1、_SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising theref
2、rom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2009 SAE International All rights reserved. No part of this publication ma
3、y be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: 724-776-4970 (outside USA)
4、Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/ARP1311CAEROSPACERECOMMENDEDPRACTICEARP1311C Issued 1979-03 Reaffirmed 2004-06 Revised 2009-02 Sup
5、erseding ARP1311B (R) Landing Gear Structures and Mechanisms RATIONALEThis document defines the aircraft industry recommended practice for the design and verification of landing gear structures and mechanisms. TABLE OF CONTENTS 1. SCOPE 31.1 Purpose . 32. APPLICABLE DOCUMENTS 32.1 SAE Publications .
6、 32.2 U.S. Government Publications 42.3 ANSI Publications . 52.4 FAA Publications . 52.5 EASA Publications 62.6 Other Publications . 63. DESIGN REQUIREMENTS 63.1 General Structural Requirements . 63.1.1 Structural Capacity 63.1.2 Structural Analysis 63.1.3 Spring Rates . 103.2 Energy Absorption. 103
7、.2.1 Capacity 103.2.2 Dynamic Stability . 103.2.3 Piston Diameter Sizing 103.2.4 Piston Stroke Assessment 113.2.5 Rebound Damping 113.2.6 Extension to Touchdown Time 113.2.7 Orifices 113.2.8 Metering Pins 123.2.9 Oil Content 123.2.10 Interconnection of Internal Chambers . 123.2.11 Servicing . 123.2.
8、12 Gas Charging Ports 133.2.13 Static and Dynamic Seals . 133.2.14 Hydraulic Fluids . 133.2.15 Scraper Rings . 143.2.16 Dynamic Sealing Surfaces 143.2.17 Sliding Bearings 143.2.18 Full Travel Stops . 153.2.19 Gas Content 15Copyright SAE International Provided by IHS under license with SAENot for Res
9、aleNo reproduction or networking permitted without license from IHS-,-,-SAE ARP1311C - 2 -3.3 Retraction Mechanism Elements 153.3.1 Downlock Mechanisms . 153.3.2 Gear Retraction and Extension . 163.3.3 Downlock Position Verification 163.3.4 Ground Safety Locking . 173.3.5 Uplock . 173.4 Elements Int
10、erfacing with Landing Gear Systems, Airframe and Other Units 173.4.1 Axles 173.4.2 Brake Mounting . 173.4.3 Airframe Attachments . 173.4.4 Joint Lubrication 173.4.5 Towing . 183.4.6 Jacking 183.4.7 Catapulting 183.4.8 Tie-Down . 183.5 Material and Process Requirements . 183.6 Environmental Compatibi
11、lity . 183.7 Miscellaneous Elements or Features 183.7.1 Interchangeability 183.7.2 Adhesive Sealants 183.7.3 Torsional Resistance of Locking Devices . 193.7.4 Nameplate . 193.7.5 Standard Tools 193.8 Hydraulic Actuators . 193.8.1 Retract Actuators in Tension . 193.8.2 Retract Actuators in Compressio
12、n 203.8.3 Internal Locking Design 203.8.4 Lock Actuators 213.8.5 Steering Actuators. 213.8.6 Landing Gear Door Actuators . 213.8.7 Truck Position Actuators . 224. DESIGN VERIFICATION 224.1 Preproduction Testing and Inspections 224.1.1 Examinations and Inspections 224.1.2 Dynamic Leakage Tests . 234.
13、1.3 Static Leakage Tests 244.1.4 Development Drop Testing . 244.1.5 Verification of Servicing Procedure . 244.1.6 Verify Application of New Designs 244.2 Qualification Testing . 254.2.1 Examination of Product . 254.2.2 Pressure Tests 254.2.3 Drop Testing 254.2.4 Fatigue Testing . 264.2.5 Static Stre
14、ngth Tests . 264.2.6 Endurance Testing 274.2.7 Environmental and Vibration Testing 284.3 Production Acceptance Testing and Verification 294.3.1 Inspections 294.3.2 Dimensional Checks (static) . 294.3.3 Verify Correct Servicing, Adjustments and Fluid Levels . 294.3.4 Static Leak Tests . 304.3.5 Prepa
15、ration for Shipping or Storage . 314.4 Flight Testing . 315. NOTES 32TABLE 1 DYNAMIC SEAL SPECIFICATIONS 14Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE ARP1311C - 3 -1. SCOPE This SAE Aerospac
16、e Recommended Practice (ARP) applies to landing gear structures and mechanisms (excluding wheels, tires, and brakes and other landing gear systems) for all types and models of civil and military aircraft. All axles, wheel forks, links, arms, mechanical and gas/oil shock struts, downlock and uplock a
17、ssemblies, braces, trunnion beams, and truck beams etc., that sustain loads originating at the ground, and that are not integral parts of the airframe structure, should be designed and validated in accordance with this document. Hydraulic actuators (retraction, main and nose gear steering, positioni
18、ng, damping, etc.) should also be included in this coverage. System level, non-structural components such as retraction/extension valves, controllers, secondary structure and mechanisms in the airframe (e.g., manual release mechanisms, slaved doors) as well as equipment that is located in the cockpi
19、t are not addressed in this ARP. 1.1 Purpose This document establishes minimum recommended design requirements and validation for landing gear structure and mechanisms. In addition, recommended guidelines regarding priorities in landing gear structural design particularly in the early design stages
20、is provided. 2. APPLICABLE DOCUMENTS The following publications form a part of this document to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other publications shall be the issue in effect on the date of the purchase order. In the event of co
21、nflict between the text of this document and references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 2.1 SAE Publications Available from SAE International, 400 Co
22、mmonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.AS1241 Fire Resistant Phosphate Ester Hydraulic Fluid for Aircraft AIR1494 Verification of Landing Gear Design Strength AIR1594 Plain Bearing Selection for Landing Gear A
23、pplications ARP1595 Aircraft Nosewheel Steering Systems AIR1752 Aircraft Nosewheel Steering/Centering Systems AS4052 Gland Design: Scraper, Landing Gear, Installation AIR4566 Crashworthy Landing Gear Design AS4716 Gland Design, O-ring and Other Elastomeric Seals AS4832 Gland Design: Nominal 3/8 in C
24、ross Section for Custom Compression Type Seals AIR4894 Landing Gear Stability ARP4912 Design Recommendations for Spare Seals in Landing Gear Shock Struts ARP4915 Disposition of Landing Gear Components Involved in Accidents/Incidents Copyright SAE International Provided by IHS under license with SAEN
25、ot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE ARP1311C - 4 -AS4941 Aerospace - General Requirements for Commercial Aircraft Hydraulic Components AIR5358 Landing Gear Shock Strut Hydraulic Fluid ARP5429 Landing Gear Fatigue Tests With Equivalent Damage Spectra
26、AIR5451 A Guide to Landing Gear System Integration AIR5479 Environmentally Compliant Processes for Landing Gear AIR5883 Landing Gears Shock Struts Bearing Selection ARP5935 Use of HVOF Thermal Spray Coatings for Hard Chrome Replacement in Landing Gear ApplicationsARP5936 Landing Gear Storage AS6053
27、Tests, Impact, Shock Absorber Landing Gear, Aircraft AS8860 Landing Gear Structural Requirements as Listed in the MIL-886X Series of Specifications AMS-P-83461 Packing, Preformed, Petroleum Hydraulic Fluid Resistant, Improved Performance at 275 F (135 C) AMS-QQ-N-290 Nickel Plating (Electrodeposited
28、) AMS-QQ-C-320 Chrome Plating (Electrodeposited) PT-37 Aircraft Landing Gear Systems PT-66 Emerging Technologies in Aircraft Landing Gear 2.2 U.S. Government Publications Available from the Document Automation and Production Service (DAPS), Building 4/D, 700 Robbins Avenue, Philadelphia, PA 19111-50
29、94, Tel: 215-697-6257, http:/assist.daps.dla.mil/quicksearch/.MIL-T-6053 Tests - Impact Shock Absorbers (Inactive) MIL-L-8552C Landing Gear, Aircraft Shockstrut (Gas/Oil Type) MIL-L-22589D Launching System - Nose Gear Type Aircraft MIL-T-81259B Tie Downs - Requirements for Airframe Designs MIL-A-886
30、0B Airplane Strength and Rigidity MIL-A-8862 Airplane Strength and Rigidity (Canceled) MIL-A-8863C Airplane Strength and Rigidity MIL-A-8867C Airplane Strength and Rigidity Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without
31、 license from IHS-,-,-SAE ARP1311C - 5 -MIL-PRF-5606H Hydraulic Fluid, Petroleum Base; Aircraft, Missile, and Ordnance MIL-PRF-87257B Hydraulic Fluid, Fire Resistant; Low Temperature, Synthetic Hydrocarbon Base, Aircraft and Missile MIL-PRF-83282D Hydraulic Fluid, Fire Resistant, Synthetic Hydrocarb
32、on Base, Metric, Nato Code Number H-537 NAS 1613 Seal Element, Packing, Preformed, Ethylene Propylene Rubber - Rev. 5; FSC 5330 MS 15000 Fittings - Lubrication - Hydraulic (Canceled) MS 15001 Fittings - Lubrication - Hydraulic (Canceled) MS 15002 Fittings - Lubrication - Hydraulic (Canceled) MS 1500
33、3 Fittings - Lubrication - Hydraulic (Canceled) MS 15004 Fittings - Lubrication - Hydraulic (Canceled) MS 28889 Valve, Air, High Pressure Charging (5000 psi) (Inactive) MS 33559 Adapter, Aircraft, Jacking Point, Design and Installation (Canceled) MS 33651 Boss, Air Connection, Design and Installatio
34、n (Inactive) MS 33675 Scraper Installation - Packing Gland Ring (Inactive) MIL-PRF-5503F Actuators: Aero Linear Utility, Hydraulic, General Spec For MIL-STD-805B Towing Fittings and Provisions for Military Aircraft MIL-STD-809 Adapter, Aircraft, Jacking Point, Design and Installation (Canceled) AR-M
35、MPDS-03 Metallic Materials Properties Development and Standardization JSSG 2006 DOD Joint Service Specification Guide - Aircraft Structures 2.3 ANSI Publications Available from American National Standards Institute, 25 West 43rd Street, New York, NY 10036-8002, Tel: 212-642-4900, www.ansi.org.ANSI B
36、46.1 2.4 FAA Publications Available from Federal Aviation Administration, 800 Independence Avenue, SW, Washington, DC 20591, Tel: 866-835-5322, www.faa.gov.FARs Part 23, 25, 27 and 29 AC 25.571-1C Damage Tolerance and Fatigue Evaluation of Structure AC 23-13A Copyright SAE International Provided by
37、IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE ARP1311C - 6 -2.5 EASA Publications Available from European Aviation Safety Agency, Postfach 10 12 53, D-50452 Koeln, Germany, Tel: +49-221-8999-000, www.easa.eu.int.CS-23, 25, 27 and 29
38、2.6 Other Publications Aircraft Landing Gear Design - Principles and Practices, by Norman S. Currey Landing Gear Design, by H. G. Conway Airplane Design Part IV Layout Design of Landing Gear and Systems, by Dr. Jan Roskam 3. DESIGN REQUIREMENTS The landing gear should fulfill all the regulatory and/
39、or any airframe manufacturers design requirements that are considered applicable to the aircraft being designed. 3.1 General Structural Requirements 3.1.1 Structural Capacity The landing gear should have adequate structural capacity for all combinations of loads that can be encountered during takeof
40、f, landing and ground handling conditions. The gear should be suitable to withstand all ground operational environments, including ambient temperature extremes and runway conditions.3.1.2 Structural Analysis An analytical assessment of the required structural capacity for all load carrying members,
41、using the design ground loads as specified by the airframe manufacturer, should precede the release of the landing gear design for manufacture. The analysis should include finite element analysis as appropriate for complex structural components. This structural capacity should include strength witho
42、ut permanent deformation, ultimate strength, stiffness, and structural stability. More detail requirements are described in the following paragraphs. 3.1.2.1 Design Loads Landing gear design loads for commercial aircraft are derived from requirements described in FAR/CS 25.471 through 25.519 or 23/2
43、7/29.471-511 as applicable. Design ground loads for military aircraft are governed by JSSG 2006 Aircraft Structures. Catapult, arrestment, and some ground handling or deck handling load conditions are unique to U.S. Navy applications. Those loads are treated as limit and ultimate in the same manner
44、as loads for land based aircraft. However, landing loads for U.S. Navy aircraft are derived from a multivariate analysis of input conditions to establish nearly worst case conditions. To prevent prohibitive weight and envelope penalties, the predicted landing loads are treated as design loads and no
45、t as limit/ultimate loads. The following are the load application locations for both static and fatigue conditions: - For all ground operation conditions, excluding nose landing gear (NLG) towing and jacking condition loads, the loads should be applied at the tire contact point. - For all landing co
46、nditions, drag and vertical loads should be applied at the axle and side loads applied at the tire contact point.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE ARP1311C - 7 - For all towing cond
47、itions involving a tow bar attachment to the NLG axle, drag and side loads for the NLG should be applied at the axle of the NLG and vertical loads should be applied at the tire contact point. Similar conditions apply to main landing gear (MLG) towing. The landing gear assembly should possess strengt
48、h to withstand all static dynamic, and fatigue loading conditions listed in the commercial regulations or military specifications in accordance with the criteria specified herein. The design should be based upon the most critical of the requirements. 3.1.2.2 Design Factors Design factors for bearing and/or joint sizing are used in the design of military landing gear, to provide added reliability and growth potential. All applicable loads are to be multiplied by these factors in the appropriate circumstance. Commercial landing gear typically do not use these factors with t
