ALERT SERVICE BULLETIN December 2012 ENGINE FIRE EXTINGUISHER BOTTLE STEM INSPECTION

Transcription

1 ALERT SERVICE BULLETIN December 2012 MODEL AFFECTED: SUBJECT: 412/412EP ENGINE FIRE EXTINGUISHER BOTTLE STEM INSPECTION HELICOPTERS AFFECTED: Serial numbers through 33213, through and and through [Serial number and subsequent will have the intent of this bulletin accomplished prior to delivery.] COMPLIANCE: Part I: Stem fittings shall be inspected before May 1 st, DESCRIPTION: Part II or Part III: Discharge tube rework or replacement shall be completed before December 1 st, Part IV: Tubes modified per Part II of this bulletin are to be inspected every 600 hour / 12 month or until Part III is accomplished. Bell Helicopter has been made aware of engine fire extinguisher bottle stem fitting (P/N 13034, or ) failures due to corrosion. This has occurred on Pacific Scientific, HTL / Kin-Tech Division fire extinguisher bottles. This bulletin provides visual inspection guidance for the fire extinguisher bottle stem fittings on fire extinguisher containers P/N /-105. The corrosion is the result of wash fluid entering the fire extinguisher agent delivery tube holes, which can flow backwards to the bottle fittings. Rework of the dispersant tube to add a drain hole is provided within this bulletin. Discharge tubes must be reworked or replaced to meet the intent of this bulletin. Applicability of this bulletin to any spare part shall be determined prior to its installation on an affected helicopter. Page 1 of 12

2 APPROVAL: The engineering design aspects of this bulletin are FAA/ODA approved. CONTACT INFO: For any question regarding this bulletin, please contact: MANPOWER: Bell Helicopter Product Support Engineering Medium Helicopters Tel: / psemedium@bh.com Approximately 4 man-hours are required to complete this bulletin. This estimate is based on hands-on time, and may vary with personnel and facilities available. WARRANTY: There is no warranty credit applicable for parts or labor associated with this bulletin. MATERIAL: Required Material: The following material is required for the accomplishment of this bulletin and may be obtained through your Bell Helicopter Textron Supply Center. Part Number Nomenclature Qty AN735C16 NAS NAS1149C0316R MS *Required for Part III only **Required for Part II only Consumable Material: None required. Tube assembly Tube assembly Loop Clamp Bolt Washer Nut 1* 1* 2** 2** 2** 2** Page 2 of 12

3 SPECIAL TOOLS: None required. WEIGHT AND BALANCE: Not affected. ELECTRICAL LOAD DATA: Not affected. REFERENCES: BHT-412-IPB Illustrated Parts Breakdown BHT-412-MM Maintenance Manual Pacific Scientific, HTL / Kin-Tech Division, Bulletin SB STEM PUBLICATIONS AFFECTED: BHT-412-IPB Illustrated Parts Breakdown BHT-412-MM Maintenance Manual ACCOMPLISHMENT INSTRUCTIONS: Part I: Stem Fitting Inspection 1. Prepare helicopter for maintenance. WARNING Make sure that no power is applied to helicopter electrical systems and helicopter is properly grounded while performing maintenance on fire extinguishing system. 2. Disconnect electrical wires from fire extinguisher bottle squibs and install jumper wires (shorting device) as per BHT-412-MM. 3. Disconnect tubes 1, 2, 3 and 4 (ref. Figures 1 and 2). Page 3 of 12

4 CAUTION Do not look directly into discharge outlet during inspection process. 4. Using a safety mirror, inspect fire bottle discharge nozzle stem (ref Figure 3) for corrosion, by viewing into the discharge outlet as indicated in Pacific Scientific, HTL / Kin-Tech Division Bulletin SB STEM (ref. CAUTION Corrosion damage that has reduced any one stem leg by an estimated 50 percent must be treated with extreme caution to prevent inadvertent discharge. CAUTION Do not rotate outlet, cartridge or housing nut when corrosion is evident. 5. When corrosion is detected, refer to Pacific Scientific, HTL / Kin-Tech Division Bulletin SB STEM. 6. If corrosion damage is estimated to be 50 percent or more on any one of the stem legs it is necessary to discharge the fire bottle before returning it to an authorized service center for nozzle replacement as indicated in Pacific Scientific, HTL / Kin- Tech Division Bulletin SB STEM. 7. Fire extinguisher bottles requiring replacement due to corrosion shall be removed and installed as per BHT-412-MM. -NOTE- When accomplishing Part II or Part III of this bulletin concurrently with Part I, tube installation is not required. 8. Install tubes 1, 2, 3 and 4 as shown in Figures 1 and 2 for completion of Part I of the accomplishment instructions. Page 4 of 12

5 9. Remove extinguisher bottle squib jumper wires (shorting device) and connect electrical wires to fire extinguisher bottle as per BHT-412-MM. 10. Make an entry in the helicopter logbook and historical service records indicating compliance with Part I of this Alert Service Bulletin. Part II. Discharge Tube Modification -NOTE- When accomplishing Part III of this bulletin Part II is not required. 1. Prepare helicopter for maintenance. WARNING Make sure that no power is applied to helicopter electrical systems and helicopter is properly grounded while performing maintenance on fire extinguishing system. 2. Disconnect tubes 1, 2, 3 and 4 (ref. Figures 1 and 2). 3. Disconnect existing discharge tubes P/N and -002 and then loosen nut AN on aft tee fittings to provide sufficient space to remove discharge tube (ref. Figure 4 and 5). 4. Add a drain hole in the bottom center of each tube, within a 3 inch range of the most aft hole as indicated in Figure 5. Drill hole using No. 10 drill (0.1935in). Deburr holes as required. 5. Cover the aft upper hole in each modified tube using AN735C16 loop clamp, NAS bolt, NAS1149C0316R washer and MS nut. 6. Identify modified discharge tubes with a FM at the end of the existing part number using a vibrating stylus. The height of the lettering shall match the existing part number size. Markings shall not exceed inch in depth. 7. Position the modified discharge tubes for installation and tighten the AN nuts at each tee fitting (ref. Figure 5). Tighten discharge tube fittings. Page 5 of 12

6 8. Install tubes 1, 2, 3 and 4 and tighten fitting (ref. Figures 1 and 2). 9. Make an entry in the helicopter logbook and historical service records indicating compliance with Part II of this Alert Service Bulletin and establish a 600hr / 12 month reoccurring inspection referenced in step 9. Part III. Discharge Tube Replacement -NOTE- When accomplishing Part III of this bulletin, Part II and Part IV are not required. 1. Prepare helicopter for maintenance. WARNING Make sure that no power is applied to helicopter electrical systems and helicopter is properly grounded while performing maintenance on fire extinguishing system. 2. Disconnect tubes 1, 2, 3 and 4 (ref. Figures 1 and 2). 3. Disconnect existing discharge tubes P/N /-001FM and -002/002FM and then loosen nut AN on aft tee fittings to provide sufficient space to remove discharge tube (ref. Figure 4). 4. Install replacement tubes P/N and -102 containing drain holes. 5. Install tubes 1, 2, 3 and 4 and tighten fitting (ref. Figures 1 and 2). 6. Make an entry in the helicopter logbook and historical service records indicating compliance with Part III of this Alert Service Bulletin. Part IV. Modified Discharge Tube Inspection -NOTE- Part IV Inspection not required when Part III Discharge Tube Replacement has been accomplished. Page 6 of 12

7 1. Visually inspect the loop clamp P/N AN735C16 installed on modified discharge tubes P/N FM and -002FM every 600 hour / 12 month for condition and security or until Part III of this bulletin is accomplished. 2. Make an entry in the helicopter logbook and historical service records indicating compliance with Part IV of this bulletin. Page 7 of 12

8 1. Tube assembly Tube assembly Figure 1 - View Center Line Looking Right Page 8 of 12

9 3. Tube assembly Tube assembly Figure 2 - View Center Line Looking Left Page 9 of 12

10 Figure 3 - View Looking Into the Discharge Outlet at Stem Page 10 of 12

11 Figure 4 - Discharge Tubes R/H (shown), P/N (opposite) Page 11 of 12

12 Figure 5 - Tube Modifications Page 12 of 12

13 HTL/KIN-TECH DIVISION SERVICE BULLETIN TO: OPERATORS WHO HAVE PACIFIC SCIENTIFIC UNIT X (BELL PART NUMBER and 105) INSTALLED ON BELL 212/412 HELICOPTERS SUBJECT: POSSIBLE SUDDEN RELEASE OF OUTLET ASSEMBLY 1. INTRODUCTION Pacific Scientific has been advised by Bell Helicopter of the possibility of the referenced unit having uncontrolled sudden release of the outlet assembly due to stem corrosion. If washer water or its residue remains on the discharge nozzle stem, corrosion and possible failure could result. 2. SCOPE This Service Bulletin applies only to Pacific Scientific unit part number X installed on Bell 212/412 helicopters. 3. REFERENCE All available safety guides. 4. COMPLIANCE Mandatory 5. INSTRUCTIONS A. With unit installed on airframe: (Unit is under pressure: acknowledge and use all safety procedures and equipment.) 1. Disconnect outlet hoses from unit. 2. With strong light and safety mirror, look inside unit outlet. Do not look directly into nozzle until servicability has been established. a. If no corrosion is visible, re-attach hose and document findings. (see below for sample of unit with no corrosion) SB STEM February 10, 2012 Pacific Scientific Company d/b/a Pacific Scientific Aviation Services Northwest 102 nd Road, Suite 6, Miami FL 33178, USA Pacific Scientific Company Tel: +1 (305) Fax: +1 (305)

14 5. INSTRUCTIONS (continued) b. If any corrosion is present, send unit for service. (Due to nature of discrepancy do not directly look into outlet) (Do not rotate outlet, cartridge, or housing nut) (see below for samples of corrosion and corrosion residue) c. If 50% or more of the stem leg is intact, (see photo) unit may be shipped for service with unit charged. If 50% or less of any leg is intact request kit and discharge unit. Discharge Information B. Obtain discharge kit from Pacific Scientific Aviation Services (see CONTACT INFORMATION (Unit is under pressure, acknowledge and use all safety procedures and equipment.) (Due to nature of discrepancy do not directly look into outlet) (Do not rotate outlet, cartridge, or housing nut) C. Remove unit from helicopter, secure unit in vice using attach lugs. Install NAS supplied in kit on unit fill fitting. (see below) SB STEM February 10, INSTRUCTIONS (continued)

15 D. Attach discharge tool to unit, hand tight only, open valve (round-shaped, black knob) on tool. (see below) (If unit outlets and tool present interference do not rotate outlets, remove and replace valve from tool.) E. Attach hose to tool and receiving tank. (see below) Tank is under vacuum, see gauge on receiving bottle, do not open valve until ready for discharge. If mistake occurs attach tank to vacuum source only if tank is empty. F. Holding tool upright twist open handle on discharge tool. (tool on bottom, bottle on top) You should hear flow of contents, tool and bottle will get cold (see below) SB STEM February 10, 2012

16 5. INSTRUCTIONS (continued) G. Open gate valve slowly on receiving tank, ensure tool is up-right (tool on bottom bottle on top) (You will hear agent rush into tank, transfer will take seconds) H.. Check gauge, wait till reading stabilizes. I. Close tool valve handle and close gate valve on receiving tank. J. Remove hose from tool. Slight residual agent may release from hose. K. Tool valve handle can be opened to release remaining nitrogen gas. Once gas is released, close tool valve handle. (release of nitrogen gas will be colorless and harmless) L. When unit is totally empty retract T handle on tool to retract fill fitting plunger. M. Repeat steps C through L for other unit if required. Do not use discharge kit to discharge more than 2 units. N. Repack tools and enclose bottles. O. Send to Pacific Scientific (see CONTACT INFORMATION) SB STEM February 10, 2012

17 6. CONTACT INFORMATION Pacific Scientific Aviation Services nd Road Suite 6 Miami, Florida Ph: Please mention SB STEM Pacific Scientific Limited Howarth Road Maidenhead Berkshire SL6 1AP United Kingdom Ph: 44 (1628) Please mention SB STEM 7. COST A. Kit rental paid in advance, for 14 calendar day rental FOB Miami, Florida $500 Additional 10 calendar day extended rental after written approval $800 B. Paid in advance Kit deposit, not refunded after 15 days $15,000 Tools missing or damaged tools will not be replaced, tool cost as follows Discharge tool $12,000 Receiver bottle $ 2,000 ea Hose $ 150 Shipping Box $ 500 SB STEM February 10, 2012