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32-10-00 LANDING GEAR SYSTEM — GENERAL DESCRIPTION

This chapter covers the design, operation, maintenance, and inspection requirements for the main and nose landing gear systems installed on the aircraft. All procedures defined herein are applicable to aircraft serial numbers 0001 through 0847 unless otherwise stated in an applicable Service Bulletin (SB) or Airworthiness Directive (AD).

1.1 SYSTEM IDENTIFICATION. The aircraft landing gear assembly consists of three main retractable units — two main gear assemblies (left-hand and right-hand) and one nose gear assembly — each identified by a unique part number per S1000D data module DMC-AMM-32-10-01. Component identification plates are affixed to each structural attachment fitting and must remain legible at all times.

1.2 SYSTEM DESCRIPTION. The landing gear system is a hydraulically actuated, electrically controlled tricycle-type configuration. The main gear units retract inboard into the wing-fuselage fairing, while the nose gear retracts forward into the nose bay. Each gear is equipped with an over-centre locking mechanism and a dedicated uplatch/downlatch assembly verified by proximity sensors.

The gear is operated by the primary hydraulic system (System A, 3000 psi nominal). In the event of primary system failure, the alternate extension system (AES) uses stored nitrogen pressure to release uplocks and allow gravity-assisted extension. The gear will free-fall and lock down without hydraulic pressure.

1.3 APPLICABLE DOCUMENTS. The following documents are referenced throughout this chapter:

— AMM Chapter 12: Servicing — Hydraulic fluid replenishment

— AMM Chapter 29: Hydraulic Power — Pressure limits, torque values, and sealing procedures

— AMM Chapter 20: Standard Practices — Fastener torque tables

— SRM Chapter 32: Structural Repair Manual — Allowable damage limits

32-10-01 SCHEDULED MAINTENANCE REQUIREMENTS

2.1 MAINTENANCE INTERVALS. Scheduled maintenance intervals are defined in accordance with the Airworthiness Limitations Section (ALS), with primary component inspection intervals not exceeding 600 flight hours or 12 calendar months, whichever occurs first.

2.2 TASK ESCALATION. Operators approved under an MSG-3 derived Maintenance Review Board (MRB) report may apply for interval escalation upon submission of reliability data covering a minimum of 1,000 fleet flight hours on the applicable task. Escalation requests must be submitted to the Type Certificate Holder (TCH) for review.

2.3 LUBRICATION. All landing gear pivot pins, torque links, and retraction actuator bearings must be lubricated per the lubrication chart in Figure 32-10-01-991-001. Use only approved grease conforming to MIL-PRF-81322 or equivalent unless otherwise specified.

2.4 WEAR LIMITS. Bushing wear limits are defined in Table 32-10-01-1. Assemblies exceeding published wear limits must be removed from service and replaced with serviceable units prior to the next flight. No in-situ repair of worn bushings is permitted.

32-10-01 HYDRAULIC ACTUATION AND SAFETY PRECAUTIONS

3.1 SYSTEM PRESSURE. The landing gear actuation circuit is supplied by Hydraulic System A at a nominal operating pressure of 3,000 psi (20.7 MPa). Maximum system relief valve setting is 3,300 psi (22.8 MPa). Do not apply hydraulic pressure to the gear circuit when personnel or equipment are within the gear sweep zone.

3.2 DEPRESSURISATION PROCEDURE. CAUTION: Hydraulic system pressure must be fully relieved prior to any component removal or line disconnection. Confirm zero pressure by observing the hydraulic system pressure gauge on the maintenance panel (P61) before proceeding. Specific torque values and safety warnings for hydraulic line disconnection are defined in AMM Chapter 29 — these values are not reproduced in this revision of Chapter 32.

3.3 GEAR SAFETY PINS. Before any maintenance requiring gear movement or access to wheel wells, install all three gear safety pins (P/N 5820-AMM-32-PIN-A). Pin stowage locations are at Maintenance Access Panel 322 AL (nose) and 322 BL/BR (main). A placard must be posted on the cockpit gear lever when pins are installed.

3.4 ACTUATOR REMOVAL. The retraction actuator may be removed with the gear in the down and locked position only. Remove actuator attachment bolts (4×) using the torque wrench set-up defined in AMM Chapter 20 Standard Practices, Table 20-10-00-1. Support the actuator with an approved sling assembly before removing the final bolt to prevent structural damage to the aft attachment lug.

32-20-00 GROUND HANDLING AND TOWING PROCEDURES

[§32-20-00 Ground handling and towing procedures — content not found in this revision. Expected content: towing speed limits, nose gear steering disconnect procedure, tow bar attachment/removal, pushback clearances, and personnel safety zones.]

NOTE: Until this section is populated in the next document revision, refer to the applicable Ground Handling Manual (GHM) Chapter 9 for interim guidance. Maintenance control must be notified of this gap before any towing operations are performed.

32-30-00 FAULT ISOLATION — LANDING GEAR SYSTEM

5.1 GENERAL. This section provides systematic fault isolation procedures for the landing gear system. All troubleshooting must be performed in accordance with the general troubleshooting policy defined in AMM Chapter 01. Personnel performing fault isolation must hold an appropriate licence endorsement for the aircraft type.

5.2 FAULT ISOLATION SEQUENCE. Fault isolation for landing gear system components follows the standard maintenance manual sequence: verify cockpit warning light indications, perform Built-In Test (BIT) via the centralized maintenance computer (CMC), isolate fault to line-replaceable unit (LRU) level using the applicable fault code cross-reference table, replace the identified LRU with a serviceable unit, and perform a ground operational test to verify rectification.

5.3 CMC FAULT CODES. Landing gear-related CMC fault codes are prefixed LG-. A full listing is provided in the Fault Reporting Manual (FRM) Chapter 32. Common codes include LG-001 (nose gear up-lock proximity sensor fault), LG-014 (main gear retraction actuator position disagreement), and LG-031 (alternate extension system pressure low).

5.4 HYDRAULIC LEAKAGE. If hydraulic fluid is observed in the wheel well after gear retraction, isolate to actuator shaft seal, return line O-ring, or selector valve before flight. Classification of leaks follows AMM Chapter 05 definitions — seepage is acceptable for dispatch; a drip rate exceeding 1 drop per 30 seconds requires rectification before further flight.

5.5 PROXIMITY SENSOR RIGGING. If a gear-not-locked warning cannot be cleared by LRU replacement, verify proximity sensor gap settings per the rigging tolerance table in Figure 32-30-00-991-003. Incorrect gap will cause intermittent proximity sensor faults that are not repeatable during ground test.

32-40-00 POST-MAINTENANCE INSPECTION REQUIREMENTS

[§32-40-00 Post-maintenance inspection checklist — content not found in this revision. Expected content: sign-off criteria, gear retraction test procedure, door clearance checks, fluid level verification, and return-to-service certification requirements.]

NOTE: Post-maintenance inspection requirements must be completed and documented in the aircraft maintenance record before a Certificate of Release to Service (CRS) is issued. Refer to Quality Procedures Manual QPM-32-04 for interim sign-off requirements pending update of this section.

32-50-00 APPROVED CONSUMABLES AND SPECIAL TOOLING

6.1 HYDRAULIC FLUID. System A is filled with hydraulic fluid conforming to BMS 3-11 Type IV (Skydrol LD-4 or equivalent). Do not mix fluid types. Contaminated fluid requires complete system flush per AMM Chapter 29-00-00.

6.2 SPECIAL TOOLING. The following special tools are required for procedures in this chapter:

— 32-AMM-T001: Gear pin installation/removal tool

— 32-AMM-T002: Torque link alignment fixture

— 32-AMM-T003: Wheel well access platform (or approved equivalent)

— 32-AMM-T004: Proximity sensor gap gauge set (0.050–0.250 in range)

6.3 FASTENERS. All fasteners removed during landing gear maintenance must be replaced with new items unless a serviceable reuse inspection is performed in accordance with AMM Chapter 20. Thread-locking compound (Loctite 243 or approved equivalent) is required on all self-locking nut replacements where specified in the illustrated parts catalogue (IPC).