# Britten-Norman Service Bulletin 310: Revision 4 - Rights: © Britten-Norman. Filed by the FAA in regulations.gov docket FAA-2015-7777; AD 2016-06-01 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Britten-Norman Service Bulletin 310](https://openairdocs.org/service-documents/britten-norman/sb-310.md) - Title as filed: SB 310 Revision 4 - Pages: 8 - PDF: https://openairdocs.org/files/sha256/f3/b0/f3b03342837a102b2bbe05e4f9003df1d1b1c3434e2baf74eb29ce737beb9e2b - Page: https://openairdocs.org/service-documents/britten-norman/sb-310/file/f3b03342837a ## Text This text is OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 (OCR) SERVICE Britten-Norman N BULLETIN Britten-Norman Aircraft Limited Commodore House, Mountbatten Business Centre, Millbrook Road East, Southampton, SO15 1HY United Kingdom Models Affected Service Bulletin number SB 310 All Islander BN2, BN2A, BN2B, BN2T, BN2T-4S and BN2T-4S series Issue 4 - 25/09/2015 Islander aircraft and BN2A MkIIll series Trislander aircraft. PITOT/STATIC PRESSURE HEAD - INSPECTION AND TEST This is a highly recommended safety related Service Bulletin for aircraft fitted with the DU130-24 pitot/static pressure head only. 1 COMPLIANCE STATEMENT Do the inspection procedure of this Service Bulletin at the next daily check. Do the leak test procedure in this Service Bulletin within the next 50 flying hours. 2 REASON FOR CHANGE This Service Bulletin has been revised to issue 4 to amend the recommended inspection intervals from every 500 hours to every 50 hours following a number of reported DU130-24 pitot/static pressure head failures after significantly less than 500 flight hours service. 3 INTRODUCTION On receipt of this Service Bulletin, disseminate the information to all flight crew, engineers and operators as soon as possible. Incidents have been reported to Britten-Norman Aircraft Ltd where cracks have been found in the inner shell of the DU130-24 pitot/static pressure head. This Service Bulletin tells operators how to inspect the immediate inner circumferential surface of the total pressure hole in the nose of the pitot/static pressure head. The circumferential area is the soldered joint between the pitot/static pressure head outer shell and the inner shell that contains the heater element. When the aircraft is on the ground, it is recommended that the use of the pitot/static pressure head heater be kept to a minimum. Excessive use of the heating element in still air may cause the heating element to overheat, which will reduce the life of the heater element. 25/09/2015 SB 310 Issue 4 Page 1 of 8 ### Page 2 (OCR) Service Bulletin 4 APPLICABILITY This Service Bulletin is applicable to all Islander BN2, BN2A, BN2B, BN2T, BN2T-4S and BN2A MkIll series aircraft fitted with the DU130-24 pitot/static pressure head. 5 WEIGHT and BALANCE None. 6 EFFECT ON PUBLICATIONS Reference to the inspection of the circumferential area immediately inside the total pressure hole in the nose of the pitot/static pressure head will be incorporated into the maintenance documentation by amendment action at the earliest opportunity. 7 ACTION Table 1 Support Equipment Special Tools Nomenclature Identification Qty Pitot/Static Test Set (Microleak) 371030104 1 Pitot/Static Adapter (Part of Avimo Test Set) 1373 1 Pitot/Static Adapter (Alternate Tool) NB-88-0725 1 Pitot System Tool NB-88-0677 1 7.1 Inspection 1. In the flight compartment, on the switch panel, make sure that the PITOT & STALL WARNING HEATER switch is set OFF. 2. Use a strong light source to visually inspect the circumferential area made by the hard soldered joint between the pressure head outer shell and the heater element inner shell for cracks and/or other separation (refer to Fig.1). 3. If cracks and or separation are found, replace the pressure head with a serviceable item. Notes: It there are no visible cracks, within 50 flying hours, do a Pitot and Static System Leak Test (refer to paragraphs 7.2 and 7.3 for these procedures). The pitot static adapter (NB-88-0725) can be used as an alternative to the pitot static adapter shown in Figs 2 and 3. SB 310 25/09/2015 Page 2 of 8 Issue 4 ### Page 3 (OCR) Service Bulletin W STA 199.0 Cracking FWD PC-4-04112044-0065-01295-4-01-1 Fig 1 Pitot-Static System - Inspection Area 7.2 Pitot Leak Test 7.2.1 Preparation 1. In the flight compartment, on the switch panel, make sure that the PITOT & STALL WARNING HEATER switch is OFF. 2. Refer to Fig 2. 3. Carefully install the pitot system tool (2) in the pressure head (3). 4. On the pitot system tool (2), carefully turn the knob (1) to seal the pitot system. 5. Install the pitot-static adapter (5), on the pressure head (3). Make sure that the adapter does not cover the static vents. 6. Tighten the clamp ring (6). 7. On the pitot-static test set, connect the pitot output to the pitot-static adapter (5). 25/09/2015 SB 310 Issue 4 Page 3 of 8 ### Page 4 (OCR) Service Bulletin 7.2.2 Leak Test 1. Slowly increase the pitot pressure until the airspeed indicator shows 120 knots. 2. After one minute, examine the airspeed indicator display. 3. The pressure must not decrease by more than three knots. Note: If the airspeed indicator decreases by more than three knots, find the cause of the leak. 4. On the pitot-static test set, slowly adjust the pitot pressure to ambient pressure. On the airspeed indicator, the speed shows zero knots. 5. On the pitot-static adapter (5), loosen the clamp ring (6) and remove the pitot-static adapter from the pressure head (3). 6. On the pitot system tool (2), turn the knurled knob (1) to loosen the tool. Remove the tool from the pressure head (3). SB 310 25/09/2015 Page 4 of 8 Issue 4 ### Page 5 (OCR) Service Bulletin Fig 2 Pitot-Static System - Pitot Leak Test 25/09/2015 SB 310 Issue 4 Page 5 of 8 ### Page 6 (OCR) Service Bulletin 7.3 Static Leak Test 7.2.1 Preparation 1. In the flight compartment, on the switch panel, make sure that the PITOT & STALL WARNING HEATER switch is OFF. 2. Refer to Fig 3. 3. Carefully install the pitot system adapter (1) in the pressure head (4) make sure that it is covering the static vents. 4. Push the rubber adapter (6) in position over the drain hole (5). 5. Install the attachment ring (3), on the rear of the pressure head (4). Carefully push the attachment ring forward to secure. 6. On the pitot static adapter (1) tighten the clamp ring (2). 7. On the pitot-static test set, connect the static output to the pitot-static adapter (1). 7.2.2 Leak CAUTION Do not let the vertical speed indicator show more than 1500 feet per minute when static pressure is increased or decreased. Damage to the instrument can occur. Note: If a microleak test set is used, the rate of change in static pressure is set to 1700 feet per minute. 1. In the flight compartment, on the altimeter, turn the adjusting control and set the barometric pressure scale to the airfield barometric pressure. 2. On the altimeter, make sure that the altitude shows zero ft. plus or minus 50 ft. 3. Slowly decrease the static pressure until the altimeter shows 2000 ft. 4. On the altimeter, after one minute, the altitude must not change by more than 100 ft. 5. On the pitot-static test set, slowly adjust the static pressure to ambient pressure. On the altimeter, the speed shows zero ft. plus or minus 50 ft. 6. On the pitot-static adapter (1), loosen the clamp ring (2) and remove the pitot-static adapter from the pressure head (4). 7. If necessary, do a Pitot Heater and Stall Warning Heater Operational Test. 8. Remove all tools, materials and equipment from the work area. Make sure the work area is 9. Complete all documentation relating to this procedure. SB 310 25/09/2015 Page 6 of 8 Issue 4 ### Page 7 (OCR) Service Bulletin 4-34-11-40003-4-01 Fig 3 Pitot-Static - Static Leak Test 8 MANPOWER The inspection and test procedure will take approximately 1 hour. 9 PROVISIONING The special tools required are available from Britten-Norman Ltd. Customer Services Department, at Britten-Norman Group Ltd. Bembridge Airport, Isle of Wight, PO35 5PR, United Kingdom. 10 FOLLOW ON ACTION The following are to be repeated every 50 hours: • An inspection of the pressure head for cracks and damage. • A check of the drain traps for moisture. If moisture is present purge complete system with warm air for five minutes. • A leak test of the pitot-static system. If any cracks or damage to the pressure head is found, please notify Britten-Norman Aircraft Ltd in accordance with Service Letter 58 for further instructions. 11 APPROVAL The technical content of this document is approved under the authority of DOA number EASA.21J.138. Signed. Date 25/9/15 25/09/2015 SB 310 Issue 4 Page 7 of 8 ### Page 8 (OCR) Service Bulletin Intentionally blank SB 310 25/09/2015 Page 8 of 8 Issue 4 --- 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, except the copies of manufacturers’ service documents, which belong to their rights holders.