Instructions for Continued Airworthiness for “The Alaska Rack” External Load Racks

Robinson R44 Maintenance Manual and the approved installation manual for this system. With the exception of the racks themselves, maintenance with this installation will generally include the removal and replacement of parts. The maintenance of the racks themselves is minor. Maintenance personnel shall use normal aircraft practices as the criteria for maintenance of the above elements. These practices are identified in AC 43-13 1-B Chapter 4, Section 5 and Chapter 7, Sections 3, 4, and 5. Although not required additional maintenance data may also be found in the Robinson Helicopter R44 Maintenance Manual, Section 2 Inspection, Parts 2.100 and 2.300. General Removal & Replacement Instructions Detail removal and replacement instructions are below. When the external load racks are removed, the installation hardware and rack mounts shall be inspected. Although under normal use these should not need replacement, if any of the mounts or hardware are damaged or worn they must be replaced. Critical Note When either removing or installing the below mounts and hardware it is imperative the aircraft components be supported and stabilized while any bolts or hardware are removed and installed. This is especially critical for the left and right upper rear mounts, and the lower landing gear tabs. Alaska Rack, ICA Revision #2: March 2016 page 6 of 12 Hardware Replacement Criteria Bolts, Nuts, Washers – Must meet new specifications for fit, shank diameter and thread quality. Bolts and/or nuts shall be replaced if any threads or thread locking is damaged. Light scuffing of cad plating due to removal or use is acceptable. See AC43.13-1B, Chapter 7, Section 3, 4, and 5 for criteria. Rod Ends and Spherical bearings – Maximum radial play on rod ends is .010 inch; maximum axial play on rod ends is .020 inch. (Robinson R44 Maintenance Manual, Section 2, 2.122) Torque Criteria (Torque Criteria from R44 Maintenance Manual, Section 1, 1.320) Fastener Size Dry Torque (in.-lb.) AN 3 Bolts 10-32 50 AN4 Bolts 1/4-28 120 AN44 Eyebolts, 6605 Bolts 5/16-24 240 6607 Bolts 7/16-20 665 Upper Forward Mount (Left) See picture #1 in Appendix A for location and installation reference. Refer to Robinson Helicopter Co. R44 Illustrated Parts Catalog Figure 8-1 for additional location reference. 1. Remove AN3 bolts, nuts, and washers from triangular rack support tab at lower edge of main fuel tank attachment to fuselage. (These bolts replace Item #1, MS27039C0807 in R44 parts manual). 2. If the rack support tab is to be permanently removed, replace the AN3 bolts with shorter AN3 bolts so as to maintain adequate grip length. Replace washers and nuts. Torque to 50 in. lb. 3. If the rack support tab is to be replaced, reinstall new tab with either existing or new hardware. Torque to 50 in. lb. Alaska Rack, ICA Revision #2: March 2016 page 7 of 12 Upper Forward Mount (Right) See picture #1 in Appendix A for location and installation reference. Refer to Robinson Helicopter Co. R44 Illustrated Parts Catalog Figure 53-15 for additional location reference. 1. Remove AN3 bolts, nuts, and washers from rack support tab at forward horizontal firewall attachment to fuselage. (These bolts originally replaced item #1 (MS27039C0807), item 14 (NAS1149FN832P) and item #15 (MS21042L08 in R44 parts manual). 2. If the rack support tab is to be permanently removed, replace the AN3 bolts with shorter bolts so as to maintain adequate grip length. Replace washers and nuts. Torque to 50 in. lb. 3. If the rack support tab is to be replaced, reinstall new tab with either existing or new hardware. Torque to 50 in. lb. Upper Rear Mount (Left) See picture #1 in Appendix A for location and installation reference. Refer to Robinson Helicopter Co. R44 Illustrated Parts Catalog Figure 53-19 for additional location reference. 1. Remove AN44-15A eyebolt and 1 inch bushing. (This eyebolt and bushing replace item #32, NAS6605-6 in R44 parts manual). 2. If this upper rear mount is to be removed replace with NAS6605-6 bolt as specified in original R44 parts manual. Torque to 240 in. lb. 3. If this eyebolt and bushing are to be replaced, install new eyebolt and bushing. Torque to 240 in. lb. Upper Rear Mount (Right) See picture #1 in Appendix A for location and installation reference. Refer to Robinson Helicopter Co. R44 Illustrated Parts Catalog Figure 53-19 for additional location reference. 1. Remove AN44-16A eyebolt and 1 inch bushing. (This eyebolt and bushing replace item #13, NAS6605-4 in R44 parts manual. 2. If this upper rear mount is to be removed, replace it with NAS6605-4 as specified in original R44 parts manual. Torque to 240 in. lb. 3. If this eyebolt and bushing are to be replaced, install new eyebolt and bushing. Torque to 240 in. lb. Alaska Rack, ICA Revision #2: March 2016 page 8 of 12 Lower Forward Mount (Left and Right) See picture #1 in Appendix A for location and installation reference. Refer to Robinson Helicopter Co. R44 Illustrated Parts Catalog Figure 53-19 for additional location reference. 1. Remove AN44-20 eyebolt from either left and/or right lower forward mounts. These were originally item #15 (NAS6605-4), and washer #20 (NAS1149F0532P) in the R44 parts manual. 2. If this lower forward mount is to be removed, replace it with NAS6605-4 bolt and washers as specified in original R44 parts manual. Torque to 240 in. lb. 3. If this eyebolt is to be replaced, install new eyebolt, washer and nut, and torque to 240 in. lb. Lower Rear Mount (Left and Right) See picture #1 in Appendix A for location and installation reference. Refer to Robinson Helicopter Co. R44 Illustrated Parts Catalog Figure 32-1 for additional location reference. NOTE Pay particular attention to the special washer C141-1, item #22, on each side of the landing gear fitting. This is a special washer that allows the “rod end” to rotate. This special washer must remain correctly inplace. 1. Remove bolt item #23 (NAS6607-52) from left and/or right elbow to strut. 2. If the steel strap tab is to be removed, reinstall bolt, and standard hardware as per the R44 IPC. Torque as per R44MM. 3. If the steel strap is to be replaced, install new strap, bolt, washer, and nut, and torque to 665 in. lb. Rack Removal Procedures 1. Remove nuts and washers from each of the four legs of the rack attach points. 2. While lifting the racks, remove the AN4-7 bolts from the rod ends and attach mounts. 3. Swing the rack away from the aircraft and replace hardware in the rod ends for safekeeping. 4. Complete weight and balance calculation for rack removal. Alaska Rack, ICA Revision #2: March 2016 page 9 of 12 Rack Reinstallation Procedures 1. Leave rod ends on rack loose until final installation adjustments have been made. 2. Lift racks into place and temporarily secure with AN4 bolts through rod ends. As necessary align rods ends on rack so as to line up with mounting plates and hardware on aircraft. Do not install nuts or washers at this time. 3. Folding Racks Only: Leave the AN3 attach bolts at the lower end of the vertical legs loose until the rack is secure on the aircraft. Then tighten bolts using above torque criteria. 4. After rods ends on rack have been adjusted for best fit to attach points install AN4-7 bolts, MS21042L4 nuts, and washers to secure racks. As needed, wide area washers maybe used under the head of the bolt or nut, or between the rod end at rack attach points. Torque to 120 in. lbs. 5. Secure locking nut on the rack rod ends. 6. Folding Racks Only: Secure AN3 bolts at the lower end of the vertical rack legs. 7. Confirm installation of safety placard “Maximum Weight – 150 lbs.” on each rack. 8. Confirm installation of cockpit placard in clear view of pilot at all times during operation with the cargo racks installed: Approved Cargo Envelope Cargo carried on the external load racks outside the “approved Cargo envelope” limits of the Pilot Operating Handbook Flight Manual Supplement, places the aircraft within the FAR Part 133 Requirements for Class A External Loads. In this case, the Applicable essential crew limitations apply. These crew limitations do not apply provided the cargo is within the “approved cargo envelope” limits. 9. Complete weight and balance calculation for rack installation. Alaska Rack, ICA Revision #2: March 2016 page 10 of 12 6. Airworthiness Limitations The Airworthiness Limitations section is FAA approved and specifies maintenance required under 14 CFR 43.16 and 91.403, unless an alternative program has been FAA approved. 7. Weight and Balance Following is the net weight increase associated with the installation of the external racks Installation Weight Longitudinal Lateral Arm Moment Arm Moment Left Rack 12 lbs + 109 in. +1308 - 30 inches -360 Right Rack 12 lbs + 109 in. +1308 +30 inches +360 Note: The maximum fore/aft CG, and the maximum left/right CG as per the Pilot Operating Handbook must never be exceeded. For any flight load refer to Pilot Operating Handbook for proper weight and balance limitations. 8. Cleaning Requirements The rack installation does not require a significant amount of cleaning. The rack attach fittings and the rack itself shall be kept clean so that they may be inspected for preflight. Cleaning can be accomplished with soap and water during normal external aircraft washing. 9. Adjustments Once mounted to the aircraft the racks should not require any adjustment. 10. Special Tools Installation of the racks does not require the use of any special tools. Installation maybe accomplished with standard mechanics hand tools. 11. Revisions A log of revisions section is included in these instructions and will be utilized to document any revisions. Change proposals should be submitted to: Alaska Rack 3811 Laron Lane Anchorage, Alaska 99504 Alaska Rack, ICA Revision #2: March 2016 page 11 of 12 12. Parts Breakdown Parts and materials list for the complete rack installation is as follows. Hardware and Supplies included in the Rack Kit Amount Part Number Description Rack Attachment fittings 1 AR-1 Left Rack 1 AR-1F Folding Rack Left (only included in folding rack kit) 1 AR-2 Right Rack 1 AR-2F Folding Rack Right (only included in folding rack kit) 1 AR-3 Left Upper Tab 1 AR-4 Right Upper Tab 2 AR-5 Landing Gear Tab 2 AR-6 1 inch bushings Hardware necessary to attach rack fittings 2 AN44-20A Eyebolt – left/right lower 1 AN44-17A Eyebolt – right upper 1 AN44-16A Eyebolt – left lower 4 MS20002C5 or AN960-516 Washer – for eyebolts (as necessary) 6 AN3-6 Bolts – left/right upper forward tabs 6 AN960-316L Washers 6 MS21042L3 Nuts 2 AN960-716L Washers (as needed for landing gear tab) Hardware screwed into Rack Legs 8 MSM4 Rod end 8 AN316-4R Jam nut (locking nut for MSM4 rod ends) Hardware to attach racks to fittings 8 AN4-10A Bolt 8 365-428A Fiber Lock Nut 8 AN960-416 Washer 8 AN970-4 Large area washer Folding Style Racks Only: Leg Hardware 4 AN3-7A Bolt 4 365-1032A Fiber Lock Nut 4 AN960-316 Washer Paper Work 1 Cockpit loading label 1 STC --- Stamped with numbers 1 Installation Instructions 1 ICA 1 POH supplement Note: Additional washers may be required, or longer bolts may be needed for the installation to provide adequate clearance or required thread length. This is allowed provided the installation follows the direction provided in AC43-13. Alaska Rack, ICA Revision #2: March 2016 page 12 of 12 Appendix A Left Side Alaska Rack Installation Note Installation of the racks and fixtures to the left and right side of the aircraft are almost identical. This picture is of the left side of the aircraft. Right side installation is identical, but mirror image.