# Service difficulty reports: N420MB, cancelled Apr 9, 2018

A list on [N420MB, cancelled Apr 9, 2018](https://openairdocs.org/deregistered/N420MB-2018-04-09.md).

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

- [SDR QMLA2014022314018](https://openairdocs.org/sdr/QMLA2014022314018.md): Door · missing · Feb 23, 2014 · N420MB · Bolkms BK117A3 · Hydraulic Compartment Doors
  > THE PILOT NOTICED THAT THE HYD INSPECTION DOOR ON THE FWD TRANSMISSION DECK CREST COWLING WAS MISSING FROM THE ACFT DURING A PREFLIGHT INSPECTION. OBTAINED & INSTALLED A SERVICEABLE INSPECTION DOOR. NO OTHER INFORMATION IS KNOWN AT THIS TIME CONCERNING THE W
- [SDR QMLA2011111611109](https://openairdocs.org/sdr/QMLA2011111611109.md): Spar · cracked · Nov 16, 2011 · N420MB · Bolkms BK117A3 · Rotorcraft Tail Boom
  > DURING INSPECTION, FOUND A CRACK IN THE TAILBOOM VERTICAL FIN MAIN SPAR. OPEN.
- [SDR QMLA2011081711087](https://openairdocs.org/sdr/QMLA2011081711087.md): Frame · cracked · Aug 17, 2011 · N420MB · Bolkms BK117A3 · Rotorcraft Tail Boom
  > THE MECHANIC FOUND A CRACK IN THE TAILBOOM AT FRAME 10L, DURING A SCHEDULED INSP.
- [SDR QMLA2011012911017](https://openairdocs.org/sdr/QMLA2011012911017.md): Chip Detector · contaminated · Jan 29, 2011 · N420MB · Bolkms BK117A3 · Engine Fuel Indicating System
  > NR 2 ENGINE CHIP LIGHT ILLUMINATED ALONG WITH THE MASTER CAUTION LIGHT. PILOT NOTED THAT THERE WERE NO N2 FLUCTUATIONS. AIR RETURNED AND ATTEMPTED A CHIP BURN WITH NEGATIVE RESULTS. PERFORMED SHUTDOWN OF THE NR 2 ENGINE. LANDED WITHOUT INCIDENT. MECHANIC
- [SDR R7MR707735204](https://openairdocs.org/sdr/R7MR707735204.md): Antenna · inoperative · Jun 6, 2002 · N420MB · Bolkms BK117A3 · Weather Radar System
  > WEATHER RADAR ANTENNA INOPERATIVE, HEADING ERROR MESSAGE. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR R7M2002F00016](https://openairdocs.org/sdr/R7M2002F00016.md): Seal · leaking · Sep 28, 2001 · N420MB · Bolkms BK117A3 · Turbine Section
  > NUMBER 2 BEARING SEAL IS LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT CORRECTED PROBLEM.
- [SDR R7M2002F00015](https://openairdocs.org/sdr/R7M2002F00015.md): Thermocouple · shorted · Sep 28, 2001 · N420MB · Bolkms BK117A3 · Engine Temperature Indicating System
  > THERMOCOUPLE HAS AN INTERNAL SHORT. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR R7MA707732458](https://openairdocs.org/sdr/R7MA707732458.md): Bellows · torn · Sep 20, 2000 · N420MB · Bolkms BK117A3 · Main Rotor Mast/Swashplate
  > BELLOWS WAS TORN AROUND CLAMP AND FOLD AREAS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 20001017SH017](https://openairdocs.org/sdr/20001017SH017.md): Cowling · worn · Jun 22, 2000 · N420MB · Bolkms BK117A3 · Engine Cowling System
  > CATCHER/CREST COWLING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM. (X)
- [SDR 20001127SH007](https://openairdocs.org/sdr/20001127SH007.md): Spring · worn · Jun 14, 2000 · N420MB · Bolkms BK117A3 · Turbine Section
  > SEAL RING EXPANDER - SPRING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM. (X)
- [SDR 20001127SH006](https://openairdocs.org/sdr/20001127SH006.md): Seal · worn · Jun 14, 2000 · N420MB · Bolkms BK117A3 · Turbine Section
  > FIRST TURBINE SHROUD, SEAL RING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM. (X)
- [SDR 20000721SH005](https://openairdocs.org/sdr/20000721SH005.md): Manifold · malfunctioned · May 18, 2000 · N420MB · Bolkms BK117A3 · Engine Fuel Distribution
  > FUEL MANIFOLD ASSEMBLY CAUSES ENGINE TO RUN HOT. (X)
- [SDR 2000ZZZX782](https://openairdocs.org/sdr/2000ZZZX782.md): Seal · leaking · Sep 30, 1999 · N420MB · Bolkms BK117A3 · Turbine Engine Combustion Section
  > SEAL LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 2000ZZZX781](https://openairdocs.org/sdr/2000ZZZX781.md): Seal · leaking · Sep 30, 1999 · N420MB · Bolkms BK117A3 · Turbine Engine Combustion Section
  > SEAL LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 99ZZZX3790](https://openairdocs.org/sdr/99ZZZX3790.md): Shaft · damaged · Mar 28, 1999 · N420MB · Bolkms BK117A3 · Turbine Engine Compressor Section
  > SECONDARY DAMAGE TO LAB SEAL FAILURE. REPALCED WITH NEW UNIT, CORRECTED PROBLEM. PART TOTAL CYCLES: 4270.
- [SDR 99ZZZX3789](https://openairdocs.org/sdr/99ZZZX3789.md): Seal Ring · worn · Mar 28, 1999 · N420MB · Bolkms BK117A3 · Turbine Section
  > SEAL RING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 99ZZZX3788](https://openairdocs.org/sdr/99ZZZX3788.md): Spring · worn · Mar 28, 1999 · N420MB · Bolkms BK117A3 · Turbine Section
  > SPRING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 99ZZZX3787](https://openairdocs.org/sdr/99ZZZX3787.md): Bearing · worn · Mar 28, 1999 · N420MB · Bolkms BK117A3 · Turbine Section
  > BEARING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 99ZZZX2330](https://openairdocs.org/sdr/99ZZZX2330.md): Shroud · damaged · Mar 28, 1999 · N420MB · Bolkms BK117A3 · Turbine Engine Compressor Section
  > SECONDARY DAMAGE TO LAB SEAL FAILURE. EXCESSIVE GROOVES RESULTING FROM GP BLADE DAMAGE. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 99ZZZX2329](https://openairdocs.org/sdr/99ZZZX2329.md): Blade · damaged · Mar 28, 1999 · N420MB · Bolkms BK117A3 · Turbine Engine Compressor Section
  > SECONDARY DAMAGE TO LAB SEAL FAILURE. EXCESSIVE DAMAGE TO KNIFE EDGES AND GP BLADES. REPLACED WITH NEW UNIT, CORRECTED PROBLEM. PART TOTAL CYCLES: 1,061.9.
- [SDR 99ZZZX2328](https://openairdocs.org/sdr/99ZZZX2328.md): Labyrinth Seal · warped · Mar 28, 1999 · N420MB · Bolkms BK117A3 · Turbine Engine Compressor Section
  > LABYRINTH SEAL HAD EXCESSIVE WARPAGE WHICH RESULTED IN COLLATERAL DAMAGE TO THE GP ROTOR AND SHROUD. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 99ZZZX1802](https://openairdocs.org/sdr/99ZZZX1802.md): Seal Assy · damaged · Mar 28, 1999 · N420MB · Bolkms BK117A3 · Turbine Engine Compressor Section
  > EXCESSIVE WARPAGE WHICH RESULTED IN COLLATERAL DAMAGE TO THE GP ROTOR AND SHROUD. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 99ZZZX1801](https://openairdocs.org/sdr/99ZZZX1801.md): Rotor Assy · damaged · Mar 28, 1999 · N420MB · Bolkms BK117A3 · Turbine Section
  > SECONDARY DAMAGE TO LAB SEAL FAILURE. EXCESSIVE DAMAGE TO KNIFE EDGES AND GP BLADES. REPLACED WITH NEW UNIT, CORRECTED PROBLEM. PART TC: 1,061.9.
- [SDR 97ZZZX4593](https://openairdocs.org/sdr/97ZZZX4593.md): Blade · cracked · Jun 15, 1997 · N420MB · Bolkms BK117A3 · Main Rotor Blades
  > FAILED BLADE INSPECTION. EXCESSIVE SKINS CRACKS AND BULGING. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 97ZZZX4592](https://openairdocs.org/sdr/97ZZZX4592.md): Blade · cracked · Jun 15, 1997 · N420MB · Bolkms BK117A3 · Main Rotor Blades
  > FAILED BLADE INSPECTION. EXCESSIVE SKINS CRACKS AND BULGING. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 97ZZZX67](https://openairdocs.org/sdr/97ZZZX67.md): Seal · leaking · Jul 23, 1996 · N420MB · Bolkms BK117A3 · Turbine Engine Accessory Drive
  > SEAL LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 97ZZZX66](https://openairdocs.org/sdr/97ZZZX66.md): Seal Ring · worn · Jul 23, 1996 · N420MB · Bolkms BK117A3 · Turbine Section
  > SEAL RING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH 2 EACH NEW UNITS, CORRECTED PROBLEM.
- [SDR 97ZZZX65](https://openairdocs.org/sdr/97ZZZX65.md): Seal · leaking · Jul 23, 1996 · N420MB · Bolkms BK117A3 · Turbine Engine Accessory Drive
  > SEAL LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 97ZZZX64](https://openairdocs.org/sdr/97ZZZX64.md): Seal · leaking · Jul 23, 1996 · N420MB · Bolkms BK117A3 · Turbine Engine Accessory Drive
  > SEAL LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 97ZZZX63](https://openairdocs.org/sdr/97ZZZX63.md): Seal · leaking · Jul 23, 1996 · N420MB · Bolkms BK117A3 · Turbine Engine Accessory Drive
  > SEALS LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH 3 EACH NEW UNITS, CORRECTED PROBLEM.
- [SDR 97ZZZX62](https://openairdocs.org/sdr/97ZZZX62.md): Seal · leaking · Jul 23, 1996 · N420MB · Bolkms BK117A3 · Turbine Section
  > SEAL LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 96ZZZX2810](https://openairdocs.org/sdr/96ZZZX2810.md): Rotor Assy · blade shift · Mar 1, 1996 · N420MB · Bolkms BK117A3 · Turbine Section
  > FAILED SB LT101-72-10-0153. EXCESSIVE IBPT BLADE SHIFT NR 25 +0.012 INCH. NR 24 +0.012 INCH. REPLACED WITH USED UNIT, CORRECTED PROBLEM. PART TOTAL CYCLES, 3,601.2.
- [SDR 96ZZZX510](https://openairdocs.org/sdr/96ZZZX510.md): Gyro · stuck · Nov 3, 1995 · N420MB · Bolkms BK117A3 · Directional Gyro and Indicating System
  > GYRO STUCK. READS 3.42 VOLTS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM.
- [SDR 96ZZZX509](https://openairdocs.org/sdr/96ZZZX509.md): Seal Ring · worn · Aug 18, 1995 · N420MB · Bolkms BK117A3 · Turbine Engine Combustion Section
  > SEAL RING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH 2 EACH NEW UNITS, CORRECTED PROBLEM. ENGINE TOTAL CYCLES, 8,721.5.
- [SDR 96ZZZX508](https://openairdocs.org/sdr/96ZZZX508.md): Bearing · worn · Aug 18, 1995 · N420MB · Bolkms BK117A3 · Turbine Engine Compressor Section
  > BEARING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM. ENGINE TOTAL CYCLES, 8,721.5.
- [SDR 96ZZZX507](https://openairdocs.org/sdr/96ZZZX507.md): Bearing · worn · Aug 18, 1995 · N420MB · Bolkms BK117A3 · Turbine Section
  > BEARING WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT, CORRECTED PROBLEM. ENGINE TOTAL CYCLES, 8,721.5.
- [SDR 95ZZZX5368](https://openairdocs.org/sdr/95ZZZX5368.md): Rotor Assy · blade shift · Jun 21, 1995 · N420MB · Bolkms BK117A3 · Turbine Section
  > FAILED SB LT101-72-10-0153. EXCESSIVE IBPT BLADE SHIFT NR 5, MINUS 0.017 INCH, NR 8, MINUS 0.011 INCH, NR 9, MINUS 0.009 INCH, NR 12, MINUS 0.010 INCH. REPLACED WITH NEW UNIT(S) CORRECTED PROBLEM. PART TOTAL CYCLES, 2920.6.
- [SDR 95ZZZX5377](https://openairdocs.org/sdr/95ZZZX5377.md): Rotor Assy · blade shift · May 18, 1995 · N420MB · Bolkms BK117A3 · Turbine Section
  > FAILED SB LT101-72-10-0153. EXCESSIVE IBPT BLADE SHIFT NR 5, PLUS 0.012 INCH, NR 26, PLUS 0.009 INCH. REPLACED WITH NEW UNIT(S) CORRECTED PROBLEM. PART TOTAL CYCLES, 5788.1.
- [SDR 95ZZZX5290](https://openairdocs.org/sdr/95ZZZX5290.md): Seal · leaking · May 18, 1995 · N420MB · Bolkms BK117A3 · Turbine Section
  > NR 3 BEARING SEAL LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT(S) CORRECTED PROBLEM.
- [SDR 95ZZZX5289](https://openairdocs.org/sdr/95ZZZX5289.md): Seal · leaking · May 18, 1995 · N420MB · Bolkms BK117A3 · Turbine Engine Compressor Section
  > NR 2 BEARING SEAL LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW UNIT(S) CORRECTED PROBLEM.
- [SDR 95ZZZX5269](https://openairdocs.org/sdr/95ZZZX5269.md): Seal Ring · worn · May 18, 1995 · N420MB · Bolkms BK117A3 · Turbine Section
  > FIRST TURBINE SHROUD SEAL RING WORN BEYOND SERVICEABLE LIMITS.
- [SDR 95ZZZX5268](https://openairdocs.org/sdr/95ZZZX5268.md): Seal · leaking · May 18, 1995 · N420MB · Bolkms BK117A3 · Turbine Engine Oil System
  > ACCESSORY DRIVE SEALS LEAKING BEYOND SERVICEABLE LIMITS. REPLACED WITH 3 EACH NEW UNIT(S) CORRECTED PROBLEM.
- [SDR 95ZZZX5267](https://openairdocs.org/sdr/95ZZZX5267.md): Bearing · rough · May 18, 1995 · N420MB · Bolkms BK117A3 · Turbine Engine Reduction Gear
  > ANNULAR BALL BEARING ROUGH. REPLACED WITH 4 EACH NEW UNIT(S) CORRECTED PROBLEM.
- [SDR 95ZZZY0999](https://openairdocs.org/sdr/95ZZZY0999.md): Bulb · pin broke · May 10, 1995 · N420MB · Bolkms BK117A3 · Exterior Lighting
  > ANODE PIN BROKE OFF DURING LAMP REPLACEMENT. XENON TUBE DID NOT BURST. REPLACED WITH NEW UNIT(S), CORRECTED PROBLEM.
- [SDR 95ZZZX5376](https://openairdocs.org/sdr/95ZZZX5376.md): Rotor Assy · blade shift · Feb 28, 1995 · N420MB · Bolkms BK117A3 · Turbine Section
  > FAILED SB LT101-72-10-0153. EXCESSIVE IBPT BLADE SHIFT NR 7, PLUS 0.011 INCH, NR 12, PLUS 0.018 INCH, NR 17, PLUS 0.010 INCH, NR 18, PLUS 0.010 INCH. REPLACED WITH NEW UNIT(S) CORRECTED PROBLEM. PART TOTAL CYCLES, 5811.3.
- [SDR 95ZZZX5266](https://openairdocs.org/sdr/95ZZZX5266.md): Seal Ring · worn · Feb 28, 1995 · N420MB · Bolkms BK117A3 · Turbine Section
  > FIRST TURBINE SEALS WORN BEYOND SERVICEABLE LIMITS. REPLACED WITH NEW 2 EACH UNITS(S) CORRECTED PROBLEM.
- [SDR 95ZZZX5501](https://openairdocs.org/sdr/95ZZZX5501.md): Gyro · defective · Jan 4, 1995 · N420MB · Bolkms BK117A3 · Directional Gyro and Indicating System
  > GYRO UNIT REMOVED BECAUSE OF YAW CSAS KICK. REPLACED WITH NEW UNIT(S) CORRECTED PROBLEM.

## 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 = 'N420MB' AND deregistration_id = 'N420MB-2018-04-09'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/deregistered/N420MB-2018-04-09/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.