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 revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions.Copyright 2015 SAE InternationalAll rights reserved. No part of this publi
3、cation may 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: +1 724-776-4970 (out
4、side USA)Fax: 724-776-0790Email: CustomerServicesae.orgSAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedbackon this Technical Report, please visithttp:/www.sae.org/technical/standards/AS6254AAEROSPACESTANDARDAS6254 REV. AIssued 2012-02Revised 2015-12Superseding AS6254Minimum P
5、erformance Standard for Low Frequency Underwater Locating Devices (Acoustic)(Self-Powered)RATIONALETechnology exists to increase the minimum Low Frequency Underwater Locating Devices (ULD) operating life without changes to the form, fit or general function of an installed ULD. For aircraft search an
6、d recovery in extremely remote areas, a Low Frequency ULD operating for 30 days may not be sufficient. This revision includes an increase of the minimum operating life in 4.7 from 30 to 90 days along with an added reference to the recently published ARINC Standard 677 regarding the installation of t
7、he ULD on aircraft.1. SCOPEThis SAE Aerospace Standard (AS) covers ULDs utilized in finding submerged aircraft. Such ULDs are installed within the aircraft in a manner that they are unlikely to become separated during crash conditions. The low frequency ULD should be attached to the airframe in acco
8、rdance with the manufacturers recommendations in order to maximize the underwater detection range. ARINC Standard 677 also provides installation guidance for Low Frequency ULDs.1.1 PurposeThis Aerospace Standard specifies minimum performance standards for low frequency acoustic ULDs which are primar
9、ily intended for use with both fixed and rotary wing civil aircraft.2. REFERENCES2.1 Applicable DocumentsThe 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 i
10、ssue in effect on the date of the purchase order. In the event of conflict 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 obt
11、ained.SAE INTERNATIONAL AS6254APage2of 82.1.1 SAE PublicationsAvailable from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or +1 724-776-4970 (outside USA), www.sae.org.AS8045 Minimum Performance Standard for Underwater Locating Devic
12、es (Acoustic) (Self-Powered)2.1.2 ASTM PublicationsAvailable from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.astm.org.ASTM D1141-98 Standard Practice for the Preparation of Substitute Ocean Water2.1.3 RTCA PublicationsAvailable
13、from Radio Technical Commission for Aeronautics Inc., 1150 18th Street, NW, Suite 910, Washington, DC 20036, Tel: 202-833-9339, www.rtca.org.RTCA/DO-160G Environmental Conditions and Test Procedures for Airborne Equipment2.1.4 ARINC PublicationsAvailable from ARINC Industry Activities, 16701 Melford
14、 Blvd., Suite 120, Bowie, MD 20715, Tel: 240-334-2578,www.aviation-.ARINC 677 Installation Standards for Low Frequency Underwater Locator Beacon (LF-ULB)2.2 DefinitionsThe word “shall” is used to express an essential requirement where compliance is mandatory.3. GENERAL STANDARDS3.1 MaterialMaterial
15、shall be of a quality which experience or tests, or both, have demonstrated to be suitable and dependable for use in aircraft. The correct functioning of the ULD shall not be impaired by any change of material properties arising from the tests defined in Sections 5 and 6.3.2 WorkmanshipWorkmanship s
16、hall be consistent with high grade aircraft instrument manufacturing practice.3.3 CompatibilityIf components are individually acceptable but require matching for proper operation, they shall be identified in a manner that shall ensure performance to the requirements of this AS.3.4 Interchangeability
17、Components or systems which are identified with the same manufacturers part or model number shall be physically and functionally interchangeable.SAE INTERNATIONAL AS6254APage3of 83.5 Flammability and Fire TestThe exposed surfaces of the ULD and mounting shall be non-flammable. The ULD shall be incap
18、able of sustaining or initiating a fire or rupturing, or both, with or without fragmentation, due to a dead short of the power source.3.6 Power SourceMeans shall be provided to enable the ULD power source to be checked for voltage and longevity in its installed position. Such checks shall be defined
19、 in the ULD manufacturers instruction manual.3.7 IdentificationThe following information shall be legible and, with the exception of battery replacement date, be indelibly marked on the ULD or on the nameplate attached. Markings on the ULD are to be as large as is practical.a. Name of instrument.b.
20、Manufacturers part number.c. Manufacturers serial number.d. Federal Aviation Administration (FAA) Technical Standard Order (TSO) number, if applicable (or SAE AS number/revision or equivalent approval identification).e. Manufacturers name or trademark.f. Battery replacement information.4. MINIMUM PE
21、RFORMANCE STANDARDSThe manufacturer shall conduct sufficient tests to prove compliance with this Aerospace Standard.4.1 ActuationThe Low Frequency ULD shall activate automatically when submerged in either fresh or salt water, at a depth no greater than 9 m (29.5 feet) within 4 hours after immersion.
22、 The ULD shall remain activated to a depth of at least 6,096 m (20,000 feet). NOTE: If the ULD is subjected to negligent or accidental contamination with water, either immersed or sprayed, (that is, other than in its operational mode) it shall, on drying out, revert to its original dormant state. If
23、 the ULD is intentionally or unintentionally exposed to activation pressure (for example during aircraft pressurization testing), it shall revert to its original dormant state when the pressure is reduced below the activation threshold.4.2 Operating Temperature-2 C (28 F) to +38 C (100 F).4.3 Radiat
24、ion Pattern80% of a spherical pattern (4.8.1 and 4.8.2 apply).4.4 Operating Frequency8.8 kHz 1 kHz.SAE INTERNATIONAL AS6254APage4of 84.5 Pulse Length10.0 ms MINIMUM.4.6 Repetition Rate0.1 pulse/s MINIMUM.4.7 Operating Life90 days.4.8 Acoustic Outputs on Activation4.8.1 Initial OperationA minimum of
25、100 N/m2(1,000 dyne/cm2) rms (during the pulse) pressure normalized to 1 m range, that is, at a level of 160 dB versus 1 Pa at 1 m.4.8.2 Immediately After 90 Days Continuous OperationA minimum of 70.8 N/m2(708 dyne/cm2) rms (during the pulse) pressure normalized at 1 m range, that is, at a level of
26、157 dB versus 1 Pa at 1 m.5. TEST PROCEDURES (ENVIRONMENTAL)Sequence may be in any order. Instrument with ULD in its inoperative mode at the commencement of each test clause and no ULD activation by test personnel during environmental tests. Operational or functional tests as required shall be condu
27、cted before and after each clause to verify the operational condition of the ULD under test.5.1 CondensationWith the ULD in the most critical position, cold soak at -9 C 3 C (+16 F 5 F) for 6 hours and then immediately place in a chamber maintained at +35 C 3 C (+95 F 5 F) at a relative humidity of
28、95% 5% for 18 hours. Repeat this environmental cycle for a total of 15 times.During this test there shall be no activation of the ULD transmitter or corrosion of vital parts.5.2 Temperature Storage (Temperature)The ULD shall be subjected to the Ground Survival Low and High Temperature test requireme
29、nts specified in RTCA/DO-160G, Section 4.5, Category D2.During this test there shall be no activation of the ULD transmitter.5.3 Temperature VariationThe ULD shall be subjected to the test requirements specified in RTCA/DO-160G, Section 5, Category A using -55 C (-67 F) and +70 C (+158 F) for low an
30、d high operating temperatures, respectively.During this test there shall be no activation of the ULD transmitter.SAE INTERNATIONAL AS6254APage5of 85.4 VibrationThe ULD shall be subjected to the test requirements specified in RTCA/DO-160G, Section 8 using Figure 8-4, Curve C1 (fixed wing) and Table 8
31、-2b, Curve G (rotary wing).During this test there shall be no activation of the ULD transmitter.5.5 Altitude, Decompression and Overpressure5.5.1 AltitudeThe ULD shall be subjected to the test requirements specified in RTCA/DO-160G, Section 4.6.1, Category D2.During this test there shall be no activ
32、ation of the ULD transmitter.5.5.2 DecompressionThe ULD shall be subjected to the test requirements specified in RTCA/DO-160G, Section 4.6.2 except that the reduction in pressure shall take place within 2 seconds to a pressure equivalent to 13,746.5 m (45,100 feet) altitude. During this test there s
33、hall be no activation of the ULD transmitter.5.5.3 OverpressureULDs that utilize a pressure activation mechanism shall be subjected to the test requirements specified in RTCA/DO-160G, Section 4.6.3, except that the overpressure shall be 200 kPa. Automatic activation of the ULD is acceptable during t
34、his test provided that it reverts to its original dormant state when thepressure is reduced below the activation threshold.5.6 Fluid Immersion (Fluids Susceptibility)The ULD shall be subjected to the immersion test requirements specified in RTCA/DO-160G, Section 11, Category F using fluids most like
35、ly to cause the ULD to become inoperative. After drying out, the ULD shall not have deteriorated such that it would not satisfy the requirements of Section 4.Alternatively, an analysis may be used to demonstrate the ULDs resistance to such fluids.5.7 Induced Signal SusceptibilityThe ULD shall be sub
36、jected to the relevant test requirements as specified in RTCA/DO-160G, Section 19, Category ZC.During this test there shall be no activation of the ULD transmitter.5.8 Magnetic EffectThe ULD shall be subjected to the test requirements specified in RTCA/DO-160G, Section 15 and shall meet the Category
37、 Z requirement.5.9 Sand and DustThe ULD shall be subjected to the test requirements specified in RTCA/DO-160G, Section 12, Category S.During this test there shall be no activation of the ULD transmitter and there shall be no sand/dust lodged in vital parts such that the ULD would not satisfy the req
38、uirements of Section 4.SAE INTERNATIONAL AS6254APage6of 85.10 Salt Spray (Salt Fog)The ULD shall be subjected to the test requirements specified in RTCA/DO-160G, Section 14, Category S (fixed wing) and Category T (rotary wing).During this test there shall be no activation of the ULD transmitter and
39、there shall be no corrosion of vital parts such that the ULD would not satisfy the requirements of Section 4.5.11 Fungus ResistanceThe ULD shall be subjected to test requirements as specified in RTCA/DO-160G, Section 13, Category F.During this test there shall be no activation of the ULD transmitter
40、 and there shall be no fungus growth developed in vital parts such that the ULD would not satisfy the requirements of Section 4.5.12 Performance Verification (Environmental)On completion of all tests included in 5.1 through 5.11, the ULD shall meet all the requirements of Section 4.5.13 Salt Water I
41、mmersionThis test is performed once only. (Note this is a passive test and does not require continuous monitoring.) The ULD shall be submerged and operating in a standard seawater solution (ASTM D1141-98 or equivalent), at a pressure appropriate for continuous activation, for a period of 90 days. Th
42、e test tank shall be non-metallic and throughout the test the water shall be maintained between +10 C (+50 F) and +21 C (+70 F). At the end of 90 days, the ULD shall be operating as specified in Section 4 and there shall be no signs of seepage or leakage into the ULD.6. TEST PROCEDURES (CRASH SURVIV
43、ABILITY)The ULD shall be subjected to crash survivability testing, performed in the order shown below, without making any repairs or modifications between tests. Operational or functional tests as required shall be conducted before and after each clause to verify the operational condition of the ULD
44、 under test.6.1 Impact ShockThe ULD shall be assembled to a suitable fixture using its recommended mounting arrangement. The assembly shall then be subjected to:a. A half sine-wave impact shock of at least 5 ms duration and a peak acceleration of 1,000 g applied to each of the three orthogonal axes.
45、ORb. A half sine-wave impact shock of at least 6.5 ms duration and a peak acceleration of 1,700 g applied to the axis most vulnerable to damage.6.2 ImpactWhen assembled in its recommended mounting arrangement, the ULD shall be placed on an unyielding surface. An impactor, consisting of a steel penet
46、rator (Figure 1) with a rigidly attached mass is required. The penetrator shall have a maximum dimension across the surface of the protrusion of 0.64 cm (0.25 inch) by 2.5 cm (1.0 inch). This protruding surface shall impact the ULD. The total mass of the impactor shall be 25 kg (55 pounds). The impa
47、ctor shall be dropped on the ULD from a height of 15 cm (6.0 inches) above the surface of the ULD such that at least half of the penetrator impacts within a 2.5 cm (1.0 inch) radius of the most vulnerable point of the ULD.SAE INTERNATIONAL AS6254APage7of 82.5 cm(1.0 in)0.64 cm(0.25 in)Maximum2.5 cm(
48、1.0 in)MaximumFigure 1 - Dimensions of penetrator6.3 Static CrushWhen assembled in its recommended mounting arrangement, the ULD is to be exposed to a static crush force of 22.4 kN (5,000 lbf) continuously for 5 minutes. The crush force is to be applied in the most critical direction. The crush forc
49、e may be applied by placing the ULD between two flat surfaces and bringing the surfaces together until the 22.4 kN (5,000 lbf) force is developed.6.4 PressureThe ULD is to be exposed to an external pressure of 60 MPa (8,700 lbf/in2) for a period of 5 minutes. The pressure, equivalent to that of an ocean depth of 6,096 m (20,000 feet), shall be applied as a uniformly distributed force
