1、MIL-A-8860B(AS)20 May 1987SUPERSEDINGMIL-A-8860(ASG)18 May 1960MILITARY SPECIFICATIONAIRPLANE STRENGTH AND RIGIDITYGENERAL SPECIFICATION FORThis specification is approved for use within the NavalAir Systems Command, Department of the Navy, and isavailable for use by all Departments and Agencies of t
2、heDepartment of Defense.1. SCOPE1.1 Scope. This specification contains general requirements, which, incombination with other applicable specifications, define the structuraldesign, analysis, test, and data requirements for fixed wing pilotedairplanes. These requirements include, but are not limited
3、to the following:a. The strength and rigidity of the structure of the airplaneincluding supporting and carry-through structures for fixedequipment and useful load items.b. The strength and rigidity of control systems for operation oflateral, longitudinal, and directional control surfaces; dive orspe
4、ed brakes; high lift devices; tabs; stabilizers; spoilers;certain other mechanisms; and their respective carry-throughstructures.c. The shock-absorption characteristics and strength of landing-gearunits and the strength and rigidity of their control systems and oftheir carry-through structures. Requ
5、irements for wheels, tires, andbrakes are also included.d. The strength of structures integral with the airplane provided fortransmitting catapulting forces to the airplanes, and for engagingshipboard and shorebase arresting gear, and barricades.AMSC N/A FSC 1510DISTRIBUTION STATEMENT A. Approved fo
6、r public release; distribution is unlimited.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-A-8860B(AS)e. The strength of anchor-line clamps, and the airplane strength forhoisting, jacking, towing, tie-down, and other ground- ordeck-handling cond
7、itions.f. Flutter and other aeroelastic instability prevention, andaeroacoustic and vibration characteristics.9“ Determination of special weapons effects.h. Structural design, analysis, and test data.i. Laboratory and flight tests performed to obtain informationregarding strength rigidity and loads.
8、j. Definitions.1.2 Modifications and amplification. This specification may be modifiedand amplified in contracts for piloted airplanes by type, detail, and designdata specifications, and addenda thereto.2. APPLICABLE DOCUMENTS2.1 Government documents.2.1.1 Specifications, standards, and handbooks. T
9、he following specif-ications, standards, and handbooks form a part of this specification to theextent specified herein. Unless otherwise specified, the issues of thesedocuments shall be those listed in the issue of the Department of DefenseIndex of Specifications and Standards (DODISS) and supplemen
10、t thereto, citedin the solicitation.SPECIFICATIONSFEDERALQQ-A-367MILITARYMIL-F-7190MIL-D-8708MIL-A-8861MIL-A-8863NIL-A-8865MIL-A-8866MIL-A-8867WL-A-8868Aluminum Alloy Forgings.Forgings, Steel, for Aircraft/Aerospace Equipment andSpecial Ordnance Applications.Demonstration Requirements for Airplanes.
11、Airplane Strength and Rigidity Flight Loads.Airplane Strength and Rigidity Ground Loads forNavy Procured Airplanes.Airplane Strength and Rigidity MiscellaneousLoads.Airplane Strength and Rigidity ReliabilityRequirements, Repeated Loads, and Fatigue.Airplane Strength and Rigidity Wound Tests.Airplane
12、 Strength and Rigidity Data and Reports.2Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-A-8860B(AS)SPECIFICATIONSMILITARY (cont)MIL-A-8869MIL-A-8870MIL-A-21180NIL-A-22771MIL=-T-81259MIL-F-83142STANDARDSMILITARYMIL-STD-210MIL-STD-1374MIL-STD-2175
13、HANDBOOKSMILITARYMIL-HDBK-5MIL-HDBK-17MIL-HDBK-23Airplane Strength and Rigidity Special WeaponsEffects.Airplane Strength and Rigidity, Vibration,Flutter, and Divergence.Aluminum Alloy Castings, High Strength.Aluminum Alloy Forgings, Heat Treated.Tie-downs, Airframe Design, Requirements for.Forging,
14、Titanium Alloys, for Aircraft and AerospaceApplications.Climatic Extremes for Military Equipment.Weight and Balance Data Reporting Forms for Aircraft.Castings, Classification and Inspection of.Aerospace Vehicle Structures, Metallic Materialsand Elements for.Plastic for Aerospace Vehicles part 1 Rein
15、forcedPlastics.Structural Sandwich Composites.2.1.2 Other Government documents (publications). TM following otherGovernment documents (Duplications) form a part of this specification to theextent specified herein. Unless otherwise specified, the issues shall bethose in effect on the date of the soli
16、citation.PUBLICATIONSNAVAL AIR SYSTEMS COMMANDSD-24 General Specification for Design and Construction ofAircraft Weapon Systems.(Copies of specifications, standards, handbooks, and other Governmentdocuments (publications) required by contractors in connection with specificacquisition functions shoul
17、d be obtained from the contracting activity or asdirected by the contracting officer.)3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-A-8860B(AS)2.1.3 Other publications. The following documents form a part of thisspecification to the extent sp
18、ecified herein. Unless otherwise specified, theissues of the documents which are DOD adopted shall be those listed in theissue of the DODISS specified in the solicitation. Unless otherwisespecified, the issues of documents not listed in the DODISS shall be the issueof the nongovernment documents whi
19、ch is current on the date of thesolicitation.AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI)ANSI Y 10.7 - Letter Symbols for Aeronautical Sciences.(Application for copies should be addressed to the American NationalStandards Institute, 1430 Broadway, New York, NY 10018.)(Nongovernment standards and oth
20、er publications are normally available fromthe organizations which prepare or which distribute the documents. Thesedocuments also may be available in or through libraries or other informationalservices.)2.2 Order of precedence. In the event of a conflict between the text ofthis specification and the
21、 references cited herein (except for associateddetail specifications, specification sheets or MS standards), the text of thisspecification shall take precedence. Nothing in this specification, however,shall supersede applicable laws and regulations unless a specific exemptionhas been obtained.3. REQ
22、UIREMENTS3.1 General. The requirements of this specification shall apply to fixed-wing piloted airplanes unless specific deviations therefrom are granted by thecontracting activity. These requirements are selected for general usage onthe basis of the particular type of airplane being designed and of
23、 theperformance of the basic, alternate, and training missions relative to thatdesign. The construction of the airplane shall conform to the manufacturingand process requirements of SD-24, as amended, to provide airplanes whichcomply with the design requirements of this specification, MIL-A-8861,MIL
24、-A-8863, MIL-A-8865, MIL-A-8866, MIL-A-8867, MIL-A-8868, MIL-A-8869, andMIL-A-8870.3.1.1 Terms. Terms, their definitions, nd symbols shall be in accordancewith 6.3.3.1.2 Limit loads. The load factors and load formulas noted in anyportion of this specification and the referenced specifications of sec
25、tion 2represent limit loads, unless otherwise specified.3.1.3 Ultimate loads. Except for loading conditions for which specificultimate loads are delineated, the ultimate loads are obtained by multiplyingthe limit loads by the ultimate factor of safety. Failure shall not occur atthe design ultimate l
26、oad. The ultimate factor of safety to be used for thedesign of the structure shall be 1.50, except that in certain cases for4Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-A-8860B(AS)considerations of added safety, rigidity, quality assurance, a
27、nd wear,additional strength or multiplying factors of safety are specified.3.1.4 Deformations. The cumulative effects of elastic, permanent, andthermal deformations which result from application of repeated loads, and fromapplication of design limit loads, shall not Interfere with the mechanicaloper
28、ation of the airplane, affect adversely its aero-dynamic characteristics,require repair, or require replacements of parts other than as specificallyapproved by the contracing activity. This requirement applies both toflight articles and to structural test articles when loaded statically ordynamicall
29、y, and when loaded in Increments of load or sinking speed asspecified for structural tests.3.1.4.1 Control Systems. All loads up to ultimate load for flight loadingconditions shall not cause binding or Interferences in the control systembetween the control surfaces and adjacent structures such as to
30、 inhibit safetyof flight operations.3.1.5 Load and temperature redistribution. If thermal, elastic andaeroelastic deformations of the structure occur as a result of limit flightand ground loading conditions, the external load and temperature distributionsshall include the effect of those deformation
31、s. Load redistributions andmagnitudes shall include those caused by thermally induced deformations,airload redistributions caused by surface temperature changes, rigiditychanges resulting from thermal stresses and other thermally induced effects,and aeroelastically induced deformations.3.1.6 Superim
32、posed loads. Residual loads remaining after extending orretracting landing gear and flaps, opening and closing bomb bay doors, orcaused by rigging loads of magnitudes specified by the contractor in theaircraft maintenance instructions, and preloads such as those occurring whensway-bracing is fitted,
33、 shall be combined with the loads resulting from thepertinent loading conditions. Loads acting upon the aircraft structure as aresult of the operation of armament and equipment, blasts, impingement ofegine exhaust, and full engine power shall be combined with the loads actingon the aircraft structur
34、e at rest on the ground and the loads acting on theaircraft structure during flight, except spins, for the basic and high dragconfigurations and during landings, as applicable.3.1.7 Transient response. The magnitudes and distributions of loads shallinclude the effects of the dynamic response of the
35、structure resulting fromthe transient or sudden application of loads such as: the dynamic responseresulting from aburpt maneuvers; detonation of special weapons; gusts;landings; taxiing braking wheels in air; sudden release of catapult holdbackforce; catapulting; response to catapult-tow forces; arr
36、esting; oscillationsof arresting gear deck pendants; slipping of arresting hooks on deck pendants;assisted-takeoff-unit loads; gun firing; release or ejection of stores; andparachute drop of cargo.5Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-
37、A-8860B(AS)3.1.8 Thermal considerations. The design of the airplane shall Includeprovision for the effects of: heating incidental to operation of powerplantsand other heat sources from within the airplane; operation in ambient atmospheres consistent with both the cold and hot atmosphere temperature-
38、versus-altitude relationship defined in MIL-STD-210 and extrapolated to coveroperational altitudes; aerodynamic heating; and heating encountered duringshipboard catapult launch operation, both forward and aft of the raised jetblast deflector (JBD) These effects shall include steady state and transie
39、ntexcursions of the airplane into and out of regimes of aerodynamic heatingconsistent with its anticipated employment. The design shall includeprovision for the cumulative effects of the time-temperature-load history ofthe airplane for its planned service life.3.1.9 Authorized changes. Government-re
40、sponsible changes, authorizedsubsequent to the establishment of the original contract requirements, shallnot increase or decrease the appropriate structural design gross weightsunless specifically stated by the change. Strength is required in the changedairplane for all loads, load factors, accelera
41、tions, and loading conditionswhich result from application of the structural design requirements of thedetail specification to the changed airplane at the specified structuraldesign gross weights.3.1.10 Fall-safe. The complete airframe shall be designed such thatfailure of a single structural elemen
42、t will neither cause catastrophic failureof the airplane nor prevent safe continuance of its flight to a planneddestination or to an aircraft carrier. Redundancy, alternate load paths andsystems, and other fail-safe principles are required to achieve thiscapability. For this fall-safe requirement, t
43、he airframe is defined asincluding all of the structural elements of major systems and all of thestructural connecting and supporting elements of powerplant installations,whereby the failure of these elements can cause uncontrollable motions of theairplane within the speed limits for its structural
44、design, prevent theairplane from achieving speeds sufficiently low to effect a safe landing, andreduce the ultimate factor of safety for flight design conditions from 1.5 toa value less than 1.0.3.1.11 External store stations. Strength shall be provided at each storestation for all flight conditions
45、, including all flight attitudes andmiscellaneous occurrences (e.g., engine stalls), and all ground loadingconditions for all possible combinations of stores specified in the detailspecification. The loads imposed by the airplane response to the dynamicloads at each store station shall not create an
46、 exceedence of the strengthlimit of contractor furnished stores or suspension equipment.3.2 Design strength For all design conditions, strength shall beprovided so that material yield allowable stresses will not be exceeded atlimit loads and material ultimate allowable stresses will not be exceeded
47、atultimate loads. For repeated-load and fatigue conditions, strength shall beprovided so that the fatigue life of the structure will equal or exceed thespecified life, including specified scatter factors. The continuity of the6Provided by IHSNot for ResaleNo reproduction or networking permitted with
48、out license from IHS-,-,-MIL-A-8860B(AS)structural design of the attachments of movable aerodynamic surfaces shall besuch that initial failures of the complete Installations, under static and/orrepeated loads, will be major failures of the movable or fixed surfaces, notfailures of the attachment.3.2
49、.1 Design data and allowable materials properties. Design data andproperties of materials shall be obtained from MIL-HDBK-5 and MIL-HDBK-23, orfrom other sources subject to acceptance by the contracting activity. SD-24contains requirements on fibrous composites which shall be used in lieu ofMIL-HDBK-17, and contains additional requirements for the use of high strengthsteels. Allowable properties based on static and fatigue test data other thanhandbook data may be used
