# Boeing-Vertol 234 - Type: Aircraft model (FAA registry) - Registry code: 1385051 - Manufacturer (registry): BOEING-VERTOL - Model: 234 - Aircraft type: Rotorcraft - Category: Rotorcraft - Engines: 2 · Turbo-shaft - Seats: 44 - Weight class: 20,000 lb and over - Certification: Type certificated - Data sheet: [TCDS H9EA](https://openairdocs.org/tcds/H9EA) (OpenAirDocs) - Holder: Columbia Helicopters Inc. - Registered aircraft: 6 - Page: https://openairdocs.org/model/boeing-vertol-234 Model codes come from the FAA registry's reference file. ADs are matched to them by model name and maker. ## ADs that may apply (OpenAirDocs) Matched to this model by model name and maker. Each AD's applicability may narrow it by serial number, part number or equipment. - [AD 2025-07-01](https://openairdocs.org/ad/2025-07-01): Air Data Computer · Synthetic Vision Electronic Flight Information System (Arrow STC SR09595RC or ST01523WI). Effective May 15, 2025 - [AD 2024-20-05](https://openairdocs.org/ad/2024-20-05): Flight control systems · Columbia Helicopters 234 and CH-47D. Effective Oct 28, 2024 - [AD 2023-11-07](https://openairdocs.org/ad/2023-11-07): Ground Proximity System · Airbus Helicopters 47, 206, 210 and 237 more. Effective Jun 22, 2023 - [AD 2021-23-06](https://openairdocs.org/ad/2021-23-06): Rotor flight controls · Columbia Helicopters 234 and CH-47D. Effective Jan 4, 2022 - [AD 2018-16-11](https://openairdocs.org/ad/2018-16-11): Main Rotor Head · Billings Flying Service CH-47D, 234, CH-47D and 1 more. Effective Sep 17, 2018 - [AD 2014-13-04](https://openairdocs.org/ad/2014-13-04): Nacelle/Pylon Structure and Main Rotor Blades · Columbia Helicopters 234. Effective Jul 15, 2014 - [AD 2004-06-51](https://openairdocs.org/ad/2004-06-51): Upper shaft extension · Columbia Helicopters 234. Effective Jun 18, 2004 - [AD 2002-15-02](https://openairdocs.org/ad/2002-15-02): Compressor Wheels · British Aerospace Regional Jetstream Series 3101, 234, Mystere-Falcon 20 - C5 and 22 more. Effective Aug 28, 2002 - [AD 95-22-09](https://openairdocs.org/ad/95-22-09): Spiral Bevel Ring Gear Bolted Connection · Columbia Helicopters 234. Effective Dec 6, 1995 - [AD 91-03-01](https://openairdocs.org/ad/91-03-01): Rotor Blade Rod Ends · Columbia Helicopters 234. Effective Feb 14, 1991 - [AD 87-25-05](https://openairdocs.org/ad/87-25-05): Landing Gear Spindle · Columbia Helicopters 234. Effective Dec 15, 1987 - [AD 86-23-51](https://openairdocs.org/ad/86-23-51): Transmissions · Columbia Helicopters 234. Effective Jul 20, 1987 - [AD 84-10-51 R1](https://openairdocs.org/ad/84-10-51-R1): Forward Rotor Drive Shaft · Columbia Helicopters 234. Effective Jul 24, 1986 - [AD 85-23-51 R1](https://openairdocs.org/ad/85-23-51-R1): Main Rotor Head Vertical Hinge Pins Inspection · Columbia Helicopters 234. Effective Mar 31, 1986 - [AD 84-15-03](https://openairdocs.org/ad/84-15-03): Cylinders -Flight Control System · Columbia Helicopters 234. Effective Aug 3, 1984 - [AD 83-18-51 R2](https://openairdocs.org/ad/83-18-51-R2): Pitch Shafts · Columbia Helicopters 234. Effective May 31, 1984 - [AD 84-03-51](https://openairdocs.org/ad/84-03-51): Forward Main Rotor Tie Bars · Columbia Helicopters 234. Effective Mar 14, 1984 - [AD 83-16-51](https://openairdocs.org/ad/83-16-51): Main Rotor Blade Tip Cap · Columbia Helicopters 234. Effective Oct 26, 1983 - [AD 82-20-52](https://openairdocs.org/ad/82-20-52): Transmission · Columbia Helicopters 234. Effective Apr 4, 1983 - [AD 82-20-06 R1](https://openairdocs.org/ad/82-20-06-R1): Main Rotor Hubs Inspection · Columbia Helicopters 234. Effective Oct 15, 1982 - [AD T83-25-51 R1](https://openairdocs.org/ad/T83-25-51-R1): Rotor Head Horizontal Hinge Pins · Columbia Helicopters 234 Historical (superseded or no longer in force): - [AD 2021-23-13](https://openairdocs.org/ad/2021-23-13) (historical): Ground Proximity System · Airbus Helicopters K-225, K-190A, K-240 and 237 more. Effective Dec 9, 2021 ## Information bulletins (advisory) (1) - [SAIB SW-11-03](https://openairdocs.org/saib/SW-11-03): Pitch Housings Vertical Pin Lugs. Issued Oct 22, 2010 ## Registered aircraft (6) - [N237CH](https://openairdocs.org/aircraft/N237CH): [Bank Of Utah Trustee](https://openairdocs.org/faa-owner/BANK%20OF%20UTAH%20TRUSTEE), [Salt Lake City, UT](https://openairdocs.org/faa-place/UT/Salt%20Lake%20City), built 1982, S/N MJ003 - [N238CH](https://openairdocs.org/aircraft/N238CH): [Bank Of Utah Trustee](https://openairdocs.org/faa-owner/BANK%20OF%20UTAH%20TRUSTEE), [Salt Lake City, UT](https://openairdocs.org/faa-place/UT/Salt%20Lake%20City), built 1981, S/N MJ005 - [N239CH](https://openairdocs.org/aircraft/N239CH): [Columbia Helicopters Inc](https://openairdocs.org/faa-owner/COLUMBIA%20HELICOPTERS%20INC), [Aurora, OR](https://openairdocs.org/faa-place/OR/Aurora), built 1981, S/N MJ006 - [N242CH](https://openairdocs.org/aircraft/N242CH): [Columbia Helicopters Inc](https://openairdocs.org/faa-owner/COLUMBIA%20HELICOPTERS%20INC), [Aurora, OR](https://openairdocs.org/faa-place/OR/Aurora), built 1983, S/N MJ023 - [N245CH](https://openairdocs.org/aircraft/N245CH): [Columbia Helicopters Inc](https://openairdocs.org/faa-owner/COLUMBIA%20HELICOPTERS%20INC), [Aurora, OR](https://openairdocs.org/faa-place/OR/Aurora), built 1983, S/N MJ022 - [N249CH](https://openairdocs.org/aircraft/N249CH): [Columbia Helicopters Inc](https://openairdocs.org/faa-owner/COLUMBIA%20HELICOPTERS%20INC), [Aurora, OR](https://openairdocs.org/faa-place/OR/Aurora), S/N MM821 ## NTSB investigations (2) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB ERA13RA106](https://openairdocs.org/ntsb/ERA13RA106), Jan 7, 2013: Boeing-Vertol 234 (N241CH), Pucallpa, Peru, Peru, destroyed, 7 fatal - [NTSB LAX08CA282](https://openairdocs.org/ntsb/LAX08CA282), Aug 22, 2008: Boeing BV234 (N239CH), Burns, OR, substantial damage. Probable cause: The pilot's failure to maintain clearance from obstacles while taxiing. ## FAA accident and incident reports (2) From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [Accident 20130107007199A](https://openairdocs.org/incident/20130107007199A), Jan 7, 2013: Boeing-Vertol 234 (N241CH), Pucallpa Peru, Destroyed, 7 fatal. On January 7, 2013, at approximately 1457 peruvian local time (1957 gmt), N241CH, a Boeing model 234 Vertol helicopter, operated by columbia helicopters, Peru… - [Accident 20080822842749A](https://openairdocs.org/incident/20080822842749A), Aug 22, 2008: Boeing 234 (N239CH), Burns, OR, Substantial damage. (-23) Pilot was ferrying the aircraft from portland to Utah to perform removal of equipment from high lakes in Utah. The pilot stopped for fuel in Burns, OR… ## Service difficulty reports (117, newest 50) As reported by operators and repair stations, by the model named in the report. - [SDR CHIA202511059838](https://openairdocs.org/sdr/CHIA202511059838), Nov 5, 2025: ENGINE. OVERTEMP. DURING DESCENT TO DROP OFF PASSENGERS AND CARGO, THE NR 2 ENGINE PTT BEGAN TO RISE TO 905C AND THE N1 WAS AT 102% FOR AT LEAST 15 SECONDS. ACFT RETURNED TO BASE - [SDR CHIA202508149805](https://openairdocs.org/sdr/CHIA202508149805), Aug 14, 2025: TRANSMISSION. OVERHEATED. THE NR 2 ENGINE TRANSMISSION TEMPERATURE EXCEEDED UPPER TEMPERATURE LIMIT IN FLIGHT RESULTING IN PILOTS INITIATING ENGINE XMSN HOT EMERGENCY PROCEDURES AND RETU - [SDR CHIA202508149804](https://openairdocs.org/sdr/CHIA202508149804), Aug 14, 2025: SWITCH. FAILED. NR 1 ENGINE BEEP SWITCH ON THE LT COLLECTIVE BECAME INTERMITTENTLY UNRESPONSIVE IN FLIGHT, RESULTING IN PILOTS INITIATING ENGINE BEEP FAILURE/FREEZE EMERGENCY P - [SDR CHIA202407187623](https://openairdocs.org/sdr/CHIA202407187623), Jul 18, 2024: CONTROL BOX. ACTIVATION ERROR. THREE MINS AFTER TAKEOFF, THE COPILOT NOTED A SPLIT IN TORQUE SHOWING THE #1 ENGINE HAD ROLLED BACK TO 40% TORQUE. THE ENGINE WAS BEEPED UP AND THE AIRCRAFT WAS - [SDR CHIA202407167614](https://openairdocs.org/sdr/CHIA202407167614), Jul 16, 2024: CONTROL BOX. ACTIVATION ERROR. SHORTLY AFTER INITIAL TAKE OFF FROM OUA, PILOT NOTED THE #1 ENGINE SOUNDING LIKE IT WAS ROLLING BACK. LOOKING AT THE GAUGES HE FOUND A 35% TORQUE SPLIT BETWEEN - [SDR CHIA202308076438](https://openairdocs.org/sdr/CHIA202308076438), Aug 7, 2023: BLOWER. SHORTED. DURING FLIGHT PIC/SIC NOTICED SLIGHT BURNING SMELL IN COCKPIT IN FWD FLIGHT AFTER DEPARTING DIP SITE. PIC IMMEDIATELY TURNED OFF THE HEAT VENT MASTER SWITCH, AF - [SDR CHIA2023F00247](https://openairdocs.org/sdr/CHIA2023F00247), Aug 7, 2023: BLOWER. SHORTED. DURING FLIGHT PIC/SIC NOTICED SLIGHT BURNING SMELL IN COCKPIT IN FWD FLIGHT AFTER DEPARTING DIP SITE. PIC IMMEDIATELY TURNED OFF THE HEAT VENT MASTER SWITCH, AF - [SDR CHIA5149](https://openairdocs.org/sdr/CHIA5149), Jul 19, 2022: TRANSMISSION. OVERTEMP. WE JUST COMPLETED ABOUT 2 HOURS ON A FIRE FIGHTING MISSION 15NM WEST OF BECIN FOREST SERVICE BASE AND WERE RETURNING TO BECIN BASE FOR FUEL. ABOUT HALF WAY BACK - [SDR 2021FA0000223](https://openairdocs.org/sdr/2021FA0000223), Aug 6, 2021: SHAFT. BROKEN. FORWARD LCT FAILURE- THREADED PORTION OF THE 4TH STAGE GEARSHAFT IS FRACTURED/SEPARATED THEN FOUND STUCK INSIDE TUBE COUPLING NUT - [SDR CHIA202102014798](https://openairdocs.org/sdr/CHIA202102014798), Feb 1, 2021: SUPPORT FITTING. CRACKED. DURING RAMP CHECK, FOUND VERT SHAFT #2 SIDE FORWARD ATTACHMENT SUPPORT FITTING CRACKED ALL THE WAY ACROSS THE UPPER HI-LOKS. - [SDR CHIA202010024717](https://openairdocs.org/sdr/CHIA202010024717), Oct 2, 2020: PUMP. OVERTEMP. AFTER DEPARTING BAGRAM AIRFIELD HYD OVERTEMP LIGHT ON CAUTION ADVISORY PANEL ILLUMINATED ALONG WITH CORRESPONDING SYSTEM 1 HOT LIGHT ILLUMINATING ON THE OVERHEA - [SDR CHIR20209174693](https://openairdocs.org/sdr/CHIR20209174693), Sep 17, 2020: TIE BAR. CRACKED. DURING DISASSEMBLY OF 234 FWD ROTOR HEAD ASSEMBLY P/N: 414R2001-18, S/N: A4-1425 ON SWO-060358-20, DISCOVERED GREEN TIE BAR ASSEMBLY HAS CRACK IN UPPER PLATE IN - [SDR CHIA202009064669](https://openairdocs.org/sdr/CHIA202009064669), Sep 6, 2020: CONTROL BOX. FAILED. INTERIM SUPPLEMENTAL INFORMATION: THE OVERSPEED CONTROL BOX LISTED BELOW HAS BEEN RETURNED TO THE OEM (HONEYWELL) AND IS PRESENTLY UNDER EVALUATION BY THE OEM A - [SDR CHIA2020091064669](https://openairdocs.org/sdr/CHIA2020091064669), Sep 6, 2020: CONTROL BOX. FAILED. PILOT ACCOUNT: DURING FIRE FIGHTING MISSION, NR 2 ENGINE ROLLED BACK TO INTERMEDIATE SETTING (LESS THAT FLIGHT RPM WITH RRPM DECAY, ABOVE GROUND IDLE). THIS OCC - [SDR CHIA2020090624671](https://openairdocs.org/sdr/CHIA2020090624671), Sep 2, 2020: CONTROL BOX. FAILED. NR 2 ENGINE ROLLBACK ON APPROACH TO WATER SOURCE. ENGINE SECURED PER EMERGENCY ABNORMAL CHECKLIST. COULD NOT FIND ANY DEPENDENCY DURING T/S. REMOVED AND REPLACE - [SDR CHIA2019112624266](https://openairdocs.org/sdr/CHIA2019112624266), Nov 22, 2019: ENGINE. POWER LOSS. WHILE IN CRUISE FLIGHT FROM BAGRAM THE PIC HEARD A CHANGE IN RRPM AND OBSERVED THE #1 ENGINE TQ DECREASE BY APPROXIMATELY 20% THEN RETURN TO NORMAL. HE ALERTED - [SDR CHIA202009174694](https://openairdocs.org/sdr/CHIA202009174694), Sep 17, 2019: ENGINE. POWER LOSS. ON APPROACH TO DIP SITE NR 2 ENGINE FAILED TO RESPOND. NR 2 HUNG BACK AT AROUND 20% TQ, PILOTS WENT INTO EMERGENCY ENGINE TRIM & MANUALLY BEEPED ENGINE WITH NO - [SDR CHIA201909124159](https://openairdocs.org/sdr/CHIA201909124159), Sep 12, 2019: ANGLE. CRACKED. ISOLATED CRACK FOUND IN ANGLE AT STA 160, BL 11R TO 23R, WL +56 APPROX. - [SDR CHIR20197304049](https://openairdocs.org/sdr/CHIR20197304049), Jun 12, 2019: RING. CRACKED. SWASHPLATE ASSEMBLY REMOVED FOR SCHEDULED MAINTENANCE AND RETURNED TO RS FOR OVERHAUL ON SWO-047589-19. ROTATING RING FAILED SB 234-62-1048 INSPECTION REQUIREME - [SDR CHIA2019061413966](https://openairdocs.org/sdr/CHIA2019061413966), Jun 11, 2019: DOOR FRAME. CRACKED. DURING REMOVAL OF THE AFT EMERGENCY EXIT HATCH, FOUND CRACK AT STA 482, BL 50L, WL +50. REMOVED DAMAGED WEB, LOCATED AND INSTALLED NEW WEB P/N 145S3106-5 (PO# A - [SDR CHIR20195273948](https://openairdocs.org/sdr/CHIR20195273948), May 27, 2019: HOUSING. CRACKED. THE MAINTENANCE CREW REMOVED THE AFT TRANSMISSION DUE TO AN OIL LEAK AND DISCOVERED A CRACKED FWD R/H MOUNT LUG. COMPONENT RECEIVED AT THIS REPAIR STATION 6/7/2 - [SDR CHIA201905273948](https://openairdocs.org/sdr/CHIA201905273948), May 27, 2019: TRANSMISSION. CRACKED. DURING RAMP CHECK, NOTICED OIL LEAK ON TOP OF AFT XMSN. SUSPECTED AFT VERTICAL SHAFT OIL SEAL. UPON REMOVAL AND FURTHER INSPECTION OF THE AFT XMSN, FOUND FWD RT - [SDR CHIA201905213938](https://openairdocs.org/sdr/CHIA201905213938), May 21, 2019: PRESSURE GAUGE. FAULTY. IN CRUISE FLIGHT UTILITY HYDRAULIC PRESSURE STARTED TO DECREASE BELOW OPERATING LIMITS. FOLLOWED THE EMERGENCY CHECKLIST AND LANDED AT THE NEAREST FOB WITH NO F - [SDR CHIA201904283889](https://openairdocs.org/sdr/CHIA201904283889), May 21, 2019: PRESSURE GAUGE. FAULTY. IN CRUISE FLIGHT UTILITY HYDRAULIC PRESSURE STARTED TO DECREASE BELOW OPERATING LIMITS. FOLLOWED THE EMERGENCY CHECKLIST AND LANDED AT THE NEAREST FOB WITH NO F - [SDR CHIA2019043033850](https://openairdocs.org/sdr/CHIA2019043033850), Mar 31, 2019: SKIN. DAMAGED. IN CRUISE FLIGHT AT 2500' AGL THE AIRCRAFT RECEIVED ONE ROUND ON THE BOTTOM OF AIRCRAFT AT STATION 320 RIGHT SIDE OF THE HOOKWELL. DAMAGE WAS DISCOVERED ON POST - [SDR CHIA201903213828](https://openairdocs.org/sdr/CHIA201903213828), Mar 20, 2019: SKIN. CRACKED. DURING RAMP CHECK IS WAS NOTED VISUALLY THAT THERE WAS A 6+" SKIN CRACK STA 520 BL20L WL+97. VP-000265-19 HAS BEEN CREATED TO DO THE REPAIR. - [SDR CHIA2019022523787](https://openairdocs.org/sdr/CHIA2019022523787), Feb 22, 2019: STRUCTURE. CRACKED. FOUND CRACK IN AFT TRANSMISSION AREA DURING "A" CHECK, STA. 575, WL +36, BL 35R. REMOVED EXISTING 2 DOUBLERS, CUT OUT CRACKED AREA AND FABRICATED FILLER. FABRIC - [SDR CHIA201901073719](https://openairdocs.org/sdr/CHIA201901073719), Jan 7, 2019: WEB. CRACKED. DURING C CHECK INSPECTION, FOUND A CRACK APPROX 2.6 INCHES LONG AT STA 482 WEB CENTERED AT WL 27.25 BL 47R. ADDITIONAL FURTHER EVAUATION DETERMINED REPAIR TO BE - [SDR CHIA2018111953656](https://openairdocs.org/sdr/CHIA2018111953656), Nov 15, 2018: DECK PLATE. CRACKED. DURING RAMP CHECK IT WAS NOTED THAT THE L/H SIDE CANTED DECK WL +119 LH CAP REPAIR STA 533 WAS CRACKED. REPAIRED. - [SDR CHIA201809223520](https://openairdocs.org/sdr/CHIA201809223520), Sep 22, 2018: GENERATOR. OVERHEATED. WHILE REPOSITIONING FROM ROMEO RAMP TO THE SLING LOAD AREA THE NR 1 GEN HOT LIGHT ILLUMINATED. FOLLOWED THE EP CHECKLIST GUIDANCE AND TURNED OFF THE NR 1 GEN. I - [SDR CHIA201809243519](https://openairdocs.org/sdr/CHIA201809243519), Sep 21, 2018: HOUSING. CRACKED. WHILE UNDERGOING SCHEDULED MAINTENANCE, UT INSPECTION OF FORWARD PITCH HOUSING ASSEMBLY DISCLOSED A REJECT-ABLE INDICATION OF THE UPPER VERTICAL BEARING LINER B - [SDR CHIA2018081063437](https://openairdocs.org/sdr/CHIA2018081063437), Aug 6, 2018: TRANSMISSION. MAKING METAL. CHIP LIGHT ILLUMINATED ON THE CAUTION PANEL DURING APPROACH TO LAND. CONFIRMED AFT TRANSMISSION ON THE MAINTENANCE PANEL. INSPECTED THE CHIP DETECTOR, FOUND LAR - [SDR CHIA2018081063436](https://openairdocs.org/sdr/CHIA2018081063436), Aug 6, 2018: FLT CONTROLS. FROZEN. DURING APPROACH FOR LANDING, THE THRUST LEVER FROZE, EVEN WHEN MAG BRAKE WAS RELEASED. PILOT WAS ABLE TO LAND ACFT SAFELY . RETURNED TO BASE AND SHUTDOWN FOR IN - [SDR CHIR201806303378](https://openairdocs.org/sdr/CHIR201806303378), Jun 30, 2018: TRANSMISSION. MAKING METAL. ON DEPARTURE THE XMSN CHIP LIGHT ILLUMINATED. THE AIRCRAFT RETURNED TO THE LANDING FOR FURTHER INSPECTION, WITH NO FURTHER ISSUES. THE AFT TRANSMISSION CHIP DET - [SDR CHIR201803303212](https://openairdocs.org/sdr/CHIR201803303212), Mar 12, 2018: BEAM. CRACKED. AFT ROTOR HEAD WAS IN SHOP FOR A SCHEDULED CENTER ROTOR HUB REPLACEMENT. DURING DISASSEMBLY, HORIZONTAL PIN LOCKING BEAM FOUND TO BE CRACKED. RESEARCH REVEALS T - [SDR CHIA201803103191](https://openairdocs.org/sdr/CHIA201803103191), Mar 10, 2018: PLATE. CRACKED. CRACKED FINGER PLATE. - [SDR CHIR0201802140001](https://openairdocs.org/sdr/CHIR0201802140001), Feb 11, 2018: POWERPACK. SHORTED. INFLIGHT, THE PILOT RECEIVED NO RESPONSE FROM THE PUMPS OR GATE VALVE ON THE SEI POWERPACK SYSTEM. THE 25 AMP CIRCUIT BREAKER WAS UNABLE TO BE RESET. PILOTS NOT - [SDR CHIR2017120300000](https://openairdocs.org/sdr/CHIR2017120300000), Dec 3, 2017: HOUSING. CRACKED. SUPPLEMENTAL INFORMATION TO CHIR20171203 AND WILL REQUIRE FURTHER PROCESSING BY THE SDR/SIT QUALITY CONTROL GROUP REFERENCING A TELECON ON 3/12/2019. DISASSEMBL - [SDR CHIR20171203](https://openairdocs.org/sdr/CHIR20171203), Dec 3, 2017: CONNECTOR. BROKEN. PILOTS GOT CAUTION OF XMSN LOW OIL PRESSURE ON APPROACH TO BAGRAM AIRFIELD. THEY COMPLIED WITH EMERGENCY PROCEDURE CHECKLIST, USED THE OIL PRESSURE SELECTOR SWI - [SDR CHIR201708282942](https://openairdocs.org/sdr/CHIR201708282942), Aug 22, 2017: SKIN PANEL. CRACKED. WHILE PERFORMING RAMP CHECK AT THE END OF THE DAY, MECHANIC FOUND 2 CRACKS AT BOTTOM RADIUS OF AIR STAIR ENTRANCE SKIN PANEL STA 124 WL -32 AND STA 122 WL -30. - [SDR CHIR201701122702](https://openairdocs.org/sdr/CHIR201701122702), Jan 3, 2017: WEB. CRACKED. INSPECTION REVEALED A CRACKED FORMER, PN 114S4104-13, AT STA 534, WL +72, BL 5 RIGHT. THIS AREA INCORPORATED A PREVIOUS REPAIR ONCE REMOVED, WEB WAS CRACKED AS - [SDR CHIR123020162689](https://openairdocs.org/sdr/CHIR123020162689), Dec 30, 2016: STUD. BROKEN. WHEN PAN WAS REMOVED TO PERFORM A SPIRAL BEVEL INSPECTION, MECHANIC FOUND THE NR 9 STUD BROKEN OFF AND LAYING IN THE AUX OIL SUMP PRIOR TO BEGINNING TORQUE CHEC - [SDR CHIR201611232643](https://openairdocs.org/sdr/CHIR201611232643), Nov 22, 2016: RETAINER. CRACKED. DURING THE FLUORESCENT PENETRANT INSPECTION OF THE AFT SWASHPLATE ASSY, THE UPPER RETAINER WAS FOUND TO HAVE FOUR CRACKS. - [SDR CHIR102620162623](https://openairdocs.org/sdr/CHIR102620162623), Oct 25, 2016: SUN GEAR. SPALLED. SUPPLEMENTARY INFORMATION; CHI ENGINEERING HAS INSPECTED THIS ARTICLE AND CONTACTED THE OIL MANUFACTURER (EASTMAN OIL) TO EVALUATE THE LUBRICATION PROPERTIES. N - [SDR CHIR201610262623](https://openairdocs.org/sdr/CHIR201610262623), Oct 25, 2016: SUN GEAR. DAMAGED. AFTER REMOVAL, DISASSEMBLY, AND CLEANING OF FIRST STAGE SUNGEAR OUT OF THE AFT TRANSMISSION THAT WAS REMOVED FOR HIGH SOAPS, VISUAL INSPECTION REVEALED A SIZABL - [SDR CHIR092120162577](https://openairdocs.org/sdr/CHIR092120162577), Sep 21, 2016: RETAINER. CRACKED. DURING FLUORESCENT PENETRANT INSPECTION OF SWASHPLATE ASSY, UPPER RETAINER FOUND TO HAVE 5 CRACKS. MECHANICAL TESTING, METALLURGICAL & CHEMICAL ANALYSIS PERFORM - [SDR CHIR201608262510](https://openairdocs.org/sdr/CHIR201608262510), Aug 24, 2016: BOLT. BROKEN. WHILE PERFORMING AD 95-22-09, PARA A, 250 HR SPIRAL BEVEL INSPECTION OF THE AFT TRANSMISSION NR 12 BOLT BROKE DURING INITIAL TORQUE CHECK AT 275" LB. - [SDR CHIR201608092520](https://openairdocs.org/sdr/CHIR201608092520), Aug 1, 2016: ROTOR HEAD. NOT SEATED. ROTOR HEAD WAS REMOVED DUE TO A FWD GREEN BLADE LEADING EDGE HORIZONTAL PIN SEAL PROTRUDING. DURING DISASSEMBLY ON SWO-021196-16, THE MECHANIC FOUND THAT THE SE - [SDR CHIR050220162375](https://openairdocs.org/sdr/CHIR050220162375), May 2, 2016: COMPRESSOR. DEBONDED. THE ENGINES OEM WAS ABLE TO CONFIRM THE PLASMA REPAIR OF THE COMPRESSOR CASE WAS DONE TO APPROVED DATA. NO DETERMINATION OF THE CAUSE FOR THE FAILURE HAS BEEN M - [SDR CHIR020165022375](https://openairdocs.org/sdr/CHIR020165022375), May 2, 2016: CASE. DEBONDED. (P2-CH) NR 2 ENGINE CHIP LIGHT, CONFIRMED METAL CONTAMINATION ON CHIP PLUG AND OIL FILTER. AFTER RECEIPT AT REPAIR STATION, DIFFUSER AND GP AREA INSPECTED PRIOR All 117: https://openairdocs.org/model/boeing-vertol-234/reports.md ## STCs that may be installed (OpenAirDocs) (20) Approved for this model: the STC's model list names it on its data sheet, or a series that includes it. In force first, then newest. The registry doesn't record which STCs an aircraft has. - [STC SH3319NM](https://openairdocs.org/stc/SH3319NM): Installation of Precise Flight Pulselite Control Unit in the Landing /Taxi Recognition Visual Control Light system,. Precise Flight Inc - [STC SR00925DE](https://openairdocs.org/stc/SR00925DE): Installation of Garmin GTX 335/335R and GTX345/345R transponders to provide ADS-B Out and In functionality. Peregrine - [STC SR02670SE](https://openairdocs.org/stc/SR02670SE): Installation of Simplex Model 347 Fire Fighting Tank System (FFTS); Serial Number MJ022. Columbia Helicopters Inc - [STC SH5762NM](https://openairdocs.org/stc/SH5762NM): Installation of Advanced Technology Aircraft Company engine barrier filter in accordance with Advanced Technology Aircraft Company Master Drawing List No. 234, Revision C, dated August 17, 1992, or later FAA approved revisions. This STC is issued for use in the restricted category only, and the rotorcraft must be operated accordingly with the ATAC engine barrier filter installed. Waukena Flying Services Inc - [STC SH5685NM](https://openairdocs.org/stc/SH5685NM): Installation of an improved N2 Control System in accordance with Columbia Helicopters, Inc. (CHI) Master Drawing List 93-AVI-0304, Revision H, dated August 12, 2011, or later FAA-approved revision. Columbia Helicopters Inc - [STC SR01041SE](https://openairdocs.org/stc/SR01041SE): Modification and installation of the Columbia Helicopters, Inc. C34E2057 Utility Interior Configuration, 1-19 Passengers, in accordance with Columbia Helicopters, Inc. (CHI) Master Drawing List No. 01-RDE-0602, Revision A, dated January 14, 2002, or later FAA approved revision. The modified interior will be maintained in accordance with Columbia Helicopter's FAA approved Model 234 manual, Continuous Airworthiness Maintenance Program. Columbia Helicopters Inc - [STC SH2928NM](https://openairdocs.org/stc/SH2928NM): Installation of an improved engine electrical wiring harness on Boeing Vertol 234 with Lycoming AL5512 engines. Columbia Helicopters Inc - [STC SR01674SE](https://openairdocs.org/stc/SR01674SE): Fabrication of Columbia Helicopters, Inc. (CHI) Support Assembly, part number C34D6001-9. Columbia Helicopters Inc - [STC SR01392SE](https://openairdocs.org/stc/SR01392SE): Fabrication and Installation of "Provisional Hardpoints" per Columbia Helicopter Master Drawing List, Document No. 04-RDE-0208, revision B, dated March 17, 2004, or later FAA approved revision and maintained in accordance with Instructions for Continued Airworthiness WAI0204-04, Revision 0, dated May 6, 2003, or later FAA approved revision. Columbia Helicopters Inc - [STC SR00811NY](https://openairdocs.org/stc/SR00811NY): Installation of Technisonic Industries Limited TFM-138 series transceiver models. Technisonic Industries Limited - [STC SR01834NY](https://openairdocs.org/stc/SR01834NY): Installation of Globalstar Satellite Telephone System. Atlantic Avionics Inc - [STC SH2720SO](https://openairdocs.org/stc/SH2720SO): Installation of Aero Aire Model 234 Environmental Control System (ECS) in accordance with Aero Aire Master Drawing List Document No. A234R002, Revision B, dated March 7, 1990, or later FAA Approved Revision. Enviro Systems Inc - [STC SR00955SE](https://openairdocs.org/stc/SR00955SE): Replacement of the pilot and co-pilot cockpit doors with bubble doors in accordance with McClenahan Engineering Master Drawing List No. DM0116-3, dated June 2, 2001, or later FAA approved revision. (S/N's MJ017 and MJ022). Columbia Helicopters Inc - [STC SR00956SE](https://openairdocs.org/stc/SR00956SE): Installation of offset cyclic and collective control sticks in accordance with McClenahan Engineering Master Drawing List No. DM0118-3, Revision A, dated July 13, 2001, or later FAA approved revision. For serial numbers MJ017 and MJ022 only. Columbia Helicopters Inc - [STC SR00875SE](https://openairdocs.org/stc/SR00875SE): Installation of Honeywell Solid State Flight Data Recorder (SSFDR) and Teledyne Digital Flight Data Acquisition Unit (DFDAU) per Columbia Helicopters, Inc., Master Drawing List 99-AVI-0221, Revision B, dated February 14, 2001, or later FAA approved revision. Columbia Helicopters Inc - [STC SR00841SE](https://openairdocs.org/stc/SR00841SE): Replacement of Boeing forward (P/N's 114D1245-7 or -8) and aft (P/N's 114D1350-1, -2, or -3) main rotor masts with Columbia Helicopter main rotor mast P/N's C34D5003-1 and C34D6002-9, respectively. Columbia Helicopters Inc - [STC SR00516SE](https://openairdocs.org/stc/SR00516SE): Receiving inspection and modification of amilitary surplused CH-47 transmission housing P/N 114D6241-1 for replacement of the commercial Boeing transmission housing assemby P/N 234D6241-1. Columbia Helicopters Inc - [STC SR00288SE](https://openairdocs.org/stc/SR00288SE): Modification of internal auxiliary fuel tank from a dry-cell type to a wet-cell type. Columbia Helicopters Inc - [STC SH5973NM](https://openairdocs.org/stc/SH5973NM): Approve increased altitude and weight capability when operated in Category And B operations. Columbia Helicopters Inc - [STC SH2930NM](https://openairdocs.org/stc/SH2930NM): Installation of an electronic weighting system. Measurement Systems Intl --- 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.