1、Designation: F330 16Standard Test Method forBird Impact Testing of Aerospace Transparent Enclosures1This standard is issued under the fixed designation F330; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision
2、.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This test method covers conducting bird impact te
3、stsunder a standard set of conditions by firing a packaged bird ata stationary transparency mounted in a support structure.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for informatio
4、n onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory li
5、mitations prior to use. For specific hazardstatements, see Section 8.2. Terminology2.1 Definitions:2.1.1 bird, nthe carcass that is used to impact the testarticle.2.1.2 bird package, nthe bird and container that encasesthe bird to prevent disintegration enroute to target.2.1.3 gun, nthe device that
6、propels the bird toward thetarget.2.1.4 sabot, nthe container that is used to carry the birdpackage down the gun barrel.2.1.5 stripper, nthe device that stops the sabot at the endof the gun barrel so that only the bird package impacts the testarticle.2.1.6 test article, nthe transparency and support
7、ing struc-ture.3. Summary of Test Method3.1 This test method employs a smooth-bore bird gun thatfires a chicken carcass so that it impacts a stationary aerospacetransparency mounted in a supporting structure.3.2 The specific parameters described by this test methodare:3.2.1 Bird weight and condition
8、,3.2.2 Bird velocity, and3.2.3 Instrumentation.4. Significance and Use4.1 This test method shall be used for: bird impact testing ofaircraft crew compartment transparencies and supporting struc-ture to verify the design; compilation of test data for use inverification of future transparency and supp
9、orting structuredesign and analytical methods; and comparative evaluation ofmaterials.5. Apparatus5.1 Gun, compressed gas, conforming in principle to Fig. 1,comprising:5.1.1 Pressure Tank, of capacity and working pressure asdiscussed in Note 1.NOTE 1A gun capable of propelling a 4-lb (1.81-kg) bird
10、in excess of650 knots (334 m/s) has a barrel 60 ft (18.3 m) long, bore of 6 in.(153 mm), and a pressure tank volume of 30 ft3(0.849 m3) with anallowable working pressure of 250 psi (1.725 106Pa).5.1.2 Release Mechanism, comprised of a firing solenoid,diaphragm, and a cutter. Upon initiation of the f
11、iring sequence,the release mechanism allows the compressed gas stored in thepressure tank to flow rapidly into the gun barrel and propel theprojectile.NOTE 2The most common designs normally use either one or twodiaphragms in the release mechanism. In the single diaphragm design, thediaphragm is mech
12、anically ruptured upon firing (see Fig. 1). In the dualdiaphragm system, pressurized gas between the two pressurized gasdiaphragms is bled to initiate firing by allowing the stored gas to bursteach diaphragm in rapid succession.5.1.3 Barrel (Launch Tube), a smooth bore tube that guidesthe packaged b
13、ird (and sabot if used) during its acceleration bythe expanding air from the pressure tank. The bore and lengthof the barrel is chosen both to accommodate the largest of theprojectiles to be used and for the overall performance require-ments of the gun.1This test method is under the jurisdiction of
14、ASTM Committee F07 onAerospace and Aircraft and is the direct responsibility of Subcommittee F07.08 onTransparent Enclosures and Materials.Current edition approved April 1, 2016. Published April 2016. Originallyapproved in 1979. Last previous edition approved in 2010 as F330 10. DOI:10.1520/F0330-16
15、.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.1.4 Sabot Stripper typically mounted at the end of thelauncher tube. The purpose of the sabot stripper is to arrest ordeflect the sabot, allowing only the packaged bird to impact thet
16、est article.5.2 Velocity Measurement System:5.2.1 The essential features of the velocity measurementsystem are that it be accurate and repeatable, not be triggeredby small stray objects that are traveling with the projectile, andnot alter the flight path or damage the projectile.5.2.2 Preferred velo
17、city measurement systems use timingstations, located between the gun barrel and the test specimen,which are triggered by the projectiles breakage of a mechanicallink “break wire” or through the interruption of a light beam.The velocity is then computed and averaged from the knowndistances between th
18、e timing stations. Rapid sequencephotography, in conjunction with a background gridwork, issuitable for use as a redundant system.NOTE 3When using a light beam measuring system under high-humidity conditions, it is possible that the bird can become enveloped ina cloud of water droplets that could ca
19、use triggering of the light beams andthe bird package shown in the film might not be clear. When using a“break wire” system, it is imperative that the tension of the wires beadjusted to within close tolerances in order to obtain consistent results.5.3 Environmental Control:5.3.1 The environmental co
20、ntrol apparatus is used to heat orcool the test article to the desired temperature at the time ofimpact. The environmental control required shall be capable ofproviding the temperature range surrounding the test articlethat would critically affect the physical properties of aircrafttransparencies. T
21、his range is normally 65F (54C) to 250F(121C). The facility shall be capable of providing thesetemperatures for a sufficient time to achieve steady-statetemperature gradients as required in the test article. A uniformsource of heat or cold shall be provided; that is, no “cold” or“hot” spots shall be
22、 developed in the test article, and this shallbe verified by the use of thermocouples placed at strategicpoints throughout the test article or by use of infrared (pho-tography) thermographs.5.3.2 Enclose the mounted test article and circulate precon-ditioned air within this enclosure, stabilize the
23、test article at thedesired test temperature, and remove the enclosure immedi-ately before the impact test. Anti-icing or defogging systems,or both, shall be used, if required by the customer.NOTE 4A variety of techniques have been successfully used toachieve environmental control. For example:Acoola
24、nt, carbon dioxide orliquid nitrogen, is mixed with air to cool the test article below ambienttemperatures. Hot air, heat lamps, or energized electrical conductivecoatings within the test article are used to raise interior or exteriortemperatures.5.4 Test Instrumentation:5.4.1 Weight MeasurementThe
25、weight scale shall have anaccuracy of at least 0.063 oz (1.8 g).5.4.2 Mounting Angle Measurements (Pitch, Roll andYaw)The instrument for measuring the angle, at which thetest article or its support structure is mounted, shall have anaccuracy of14 (0.004 36 radian).5.4.3 Temperature MeasurementThe in
26、strument systemfor measuring temperatures shall have an accuracy of 65F(2.8C).5.4.4 Velocity MeasurementThe instrumentation usedwith the velocity measurement system shall provide for anoverall system accuracy within 62%.5.4.5 Rapid Sequence, at least one high-speed camera shallbe used to provide rec
27、ords of the bird impacting the target. Thecamera lighting conditions and controlling instrumentationshall be adjusted to provide a minimum of the followingcamera frames per second at impact:F 5 100015 V or (1)F 5 100011.53 v (2)where:F = exposure rate (frames per second),V = projectile velocity (ft/
28、s), andv = projectile velocity (m/s)One technique to verify camera exposure rate during theimpact sequence is to place timing marks on the film at a rateof at least 100/s and at an accuracy of at least 1 % (see Table1 for camera exposure rate versus impact velocity).6. Materials6.1 Bird:FIG. 1 Repre
29、sentative Air GunF330 1626.1.1 The bird combined with the packaging forms theprojectile that impacts the test article. If a real carcass isselected, both domestic and wild birds are permitted dependingon the required weight. The standard weight of the bird used inthis test shall be 4 lb (1.81 kg), u
30、nless a different weight isrequired by the certifying authority. Use a chicken as the birdfor this standard weight. Either freshly kill the bird and store ina sealed container at 60 to 80 F for up to 8 h, or refrigerate upto one day, or freeze immediately after killing for future use.For a refrigera
31、ted bird, remove the bird from refrigeration andallow it to warm for approximately 4 h (for a 4-lb bird) beforeuse. Thaw a frozen bird carcass at normal room temperature forapproximately 24 h (for a 4-lb bird) before use. The minimuminternal bird temperature shall be 60F (15.5C) at the time ofuse.6.
32、1.2 Weigh the bird just before use. To achieve the requiredweight, the carcass shall be either trimmed, or water (or gelcontaining 98 % water) shall be added as long as the carcassoriginal weight does not change more than 10 % (see Table 2).Remove only portions of the birds extremities (wings andleg
33、s) when a weight reduction is necessary.6.2 Bird Container:6.2.1 The bird container is used to prevent the bird frombecoming damaged or grossly deformed before impacting thespecimen. Construct it so as to form a cylindrical projectile andof materials that minimize its effect during impact. Materials
34、commonly used in fabricating the bird container include nylon,cotton or polyethylene bags, cardboard cartons, and expandedshapes. The weight of the bird container shall not exceed 10 %of the total projectile weight as indicated in Table 2 for thestandard projectile weights.6.3 Sabot:6.3.1 The sabot
35、is used to protect and support the packagedbird during the launching and must fit intimately with the birdpackage and gun barrel.6.3.2 The packaged bird remains in the cavity of the sabotuntil the sabot reaches the end of the launcher at which pointthe sabot is arrested by the stripper and only the
36、packaged birdis allowed to continue on to impact the test article.Asabot andstripper combination shall be designed so that either all of thesabot is arrested by the stripper or the fragments of sabot whichcontinue past the stripper are not considered to be significantlydetrimental to the test articl
37、e as observed in rapid sequencephotographic records.6.4 Crew SimulationManikins, modeling clay, styrofoamwitness plates, or other flight crew representation devices shallbe used to record impact effects on the crew, if required by thecustomer.6.5 Coolant:6.5.1 Carbon Dioxide and Liquid NitrogenFor i
38、ntroduc-tion of preconditioning air for temperature control. Cautionshall be exercised when using these materials. See 1.3.7. Transparency and Supporting Structure Test Article7.1 Unless otherwise specified, the transparencies and sup-porting structure described as the test article shall be produc-t
39、ion parts and assemblies. Mount the transparency at the angleof incidence in a production structure restrained at designlevels of rigidity. Install aircraft quality fasteners with appro-priate aircraft installation procedures. The test range shallcontain firm tie-down points for mounting the test ar
40、ticles.8. Hazards8.1 Operation and maintenance of the gun shall be such thatmaximum personnel protection is provided at all times. Per-sonnel safety shall be the prime consideration in developingoperating procedures for any facility. Design pressure linesaccording to approved engineering procedures
41、and provideadequate safety factors.8.2 Rope or fence off the test area, including the area fromthe muzzle of the gun to the target backstop and adequatesurrounding area. Warning signals shall make the evacuationarea apparent to personnel before a firing. Give adequateaudible warnings to inform all p
42、ersonnel in the immediate areaof the status of the test from the time the announcement to clearthe area is given until the all-clear announcement is given.8.3 After a warning is given to clear the area before a firing,one of the operating crew shall visually check to assure thatthere are no personne
43、l in the test area.8.4 If it is necessary for personnel to enter the test area afterthe announcement to clear the area is given, take adequatesafeguards to assure that the gun cannot either accidentally ordeliberately be fired until the area is again cleared.8.5 Provide means to prevent personnel fr
44、om entering thetest area after the gun is pressurized.TABLE 1 Camera Exposure Rate Versus Bird Impact VelocityVFBird Impact Velocityft/s m/sExposure Rate(Frames/Second)100 30.5 1500200 61.0 2000300 91.4 2500400 122.0 3000500 152.0 3500600 183.0 4000700 213.0 4500800 244.0 5000900 274.0 55001000 305.
45、0 60001100 335.0 65001200 366.0 7000TABLE 2 Bird Projectile WeightsWSAWNBBWACWPD2.00 0.063 lb 2 lb 0.20 lb 0.20 lb(0.91 0.028 kg) (0.91 kg) (0.09 kg) (0.09 kg)4.00 0.125 lb 4 lb 0.40 lb 0.40 lb(1.81 0.057 kg) (1.81 kg) (0.18 kg) (0.18 kg)8.00 0.250 lb 8 lb 0.80 lb 0.80 lb(3.63 0.113 kg) 3.63 kg) (0.
46、36 kg) (0.36 kg)AWS= projectile weight including bird and bird container.BWNB= nominal bird weight.CWA= maximum allowable weight to be removed from or added to the bird.DWP= maximum allowable weight of the bird container.F330 1638.6 Wash the test area thoroughly at the end of a period ofshooting (su
47、ch as a shift or day) and remove and dispose of thebird debris. The area shall be thoroughly sprayed with adisinfectant to kill germs and minimize odor.8.7 The test range shall contain shields to protect personneland property from debris resulting from the impact.9. Gun Calibration9.1 Calibrate the
48、gun, using the standard bird weight, todetermine its performance over the velocity range to be used.Develop curves showing the relation between bird launchvelocity and the amount of pressure required.10. Standardization10.1 Align the mounted test article or references on thesupport structure to the
49、gun barrel axis to within 612 ofthespecified angle.10.2 The center of the bird shall impact a projected targetpoint orthogonal to the projectile trajectory within a 1-in.(25.4-mm) radius. Probability and associated confidence levelestimates should be historically supportable for various impactpoint predictions.10.3 Do not mount the test article impact point any closerthan ten barrel diameters (bore or inside diameter) from the endof the gun barrel.11. Procedure11.1 Visually inspect the mounted test article before impact-ing and record
