Bollettino Tecnico N° 139-269

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BOLLETTINO TECNICO N° 139-269 The technical content of this document is approved under the authority of DOA nr. EASA.21J.005 DATE September 30, 2011 REV . / Compliance with this bulletin is: An appropriate entry should be made in the aircraft log book upon accomplishment. If ownership of aircraft has changed, please, forward to new owner. Page 1 of 11 SUBJECT: OPERATIONAL CHECK OF NR.1 AND NR.2 HYDRAULIC SYSTEMS REASON: to confirm correct functionality of both hydraulic systems and then to introduce a periodicity. HELICOPTERS AFFECTED: all AB139/AW139 helicopters S/N 31005 and subsequent (except the S/N’s 31007, 31094, 31293, 31301, 31303, 31313 and 31329) that have not accomplished a Flight Control Hydraulic System ground functional test procedure or a main Hydraulic System operational check within the last fifty (50) flight hours prior to the receipt of this Bollettino. COMPLIANCE: within fifty (50) flight hours or two (2) months from the receipt of this Bollettino, whichever occurs first. Note Operational Checks of the Hydraulic Systems shall be repeated periodically. Refer to the approved AMPI schedule and AMP procedures for the subsequent repetitions. MANDATORY An appropriate entry should be made in the aircraft log book upon accomplishment. I f o w n e r s h i p o f a i r c r a f t h a s c h a n g e d , p l e a s e , f o r w a r d t o n e w o w n e r. An Company Via Giovanni Agusta, 520 21017 Cascina Costa di Samarate (VA) Italy Tel.: +39 0331-229111 - Fax: +39 0331-229605/222595 B.T. 139-269 Page 2 of 11 DESCRIPTION: a recent reassessment of the hydraulic systems has indentified the need for the introduction of a periodical Operational Check. REQUIRED MANPOWER: it is estimated that in order to accomplish this Bollettino two (2) man-hours (MMH) are necessary. Man-hours are based on hands-on time and may vary with personnel and facilities available. WARRANTY: N.A. REQUIRED MATERIALS: N.A. SPECIAL TOOLS: Refer to ITEP for the special tools required to comply with the AMP DM referenced in this Bollettino. WEIGHT AND BALANCE CHANGES: N.A. REFERENCES: 9 AW139 Aircraft Fault Isolation Publication (AFIP) 9 AW139 Aircraft Maintenance Publication (AMP) 9 AW139 Illustrated Tools and Equipment Publication (ITEP) PUBLICATIONS AFFECTED: 9 AW139 Aircraft Maintenance Planning Information (AMPI) 9 AW139 Aircraft Maintenance Publication (AMP) B.T. 139-269 Page 3 of 11 COMPLIANCE INSTRUCTIONS: 1. Prepare the helicopter for a safe ground maintenance. Disconnect the battery and all the electrical power sources and/or the external power supply. NOTE Performing following steps 2 thru 4, do not decrease the pressure of the Number 1 and Number 2 main- hydraulic systems to zero at the end of the single procedures as required by the applicable DM. Do not disconnect external hydraulic power and external electrical power and do not perform the related “Requirements after job completions”. 2. Do the operational check of the Number 1 power-control module. Refer to AMP, see DM no. 39-A-29-11-01-00A-321A-A. 3. Do the operational check of the Number 2 power-control module. Refer to AMP, see DM no. 39-A-29-12-01-00A-321A-A. 4. Do the operational check of the Tail shutoff valve (4). Refer to AMP, see DM no. 39- A-29-12-04-00A-321A-A. 5. With reference to figures 2 and 3, do the operational check of the PCM2 Flight control shutoff valve as follows: 5.1 On HCP (8) select the SOV2-CLOSE position to depressurize the circuit 2. 5.2 Check that F/C CIRCUIT 2 has been shut off. Make sure that: - on the instrument panel the MASTER CAUTION (6) illuminates; - on the HCP (8) the light HYD2 PRESS illuminates; - on MFD (CAS area) (7) the caution message 2 HYD PRESS and 2 SERVO are displayed; - on MFD HYDRAULIC SYNOPTIC page the closure of SOV 2 is indicated. Verify that the MAIN ROTOR / TAIL ROTOR actuators section 2 depressurization is indicated; B.T. 139-269 Page 4 of 11 - on MFD (HYD page) the displayed CIRCUIT 2 pressure value remains stable at 207 bar (3000 psi); If, on MFD HYDRAULIC SYNOPTIC page, no caution massages are in view, SOV 2 remains open, see AFIP DM no. 39-A-29-12-00-00A-421C-A (Number 2 main hydraulic system - Fault Code 2912-03). 5.3 Reset the MASTER CAUTION. 5.4 On the HCP (8) select the SOV2-OPEN position to pressurize the circuit. 5.5 Check that F/C circuit 2 has been pressurized. Make sure that: - On the instrument panels the MASTER CAUTION goes OFF. - On the HCP the light HYD2 PRESS goes OFF. - On MFD (CAS area), the caution message 2 HYD PRESS and 2 SERVO go out of view. - On MFD HYDRAULIC SYNOPTIC page, the SOV 2 must be indicated OPEN. Verify that the MAIN ROTOR / TAIL ROTOR actuators section 2 pressurization is indicated. 5.6 If the 2 SERVO caution message stays in view, see AFIP DM no. 39-A-29-12- 00-00A-421E-A (Number 2 main hydraulic system - Fault Code 2912-05). 5.7 If the 2 HYD PRESS caution message stays in view, see AFIP DM no. 39-A- 29-32-00-00A-421A-A (Indicating - Fault Code 2932-01). 5.8 If, on MFD HYDRAULIC SYNOPTIC page, the closure of SOV 2 is indicated, replace the Number 2 power-control module (3). Refer to AMP, see DM no. 39-A-29-12-01-00A-520A-A and DM no. 39-A-29-12-01-00A-520A-A. 6. With reference to figures 1 and 3, do the operational check of the PCM1 Flight control shutoff valve as follows: 6.1 On HCP (8) raise the guard and move the three-position SOV switch to SOV1-CLOSE position to depressurize the CIRCUIT 1. 6.2 Check that F/C CIRCUIT 1 has been shut off. Make sure that: - on the instrument panel the MASTER CAUTION (6) illuminates; B.T. 139-269 Page 5 of 11 - on the HCP (8) the light HYD1 PRESS illuminates; - on MFD (CAS area) (7), the caution message 1 HYD PRESS and 1 SERVO appear. - on the MFD HYDRAULIC SYNOPTIC page, the closure of the SOV 1 valve is indicated. Verify that the MAIN ROTOR / TAIL ROTOR actuators section 1 depressurization is indicated.