SERVICE BULLETIN NO. 1200

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Date: May 29, 2009 (S) SUBJECT: LANDING GEAR MODIFICATION AND HARDWARE REPLACEMENT MODELS AFFECTED: SERIAL NUMBERS AFFECTED: PA-38-112 Tomahawk 38-78A0001 through 38-82A0122 COMPLIANCE TIME: PART I – LANDING GEAR MODIFICATION: To take place at the first occurrence of any one of the following events: 1. The next regularly scheduled maintenance event but not to exceed one hundred (100) hours time in service. 2. Immediately after a known hard landing is made. 3. Immediately after a landing is made while the aircraft is known to exceed the design landing weight. Compliance with PART 1 is a one time only requirement. PART II – LANDING GEAR HARDWARE INSPECTION: To occur periodically after completion of PART I, at a maintenance interval frequency not to exceed one hundred (100) hours time in service. PART III – LANDING GEAR HARDWARE REPLACEMENT: To occur periodically after completion of PART I, at a maintenance interval frequency not to exceed one thousand (1000) hours time in service, or after a known hard landing is made, or after a landing is made while the aircraft is known to exceed the design landing weight. APPROVAL: The technical content of this Service Bulletin has been shown to comply with the applicable Federal Aviation Regulations and is FAA approved. PURPOSE: An examination of the Tomahawk aircraft service history reveals that the bolts securing the main landing gear to the airframe can bend or break when subjected to repeated high loading conditions, resulting in landing gear failure. This service bulletin mandates a one-time modification to allow installation of higher strength bolts, and establishes maintenance schedules for recurring inspection and replacement of the landing gear attach bolts. Piper Aircraft, Inc. 2926 Piper Drive Vero Beach, Florida, U.S.A. 32960 (OVER) ATA: 3207 PIPER CONSIDERS COMPLIANCE MANDATORY SERVICE NO. 1200 BULLETIN INSTRUCTIONS: PART I – LANDING GEAR MODIFICATION: 1. Order and install “KIT – PA38 LANDING GEAR HARDWARE REPLACEMENT”, Piper part number 88455-002, one per aircraft. This kit provides parts and instructions for installing replacement hardware that fasten the main landing gear to the airframe. NOTE: Verify compliance with Piper Service Bulletin 673 (latest revision) prior to installing 88455-002. 2. Make an appropriate logbook entry indicating compliance with Part I of this Service Bulletin. PART II – LANDING GEAR HARDWARE INSPECTION: 1. Place aircraft on jacks. Refer to Piper Maintenance Manual “TOMAHAWK MAINTENANCE MANUAL – PA-38-112, Piper part number 761-660, Chapter 7, “LIFTING AND SHORING”. 2. Remove main landing gear fairings to gain access to the landing gear attach bolts, and retain fairings and fairing mounting hardware for reinstallation. 3. Remove safety wire from the landing gear attach bolts (quantity 3 per side, total 6 per aircraft) and discard. Check bolts for proper torque as shown in Figure 1. 4. Install new safety wire (MS20995C41), reinstall fairings, and remove aircraft from jacks. 5. Make an appropriate logbook entry indicating compliance with Part II of this Service Bulletin. PART III – LANDING GEAR HARDWARE REPLACEMENT: 1. Place aircraft on jacks. Refer to Piper Maintenance Manual “TOMAHAWK MAINTENANCE MANUAL – PA-38-112, Piper part number 761-660, Chapter 7, “LIFTING AND SHORING”. 2. Remove main landing gear fairings to gain access to the landing gear attach bolts, and retain fairings and fairing mounting hardware for reinstallation. 3. Remove safety wire from the landing gear attach bolts and discard. Remove the bolts from the aircraft and discard (quantity 3 per side, total 6 per aircraft), taking care to note and record the existing stack-up of shims and washers. Remove and discard existing NAS577B7A barrel nuts (quantity 1 per side, total 2 per aircraft). 4. Install new replacement hardware, as shown in Figure 1 and as listed in Materials Required - Table 4. All other components that are free of damage or corrosion may be re-used at their original locations. Torque bolts according to the following procedure: a) Draw up pairs of NAS6606HL15 bolts evenly, 1 or 2 turns maximum per bolt, alternating back and forth until bolts are snug. Install (1 each side) NAS6607H22 bolt, and tighten until snug. Torque should build up gradually for all bolts. An abrupt buildup indicates threads are bottoming in the barrel nut. b) With all bolts installed and snug, torque the (2 each side) NAS6606HL15 bolts 160 to 200 inch-pounds, and torque the (1 each side) NAS6607H22 bolts 270 to 300 inch-pounds. Examine bolt thread penetration during and after torquing. • For the (2 each side) NAS6606HL15 bolts, the end of bolt must be at least flush with barrel nut after torquing. If bolt extends into clearance hole, or threads bottom out as described above, add additional AN960-616 or AN960-616L washer under bolt head to achieve proper bolt grip. The saddle clamp and shim should fit snugly against the wing. See Table 1 for interchangeability with NAS1149 washers. • For the (1 each side) NAS6607H22 bolts, at least one complete bolt thread must protrude visibly through the barrel nut after torquing. If bolt extends into clearance hole, or threads bottom out as described above, add additional AN960-716 or AN960-716L washer under bolt head to achieve proper bolt grip. See Table 1 for interchangeability with NAS1149 washers. SERVICE BULLETIN NO. 1200 PAGE 2 OF 5 Table I Interchangeability The AN960 series washers were installed at the factory, and remain acceptable for continued use. However, AN960 washers are inactive for new design, so service spares replacements may not be readily available. The table above specifies the replacement NAS1149 washers that can be used interchangeably with the AN960 washers. Inactive Part Number Replacement Part Number AN960-616L NAS1149F0632P AN960-616 NAS1149F0663P AN960-716L NAS1149F0732P AN960-716 NAS1149F0763P INSTRUCTIONS: (Continued)