MD Helicopters Safer. Quiter. Smoother.

Service Letters for Models 369D, 369E, 369FF, 500N & 600N

Last Updated: 14 October 2011

Size 369D
SL369D-
or DL-
369E
SL369E-
or EL-
369F/FF
SL369F-
or FL-
500N
SL500N-
or NL-
600N
SL600N-
Subject Issue/
Reissue Date
54K SL369D-124 SL369E-076 SL369F-069 SL500N-024 SL600N-021 KRA 405B Radio ALTIMETER 14 OCT 2011
93K SL369D-123 SL369E-075 SL369F-068 SL500N-023   ENGINE POWER OUT WARNING CONTROL UNIT - FILTER INSTALLATION 20 JUL 2011
46K SL369D-121 SL369E-073 SL369F-066 SL500N-021 SL600N-019 KAMATICS SHAFT AND COUPLING OVERHAUL/EXCHANGE PROGRAM ANNOUNCEMENT 22 DEC 2010
50K SL369D-122 SL369E-074 SL369F-067 SL500N-022 SL600N-020 TECHNICAL PUBLICATIONS PRICE INCREASE 22 DEC 2010
65K SL369D-120 SL369E-072 SL369F-065 SL500N-020 SL600N-018 TECHNICAL PUBLICATIONS PRICE INCREASE 28 MAY 2010
38K         SL600N-016 YEARLY FUEL TRANSFER SYSTEM FUNCTIONAL CHECK 06 MAY 2010
41K SL369D-119 SL369E-071 SL369F-064 SL500N-019 SL600N-017 HELICOPTER OPERATION IN VOLCANIC ASH ATMOSPHERE 06 MAY 2010
33K         SL600N-015 Fuselage Aft Section and Tailboom Modification
(Ref. AD 2008-20-05fr)
17 APR 2008
40K       SL500N-018 SL600N-014 NOTARŪ Fan Tension-Torsion Strap Replacement 27 DEC 2007
32K       SL500N-017 SL600N-013 Thruster Control Cables 13 FEB 2007
30K SL369D-118 SL369E-070 SL369F-063     Certain Helicopters Not Eligible for FAA Certificate of Airworthiness 31 MAR 2004
32K SL369D-117 SL369E-069 SL369F-062 SL500N-016 SL600N-012 Availability of MDHI Publications in Electronic Format 17 SEP 2003
33K       SL500N-015 SL600N-011 Fan Control Tube Vibration 22 JUL 2002
34K SL369D-116 SL369E-068 SL369F-061 SL500N-014 SL600N-010 New Standard Warranty Statment 02 MAR 2001
35K       SL500N-013    NOTARŪ Fan Diffuser Interchangeability 09 NOV 2000
33K SL369D-115R1 SL369E-067R1 SL369F-060R1 SL500N-012R1 SL600N-009R1 Availability of Federal Aviation Administration Supplemental Type Certificates for MD Helicopters 26 JUN 2000

33K

SL369D-114 SL369E-066 SL369F-059 SL500N-011 SL600N-008 Availability of Federal Aviation Administration Airworthiness Directives Affecting MD Helicopters 23 MAY 2000
55K 113 65 58 010 007 Required Inspections and Critical Inspection Areas 16 AUG 1999
32K 112 64 57 009 006 Transfet of Ownership of the Light Helicopter Line 19 FEB 1999
40K 111R1 63R1 56R1 008R1 005R1 Torque Event/Rin Explanation 15 MAY 2001
30K 109 61 54 006 004 Main Rotor Blade Compatibility 19 OCT 1998
          003 NOT ISSUED  
Tailboom Replacement
NOT ISSUED
34K         002 Collective Controls Replacement 14 APR 1998
35K 108 60 53 005 001 Service Bulletin/Letter Designations 13 FEB 1998
25K 106 58 51 003   Alternate/ Recommended Engine Oil Tank Seal 01 JUL 1997
32K 105 57 50     Compensation for Complying With Tail Rotor Blade Notice 10 MAY 1995
29K 104 55 49     Alternate Means of Compliance to AD 94-24-04 21 DEC 1994
32K       002   New MD520N Standard Warranty Statement 01 JUN 1994
47K 102 53 47     Antenna Location and Flight Maneuver Caution 22 MAR 1993
36K 101 52 46     Main Rotor Blade Inspection Program 27 JAN 1993

46K

100R3 51R3 45R2     MAINTENANCE AND OPERATION REQUIREMENTS FOR SAFE OPERATION OF SURPLUS 369A (OHEA) SERIES HELICOPTERS 10 NOV 2004
33K 98 49 43     New Configuration Main Rotor Blades/Abrasion Strips 19 DEC 1991
32K 97 48 42     Main Rotor Hub Balancing 11 OCT 1991
54K 96 47 41     Availability of Skid Mounted Light Assembly Shims. 01 MAY 1991
165K 82.2 33.2 40     Facet Scavenge Oil Filter Kit, P/N 1741050 (369H Series, 369D and 3 69E) and P/N 1741300 (369F/FF) 21 NOV 1990
37K 95 46 39     Storage Time Limitations of the Engine N2 and Rotor Tachometer Indicators (P/N 369D24518(BSC), -3, & -5) 01 SEP 1990
34K 94 45 38     Compliance to BREEZE-EASTERN Customer Service Bulletin CSB-120 (Warning Plate for Cargo Hooks). 15 DEC 1989
85K 92 43 36     Federal Investigation of Central Aviation and Marine Corporation (CAMCO). 27 OCT 1989
34K 91 42 35     Availability of Wire Strike Protection System (Trademark WSPS) on all MDHC 369 Series Helicopters 15 SEP 1989
31K 90 41 34     Availability of Main Transmission Filler Cap Extension (MDHC P/N 369D25112) 05 AUG 1989
33K 88.1 39.1 32.1     Special Warranty Consideration for the Main Rotor Hub Strap Pack Inspection 15 SEP 1989

36K

87R3 38R3 31R3     CUSTOMER REQUESTS FOR ORIGINAL AIRCRAFT RECORDS 10 NOV 2004
35K 86.1 37.1 30.1     New MDHC Authorized Helicopter Airframe Repair Facilities 15 SEP 1989
32K 84 35 28     Validity of Spectrum Oil Analysis Program (S.O.A.P.) 15 JAN 1989
32K 80 30 22     Chafe Wrapping of Stainless Steel Tube Assemblies and Allison Commercial Service Letter CSL 145, CSL 1140 and CSL 3092, dated May 1, 1988 26 MAY 1988
30K 79         Additional Inspection Requirements of the Breeze-Eastern Rescue Hoist System 18 MAY 1988
61K 76 27 18     Addition of Identification Decal on Aircraft Exterior. (Compliance to FAR 45.11[D]) 06 MAY 1988
59K 74 25 16     Illustrated Parts Breakdown of Ground Handling Wheel Assemblies (PN 369D2610) 19 FEB 1988
30K 70 21 11     Unauthorized Distribution of Main Rotor Hub Overhaul Manual 15 JUN 1987
32K 68 19 9     External Scavenge Oil Filter System 01 MAY 1987
29K 67 18 8     Re-Lubrication of Bearings in Storage 06 APR 1987
31K 64 14 6     Main Rotor Hub Overhaul Authorization 17 MAR 1986
32K 61 12 5     Explanation of MDHC Parts Serialization 15 SEP 1985
41K     4     Tri-Flow Wash Procedure - Main Rotor Hub 01 MAR 1985
32K 59 10 2     Major Installations and Alterations to Your Hughes Helicopter 12 NOV 1984
33K 58 9       Unauthorized Tail Rotor Teeter Bearings 16 MAY 1984
67K 57 5 1     Surplus or Bogus 369D21100 Series Main Rotor Blades 10 FEB 1984
    56       Not Issued  
35K   7       Installation of Surplus Military Parts Salvaged or Used Parts on Model 500D Helicopters 10 FEB 1984
36K 41.1         Installation of Surplus Military Parts Salvaged or Used Parts on Model 500D Helicopters 10 FEB 1984
35K 52         New Attitude Gyro Indicator and Support Assembly 25 FEB 1983
34K 50         Prevention of Water Leakage Through Canopy Geon Strips 10 JAN 1983
34K 49         Ground Testing - Engine Automatic Reignition and Engine Anti-Ice Fuel Filter Systems 22 NOV 1982
33K 42         Lubrication of Drive End Bearing Liner in Aircraft Parts Corp Model 150SG Series Starter-Generator 26 MAR 1982
33K 40         Field Replacement of ‘‘O" Ring for PN 369A8321 Oil Tank Filler Cap 02 NOV 1981
33K 38         New Protective Boots for Main Rotor Hub and Tail Rotor Assembly 01 SEP 1981
34K 36         Tail Rotor Drive Shaft Flexible Coupling PN 369A5501 and 369H92564 - Treatment with Molykote Metal Protector 21 AUG 1981
31K 34         Ground Handling Precautions for Main Rotor Blades with Elastomeric Dampers 31 JUL 1981
32K 31         Substitution of Wet Spline Drive Starter-Generator for Existing Dry Spline Drive Starter-Generator 13 MAR 1981
33K 27         Compliance with FAA Airworthiness Directive and Hughes Mandatory (Red Border) Service Information Notices 30 SEP 1980
37K 23.2         Interchangeability of PN 369D21100 Series Main Rotor Blades; PN 369D21100-509 Main Rotor Blade Now Standard Production Configuration 01 MAR 1984
147K 21         New Comfort Clip for Seat Belt and Shoulder Harness Assemblies, PN 369H6541, 369H6541-21, -23 and -25 10 DEC 1979
485K 19         Operation and Maintenance Guidelines for Model 250-C20B Engine Fuel System 01 AUG 1979
52K 10         INSCO Instrument Specialties Co. Inc. Sales and Service Facilities 22 MAY 1978
32K 7         Utililzation of Engine Particle Separator and Engine Compressor Water Wash Kits 14 FEB 1978
MD Explorer MD 600N MD 520N MD 530F MD 500E