# Service difficulty reports: N159AC

A list on [N159AC](https://openairdocs.org/aircraft/N159AC.md).

Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model. Newest first.

- [SDR JYDR20201013282](https://openairdocs.org/sdr/JYDR20201013282.md): Attach Bolt · broken · Oct 13, 2020 · N159AC · Skrsky S64F · Engine/Transmission Coupling
  > PILOTS SUDDENLY FELT A VIBRATION AND HEARD A HOWLING NOISE. THEY RETURNED TO THE LANDING SITE AND SHUT DOWN. AT INSPECTION, MAINTENANCE FOUND 1 OF 3 NAS628-15 BOLT BROKEN IN HALF ON THE NR 2 HIGH SPEED SHAFT ON THE FORWARD END, WHERE IT ATTACHES TO THE FREE
- [SDR JYDR20201008218](https://openairdocs.org/sdr/JYDR20201008218.md): Engine · overtemp · Oct 7, 2020 · N159AC · Skrsky S64F · Engine (Turbine/Turboprop)
  > AIRCRAFT WAS ON SHORT FINAL AT 50 FT AGL WHEN NR 1 ENGINE LOW SPEED CHIME CAME ON. PILOT NOTED DECREASING N1 RPM WITH RISING T% (ROLLBACK). PROPER ENGINE IDENTIFIED AND SHUT DOWN. RECORDING T5 INDICATOR CHECKED AND FOUND ENGINE HAD REACHED 784C FOR 4 SECOND
- [SDR JYD2006F00000](https://openairdocs.org/sdr/JYD2006F00000.md): Bearing · spalled · Dec 9, 2005 · N159AC · Skrsky CH54B · Main Rotor Mast/Swashplate
  > BEARING OUTER RACE SPALLED AND CRACKED. SPALLING AND CRACK ARE ON NR1 BEARING ROW ONLY. CRACK IS APPROXIMATELY 2.25 INCHES LONG. PROBABLE CAUSE IS UNKNOWN. THE BEARING RACE WILL BE ANALYZED TO DETERMINE THE CAUSE. THERE ARE NO RECOMMENDATIONS TO PREVENT RE
- [SDR 2005FA0000819](https://openairdocs.org/sdr/2005FA0000819.md): Gear · cracked · Apr 14, 2005 · N159AC · Skrsky S64F · Tail Rotor Gearbox
  > TGB AND SERVO ASSY REMOVED FROM ACRFT FOR MAKING METAL. GEARBOX DISASSEMBLED AND DURING VISUAL INSP OF OUTPUT GEAR, ONE TOOTH FOUND CRACKED. FRIVE SIDE OF TOOTH SHOWS THE MAJORITY OF CRACKING, STARTING FROM IB TO ALMOST MIDWAY ON TOOTH EXTENDING ACROSS TIP L
- [SDR 2005FA0000820](https://openairdocs.org/sdr/2005FA0000820.md): Turbine Blades · broken · Apr 13, 2005 · N159AC · Skrsky S64F · Turbine Section
  > COMPRESSOR ASSY WAS REMOVED FROM AC FOR FAILING VIBRATION ANALYSIS. DURING THE PRELIMINARY INSPECTION IT WAS NOTED THAT A PIECE OF 2ND STAGE TURBINE BLADE OUTER SHROUD KNIFE EDGE WAS MISSING. THE MISSING PIECE WAS APPROXIMATELY.500 INCH LONG AND FROM THE AF
- [SDR JYDRMDR04069](https://openairdocs.org/sdr/JYDRMDR04069.md): Housing · cracked · Dec 6, 2004 · N159AC · Skrsky S64F · Main Rotor Gearbox
  > MGB WAS REMOVED FOR MAIN SHAFT REPLACEMENT AND OVERHAUL. AFTER DISASSEMBLY OF GEAR BOX, THE UPPER HOUSING WAS LOCALLY BLENDED, ETCHED UNDER THE INPUTS AND INSPECTED BY FPI. THE HOUSING WAS REJECTED FOR CRACKS ON THE LT AND RT SIDE. POOR REWELD QUALITY OF CA
- [SDR 2005FA0000000](https://openairdocs.org/sdr/2005FA0000000.md): Bevel Gear · cracked · Nov 30, 2004 · N159AC · Skrsky S64F · Main Rotor Gearbox
  > DURING NDT INSPECTION, GEAR WAS MPI`D AND REJECTED FOR CRACKS. LOCATION OF CRACKS WERE IN ATTACHMENT FLANGE BOLT HOLES (18 EACH). EVERY HOLE HAS APPROXIMATELY.1250 INCH LONG CRACK STARTING ON THE GEAR TO SHAFT ATTACHMENT SIDE EXTENDING DOWN INTO THE HOLE.
- [SDR MDR04061](https://openairdocs.org/sdr/MDR04061.md): Bearing Race · cracked · Aug 19, 2004 · N159AC · Skrsky CH54B · Tail Rotor Head
  > TAIL ROTOR HEAD WAS REMOVED FROM AC DUE TO SUDDEN LEAKAGE FROM TAIL ROTOR GRIP. DISASSEMBLED TAIL ROTOR HEAD AND FOUND THE SHOULDER BOLT INNER RACE CRACKED ON THE BACK SLEEVE AND SPINDLE. CRACK TRAVELS COMPLETELY ACROSS BEARING CONTACT SURFACE AND COMPLETELY
- [SDR 2004F00284](https://openairdocs.org/sdr/2004F00284.md): Spacer · cracked · Jul 15, 2004 · N159AC · Skrsky S64F · Engine (Turbine/Turboprop)
  > COMPRESSOR ASSY WAS REMOVED FROM AN AIRCRAFT FOR A 1000 HOURS SCHEDULED HOT SECTION INSPECTION. DURING TEST RUN, THE ENGINE EXPERIENCED VIBES WHICH WERE OUT OF ACCEPTABLE LIMITS. THE ENGINE WAS DISASSEMBLED AND CHECKED FOR BALANCE AND WAS FOUND TO BE OUT OF
- [SDR 2004F00335](https://openairdocs.org/sdr/2004F00335.md): Seal · broken · Jul 14, 2004 · N159AC · Skrsky S64F · Engine (Turbine/Turboprop)
  > COMPRESSOR ASSY REMOVED FROM A/C FOR A 1000 TSO SCHED HOT SECTION INSP. DURING INSP, EVIDENCE RUBBING BETWEEN OUTER SHROUD OF 1ST STAGE N1 BLADES & 1ST STATE OUTER AIRSEAL KNIFE EDGES. 1 BLADE BROKEN OUTER SHROUD. CONTACT BETWEEN DAMAGED TO OUTER SHROUD OF B
- [SDR MDR04050](https://openairdocs.org/sdr/MDR04050.md): Support Beam · cracked · Apr 21, 2004 · N159AC · Skrsky CH54B · Fuselage Main, Structure
  > IN THE COURSE OF A POST FLIGHT INSPECTION, THE FIELD MAINTENANCE CREW DISCOVERED A CRACK IN THE RT MGB SUPPORT BEAM APPROXIMATELY STA 333. SL 199 AND RBL 20. THIS IS ON THE FORWARD TOP SIDE OF THE BEAM. OVERALL CRACK LENGTH APPROXIMATELY 3 INCHES. PROBABLE
- [SDR MDR04047](https://openairdocs.org/sdr/MDR04047.md): Spar · cracked · Mar 16, 2004 · N159AC · Skrsky CH54B · Main Rotor Blades
  > THE BLADE WAS REMOVED FROM THE AIRCRAFT DUE TO A RED BIM INDICATION. DURING A 10 DAY LEAK CHECK, LOSS OF PRESSURE WAS NOTED. FURTHER INVESTIGATION FOUND A.6250 INCH CRACK LOCATED ON TOP OF BLADE. THE CRACK IS LOCATED 142.5 INCHES FROM TIP END, 6.75 INCH FR
- [SDR MDR04045](https://openairdocs.org/sdr/MDR04045.md): Housing · cracked · Mar 10, 2004 · N159AC · Skrsky CH54B · Main Rotor Gearbox
  > DURING ROUTINE FIELD MAINTENANCE INSPECTIONS, A CRACK WAS DISCOVERED UNDER NR 2 INPUT (ARM PIT) APPROXIMATELY 6 INCHES LONG FROM APPROXIMATELY THE 5 TO 8 OCLOCK POSITION. THIS WAS VERIFIED BY FPI. PROBABLE CAUSE IS UNKNOWN.
- [SDR MDR03034](https://openairdocs.org/sdr/MDR03034.md): Gear · cracked · Nov 18, 2003 · N159AC · Skrsky S64F · Tail Rotor Gearbox
  > TAIL ROTOR GEARBOX WAS REMOVED FROM AC FOR MAKING METAL. TAIL ROTOR GEARBOX WAS DISASSEMBLED IN THE OVERHAUL SHOP AND VISUALLY FOUND A CRACKED GEAR TOOTH ON THE OUTPUT GEAR. DURING THE MPI INSPECTION, WAS CONFIRMED THE TOOTH WAS CRACKED AND NO OTHER CRACKS WE
- [SDR 20010613CW018](https://openairdocs.org/sdr/20010613CW018.md): Blade · cracked · May 21, 2001 · N159AC · Skrsky S64F · Main Rotor Blades
  > REMOVED FROM AIRCRAFT FOR BIM INDICATION. PERFORMED LEAK CHECK. DETECTED LEAK AND FOUND CRACK. CRACK IS CHORDWISE, AND.5000 INCH LONG WITH CORROSION PIT LOCATED IN CENTER. LOCATION OF CRACK IS 23.5 INCHES FROM TIP END ON BOTTOM SIDE OF BLADE AND 4 INCHES
- [SDR 98ZZZX2812](https://openairdocs.org/sdr/98ZZZX2812.md): Rollers · worn · Jul 6, 1998 · N159AC · Skrsky S64F · Alternator-Generator Drive
  > SUBMITTER STATED THIS MDR AFFECTS S-64E MODEL. ACFT WAS FLYING UNDER NORMAL CONDITIONS WHEN NR 1 AND NR 2 GEN WENT OFF-LINE AND INVERTER POWER WAS NEEDED FOR A/C TO RETURN TO LANDING. INITIAL INSP REVEALED ALL WIRES CONNECTED AND CB'S IN CORRECT POSITIONS.
- [SDR 98ZZZX2255](https://openairdocs.org/sdr/98ZZZX2255.md): Blade · fractured · Apr 24, 1998 · N159AC · Skrsky S64F · Turbine Engine Compressor Section
  > ON 4-24-98, AIRCRAFT WAS ON A FIRE FIGHTING MISSION. DURING CLIMB-OUT, A LOUD 'BANG' SOUND OCCURRED, FOLLOWED BY A LEFT YAW. THE LOAD OF WATER WAS JETTISONED AND PILOTS PUSHED MAXIMUM BEEP ON BOTH ENGINES. THE NR 1 ENG WAS CARRYING THE LOAD. THE NR 2 ENG R
- [SDR 97ZZZX4347](https://openairdocs.org/sdr/97ZZZX4347.md): Bracket Bolt · cracked · Sep 17, 1997 · N159AC · Skrsky S64F · Main Rotor Head
  > DURING OVERHAUL OF THE MAIN ROTOR HEAD, A FLUORESCENT MAGNETIC PARTICLE INSPECTION REVEALED A TOTAL OF 4 CRACK INDICATIONS IN BOLT HEAD TO SHANK RADIUS. LARGEST CRACK IS 0.200 INCH IN LENGTH RADIALLY AROUND SHANK. THREE SMALL CRACKS ARE 0.040 INCH LONG EACH.
- [SDR 97ZZZX3377](https://openairdocs.org/sdr/97ZZZX3377.md): Main Shaft · cracked · Jul 10, 1997 · N159AC · Skrsky S64F · Main Rotor Gearbox
  > PART WAS MPI'D AND FOUND TO HAVE ONE CRACK INDICATION LOCATED AT THE UPPER END OF THE LOWER SPLINES. THE INDICATION EXTENDS FROM THE SPLINE RADIUS AND GOES TOWARD THE TOOTH FACE AT APPROXIMATELY A 45 DEGREE ANGLE. LENGTH OF INDICATION IS APPROXIMATELY 0.050
- [SDR 97ZZZX3013](https://openairdocs.org/sdr/97ZZZX3013.md): Blade · cracked · Jun 13, 1997 · N159AC · Skrsky S64F · Main Rotor Blades
  > BLADE OPERATED BY ERICKSON FOR APPROXIMATELY 350.0 HOURS AND WAS REMOVED FOR A BLACK BIM INDICATION. A NITROGEN LEAK WAS DETECTED BETWEEN BLADE POCKETS NR 24 AND NR 25 ON THE LOWER SPAR SURFACE. IT APPEARED TO ORIGINATE UNDER AN APPROVED MILITARY APPLIED PAT
- [SDR 97ZZZX2477](https://openairdocs.org/sdr/97ZZZX2477.md): Main Shaft · cracked · Mar 4, 1997 · N159AC · Skrsky S64F · Main Rotor Gearbox
  > MGB MAIN SHAFT INSPECTION. TWO SPLINES FOUND CONTAINING ONE INDICATION EACH. INDICATIONS LOCATED ON THE LOAD SIDE OF THE SPLINE AND IN THE ROOT AREA. LENGTH OF INDICATIONS WERE APPROXIMATELY 0.100 INCH LONG. INDICATION DID NOT EXTEND ONTO THE TOOTH FACE OF
- [SDR 96ZZZX5313](https://openairdocs.org/sdr/96ZZZX5313.md): Tablock · missing · Jan 26, 1996 · N159AC · Skrsky S64F · Turbine Engine Compressor Section
  > TABLOCK FOUND MISSING AT HIDDEN DAMAGE INSPECTION CONDUCTED ON COMPRESSOR BEING PROCESSED INTO THE REPAIR STATION ON 1-26-96. THE LAST OVERHAUL WAS PERFORMED BY EAC ON 8-4-94. WHEN INSPECTING THE COMPRESSOR THROUGH THE INLET, CONTACT OF 3RD STAGE BLADE NOTED

## 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 = 'N159AC' AND registry_match = 'registration'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/aircraft/N159AC/reports

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