# Viking Air Service Bulletin V2/002: Revision A - Rights: © Viking Air. Filed by the FAA in regulations.gov docket FAA-2019-0045; AD 2020-16-15 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Viking Air Service Bulletin V2/002](https://openairdocs.org/service-documents/viking/v2-002.md) - Title as filed: SB V2-002 REV A - Pages: 5 - PDF: https://openairdocs.org/files/sha256/bb/16/bb16628c710db37505e3024de84e1968cf58576437c9d031ae7152083f169767 - Page: https://openairdocs.org/service-documents/viking/v2-002/file/bb16628c710d ## Text Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 Page 1 of 1 ATA Ref. 3200 12 September 2011 Service Bulletin V2/002 REVISION TRANSMITTAL SHEET PART REPLACEMENT - FRONT WIRE PULL FITTING VALTBS1245-1/-2 & VALTBS1244-1 REAR FLOAT STRUT & WIRE PULL FITTINGS Service Bulletin No.: V2/002 Date of Original Issue: 25 February 2011 Revision No: A Date of Issue: 12 September 2011 1. NO RETROACTIVE ACTION IS REQUIRED ON AIRCRAFT MODIFIED TO THE PREVIOUS ISSUE OF THIS SERVICE BULLETIN. 2. This revision supersedes the previous Issue of this Service Bulletin. 3. Black bars in the left margin of this Service Bulletin and the details on this Revision transmittal Sheet refer to changes made since the previous issue. This page transmits Revision ‘A’ of Service Bulletin V2/002, pages 1 thru 4, dated 12 September 2011. Service Bulletin re-issue in its entirety to revise the issue date. Remove Service Bulletin V2/002 Revision ‘NC’ dated 25 February 2011 and replace with attached. Previous issues of Service Bulletin V2/002: Initial Issue – Pages 1 thru 4 dated 25 February 2011 This Service Bulletin calls for the replacement of the front and rear wire pull fittings in the float gear. There have been reports of early failures due to stress corrosion cracking where the wire pull fittings fail prematurely. Fittings have been re-designed with a different material. The replacement fittings will be augmented by a new 100 hour inspection requirement that will look specifically for signs of stress corrosion cracking in the wire pull fittings. NOTES:! ### Page 2 1959 deHavilland Way. Sidney, B.C. Canada V8L 5V5 Tel: (250) 656 - 7227 DHC-2T Beaver 12 September 2011 S.B. V2/002 Revision ‘A’ Page 1 of 4 SERVICE BULLETIN ATA SYSTEM: 3200 NUMBER: V2/002 I. PLANNING INFORMATION A. Effectivity Aircraft Affected: All DHC-2 MK.III aircraft incorporating 6000lb Gross Weight increase STC SA91-18 or SA945NE with wire pull fittings VALTBS1244-1 and/or VALTBS1245- 1/-2. B. Reason The purpose of this service bulletin is to notify operators that a replacement front wire pull fitting is required to address a recent part failure. 1. A service difficulty investigation has revealed that: a) The front wire pull fitting VALTBS1245-1/-2 is prone to stress corrosion cracking and therefore a replacement fitting VALTBS1245-3/-4 is required. b) Clarifying the tensioning procedure of the float strut bracing wires is required for aircraft incorporating STC SA91-18 or SA945NE. c) An inspection of the wire pull fittings must be performed at every 100 hrs. 2. In addition, it was found that the aft fitting (VALTBS1244-1) is also prone to stress corrosion cracking and requires replacement with VALTBS1244-3 (LH) and -4 (RH) fittings. C. Description 1. Some in-service installations employ Viking Front Wire-Pull Fitting VALTBS1245- 1/-2. This fitting has failed due to stress corrosion cracking at low cycles/hours. a) Where VALTBS1245-1/-2 fittings exist, they must be replaced with VALTBS1245-3/-4 fittings within 90 days of the issuance of this Service Bulletin. The replacement fittings are geometrically identical to the legacy fittings but are made from a superior aluminum alloy. SUBJECT: PART REPLACEMENT - FRONT WIRE PULL FITTING VALTBS1245-1/-2 & VALTBS1244-1 REAR FLOAT STRUT & WIRE PULL FITTINGS ### Page 3 SERVICE BULLETIN V2/002 12 September 2011 S.B. V2/002 Revision ‘A’ Page 2 of 4 b) The original DHC-2 tensioning instructions for the Strut Bracing Wires are appropriate for STC SA91-18/SA945NE. See Part II, Sec 1. Step 8. c) A visual inspection of the wire pull fittings at every 100 hours is required. 2. Some in-service installations employ Viking Aft Wire-Pull Fittings VALTBS1244- 1. This fitting has been shown to be prone to failure. a) For all cases where VALTBS1244-1 fittings are installed, they must be replaced with VALTBS1244-3/-4 fittings within 180 days of the issuance of this Service Bulletin. The replacement fittings are now differentiated for installation (-3 [LH] and -4 [RH]) and are of improved geometry and aluminum alloy. b) A visual inspection of the wire pull fittings at every 100 hours is required. D. Compliance Viking Air requires operators to: 1. Replace the front fitting within 90 days of the original issue date of this Service Bulletin. 2. Replace the rear fitting within 180 days of the original issue date of this Service Bulletin. 3. Incorporate the 100 hour visual inspection requirement to the operator’s Maintenance Schedule. E. Approval The technical content of this Service Bulletin has been approved under the authority of the Transport Canada Civil Aviation (TCCA) Design Approval Organization (DAO) 04-V-02. F. Manpower Approximately 4-6 man-hours will be required to replace the front float strut wire pull fitting and another 4-6 man-hours will be required to replace the rear float strut wire pull fitting. These estimates are for direct labour performed by an experienced crew and does not include set-up, planning or other such activities. G. W eight and Balance Not applicable H. Electrical Load Data Not applicable I. Publications Affected Not applicable ### Page 4 SERVICE BULLETIN V2/002 12 September 2011 S.B. V2/002 Revision ‘A’ Page 3 of 4 II. ACCOMPLISHMENT INSTRUCTIONS A. VALTBS1245-1/-2 Front Float Strut W ire Pull Fitting Replacem ent NOTE: Retain and inspect all hardware. Inspect all mating parts for signs of corrosion or cracking. Replace any damaged hardware and/or parts as required. 1. Trestle/support the aircraft for removal of the front float strut-fuselage attachments in accordance with PSM 1-2-2. 2. Loosen the front float strut bracing wires and jam nuts. 3. Remove the cotter pin from the upper bracing wire attachment clevis pin. 4. Remove front float strut attachment locking nut and washers. 5. Drive float strut attachment bolt out using a soft punch, taking care not to damage exposed threads. 6. Remove strut bracing wire clevis pin and front wire pull fitting from aircraft. 7. Install replacement front wire pull fitting – in a manner opposite to removal. 8. Tension front strut bracing wires as follows: Insert the streamline bracing wires into the fork ends with the 4” long circular section uppermost and crank wires to obtain correct alignment and tension. Wire tension is correct when a 15 lb load applied perpendicular to the centre of the wire produces a deflection at this point of between 0.11” – 0.125”. Wires are correctly installed when there is an equal amount of thread visible between the wire and the base of the fork end – approximately 0.8”. 9. Cracked VALTBS1245-1/-2 fittings shall be reported to Viking (see Sec. III). Uncracked fittings shall be disposed of by cutting them in half. 10. Inspect the front strut wire pull fitting every 100 hours for signs of corrosion and/or cracking. See Part IV – Maintenance Instructions. B. VALTBS1244-1 Rear Float Strut W ire Pull Fitting Replacement NOTE: Retain and inspect all hardware. Inspect all mating parts for signs of corrosion or cracking. Replace any damaged hardware and/or parts as required. 1. Trestle/support the aircraft for removal of the rear float strut-fuselage attachments in accordance with PSM 1-2-2. 2. Loosen the rear float strut bracing wires and jam nuts. 3. Remove the cotter pin from the upper bracing wire attachment clevis pin. 4. Remove rear float strut attachment locking nut and washers. 5. Drive float strut attachment bolt out using a soft punch, taking care not to damage exposed threads. 6. Remove strut bracing wire clevis pin and rear wire pull fitting from aircraft. 7. Install replacement rear wire pull fitting – in a manner opposite to removal. ### Page 5 SERVICE BULLETIN V2/002 12 September 2011 S.B. V2/002 Revision ‘A’ Page 4 of 4 8. Tension rear strut bracing wires as follows: Insert the streamline bracing wires into the fork ends with the 4” long circular section uppermost and crank wires to obtain correct alignment and tension. Wire tension is correct when a 15 lb load applied perpendicular to the centre of the wire produces a deflection at this point of between 0.11” – 0.125”. Wires are correctly installed when there is an equal amount of thread visible between the wire and the base of the fork end – approximately 0.8”. 9. Cracked VALTBS1244-1 fittings shall be reported to Viking (see Sec. III). Uncracked fittings shall be disposed of by cutting them in half. 10. Inspect the rear strut wire pull fitting every 100 hours for signs of corrosion and or cracking. See Part IV – Maintenance Instructions. III. MATERIAL INFORMATION The following parts can be obtained by contacting Viking Air Product Support: PART NUMBER DESCRIPTION VALTBS1244-3/-4 Rear Wire Pull Fitting VALTBS1245-3/-4 Front Wire Pull Fitting For more information please contact: Viking Air Limited Technical Support 1959 de Havilland Way Sidney, British Columbia Canada, V8L 5V5 Email: technical.support@ vikingair.com FAX: 250-656-0673 Telephone Numbers: Regional: 250-656-7227 North America: 1-866-49-ATLAS International: 1-800-6727-6727 A. Tooling 1. Standard Aircraft Mechanics Tools IV. MAINTENANCE INSTRUCTIONS Incorporate a visual inspection of the VALTBS1244-3/-4 rear wire pull fittings and VALTBS1245- 3/-4 front wire pull fittings for corrosion and/or cracking into the recommended 100 hour inspection. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. 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