1、 MIL-DTL-27422E 4 April 12 SUPERSEDING MIL-DTL-27422D 30 January 2007 DETAIL SPECIFICATION FOR THE TANK, FUEL, CRASH-RESISTANT, BALLISTIC-TOLERANT, AIRCRAFT This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification cov
2、ers the requirements and verification testing for crash-resistant, ballistic-tolerant fuel cells for use in fixed wing and rotary-wing aircraft (including tilt rotor). Exact design criteria such as fuel cell dimensions, total weight, and interface requirements will be dependent upon the intended air
3、craft specified in the contract or purchase order. 1.2 Classification. Crash-resistant, ballistic-tolerant, fuel cells will be of the following types and classes: 1.2.1 Class. (see 6.1) Class A - Flexible fuel cell construction Class B - Semi-rigid or self-supporting fuel cell construction 1.2.2 Typ
4、e. (see 6.1) Type I - Self-sealing or partially self-sealing Type II - Non-self-sealing AMSC N/A FSC 1560 INCH-POUND Comments, suggestions, or questions on this document should be addressed to Commander, US Army Aviation and Missile Command, ATTN: RDMR-SET-ST, Redstone Arsenal, AL 35898-5000, or ema
5、iled to malinda.allcorn1us.army.mil. Since contact information may change, you may want to verify the currency of this address information using the ASSIST Online database at https:/assist.daps.dla.mil/. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-
6、,-MIL-DTL-27422E 2 1.2.3 Protection level. (see 6.1) Level A - Fuel cell is completely self-sealing against .50 caliber and 20 mm (entry wound only for 20 mm). Level B - Part of the fuel cell is non-self-sealing and part is self-sealing against .50 caliber and 20 mm (entry wound only for 20 mm). Lev
7、el C - Part of the fuel cell is self-sealing against .50 caliber and part of the cell is self-sealing against 14.5 mm. Level D - Fuel cell is completely self-sealing against 14.5 mm and 20 mm (entry wound only for 20 mm). Level E - Part of the fuel cell is self-sealing against 14.5 mm and 20 mm (ent
8、ry wound only for 20 mm) and part of the fuel cell is non-self-sealing. 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3 and 4 of this specification. This section does not include documents cited in other sections of this specification or recommen
9、ded for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements documents cited in sections 3 and 4 of this specification, whether or not they are listed in this secti
10、on. 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those listed in the issue of the Department
11、of Defense Index of Specifications and Standards (DoDISS) and supplement thereto, cited in the solicitation (see 6.2(b). FEDERAL STANDARDS FED-STD-601 Federal Standard, Testing Method Standard, Rubber: Sampling and Testing FED-STD-791 Federal Standard, Testing Method of Lubricants, Liquid Fuels, and
12、 Related Products DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-DTL-5624 Detail Specification, Turbine Fuel, Aviation, Grades JP-4, JP-5 and JP5/JP-8 ST MIL-DTL-83133 Detail Specification, Turbine Fuel, Aviation, Grades JP-8 NATO F-34), NATO F-35, and JP-8+100 (NATO F-37) Provided by IHSNot for ResaleNo
13、reproduction or networking permitted without license from IHS-,-,-MIL-DTL-27422E 3 DEPARTMENT OF DEFENSE STANDARDS MIL-STD-129 Department of Defense Standard Practice, Military Marking for Shipment and Storage MIL-STD-130 Department of Defense Standard Practice, Identification Marking of US Military
14、 property MIL-STD-662 Department of Defense Test Method Standard, V50 Ballistic Test for Armor MIL-STD-801 Department of Defense Test Method Standard, Inspection and Acceptance Standards for Fuel Cells and Fittings (Copies of these documents are available from the Standardization Document Order Desk
15、, 700 Robbins Avenue, Building 4D, Philadelphia PA 19111-5094 or online at https:/assist.daps.dla.mil or https:/assist.daps.dla.mil/quicksearch.) 2.2.2 Non-government publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the is
16、sues of the documents which are DoD adopted are those listed in the issue of the DoDISS cited in the solicitation. Unless otherwise specified herein, the issues of documents not listed in the DoDISS are the issues of the documents cited in the solicitation (see 6.2). ASTM INTERNATIONAL ASTM D381 Sta
17、ndard Test Method for Gum Content in Fuels by Jet Evaporation ASTM D413 Standard Test Methods for Rubber Property Adhesion to Flexible Substrate ASTM D471 Standard Test Method for Ref. B Rubber Property Effect of Liquids ASTM D910 Standard Specification for Aviation Gasolines ASTM D5034 Standard Tes
18、t Method for Breaking Strength and Elongation of Textile Fabrics (Grab Test) (Copies of these documents are available at ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken PA 19428-2959. Electronic copies of ASTM standards may be obtained at http:/www.astm.org.) SOCIETY OF AUT
19、OMOTIVE ENGINEERS (SAE) INTERNATIONAL SAE AS 8879 Screw Threads UNJ Profile, Inch Controlled Radius Root With Increased Minor Diameter (Copies of these documents are available from Society of Automotive Engineers, Inc., 400 Commonwealth Drive, Warrendale, PA 15096-0001 or online at http:/www.sae.org
20、.) Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-27422E 4 2.4 Order of precedence. In the event of a conflict between the text of this document and the references cited herein, the text of this document takes precedence. Nothing in this doc
21、ument, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 Application. The requirements of this specification apply only to fuel cells that are to be installed within or on the aircraft (i.e. internal or external fuel cells), or as
22、specified by the Procuring Activity. A tank is defined as a single fuel cell or group of fuel cells interconnected, and the components attached thereto. 3.2 Materials. Materials conforming to contractor (see 6.4.a) or manufacturer (see 6.4.g) specifications may be used provided those specifications
23、contain provisions for verification tests. However, the use of magnesium is prohibited and cadmium-plated parts shall not be used when those parts will be exposed to fuel. 3.3 Design criteria. 3.3.1 Classification requirements. The fuel cell shall be designed for the class, type, and protection leve
24、l described below in order to meet the applicable aircraft requirements as stated in the contract or purchase order: 3.3.1.1 Class. (see 4.5.6.4) 3.3.1.1.1 Class A. The Class A fuel cell shall have flexible construction. 3.3.1.1.2 Class B. The Class B fuel cell shall have semi-rigid or self-supporti
25、ng fuel cell construction. 3.3.1.2 Type. (see 4.5.6.4) 3.3.1.2.1 Type I. A Type I fuel cell shall be self-sealing or partially self-sealing. The portions of the fuel cells to be self-sealing and non-self-sealing shall be as specified by the Procuring Activity based on overall aircraft survivability
26、requirements. The non-self-sealing portions (if any) shall conform to the requirements for Type II fuel cells. 3.3.1.2.2 Type II. A Type II fuel cell shall be non-self-sealing. 3.3.1.3 Protection level. (see 4.5.6.4) 3.3.1.3.1 Level A. The fuel cell designed for Level A protection shall be completel
27、y self-sealing against .50 caliber and 20 mm (entry wound only for 20 mm). 3.3.1.3.2 Level B. Part of the fuel cell designed for Level B protection shall be non-self sealing and part of the fuel cell shall be self-sealing against .50 caliber and 20 mm (entry wound only for 20 mm). The portions of th
28、e fuel cells to be self-sealing and non-self-sealing shall be as specified by the Procuring Activity based on overall aircraft survivability requirements. The non-self-sealing portions shall conform to the requirements for Type II fuel cells. 3.3.1.3.3 Level C. Part of the fuel cell designed for Lev
29、el C protection shall be self-sealing Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-27422E 5 against .50 caliber and part of the fuel cell shall be self-sealing against 14.5 mm. The portions of the fuel cell to be protected against .50 cali
30、ber and 14.5 mm shall be as specified by the Procuring Activity based on overall aircraft survivability requirements. 3.3.1.3.4 Level D. The fuel cell designed for Level D protection shall be completely self-sealing against 14.5 mm and 20 mm (entry wound only for 20 mm). 3.3.1.3.5 Level E. Part of t
31、he fuel cell designed for Level E protection shall be self-sealing against 14.5 mm and 20 mm (entry wound only for 20 mm) and part of the cell shall be non self-sealing. The portions of the fuel cells to be self-sealing and non-self-sealing shall be as specified by the Procuring Activity based on ov
32、erall aircraft survivability requirements. The non-self-sealing portions shall conform to the requirements for Type II fuel cells. 3.3.2 Dimensions. (see 4.6.2.1.2) 3.3.2.1 Class A fuel cell dimensions. All outside dimensions of a Class A fuel cell (including attachment points) shall be sized to acc
33、ommodate the corresponding dimensions of the fuel cell host cavity given in the applicable aircraft documentation specified by the contract or purchase order. The amount of oversize between attachment points and between any attachment point and the nearest edge shall not exceed 0.250 inch. The fuel
34、cells shall be designed so that they can be installed by hand, without the need of forcing tools. Additionally, the fuel cells shall be designed so that there shall be no evidence of wrinkles caused by stress following installation of the fuel cell. 3.3.2.2 Class B fuel cell dimensions. All outside
35、dimensions of the Class B fuel cell (including attachment points) shall be sized to accommodate the corresponding dimensions of the fuel cell host cavity given in the applicable aircraft documentation specified by the contract or purchase order. 3.3.3 Capacity. (see 4.3.3.2) 3.3.3.1 Class A fuel cel
36、l capacity. The capacity of the Class A fuel cell shall be as stated in the applicable aircraft documentation specified by the contract or purchase order. 3.3.3.2 Class B fuel cell capacity. The capacity of the Class B fuel cell shall be according to the applicable aircraft documentation specified b
37、y the contract or purchase order. However, the fuel level versus volume curve on production cells shall be within 1.5 percent to the average fuel level versus volume curve. 3.4 Construction. 3.4.1 Inner ply layer. For Type I fuel cells the inner ply layer and barrier shall prevent sealant activation
38、. For either Type I or Type II fuel cells the diffusion rate of fuel shall be no greater than 0.025 fluid ounces per square foot within a 24-hour period. (see 4.4.5.2) 3.4.2 Fabric ply. The edges of material in the lap seams of any ply in a fuel cell shall not be superimposed on parallel seams of an
39、 adjacent ply. (see 4.4.5.3 and 4.4.5.4) 3.4.3 Sealant. The Type I fuel cell shall include a sealant to ensure the fuel cell meets the requirements of 3.3.1.1.1 and 3.3.1.1.2 for either Class A or B, as specified in the contract or purchase order. (see 4.5.6.4) Provided by IHSNot for ResaleNo reprod
40、uction or networking permitted without license from IHS-,-,-MIL-DTL-27422E 6 3.4.4 Fittings. Fuel cell fittings shall not leak. Additionally, fittings for fuel cells shall conform to the design guidance and requirements in this specification, unless otherwise specified in the applicable aircraft doc
41、umentation cited in the contract or purchase order. Single plane fittings shall be used wherever practicable. The use of through-bolts is prohibited where a bolt head seal is required. (see 4.7.1) 3.4.5 Screw thread. SAE AS8879 may be used as guidance relative to screw thread requirements. The use o
42、f pipe threads is prohibited. (see 4.6.2.1.1) 3.5 Performance. 3.5.1 Fuel types. Fuel cells designed using this specification shall be compatible with all commercial and military type fuels. Primary military fuels are those meeting the requirements of ASTM-D910, MIL-DTL-5624 and MIL-DTL-83133. (see
43、4.3.3) 3.5.2 Fuel cell strength. The fuel cell, when installed in the aircraft for which it is designed, shall withstand: (see 4.4.3 and 4.4.4) a. Flexing resulting from vibration caused by the aircraft b. Impact loads incident to takeoff, taxiing, and landing (including catapulting and arresting) d
44、. Hydraulic surge of fuel incident to gunfire as specified in 3.3.1.3 e. Pressure loads resulting from hydrostatic head of fuel during level flight or maneuvers, and resulting from neutral gases used to pressurize fuel tanks f. Crash loads as specified in the applicable aircraft documentation. (see
45、4.7.18 and 4.7.18.1) 3.5.3 Leaking and tearing following gunfire. 3.5.3.1 Type I fuel cell. (see 4.5.7.1 and 4.5.7.2) 3.5.3.1.1 Leaking. 3.5.3.1.1.1 Ambient temperature. A Type I fuel cell shall dry or damp seal (6.4(d) and 6.4(c) within 2 minutes in ambient temperature (Phases I and II). 3.5.3.1.1.
46、2 Low temperature. A Type I fuel cell shall dry or damp seal (see 6.4(d) and 6.4(c) within 4 minutes or less following gunfire in temperatures as low as -40 F (Phase I only). The Procuring Activity may waive this requirement when fuel cell temperatures will not be subject to cold temperature gunfire
47、 in operation (i.e. in cases where hot fuel is recirculated into fuel cells). 3.5.3.1.2 Tearing. A Type I fuel cell shall withstand gunfire without tearing in ambient temperatures and only sustain cracking of the inner liner when gunfire is encountered in low temperatures. 3.5.3.2 Type II fuel cell.
48、 A Type II fuel cell tear shall be: a. Not larger than 4 inches measured radially from the edge of the wound at each entry and exit Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-27422E 7 point, in low temperatures, or b. Not larger than 3 i
49、nches measured radially from the edge of the wound at each entry and exit point in ambient temperatures. c. One that radiates from the bullet hole as a direct result of shrapnel or structure damage. 3.5.4 Operating temperature. Types I and II fuel cells shall operate throughout an ambient temperature range of -65 to +160 F and fuel temperature range of -65 to +135 F.
