1、MIL-T-l8847C(AS) 14 October 1986 SUPERSEDING 10 June 1976 MIL-T-l8847B(AS) MILITARY SPECIFICATION TANKS, FUEL, AIRCRAFT, AUXILIARY EXTERNAL, DESIGN AND INSTALLATION OF This specification is approved for use within the Naval Air Systems Command, Department of the Navy, and is available for use by all
2、 Departments and Agencies of the Department of Defense. l. SCOPE 1.1 Scope. This specification covers requirements for the design, test, and installation of auxiliary external aircraft fuel tanks. 1.2 Classification. Auxiliary external aircraft fuel tanks covered by this specification shall be of th
3、e following types: Type I - Non-survivable fuel tank Type II - Survivable fuel tank 2. APPLICABLE DOCUMENTS 2.1 Government documents. 2.1.1 Specifications and standards. The following specifications and standards form a part of this specification to the extent specified herein. Unless otherwise spec
4、ified, the issues of these documents shall be those listed in the issue of the Department of Defense Index of Specifications and Standards (DODISS) and supplement thereto, cited in the sol ici tation. SPECIFICATIONS FEDERAL TT-S-735 Standard Test F1 uids, Hydrocarbon MMM-A- 1 32 Adhesives, Heat Resi
5、stant, Airframe Structural, Metal to Metal PPP-B-636 Boxes, Shipping, Fiberboard Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Naval Air Engineering Center, Systems Engineering and Standardiza
6、tion Department (Code 93), Lakehurst, NJ 08733-5100, by using the self-addressed Standardization Document Improvement.Proposa1 (DD Form 1426) appearing at th end of this document or by letter. / A c AMSC NIA THIS DOCUMENT CONTAINS 4 I PAGES. FSC 1560 DISTRIBUTION STATEMENT A. Approved for pub1 ic re
7、lease; distribution is un1 imi ted, Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MILITARY MIL-P-11 6 DOD-D-1 000 MIL-B-5087 MIL-C-5501 MIL-T-5624 MIL-T-6396 MIL-C-6529 MIL-W-6858 MIL-F-7179 MIL-S-7742 MI L-D-85 1 2 MIL-A-8591 MIL-W-8604 MIL-F-861
8、5 MI L-0-8708 MIL-F-8785 MIL-A-8868 MIL-S-8879 MIL-C-9084 MIL-R-9299 MI L-F-1 7874 MIL-1-1 8802 MIL-R-21 931 MIL-G38373 MI L-P-38477 MI L-C-52950 MI L-R-60346 MIL-V-81 356 MIL-C-81986 STANDARDS FEDERAL FED-STD-141 MIL-T-1 8847C(AS) Preservation, Methods of Drawings, Engineerlng and Associated List B
9、onding, Electrical, and Lightning Protection, for Aerospace Sys tems Cap and Plug, Protective, Dust and Moisture Seal Turbine Fuel , Aviation, Grades JP-4 and JP-5 Tanks, Aircraft, Propulsion Fluid System, Removable, Non-sel f-seal i ng Corrosion Preventative, Aircraft Engine We1 ding Resi stance, S
10、pot and Seam Finishes, Coatings, and Sealants for the Protection of Aerospace Weapon Systems Screw Threads, Standard, Optimum Selected Series, General Specif i cation for Support Equipment , Aeronaut! cal, Special , General Specification for the Design of: Airborne Stores, Suspension Equipment, and
11、Aircraft Store Interface (Carriage Phase), General Design Cri terla for Welding, Fusion, Aluminum Alloys, Process and Performance of Fuel System Components, General Specification for Demonstratlon Requirements for Airplanes Flying Qualities of Piloted Airplanes Airplane Strength and Rigldi ty Data a
12、nd Reports Screw Threads, Control led Radius Root with Increased Minor Diameter, General Specification for Cloth, Glass, Finished, for Resin Laminates Resin, Phenolic, Laminating Fuel Systems, Aircraft, Installation and Test of Installation of Fuel and Oil Lines, Aircraft Resin, Epoxy Cap, Fluid Tan
13、k Filler Plastic Material, Pressure Sensitive Adhesive for Aerospace Identification and Marking Crates, Wood, Open and Covered Rvi ng, Glass, Fi brous (for Prepreg Tape and Roving, Filament Winding, and Pultrusion Applications) Valve, Fuel System Pressurization and Vent Core Material, Plastic Honeyc
14、omb, Nylon Paper Base, For Aircraft Structural Applications Paint, Varnish, Lacquer, and Related Materials; Methods for Sampling and Testing Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MI LI TARY MIL-STD-105 MI L-STD- 1 2 9 MIL-STD-130 MI L-STD-1
15、43 MI L-STD-453 MIL-STD-462 MIL-STD-810 MIL-STD-889 Sampling Procedures and Tables for Inspection by Attributes Marking for Shipment and Storage Identification Marking of U.S. Military Property Standards and Specif i cations , Order of Precedence for the Selection of Inspection, Radiographic Electro
16、magnetic Interference Characteristics, Measurement of Environmental Test Methods and Engineering Guidelines Dissimilar Metals MIL-STD-1515 Fastener Systems for Aerospace Applications MIL-STD-1523 Age Controls of Age Sensitive Elastomeric Materiel (for MIL-STD-1595 Qualification of Aircraft, Missile
17、and Aerospace Fusion MIL-STD-6866 Inspection, Liquid Penetrant MS2957 1 Valve, Fuel Drain, Self-Locking, Flush Type MS33540 Safety Wiring and Cotter Pinning, General Practice for Aerospace Applications) We1 ders 2.1.2 Other Government documents, drawings, and publications. The following other Govern
18、ment documents form a part of this specification to the extent specified herein. Unless otherwise specified, the issues shall be those in effect on the date of the solicitation. NAVAL AIR SYSTEMS COMMAND SD-24 Vol. I General Specification for Design and Construction of and Vol . II Aircraft Weapons,
19、Systems MIL-BULL-147 Specifications and Standards of Non-government Organizations Released for Flight Vehicle Construction MI L-BULL-544 List of FederallMilitarylIndustry Specifications and Standards and NAVAIR Series Documents Approved by the Naval Air Systems Command (Copies of specifications, sta
20、ndards, handbooks , drawings, pub1 i cations and other Government documents required by contractors in connection with specific acquisttion functions should be obtained from the contracting activity or as directed by the contracting activity.) 2.2 Other publications. The following documents form a p
21、art of this specificatlon to the extent specified herein. Unless otherwise specified, the issues of the documents which are DOD adopted shall be those 1 isted in the issue of the DODISS specified in the solicitation. Unless otherwise . specified, the issues of documents not listed in the DODISS shal
22、l be the issue of the nongovernment documents which is current on the date of the solicitation. 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-T-l8847C(AS) AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) ASTM-F22 Hydrophobic Surface Films by
23、 the Water-Break Test, Test Method for *ASTM-D1002 Strength Properties of Adhesives in Shear by Tension Loading (Metal-to-Metal), Test Method for *ASTM-D2583 Indentation Hardness of Rigid Plastics by Means of a Barco1 Impressor, Test Method for *ASTM-D3951 Commercial Packaging, Practice for *DOD Ado
24、pted 6 (Application for copies should be addressed to the American Society for Testing and Materials, 1916 Race Street, Philadelphia, PA 19103.) ASO-Ml 0357 ICU Polyisocyanurate Foam (Avco Systems Division) (Application for copies should be addressed to the AVCO Systems Division, 201 Lowell Street,
25、Wilmington, MA 01887.1 2.3 Order of precedence. In the event of a conflict between the text of this specification and the references cited herein (except for associated detail specifications, specification sheets or MS standards), the text of this specification shall take precedence. Nothing in this
26、 specification, however, shall supersede applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 Selection of specifications and standards. Specifi,cations and standards for necessary commodities and services not specified herein shall be selected in accord
27、ance-wi th MIL-STO-143, MIL-BULL-147,. and MIL-BULL-544. 3.2 Type I and Type II tanks. Unless otherwise specified, the following paragraphs pertain to both Type I (non-survivable) and Type II (survivable) externaT fuel tanks. 3.3 First article. When specified in the contract or purchase order, a sam
28、ple shall be subjected to first article inspection (see 4.3.1 and 6.3). 3.4 Materials. Materials shall conform to applicable specifications and shall be as specified herein. Materials which are not covered by applicable specifications, or which are not specifically described herein, shall be of the
29、best quality, of the lightest practical weight, and suitable for the purpose intended. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3.4.1 Metals. Metals used in this tank or its components shall be of the corrosion-resisting type or suitably tre
30、ated to resist corrosion in fuels, salt spray, or atmospheric conditions during the service life of the tank when in storage or in normal service use. 3.4.1.1 Dissimilar metals. Dissimilar metals as defined in MIL-STD-889 shall not be used in intimate contact with each other unless suitably protecte
31、d against electrolytic corrosion. 3.5 General characteristics. 3.5.1 Design. External auxi 1 iary fuel tanks shall be designed to carry fuel satisfactorily, without any leakage, under the condltions of installation, vibration, temperature, pressure, and loadings (including accelerations of flight ma
32、neuvers, catapult take-off, and arrested landings) peculiar to the applicable aircraft. The fuel and air systems shall be designed to function satisfactorily under the foregoing conditions. All tanks shall be so designed that they shall be readily removable or jettisonable from the aircraft. Suspens
33、ion provisions shall comply with the requirements of MIL-A-8591. 3.5.1.1 Design analysis. The contractor shall provide a design stress analysi S report of the tank in accordance with MIL-A-8868, sixty days prior to initiation of the first article tests. One copy of the report shall be forwarded to t
34、he Commander# Naval Air Systems Command (AIR-53031), Washington, DC 20361-5300, for approval, and one copy to the Commander, Naval Air Development Center (Code 60131, Warminster, PA 18974-5000, for information. 3.5.1.2 Drawings. Drawings and associated lists shall be prepared in accordance with DOD-
35、D-1000 Level III. Drawing submittal shall be in accordance with the data requirements of the contract. 3.5.1.3 Capacity. The usable capacity of the tank shall be not less than specified nor more than 110 percent of that specified. Sufficient gross capacity shall be provided to allow for expanslon of
36、 fuel, but the gross capacity shall be not more than 115 percent of the specified capacity. 3.5.1.3.1 Usable fuel. The usable fuel shall be in accordance with the tank gallon size specified in the contract. 3.5.1.3.2 Unusable fuel. The tank shall have a maximum of 1 percent unusable fuel of the tota
37、l usable fuel. 3.5.1.3.3 Undrainable fuel. The tank shall have a maximum of one pint of undrai nab1 e fuel . 3.5.1.3.4 Expansion space. The tank shall have an expansion space equivalent to 5 percent of the total usable fuel. 3.5.1.4 Weight. The completely assembled empty tank weight shall be designe
38、d to create the lightest weight tank. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3.5.1.4.1 Tank center of gravity. The center of gravity location and travel with varying quanti ties of fuel within the tank shall be such that there shall be no
39、adverse effects on the aircraft structure or aerodynamjc characteristlcs that depend on center of gravity location at al 1 atti tudes of the aircraft that re otherwise al lowable. 3.5.1.5 Fuel tank design loads. 3.5.1.5.1 Rotary wing crashworthiness application. The tank must be able tand survivable
40、 or margi na1 ly survivable crash areas (see Figure 1) leakage. The tank shall be in any fuel condition from empty to full. to wlths without 3.5.1 for the a b ion 5.2 Strength. Strength shall be provided in the tank and suspens oads in accordance W th MIL-A-8591 at the fol lowing weights: Flight con
41、ditions: tank 3/4 full and tank empty Catapulting conditions: tank full c. Landlng conditions: tank 1/4 full The critical combination to be used for design shall be selected by the contractor and approved by the Naval Ai r Systems Command. 3.5.1.5.3 Tank ejection load. The tank shall be capable of w
42、ithstanding the ejection loads without rupture in accordance with MIL-A-8591. 3,5.1 5.4 Cradl i ng and hand1 i ng areas. As a minimum, al 1 tanks shall have cradling and handling areas capable of withstanding loads equal to three times the weight of the tank without permanent deformation. 3.5.1.6 Su
43、spension. Tanks shall be provided with means of suspending the tank from the applicable aircraft. The location of the suspension system shall be in accordance with MIL-A-8591. The suspension lugs shall be removable. 3.5. l. 6.1 Sway brace a= The bomb rack sway brace pad areas shall be provided In ac
44、cordance with MIL-A-8591. 3.5.1.7 Ejection area. The ejection area shall conform to the requirements Of MIL-A-8591 3.5.1.8 Pressures. The tank shall. withstand the following pressures. 3.5.1.8.1 Internal pressure. The internal pressure loads are as follows: Operating: 15 psig Proof: 75 psig Burst: 1
45、12 psig 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-0- m 4 m O Fi O * 4 O m I- O (u Fi O 4 6-l O O Fi O co O h O m O m O * O Cr) O N + a C MIL-T-l8847C(AS) O Fi O N O m O d O v) O Io O h SdJ - A113013A lV311ll3A 7 . Provided by IHSNot for Resal
46、eNo reproduction or networking permitted without license from IHS-,-,-MIL-T-1 8847C(AS) 3.5.1 8.2 External (vacuum) pressure. The external vacuum pressure loads are as fol lows : Operat i ng : O psig Proof: 10 psig negative Burst: 12 psig negative 3.5.1.9 Fuel transfer system. The fuel transfer syst
47、em shall be designed in accordance wf th MIL-F-17874 and al low for both ground and in-f 1 ight fuel i ng and defueling of the fuel tank. The fuel tank fuel lines and connections and installation shall be in accordance with MIL-F-8615. Provisions shall be incorporated to prevent fuel spillage from t
48、he fuel and air connectors during jettison or disengagement from the aircraft, 3.5.1.9.1 pressure reliefivent valve. Unless otherwise specified, the tank shall be equipped w9 th a pressure re1 lefivent valve that conforms to MIL-V-81 356. If i t i s not practi cal to uti 1 i te a val ve conformi ng
49、to MIL-V-81356, the tank shall be equipped with a pressure relief valve. The valve shall be designed to remain closed when the pressure differential between the tank and ambient atmospheric pressure Is less than 2 “0.5 psi above normal, and to open and relieve the excess fuel pressure when the differential is greater than 2 “0.5 psi above normal. The pressure relief valve shall incorporate a means to prevent leakage of fuel during c
