1、- MIL-U-6729C m 0b 38115234 TT2 = I INCH-POUND I MIL-W-6729C 08 March 1993 SUPERSEDING MIL-W-O067298(AS MIL-W-6729A 28 April 1983 10 September 1962 MILITARY SPECIFICATION WATERTIGHTNESS OF AIRCRAFT, GENERAL SPECIFICATION FOR This specification is approved for use by all Departments and Agencies of t
2、he Department of Defense. 1. SCOPE 1.1 Scope. This specification covers testing for watertightness and water control of aircraft for rainy weather and aircraft washing. 2. APPLICABLE DOCUMENTS 2.1 Government documents. The following Government documents and publications form a part of this document
3、to the extent specified herein. specified, the issues are those cited in the solicitation. Unless otherwise NAVY PUBLICATIONS SO-24 General Specification for Design and Construction of Aircraft Weapon Systems. Volume I Volume II - Rotary Wing Aircraft - Fixed Wing Aircraft NAVAIR 01-1A-509 Aircraft
4、Weapons Systems Cleaning and Corrosion Control (Copies of SO-24 General Specification are available from the Defense Copies of NAVAIR 01-1A-509 are available from the Aviation Supply Office, Printing Service, Bldg 4D, 700 Robbins Avenue, Philadelphia, PA 19111-5094. 5801 Tabor Road, Philadelphia, PA
5、 19120.) Beneficial comments, (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Commanding Officer, Naval Air Warfare Center Aircraft Divi sion Lakehurst, Systems Requirements Department, Code SR3, Lakehurst, NJ 0873
6、3-5100, by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter. AMSC NJA FSC 15GP DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Provided by IHSNot for ResaleNo reproduction or net
7、working permitted without license from IHS-,-,-VIL-W-6729C 999990b 1845235 939 MIL-W-6729C * 2.2 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 document, however, supersede
8、s applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS * 3.1 Desiqn and construction. Aircraft shall be designed and constructed in accordance with watertightness (see 6.4.3) requirements spec fied in SD-24 for Navy aircraft or the contract. procedures and f
9、or all aircraft environmental conditions in towed or flight configurations including rain, wind, humidity, driven rain, salt spray and mist. These requirements are applicable for aircraft cleaning * 3.1.1 Watertight areas. Areas containing equipment that may experience adverse effects from water int
10、rusion (see 6.4.2) including corrosion, electrical discontinuity, or any other hazard related to aircraft safety or mission capability shall be designated watertight. The design of the aircraft shall ensure that these areas remain free from external water intrusion, migration of water from other are
11、as and condensation. * 3.1.2 Non-watertight areas. Areas where the presence of water will not adversely affect equipment performance shall be designated non-watertight. aircraft should be such that any water that enters non-watertight sections immediately flow to the aircraft exterior or designated
12、drainage area. * 4. QUALITY ASSURANCE PROVISIONS The design of the 4.1 Responsibility for inspection. Unless otherwise specified in the contract or purchase order, the contractor is responsible for the performance of all inspection requirements (examinations and tests) as specified herein. specified
13、 in the contract or purchase order, the contractor may use his own or any other facilities suitable for the performance of the inspection requirements specified herein, unless disapproved by the Government. right to perform any of the inspections set forth in this specification where such inspection
14、s are deemed necessary to ensure supplies and services conform to prescribed requirements. Except as otherwise The Government reserves the * 4.1.1 Responsibility for compliance. All items shall meet the requirements of section 3. contractors overall inspection system or qual i ty program. inspection
15、 requirements in the specification shall not re1 ieve the contractor of the responsi bi 1 i ty of ensuring that al 1 products or suppl ies submi tted to the Government for acceptance comply with all requirements of the contract. part of manufacturing operations, is an acceptable practice to ascertai
16、n conformance to requirements, however, this does not authorize submission of known defective material, either indicated or actual, nor does it commit the Government to accept defective material. The inspection set forth in this specification shall become a part of the The absence of any Sampling in
17、spection, as * 4.2 Classification of inspections. The inspection requirements specified herein are classified as quality conformance inspections (see 4.4). 4.3 Inspection conditions. Unless otherwise specified, al 1 inspections shall be performed in accordance with the test conditions in 4.5 and Tab
18、le I. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIt-W-b72C 9Ob 1845236 75 MIL-W-6729C 4.4 Qual i ty conformance inspections. Qual i ty conformance inspections shall include the tests of 4.6 and inspections of 4.7. TABLE 1. Watertightness samp
19、ling plan. Pur pos e of test Design acceptance Qual i ty conform- ance acceptance Type of test Ground (see 4.6.1) Flight (see 4.6.3) Cleaning (see 4.6.4) Ground (see 4.6.1) Samp 1 i ng Last full scale development I;FSO) aircraft Same as above Third aircraft of each lot after FSD Second, fi f th, ten
20、th and every tenth aircraft thereafter in each production lot Remarks If less than 3 FSD aircraft procured, teslt second pilot production aircraft Same as above I I l 4.5 Test conditions. The aircraft shall be complete (prepared for final delivery including pylons), preflight inspected, configured f
21、or flight, and verified to be mission capable with all systems operating properly immediately prior to the tests specified herein. No ground covers, tape, or other protective or absorbing coverings (except pitot tube covers) shall be installed inside or outside of the aircraft during the tests of 4.
22、6.1 and 4.6.2. Only pitot tube covers and other ground covers normally required for aircraft cleaning shall be utilized for the test of 4.6.4. All temperatures shall be at ambient. Al 1 watertight access closures (canopies, windows, doors, hatches) shall be fully opened and closed a minimum of five
23、times immediately prior to the start of a test. All access doors and panels required to be opened during mission performance or for maintenance or inspection at frequencies of- less than every 400 flight hours shall be opened and closed at least one time to break any paint seal prior to testing. 4.6
24、 Watertightness test. The tests may be tailored and changed with procuring activity approval to meet special needs of different aircraft. The tests specified herein shall be performed as follows: a. Ground watertightness test (see 4.6.1) b. Additional ground watertightness test-rainsoak (see 4.6.2)
25、c. Flight watertightness test (see 4.6.3) d. Aircraft cleaning watertightness test (see 4.6.4) 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-W-6729C 4.6.1 Ground watertightness test. The aircraft shall be parked with power off and subject to
26、a water spray system of a uniform minimum intensity between 5 and 9 inches per hour for a minimum of 20 minutes. The spray system water rate shall be measured at the surface of the aircraft by U.S. Heather Service approved rain gages located at the nose, tail and wing root areas of the aircraft, or
27、as designated by the procuring activity. The system shall spray uniformly downward over the entire aircraft and over the surfaces not shielded by the wings, at 45 degrees from vertical at aircraft side surface areas and horizontally at the nose section, tail section and surfaces shielded by the wing
28、s (see Figure 1). In order to ensure that the aircraft is tested in both stowed and flight configuration, the aircraft shall be tested with one wing folded and one wing spread if possible, or the test shall be conducted once with the aircraft in stowed configuration and once in flight configuration.
29、 this test, the aircraft shall be inspected in accordance with 4.7 and a test report issued in accordance with 6.3. a After WATER IN VERTICAL DIRECTION WATER IN (APPROX.) 45“ WATER IN (APPROX.) 45“ DIRECTION (STARBOARD SIDE) DIRECTION (PORT SIDE) L WATER IN (APPROX.) HORIZONTAL DIRECTION WATER IN (A
30、PPROX.) AT AREAS SHIELDED BY THE WINGS. WATER IN (APPROX.) HORIZONTAL DIRECTION HORIZONTAL DIRECTION (STARBOARD SIDE) (PORT SIDE) FIGURE 1. Ground watertightness test. 4.6.2. Additional ground watertiqhtness test - rainsoak. When specified by the procuring activity, the aircraft shall also be subjec
31、ted to a ground-rainsoak test (see 6.2) consisting of vertical rain spray at 1 to 2 inches per hour for 4 to 8 hours (see Figure 2). After this test the aircraft shall be inspected in accordance with 4.7 and a report issued in accordance with 6.3. 4 e a Provided by IHSNot for ResaleNo reproduction o
32、r networking permitted without license from IHS-,-,-_ - NIL-U-6729C 999990b 1845238 b48 MIL-W-6729C 4.6.3 -Fliqht watertightness test. The aircraft shall be flown in a heavy rain as defined by the U.S. Meather Service (at least 0.30 inches accumulation per hour) for a minimum of 15 minutes or as spe
33、cified by the procuring activity. During the test all compartments accessible in flight, such as cockpits and cabins, shall be inspected for leaks around canopies, windshields, escape hatches, cockpit venti lators and other inspection or access doors. inspected in accordance with 4.7 and a report is
34、sued in accordance with 6.3. Following the flight the aircraft shall be * 4.6.4 Aircraft cleaning watertiqhtness test. The aircraft shall be cleaned in accordance with the applicable weapon system cleaning manual (NAVAIR 01-1A-509 for Navy aircraft). After completion of the cleaning procedures, the
35、aircraft shall be inspected in accordance with paragraph 4.7 and a test report issued in accordance with 6.3. MATER IN VERTICAL DIRECTION FIGURE 2. Rainsoak simulation 4.7 Post test inspections. 4.7.1 Operational test and inspections. Immediately following the completion of the spray testing, the ai
36、rcraft shall be preflight checked, engines started and post start checked to confirm all systems are operationally capable for flight and mission performance. Any system malfunctions shall be immediately investigated to determine if the problem is associated with water intrusion or improper water co
37、ntrol (see 6.4.1). Defects shall be as defined in Table II. The aircraft shall be exposed to ambient temperature during this test, and the aircraft shall not be dried in any manner unless required for trouble shooting purposes during investigations of system malfunctions. When ambient icing conditio
38、ns exist, related problems shall also be investigated and documented in the test report (see 6.3). * 4.7.2 Inspection for watertightness areas. Areas classified as watertight in accordance with 3.1.1 shall be thoroughly inspected for any water intrusion, water migration from other areas and condensa
39、tion. 4.7.2.1 Defects for watertight areas. Any amount of water found in watertight areas during inspection constitutes a defect. identified as to the source of the water intrusion and the nature of the defect as a design or workmanship problem. Defects identification information shall be included W
40、atertight area defects shall be in the test report. I 0. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-W-b729C = 9999906 1845239 584 m MI L-W-6729C * 4.7.3. Inspection for non-watertight areas. Areas classified as non-watertight in accordance
41、 with paragraph 3.1.2, shall be thoroughly inspected for any water accumulation. * 4.7.3.1. Defects for non-watertiqht areas. Any water accumulation found during inspection in non-watertight areas constitutes a defect. shall be identified with the nature of the defect as a design or workmanship prob
42、lem. Defects identification information shall be included in the test report. Non-watertight area defects * 4.8 Classification of defects. Table II lists watertight/non-watertight defects. TABLE II. Classification of defects. C1 ass i f i cat ion 1 (Critical) 101 (Major) 102 103 201 (Minor) 2 (Criti
43、cal) Defects Water Intrusion Control - Design defect - Fabrication defect; Quality Water Accumulation - Improper flow path - Improper drainage design - Clogged drains Improper Sealing or Access Closure 6 5. PACKAGING This section is not applicable to this specification. 6. NOTES (This section contai
44、ns information of a general or explanatory nature that may be helpful, but is not mandatory.) 6.1 Intended use. Procedures for testing aircraft described herein are intended to ensure watertightness and proper drainage when the aircraft is exposed to natural humid and rainy environments or washing p
45、rocedures. 6.2 Acquisition requirements. Acquisition documents must specify the following: a. Titles, number, and date of the specification. b. Test(s) required (see 4.6). c. Type inspection(s1 required (see 4.7). a e a Provided by IHSNot for ResaleNo reproduction or networking permitted without lic
46、ense from IHS-,-,-* MIL-W-672C D Ob LBri5240 2Tb MIL-W-6729C d. Sampling plan indicating quantity, frequency and sequence of sample aircraft (see Table I). e. Appl i cab1 e spec if i c ai rcraf t design specifications . f. Tailoring as required, to fit the specific need of the structure or equipment
47、 of the aircraft. * 6.3 Data requirements. The following Data Item Descriptions (DIDS) must be listed, as applicable, on the Contract Data Requirements List (DD Form 1423) when this specification is applied on a contract, in order to obtain the data, except where DOD FAR Supplement 27.475-1 exempts
48、the requirement for a DD Form 1423. Reference Paragraph DID Number DID Title Suggested Tailoring 4.7 DI-NDTI-80809A Test reports Whenever possible use the contractors test report format The above DIDS were those cleared as of the date of this specification. The current issue of DOD 5010.12-C, Acquis
49、ition Management Systems and Data Requirements Control List (AMSDL), must be researched to ensure that only current, cleared DIDs are ci,ted on the DD Form 1423. 6.4 Definitions. Definitions listed herein pertain only to those items peculiar to this specification. 6.4.1 Water control. Water control is the control of the flow paths of rain or wash water or solvents which enter the aircraft non-watertight interior spaces to prevent degradation
