# SERVICE BULLETIN

SERVICE BULLETIN NO: 32-021 REF NO: 220 MODIFICATION NO: EC 08-0766 ATA CHAPTER: 32

DATE: Nov 21/08 SERVICE BULLETIN No. 32-021 REV No. PAGE 1 of 8 PILATUS AIRCRAFT LTD. CH-6371 STANS, SWITZERLAND

LANDING GEAR - NOSE WHEEL STEERING REPLACEMENT OF THE CRANK BAR ASSY 1. Planning Information A. Effectivity: All PC-12 and PC-12/45 aircraft from MSN 101 thru MSN 299. B. Concurrent Requirements None. C. Reason (1) Problem Failure of the nose wheel steeri ng system because of fatigue cracking of the torque tube in the crank bar assy. (2) Cause Some torque tubes were bored off-center during manufacture. This results in a reduced wall thickness at one side of the torque tube. The torque tube can also crack at the bolt holes for the lever attachment bolt. (3) Solution Install a new crank bar assy which is manufactured to a higher standard. D. Description This Service Bulletin gives the data and instructions necessary to replace the crank bar assy. E. Compliance Mandatory. At the next scheduled aircraft inspection. F. Approval The technical content of this Se rvice Bulletin is approved under the authority of DOA No. EASA. 21J. 357. PILATUS advises Operators/Owners to check with their local Airw orthiness Authorities for any changes, local regulations or sanctions that may affect the embodiment of this Service Bulletin.DATE: Nov 21/08 SERVICE BULLETIN No. 32-021 REV No. PAGE 2 of 8 

## SERVICE BULLETIN G. Manpower

H. Weight and Balance (1) Weight Change Not affected. (2) Moment Change Not affected. I. Electrical Load Data Not applicable. J. Software Not changed. K. References Aircraft Maintenance Manual (AMM): 12-A-07-10-00-00A-901A-A, 12-A-06-20-00-00A-040A-A, 12-A-20-31-00A-070A-A, 12-A-32-50-00-00A-903A-A. L. Publications Affected Not applicable. M. Interchangeability of Parts A torque tube P/N 532.50.12.047 must not be installed on a Post SB 32-021 aircraft. Man-hours Removal 0.75 Installation 1.25 Test 0.50 Close Up 0.25 TOTAL MAN-HOURS 2.75DATE: Nov 21/08 SERVICE BULLETIN No. 32-021 REV No. PAGE 3 of 8 

## SERVICE BULLETIN 2. Material Information Operators should send orders for Service Bulle tin Modification Kits, to their Authorized Pilatus Service Center or:

Operators are requested to advise Pilatus Ai rcraft Ltd, of the Manufacturer’s Serial Number (MSN) and the flying hours and landings of aircraft which are affected by this Service Bulletin.

PILATUS AIRCRAFT LTD., CUSTOMER SUPPORT MANAGER, CH-6371 STANS, SWITZERLAND General Aviation: Tel: + 41 41 619 6208 Fax: + 41 41 619 7311 eMail: SupportPC12@pilatus-aircaft.com PILATUS BUSINESS AIRCRAFT LTD., PRODUCT SUPPORT DEPARTMENT 11755 AIRPORT WAY BROOMFIELD, CO 80021. UNITED STATES OF AMERICA Tel: 303 465 9099 Fax: 303 465 6040 eMail: Productsupport@PilBal.com

PILATUS AUSTRALIA (PTY.) LTD, 17 JAMES SCHOFIELD DRIVE, ADELAIDE AIRPORT SA 5950, AUSTRALIA Tel: (08) 8234 4433 Fax: (08) 8234 4499 Free Call: 1800 445 007 eMail: info@p ilatus.com.au A. Material - Price and Availability

B. Warranty Credit will be issued for all affected aircraft on approval of a warranty claim, provided that: • The work is done by an authorized servic e center during or before the next scheduled aircraft inspection but not later than 12 cale ndar months after the effective date of this Service Bulletin • The removed parts are sent to Pilatus and receipt is confirmed. C. Material Necessary for Each Aircraft (1) Material to be Procured Modification Kit No. 500.50.12.334 consists of these parts: Modification Kit Number Price Availability 500.50.12.334 Contact address above Contact address above

New Part No. Description Old Part No. Qty Disp. Code Fig Item 532.50.12.064 Torque Tube 532.50.12.047 1 R 1 20 Disposition Codes: D - Discard / R - Return to PilatusDATE: Nov 21/08 SERVICE BULLETIN No. 32-021 REV No. PAGE 4 of 8 

## SERVICE BULLETIN

(2) Operator Supplied Parts

(3) Operator Supplied Materials (Ref. AMM 12-A-20-31-00A-070A-A ) .

D. Material Necessary for Each Spare Not applicable. E. Reidentified Parts Not Applicable. F. Tooling - Cost and Availability Not Applicable.

532.50.12.051 Lever 532.50.12.051 1 R 1 12 932.19.60.801 Bolt, Hex, Cl Tol, Cres (AN174C13A) 932.19.60.801 1 D 1 1 938.77.11.114 Washer, Flat (NAS1149F0432P) 938.77.11.114 1 D 1 5 938.07.68.305 Nut, Hex, Slflkg (MS21045-4E) 938.07.68.305 1 D 1 6

Part No. Description Qty Remarks 940.17.02.236 Pin, Cotter, Steel 1 MS24665-210 940.17.02.226 Pin, Cotter, Steel 2 MS24665-134

Material No. Description Qty Remarks P01-008 Solvent A/R P02-031 Absorbent Paper A/R P04-012 Corrosion Preventative A/R

- Orcotape (Pilatus P/N 917.40.61.113) A/R If installed. New Part No. Description Old Part No. Qty Disp. Code Fig Item

Disposition Codes: D - Discard / R - Return to PilatusDATE: Nov 21/08 SERVICE BULLETIN No. 32-021 REV No. PAGE 5 of 8 

## SERVICE BULLETIN 3. Accomplishment Instructions A. Removal (Ref. Fig. 1) (1) Lift the aircraft on jacks (Ref. AMM 12-A-07-10-00-00A-901A-A ). (2) Open and safety the circuit breaker: HYDR CTL (NON ESSENTIAL BUS) (3) Make sure the nose wheel is in the neutral position and there is no load on the spring strut (17). (4) Open the access panel 11AL (Ref AMM. 12-A-06-20-00-00A-040A-A ). (5) If necessary, remove the Orcotape and insulation to get a ccess to the nut (4). (6) Remove the cotter pin (7), the nut (8) and the washer (9). (7) Remove the bolt (11) and disconnect the rod (10). (8) Remove and discard the nut (6), the washer (5) and the bolt (1) (9) Make sure that the lever (12) can turn on the torque tube (20). If you cannot turn the lever (12) with your hand: (a) Lower the aircraft until the nose wheel is on the ground and cannot turn. (b) Use force to make the lever (12) free to turn. NOTE: You can use penetrating oil to help to release the lever. (c) When you can turn the lever (12) on the torque tube (20), lift the nose wheel. (10) Remove the cotter pin (15), the nut (14) and the washer (13). (11) Remove the bolt (19) and disconnect the spring strut (17). Collect the washers (16) and (18). (12) Remove the cotter pin (3), the nut (4) and the washer (2). Make a note of the installation position of the washer (2). (13) Hold the lever (12) and remove the torque tube (20) from the lever and bearings. (14) Keep the lever (12) and the torque tube (20) and send them to Pilatus Aircraft Ltd. B. Installation (Ref. Fig. 1) (1) Apply a thin layer of corrosion preventative (Material No. P04-012) to the inside mating surface of the lever (12) (2) Hold the lever (12) (P/N 532.50.12.051) between the bearings and install the torque tube (20) (P/N 532.50.12.064). Make sure the lever (12) is installed in the correct position as shown in Fig. 1. (3) Install the bolt (1) (P/N 932.19.60.801) , the washer (5) (P/N 938.77.11.114) and the nut (6) (P/N 938.07.68.305).DATE: Nov 21/08 SERVICE BULLETIN No. 32-021 REV No. PAGE 6 of 8 

## SERVICE BULLETIN (4) Use the absorbent paper (Material No. P02-03 1) and the solvent (Material No. P01-008) to remove unwanted corrosion preventative from the torque tube (20). (5) Install the washer (2) (in the position noted in the removal procedure), the nut (4) and the new cotter pin (3). (6) Connect the spring strut (17) with the two washers (16) and (18) and the bolt (19). (7) Install the washer (13), the nut (14) and the new cotter pin (15). (8) Connect the rod (10) with the bolt (11). (9) Install the washer (9), the nut (8) and the new cotter pin (7). C. Test (1) Do the adjustment/test of the nose wheel steering (Ref. AMM. 12-A-32-50-00-00A-903AA ) D. Close Up (1) If necessary, install the insulation and the Orcotape. (2) Close the access panel 11AL (Ref AMM. 12-A-06-20-00-00A-040A-A ). E. Documentation Make an entry in the Aircraft Logbook that this Service Bulletin has been incorporated.DATE: Nov 21/08 SERVICE BULLETIN No. 32-021 REV No. PAGE 7 of 8 

## SERVICE BULLETIN

Crank Bar Assy - Removal/Installation Figure 1 10 9 8 7

13 6 5 1

12 2

4 3

11SB1801 

# A B



# B A

14

16

17 18 19 20

15 THE NEW TORQUE TUBE P/N 532.50.12.064 HAS NO GROOVEDATE: Nov 21/08 SERVICE BULLETIN No. 32-021 REV No. PAGE 8 of 8 

## SERVICE BULLETIN

INTENTIONALLY BLANK