cessna 402C · Electrical Power System > CREW REPORTED AVIONICS MASTER SWITCH INOPERATIVE. MAINTENANCE REMOVED AND REPLACED SWITCH. - [SDR HYIAN991AA](https://openairdocs.org/sdr/HYIAN991AA.md): Motor · failed · Jan 25, 2009 · N991AA · Cessna 402C · Heating System > IN CRUISE FLIGHT, NOXIOUS FUMES FILLED CABIN. CREW SUSPECTED HEATER AND TURNED OFF HEATER SWITCH. FUMES DISSIPATED. TURNED HEATER BACK ON AND FUMES RETURNED. RETURNED FOR UNEVENTFUL LANDING. MAINTENANCE INSPECTED HEATER AND FOUND COMBUSTION BLOWER INOPERA - [SDR 135991030408](https://openairdocs.org/sdr/135991030408.md): Dipstick · unknown · Feb 29, 2008 · N991AA · Cessna 402C · Reciprocating Engine Oil System > DURING CLIMB-OUT, PILOT NOTED LT ENGINE MANIFOLD PRESSURE INCREASE FOLLOWED BY INCREASE IN OIL PRESSURE. PILOT TURNED BACK AND SECURED LT ENGINE AS A PRECAUTIONARY MEASURE. WHITE SMOKE WAS NOTED COMING FROM LT ENGINE. ACFT LANDED WITHOUT INCIDENT. MAINTENA ## The whole list in SQL Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS: ```sql SELECT sdr_id, difficulty_date, n_number, aircraft_make, aircraft_model, part_name, part_condition, jasc_code, discrepancy FROM 'https://openairdocs.org/data/latest/faa_service_difficulty_report.parquet' WHERE n_number = 'N991AA' AND registry_match = 'registration' ORDER BY difficulty_date DESC ``` This list as a web page: https://openairdocs.org/aircraft/N991AA/reports --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.