Training Reference Only

.&.-r , """~!j',I.TM SB369H-245 SB369D-201

SB369E-O95 SB369F-O79SB500N-O23 SB600N-O31

SERVICE BULLETIN DATE: 15 MAY 2001PAGE 1 OF 2

II MANDATORY 11111111111111 MANDATORY 11111111111111 MANDATORY II

MAIN ROTOR BLADE ASSEMBLY TORQUE EVENT INSPECTION

1. PLANNING INFORMATION:

A. Aircraft Mfected;

All 369H/HE/HS/HM/D/E/FF, 500N, and 600N series helicopters.

B. Assembl Com onents Mfected b this Bulletin:

Main Rotor Blade Assembly (PIN 369A1100-501, -503, -505, -507, -511)Main Rotor Blade Assembly (PIN 369D21100, -501, -503, -516, -517, -523)Main Rotor Blade Assembly (PIN 369D21102, -503, -517, -523)Main Rotor Blade Assembly (PIN 369D21120-501)Main Rotor Blade Assembly (PIN 369D21121-501)Main Rotor Blade Assembly (PIN 369D21123-501)

C. Reason:Some operators have experienced cracking of main rotor blades. All of these cracked bladeshave been associated with a high number of external lifts per hour which exceed the fatiguespectrum. This bulletin references criteria to assist operators in understanding their levelof usage, the impact of that usage on the main rotor blade life and the correspondinginspections required to locate cracks that might occur. Failure to comply with this bulletinmay result in the loss of a main rotor blade.

D. Descrintion:

Procedures in this Bulletin provide owners and operators with information pertaining toperforming the main rotor blade torque event inspection and determining an inspectioninterval.

E. Time Qf Comnliance:

This Bulletin shall be accomplished at the next 100-Hour inspection, or no later than 90 .;1h..days after the issue date of this Bulletin. It

F. FAA Annroval:

The design engineering aspects of this Bulletin have been shown to comply with theapplicable Federal Aviation Regulations, and are FAA Approved.

G. Warrant~ Polic~:

N/AH. Disnosition of Parts Removed:

ScrapI. Other Publications Mfected:

Handbook of Maintenance Instructions (CSP-H-2), Revision 17, 15 May 2001 or laterAppendix B (CSP-H-4), Revision 1, 14 May 2001 or laterHandbook of Maintenance Instructions (CSP-HMI-2), Revision 29 dated 11 May 2001 orlaterRotorcraft Log Book (CSP-RLB), Revision 2 dated 17 February 2000 or later.

Copyright 1999-2001 by MD Helicopters Inc. .This docum~nt may.be reprl?dul!ec! and distributed provided no fee is charged, thetext is not modJfied, and thJS copyrJght notu:e JS mcluded.

II MANDATORY 11111111111111 MANDATORY 11111111111111 MANDATORY II

.~M.TM' .SB369H-245 SB369D-201 ~ ~'-SB369E-O95 SB369F-O79SB500N-O23 SB600N-O31

DATE: 15 MAY 2001 SERVICE B ULLETINPAGE 2 OF 2

II MANDATORY 11111111111111 MANDATORY 11111111111111 MANDATORY II

J. Points of Contact:

For further assistance, contact your local MDHI Field Service Representative (refer to thelatest revision of the "At Your Service" handbook for address and telephone numbers) orcontact the Field Service Department at MDHI, Mesa, Arizona. Telephone 1-800-388-3378or (480) 346-6387. DATAFAX: (480) 346-6813.

2. ACCOMPLISHMENT INSTRUCTIONS:

(Ref. Handbook of Maintenance Instructions (CSP-H-2) and Appendix B (CSP-H-4) orHandbook of Maintenance Instructions (CSP-HMI-2).

A. Prenaration

(1). Review the definition of a Torque Event (TE) (Ref. CSP-HMI-2 or CSP-H-4, Section04-00-00, Torque Event (TE».

(2). Review Rotorcraft Log Book entries to determine current number ofTE accumulated oneach main rotor blade. If the current number of TE cannot be reliably determined,13,720 TE shall be used.

(3). Record current number of TE accumulated on each main rotor blade in Rotorcraft LogBook. Continue to record the number of TE accumulated throughout the life of the mainrotor blades.

B. Insnection ~

(1). Determine the main rotor blade TE inspection interval, using current number of TE(Ref. CSP-HMI-2 or CSP-H-4, Section 04-00-00, Table 1. Airworthiness LimitationsComponent Mandatory Replacement Schedule).

(2). Inspect main rotor blades at the required interval (Ref. CSP-H-2, Section 07 orCSP-HMI-2, Section 62-10-00, Main Rotor Blade Torque Event Inspection).

3. COMPLIANCE RECORD

Record compliance to this Service Bulletin in the Compliance Record section of the helicopterLog Book.

Copyright 1999-2001 by MD Helicopters Inc. .This docum~nt may .be repr~du~ea: and distributed provided no fee is charged, thetext is not modtfied, and thts copyr£ght nouce I;S £ncluded.

II MANDATORY 11111111111111 MANDATORY 11111111111111 MANDATORY II

l ""...J

..~'~. . -TM SL369H-132Rl* SL369D-II1Rl*~r. SL369E-O63Rl* SL369F-O56Rl*

SL500N-OO8Rl* SL600N-OO5Rl*

SERVICE LETTER DATE: 15 MAY 2001PAGE 1 OF 2

* Supersedes Service Letters SL369H-132, SL369D-l11, SL369E-O63, SL369F-O56, ISL500N-OO8, SL600N-OO5, dated 11 January 1999.

MD HELICOPTERS MODEL 369/500N/600NTORQUE EVENT/RETIREMENT INDEX NUMBER EXPLANATION

MD Helicopters, Inc. (MDHI) is currently establishing a new approach to tracking certainIretirement lives and inspection intervals of various helicopter components. This is being

implemented to ensure safe operation of the helicopter within the widest range of helicopterusage.

Components are assigned retirement lives based on flight test, fatigue test and fieldexperience. This life is based on a flight spectrum that is representative of maneuvers a

Iparticular model helicopter is expected to see. A flight spectrum defines flight maneuvers anda percentage of time performing these maneuvers. Each maneuver produces different loads.The number of times these loads are applied has a cumulative effect on component lives.

The MDHI flight spectrum is FAA approved and represents our knowledge of helicopter usage. .This spectrum is conservative in its representation. However, helicopter usage has changedsince we first established our helicopter spectrum. Some operators have reported exceeding theestimated average amount of high stress maneuvers in our flight spectrum. This can result in

Ireduced service life or early failure of components. Because of this, MDHI reevaluated themanner of establishing limited lives which currently considers only Time In Service (TIS).

Flight and fatigue testing have determined that a "Torque Event" (TE) accelerates fatiguedamage on certain components. A Torque Event is defined as the transition to a hover fromforward flight or any external lift operation. For this definition of TE, forward flight is .considered to be flight at any airspeed in any direction after attaining transitional lift. A flightthat has a takeoff and a landing is one (1) TE. Hover taxi with no external lift will typicallyresult in no TE's. For sling operators, each load will count as two (2) TE (pick-up anddrop-off). For example, if an operator takes off and moves six (6) sling loads then lands, thiswould total twelve (12) Torque Events (thirteen (13) if the helicopter drops off the last load andthen flies to another landing area). An external lift can either be on the cargo hook, externalhoist or in external baskets. An autorotation from forward flight to a landing or a hover is one(1) TE. In order to account for a greater number of Torque Events than what was representedin our original FAA approved flight spectrum, we are asking owners and operators to recordthe number of Torque Events that their helicopters experience. The number of Torque Eventsshould be entered into the helicopter Log Book. For each flight, the pilot should maintain acount of TE's performed. At the end of each day, the number of TE's should be added to theaccumulated number of TE's in the helicopter log or equivalent record.

Copyright 1999-2001 by MD Helicopters Inc. This document may .be repr~u.cec.z and distributed provided no fee is charged, thetext is not modifred, and this capyrzght notzce zs zncluded.

SL369H-132Rl* SL369D-IIIRl* -='~. .-TMSL369E-O63Rl* SL369F-O56Rl* "'7"'-.SL500N-OO8Rl* SL600N-OO5Rl*

DATE: 15 MAY 2001 SERVICE LETTERPAGE 2 OF 2

I Components affected by TE's will no longer have retirement lives or inspection intervals basedsolely on TIS. Components that are effected by Torque Events will have an inspection intervalbased on TE or be assigned a maximum Retirement Index Number (RIN). This RINcorresponds to the maximum allowed fatigue damage resulting from Torque Events andaccumulated flight hours. The RIN is an adjustment factor times flight hours plus another

I adjustment factor times TE, or RIN = (Adjustment factor one x flight hours) + (Adjustmentfactor two x TE). For example, if factor one = 160 and adjustment factor two = 24 and flighthours equal 1,190 hours with 12,800 TE, RIN = (160 x 1,190) + (24 x 12,800) = 497,600 RIN.The RIN system accounts for flight hours and TEs and results in equal conservatism beingapplied to all operators. A new component will begin with an accumulated RIN of zero thatwill be increased as TEs and TIS occur. The operator will record the number of TEs, TIS andincrease the number of RIN's accordingly. When the maximum number of hours or themaximum number of RIN is reached (whichever occurs first), the component will be removedfrom service.

For components that have inspections intervals based on TE, the inspection interval will occurat a set TE interval.

Refer to the latest revision of CSP-HMI-2 or CSP-H-4, Section 04-00-00, Table 1Airworthiness Limitations Component Mandatory Replacement Schedule for component lifelimits, retirement index number formulas and inspection interval requirements.

For further assistance, contact your local MDHI Field Service Representative (refer to thelatest revision. of the "At Your Service" handbook f?r address and telephone numbers) or contact ~the Field ServIce Department at MDHI, Mesa, Arizona. Telephone 1-800-388-3378 or (480) "IV346-6387. DATAFAX: (480) 346-6813.

Co ri ht 1999-2001 by MD Helicopters Inc. This document may .be repr~du~e~ and distributed provided no fee is charged, thepy g text is not modified, and this copyr~ght not~ce LS ~ncluded.

\..iOCJ:'-ttlVll-~ MD Helicopters, Inc." ," MAINTENANCE MANUAL

plus another adjustment factor times Hover taxi with no external load willTorque Events. typically result in no TEs. -

When a component reaches 1,000,000 6. External Lift and Torque Event (TE)RIN's, it has reached it's maximum life Requirementsand is to be scrapped. The 369D/E/F/FF -500/600N helicopters are

multi-use helicopters. If the helicopter is used5. Torque Event (TE) primarily for external lifts or training flights

.(high TE flights), there may be a reduction inA Torque Event (TE) 1S defined as: inspection intervals of some components.

The transition to a hover from forward I-CAUT-ioN' For safe operation of the heli-flight. '::--~~~~l~~ copter, TE's must be recorded in

the Rotorcraft Log Book. Each external liftAny external lift operation. will be recorded as two (2) TE's.

NOTE: An external lift can either be on the car- (1). Determin.e the num~er of TE's andgo hook, external hoist or in external bas- external lifts the h.elic°p.ter accumu-kets. lates per hour of flight time.

.(2). Record all TE's in Rotorcraft Log BookFor external lift operators, an external and continue to record all TE's.load is recorded as two (2) TE's (pick-up and drop-off). (3). Perform required TE inspections.

Page 6

Revision 29 04-00-00 FAA APPROVED

.MD Helicopters, Inc. CSP-HMI-2..'

MAINTENANCE MANUAL

Table 1. Airworthiness Limitations Component MandatoryReplacement Schedule

Finite Life Man datoryComponent Part Number(1) Model (2) Hours Inspection

(1) HoursMain Rotor System

Blade assembly, main rotor 3690/E(5)(6) 369021100 3530 (37) 25 (11)(20)369021100-516 3530 (37) 100 (20)369021100-517 2500 (31) 25 (22)369021100-517 3530 (37) 100 (20)369021120-501 3530 (37) 100 (20)369021100-523 4000 (37) 100 (20)

369F/FF (6) 369021102 3430 (37) 25 (11) (20)369021102-503 3430 (37) 100 (20)369021102-517 2500 (31) 25 (22)369021102-517 3430 (37) 100 (20)369021121-501 3430 (37) 100 (20)

~369021102-523 4000 (37) 100 (20) !

500N (6) 369021102-503 3430 (37) 100 (20)369021102-517 2500 (31) 25 (22)369021102-517 3430 (37) 100 (20)

~369021121-501 3430 (37) 100 (20).369021102-523 4000 (31) 100 (20)

600N 369021102-517 (21) 1900 (32)(37) 100 (20) I369021102-523 3200 (33)(37) 100 (20) i

Folding pin, main rotor blade attach 3690/E/F/FF 369A 1004 2850369A1004-3 2850369A1004-5 7600

500/600N 369A1004-5 7600

Hub subassembly, main rotor 3690/E/F/FF 369021201 8900500N

Pitch housing assembly, main rotor hub 3690 369021300 9100369021300-501 9100

369E/F/FF 369021300-501 9100500N

Retention strap assembly, main rotor hub 3690 369021210 2770 100 (4)369021210-501

369E/F/FF 369021210-501 2770 100 (4)

500/600N 369021210-501 2770 100 (4)

Bolt -lead-lag hub, main rotor 3690 369A1220 6120

3690/E/F/FF 369021220 6120

500N600N 369021220 5400 (34)

Page 7

FAA APPROVED 04 -00 -00 Revision 29

~-~--

MD Helicopters, Inc. CSP-Hl\n-2

MAINTENANCE MANUAL

-(28) Log all landings: Brace life is limited to 35400 logged landings or 5900 hours flight time if landing are notlogged (assumed six landings per one hour of flight time).

(29) Log all landings: Strut life is limited to 4170 logged landings or 696 hours flight time if landing are notlogged (assumed six landings per one hour of flight time).

(30) Log aJllandings: Foot life is limited to 23780 logged landings or 3900 hours flight time if landing are notlogged (assumed six landings per one hour of flight time).

(31) The following main rotor blades have a finite life of 2,500 hours or 15,000 torque events*, whichever occurs

first;PIN 369021100-517 with SIN H664, H665, H667, H669, H671, H672, H674, H676, H679, H680, H683 thruH724, H726 thru H999 and JOOO thru J039, J041 thru J055 andPIN 369021102-517 with SIN 1976 thru 2100,2106 thru 2115.* TORQUE EVENT (TE) -A TE is recorded for every transition from forward flight to a hover (Reference

Service Bulletins SB3690-195R3, SB369E-088R3, SB369F-075R3, SB500N-015R3).

(32) RIN = (200 x Hrs.) + (52 x TE).

(33) RIN = (160 x Hrs.) + (24 x TE).

(34) RIN = (153 x Hrs.) + (3 x TE).

(35) RIN = (50 x Hrs.) + (3 x TE). .

(36) RIN = (768 x Hrs.) + (11 x TE).

(37) After accumulation of 750 flight hours and 13,720 TE, perform Main Rotor Blade Torque Event InspectionI{Ref. Sec. 62-10-00) every 35 flight hours or 200 TE's (whichever occurs first).

Page 13/(14 blank)

FAA APPROVED 04-00-00 Revision 29

--

MD Helicopters, Inc. CSP-fil\tII':2.

MAINTENAJ.~CE MANUAL

Table 1. 100-Hour or Annual Inspection (Cont.)

Registration No. Serial No.

Helicopter Hours Torque Events

Model Requirement Chap/Sect Initial

WARNING: Do not leave pitot heater ON for more than one minute during next check; severe burns topersonnel may result.

ALL PITOT HTR switch ON for a few seconds. Heated pitot tube will feel warm to 95the touch; turn switch to OFF after check.

600N Apply power to aircraft and disconnect CIT sensor (Ref. CIT (Compressor 76-00-00Inlet Temperature) Sensor Replacement); Verify ECU FAIL light illuminates.Re-connect CIT sensor.

ALL Clean battery and inspect for: 96* Connector pins for evidence of corrosion.

* Leakage (if battery is leaking (wet), remove and replace battery).

* Battery case for cracks in support flanges.

* Dc wiring for chafing caused by wiring rubbing against battery case.

* Deep cycle charge (recondition) battery every 100 hours or on

conditional basis at operator's discretion.

ALL Functionally check and inspect all installed avionics, auxiliary or optional 97systems and equipment. Do not actuate hoist guillotine or emergency floats.

ENGINE COMPARTMENT

ALL Exhaust stack(s) and exhaust supports for cracks, defects and improper 78attachment.

ALL Engine compartment plumbing and electrical relay installation on left or right 96side oleo (landing gear damper) support fitting for good condition andsecurity of mounting. Diodes for broken terminals and wires. Diode bracketfor security and corrosion.

ALL Entire engine for: 71* Loose bolts; loose or broken connections. 75

76* Accessories for security and broken or missing lockwire.

* Fuel and oil lines for chafing and kinking.

* Fuel drain line valve for leakage.

* Oil cooler and cooler deflector for security and obvious damage.

* Accessible areas for obvious damage; evidence of fuel and oil leaks.

* Engine mounts for cracks and play in mounting hardware at engine and

airframe (retorque any loose mounting bolts).* Fuel control and compressor exterior for condition and security.

369D/E/FF RPM governor lever control rod (replace if aluminum). 76-10-00

500N369D/E/FF Clean and lubricate drive splines of starter-generator drive shaft, and female 96

500N splines in engine accessory gear case on dry spline installations.

369D/E/FF Anti-ice air tubes and compressor scroll for cracks or breaks at the anti-ice 75-10-00500N air valve and bleed port. If cracks exist, check engine for possible vibration

causes (Ref. Engine Anti-icing System and applicable AJlison Engine

Operation and Maintenance Manual).

Page 9Form HOEO05 (Rev 05/01) 05-20-00 Revision 29

"", ,..~

\j~.t'-.t1.1Vll-~ MU MellcopIers, Inc..-': ~ MAINTENANCE MANUAL

Table 1. 100-Hour or Annual Inspection (Cont.) -

Registration No. Serial No.

Helicopter Hours Torque Events

Model Requirement Chap/Sect Initial

AFTER INSPECTION

ALL Touch-up all damaged paint and exterior markings, as necessary. 20

ALL Ensure all fluid levels are correct; service as required. 12

ALL Perform operational check of particle separator filter (Ref. Scavenge Air 71-10-10

Operational Check).ALL Install or close all stressed panels, covers and trim panels removed or 52-50-00

opened for inspection. Check closure, fit and security. All loose equipment for

proper stowage.

CAUTION: Helicopter must not be flown unless controls access panel and fuel cell access panels in cargocompartment are securely installed. These are stressed panels.

POST INSPECTION RUN UP

See applicable Pilot's Flight Manual for cockpit check and engine starting procedures. For troubleshootingprocedures, refer to applicable section of this manual.

100-HOUR OR ANNUAL INSPECTION CERTIFICATION

It is certified that this helicopter has been thoroughly inspected as required by FAR, found to be airworthy, andappropriate entries made in the helicopter log book. It is further certified that the helicopter conforms to FAAspecifications, that all FAA Airworthiness Directives and Manufacturer's Service Notices and MaintenanceManual data have been complied with, and the helicopter records are in proper order

SignatureRating Type or Certificate No.

Date

2. Retirement Index Numbers Attachment Refer to Section 04-00-00 for components..requiring calculation of RIN's/TE's and

Table 2 IS to be used for calculating and information pertaining to calculation ofrecording the Retirement Index Number (RIN) RIN's/TE's.or Torque Events (TE) of components that areaffected by Torque Events (TE). .

Component must be scrapped when It reachesThis record ofRINs/TE's should be kept as a 1,000,000 RIN's or maximum TE's (Ref. Sec.

permanent record. 04-00-00).

Table 2. Permanent Record of Retirement Index NumbersiTorque Events

Component Part No. Serial No. Hours TE's RIN's Signature

Pag~ ~o05 20 00 Form HOEO05 (Rev 05/01)

ReVIsIon 29 --

,, c

Group of Companies

Hughes 500 Series Repetitive Airworthiness Directives and Service Bulletins

A/C Reg.: ___________ A/C W.O. No.: ___________

A/C T.A.T.: _____________ Date: _______________

Denotes certification by approved pilots is acceptable

November 9, 2007

AD/ DN Reference Description Hours Initial

AD86-20-07 DN143.1 Part II

Check for T/R backlash or looseness by rocking the T/R back & forth in its plane of rotation. The blade should not move in excess of 0.75 inches at the blade tip without rotation of the main rotor (applicable to Bendix couplings only)

*DAILY

AD88-17-09 R1 DN-151 Part II Para. (a)

Examine T/R Transmission. Installation by checking torque stripes for movement of the trans. (Cracks in the torque paint), fretting products, gapping between faying surfaces &/or rotation of the nuts & studs. (Applicable to Hughes tailbooms only)

*25

AD 95-03-13

DN-51.8 Part II Note:

Insp. of main rotor blade root fitting assembly & m/r hub lead-lag link assembly for cracks, condition & slippage marks on bushings. (Applicable to Main Rotor blades -515 and prior dash numbers) (Applicable to links -31 and prior dash numbers)

*25 *15 hrs

AD 2005-21-02 SB 2100-3R3, SB 369D-201R2

Inspect M/R blades with a 10x magnifying glass for cracks on the first 24 inch inboard area of the bottom side of blade

35 Hrs or 200 Tq Events

AD 89-02-01 R1 Para C

DN-154 Part 1 Note:

With M/R blades removed, inspect strap pack laminates in accordance with Para (a)-(l) of DN-154, Part I, Insp. Procedures. (Applicable to all our Aircraft) Compliance change with 2 failed laminates

100 25 hrs

AD 88-17-09 R1 DN-151 Part IV Para (a)(b)

Check the torque of each T/R transmission-mounting nut to 95 +/-3 inch-pounds plus previously noted drag torque. Reapply torque stripe paint. (Applicable to Hughes tailbooms only)

100

AD 94-24-04 DN-185 Part III

Inspect torque stripe on T/R swash plate locknut for any sign of slippage.

100

AD 95-03-13 DN-51.8 Part I

Remove M/R blades, use 5X magnifying glass to inspect M/R blade root fittings & M/R hub lead-lag links for broken or cracked lugs, etc. NOTE: bushings for condition and slippage marks. (Applicable to Main Rotor blades -515 and prior dash numbers) (Applicable to links -31 and prior dash numbers)

100

AD 96-10-09 DN-188 Part II

M/R blade root end insp. Using a 10X magnifying glass, inspect for any indications of chord wise cracking emitting from the root end fitting edge on the blade doubler & skin. Insect blade for missing or cracked adhesive paint at the root end fitting to doubler.

100

SB369D-193 R1 CSP-HMI-2 64-10-00

Inspect leading edge of tail rotor blades inboard of the abrasion strips for any evidence of cracking. No cracks allowed.

100

AD 2007-12-23 SB 369D-200 or SB 369E-094

Remove the fairing inspection button plug. Clean and inspect the area in and around the rivet hole for cracks. Use a bright light and a 10x or 100

Group of Companies

Hughes 500 Series Repetitive Airworthiness Directives and Service Bulletins

A/C Reg.: ___________ A/C W.O. No.: ___________

A/C T.A.T.: _____________ Date: _______________

Denotes certification by approved pilots is acceptable

November 9, 2007

higher magnifying glass. Terminating action: Aerometals struts

AD 77-21-04 DN 9.2 Part II

Remove overrunning clutch subassembly and inspect ball bearing for excessive loss of grease, dryness or caking.

300

AD 81-26-01 R1 DN-99 Remove & Inspect M/R drive shaft splines for cracks (Applicable to 369D driveshaft only)

300

AD 90-19-02 HMI COM DN-164

Inspect overrunning clutch assembly for condition of race inner clutch, race outer clutch & the sprag assembly.

300 Hook hrs

AD 90-19-02 HMI COM DN-164

Inspect overrunning clutch assembly for condition of race inner clutch, race outer clutch & the sprag assembly.

Annual