P.68 VARIANTS. SERVICE BULLETIN No. 250

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1 Vulcanair S.p.A. via G. Pascoli, Casoria (NA) Italy Tel Fax info@vulcanair.com P.68 VARIANTS Approved by the Vulcanair Design Organisation The technical content of this document is approved under the authority of DOA No. EASA.21J.009. Operator obligations with regards to inspections, modifications and/or other technical directives and their times of compliance are laid out in the relative Airworthiness Directives. SERVICE BULLETIN No. 250 Design Organisation Approval No. AS-SB/17/014 dated 17 November 2017 INFORMATION SUBJECT: RELOCATION OF MAGNETOMETER GMU GENERAL 1.1 AIRCRAFT AFFECTED P.68R, P.68C, P.68C-TC, P.68TC Observer and P.68 Observer 2 aircraft from s/n 469 up to s/n 503, plus s/n 458, 463, 465 and 466, and except s/n PURPOSE The purpose of this Service Bulletin is to supply information for the relocation of Magnetometer GMU 44 p/n DESCRIPTION The Magnetometer GMU 44 is slightly moved forward to avoid possible calibration difficulties, and to fix an intermittent losing of magnetic heading input data to AHRS. No additional maintenance tasks are required when the aircraft embodies this Service Bulletin; the current Scheduled Maintenance Program of the aircraft remains unchanged. 1.4 COMPLIANCE At owner s discretion. First Issue dated 07 November 2017 Page 1 of 8

2 1.5 MANHOURS The time necessary for the application of this Service Bulletin is estimated as being 4 manhours, which includes the time required to access the parts and to return the aircraft to an airworthy condition. 1.6 SPECIAL TOOLS No special tool is required. 1.7 VARIATION IN WEIGHT & BALANCE Negligible. 1.8 ELECTRICAL SYSTEM LOAD Not applicable. 1.9 REFERENCE DOCUMENTS Aircraft Parts Catalogue Aircraft Maintenance Manual G900X/G950 Installation and Maintenance Manual p/n , latest revision 1.10 PUBLICATION AFFECTED Aircraft Maintenance Manual Aircraft Equipment List 1.11 MODIFICATION TO BE CARRIED OUT BY Vulcanair Part 145 or other Approved Maintenance Organisation. First Issue dated 07 November 2017 Page 2 of 8

3 2. WORK PROCEDURE Part A Aircraft preparation. WARNING This work procedure calls for the use of substances and/or procedures that may be injurious to health if adequate precautions are not taken. This document refers only to technical suitability and in no way absolves the Operator from statutory and other legal obligation relating to health and safety at any stage of manufacture or use. WARNING Carry out this work procedure in a FOD control area. Practice Clean as you go. Monitor all your personal items. Personal items should be accounted for upon exit of FOD area. Keep and account for all your Tools, Hardware, Equipment. Dispose of trash properly. No food or beverage allowed. Before finishing this work procedure check that all the area affected by this repair is FOD free. 1. Place the aircraft in a suitable working area for the operations to be carried out. 2. Remove the baggage bulkhead and disconnect the battery cables (negative cable first). 3. Remove GMU 44 Magnetometer in accordance with concerning procedure within Aircraft Maintenance Manual. Part B Relocation of Magnetometer GMU 44 and instrument calibration. 1. If not already done, remove the GMU 44 unit from the concerning support, unscrewing the three attaching items p/n MS (see Figure 1). 2. Tag and store the removed items in a reserved area for their subsequent reinstallation. 3. Remove the magnetometer support from the fuselage dorsal skin, removing the rivets p/n MS20470AD4-4 (see Figure 1). 4. Clean the reworked surfaces with Methyl-Ethyl-Ketone, or equivalent cleaning solvent, and treat them with Alodine 1200 (Specification MIL-C-5541) then with Epoxy Primer (Specification MIL-PRF-23377). First Issue dated 07 November 2017 Page 3 of 8

4 5. On workbench, trim the magnetometer support by removing the material as per Figure Restore magnetometer support surface finish with Alodine 1200 (Specification MIL-C- 5541) then with Epoxy Primer (Specification MIL-PRF-23377). 7. Position the magnetometer support on fuselage dorsal skin as per Figure 1, and install it by using rivets p/n MS20470AD Install the GMU 44 unit to the concerning support using screws p/n MS Connect the aircraft wiring harness to the Magnetometer GMU Reinstall the fairing at the fin forward base. 11. Re-connect battery cables (positive cable first) and re-install the baggage bulkhead. Figure 1 Relocation of Magnetometer GMU 44 First Issue dated 07 November 2017 Page 4 of 8

5 12. Perform the alignment and calibration of the inertial platform Garmin GRS77 / GMU44, in accordance with the following four steps: a. GRS77/GMU magnetic calibration. i. Start the engines in accordance with concerning procedure within AFM. NOTE Place the aircraft as far as possible from metallic masses, manholes, storm drains, ferrous railings, auxiliary power unit, and whatever ferrous material can alter the compass indication. ii. Align the aircraft with the magnetic NORTH point (±5 of deviation is allowed). Check the nose orientation with an operator using a sample compass and placed in the front of the aircraft at 10m, who aligns the sample compass viewfinder with the windshield central strut and aircraft vertical fin, to ensure the magnetic north point alignment. iii. Once aligned, restart Garmin PFD and MFD in configuration mode (pressing ENT when powering ON). iv. Select on PFD the page GRS / GMU CALIBRATION (see Figure 2). Figure 2 GRS/GMU Calibration page Magnetometer procedure v. Press in sequence 9, 10, 11 and 12 buttons (see Figure 3) to unlock the page. Figure 3 Password keys vi. Move the cursor to SELECT PROCEDURE field and select MAGNETOMETER, then press ENT. vii. Move the cursor to BEFORE CALIBRATION field. It will be displayed a checklist with all the actions to be considered before the calibration procedure. When each action has been completed, press ENT to continue with the following one. First Issue dated 07 November 2017 Page 5 of 8

6 viii. When CALIBRATE is blinking, press ENT to initialize the calibration procedure. ix. Follow the instructions by the system which will warn when moving/stopping the aircraft. At each instruction, move the aircraft clockwise; the system will warn when stopping. NOTE The use of a sample magnetic compass is recommended to perform correctly the aircraft rotation. Since difficult may arise from slowly moving the aircraft, the system may activate the HOLD POSITION command before properly terminating the aircraft moving. To avoid this, use an external reference (i.e. a sample compass) to rotate of 30 (±5 ) the aircraft within time limits warned by the system. x. Repeat the aircraft moving/stopping procedure until the system will advise that the calibration is successful. xi. When system will display the successful conclusion of the calibration operation, the AHRS will enter in normal mode. xii. Press ENT to end this calibration procedure. b. Engine run-up. i. Restart Garmin in configuration mode. ii. Select the GRS/GMU CALIBRATION page. iii. Press in sequence 9, 10, 11 and 12 buttons to unlock the page. iv. Move the cursor to SELECT PROCEDURE field and select ENGINE RUN-UP TEST. Press ENT to confirm. v. Move the cursor to BEFORE CALIBRATION field. It will be displayed a checklist with all the actions to be considered before the calibration procedure. When each action has been completed, press ENT to continue with the following one. vi. When CALIBRATE is blinking, press ENT to initialize the calibration procedure. vii. Wait a few seconds for a check list appearing on lower area of PFD. viii. Follow PFD instructions; PFD will advise how to change engine throttle from minimum to maximum and again to minimum, within about 1 minute. ix. When all the instructions have been performed, and with engines at low RPM, press ENT and then TEST COMPLETE will stop blinking. x. PFD will show if vibration test is successful. NOTE If test is not successful, the system will display the improper values. If test is not successful, repeat the procedure 3 (three) times. If it is still not successful, a troubleshooting is required to identify the root cause of vibration and the AHRS unit installation must be considered not reliable. First Issue dated 07 November 2017 Page 6 of 8

7 c. Magnetometer interference test (take a chronometer for the following): i. Restart Garmin in configuration mode. ii. Select the GRS/GMU CALIBRATION page. iii. Press in sequence 9, 10, 11 and 12 buttons to unlock the page. iv. Move the cursor to SELECT PROCEDURE field and select MAG INTERFERENCE TEST. Press ENT to confirm. v. Move the cursor to BEFORE CALIBRATION field. It will be displayed a checklist with all the actions to be considered before the calibration procedure. When each action has been completed, press ENT to continue with the following one. vi. When CALIBRATE is blinking, press ENT to initialize the calibration procedure. vii. Carry out the test as per test sequence prepared in accordance with the following Table 1 with a chronometer ready to begin recording the elapsed time. NOTE Ensure that the time equals zero moment corresponds with the moment PFD first displays the blinking TEST COMPLETE? message. Time from the beginning of the test [min:sec] Action 0:00 Start test 0:10 Navigation light ON 0:20 Navigation light OFF 0:30 Landing light ON 0:40 Landing light OFF 0:50 Taxi light ON 1:00 Taxi light OFF 1:20 Strobe light ON 1:40 Strobe light OFF 1:50 Flap actuator ACTIVATE 2:10 Flap actuator DEACTIVATE 2:20 Pitot heat ON 2:40 Pitot heat OFF 2:50 Propeller De Ice ON 3:10 Propeller De Ice OFF 3:20 Pneumatic De Ice ON 3.40 Pneumatic De Ice OFF 3:50 Fan Crew ON 4:00 Fan Crew OFF 4:10 Fan Passengers ON 4:20 Fan Passengers OFF 4:30 Fan heaters/defrost ON (if installed) 4:50 Fan heaters/defrost OFF (if installed) 5:00 Weather Radar ON (if installed) 5:20 Weather Radar OFF (if installed) 5:30 GIA63 (NAV/COM) ON 6:00 GIA63 (NAV/COM) OFF - Any additional item in your configuration ON - Any additional item in your configuration OFF Table 1 Test sequence First Issue dated 07 November 2017 Page 7 of 8

8 viii. Press ENT to terminate the procedure. TEST COMPLETE will stop blinking and the system will show if the test is passed successful. If the test fails, a troubleshooting is required to identify the root cause of the interference. Take note of the deviations registered during the test and the corresponding action and then contact Vulcanair Customer Support by means of the online form at the address section Support form. If the test passes, no further action is required for this test. ix. Press ENT key on PFD to conclude this procedure. 13. Perform the check of the inertial platform Garmin GRS77/GMU44 alignment, in accordance with the following procedures: a. Restart the PFD and MFD in normal mode. b. Properly align the aircraft along the four cardinal points (North, South, East and West). c. Fill the Table 2 and verify that all the values read on the HSI indicator (on Primary Flight Display) are identical to those reported on a reference sample compass (max acceptable deviation is ± 2 ). Real nose Nose orientation read orientation on HSI indicator Deviation NORTH 0 EAST 90 SOUTH 180 WEST 270 (1) (2) (2)-(1) Table 2 Check inertial platform Garmin GRS77/GMU44 alignment Part C Restoration of aircraft s airworthiness. 1. Update the Equipment List into the Aircraft Flight Manual to the latest revision and re-mark the items, as applicable. 2. Update the applicable Aircraft Maintenance Manual to the latest revision. 3. Record compliance with this Service Bulletin in the Aircraft Log-Book. 3. MATERIALS REQUIRED FOR THE MODIFICATION Commercially available materials required: - Rivet p/n MS20470AD4-4 (qty 4) - Methyl-Ethyl-Ketone or equivalent cleaning solvent. - Alodine 1200 (MIL-C-5541). - Epoxy Primer (MIL-PRF-23377). First Issue dated 07 November 2017 Page 8 of 8