1、Designation: F 330 89 (Reapproved 2004)Standard Test Method forBird Impact Testing of Aerospace Transparent Enclosures1This standard is issued under the fixed designation F 330; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the y
2、ear of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method covers condu
3、cting bird impact testsunder 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 the standard. The values given in parentheses are forinformation only.1.3 This standard does n
4、ot 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 limitations prior to use. For specific hazardstatements, see Sec
5、tion 8.2. Terminology2.1 Definitions:2.1.1 birdthe carcass that is used to impact the test article.2.1.2 bird packagethe bird and container that encases thebird to prevent disintegration enroute to target.2.1.3 gunthe device that propels the bird toward thetarget.2.1.4 sabotthe container that is use
6、d to adapt the birdpackage to the gun barrel.2.1.5 stripperthe device that stops the sabot at the end ofthe gun barrel so that only the bird and package exits from thebarrel.2.1.6 test articlethe transparency and supporting struc-ture.3. Summary of Test Method3.1 This test method employs a smooth-bo
7、re 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,3.2.2 Bird velocity, and3.2.3 Instrumentation.4. Significance and Use4.1 This t
8、est method may 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 supporting structuredesign and analytical methods; and comparative evaluation ofmateri
9、als.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 in excess of650 knots (334 m/s) has a barrel 60 ft (18.3 m) long, bore of 6 in. (1
10、53mm), and a pressure tank volume of 30 ft3(0.849 m3) with an allowableworking pressure of 250 psi (1.725 3 106Pa).5.1.2 Release Mechanism, comprised of a firing solenoid,diaphragm, and a cutter. Upon initiation of the firing sequence,the release mechanism allows the compressed gas stored in thepres
11、sure 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 mechanically ruptured upon firing (see Fig. 1). In the dualdiaphragm system, pressur
12、ized 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 bird (and sabot if used) during its acceleration bythe expanding air from the pre
13、ssure 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.5.1.4 Sabot Stripper may be mounted at the end of thelauncher tube. The purpose of the sabot stripper is to arrest ordeflect th
14、e sabot, allowing only the packaged bird to impact thetest article.1This test method is under the jurisdiction of ASTM Committee F07 onAerospace and Aircraft and is the direct responsibility of Subcommittee F07.08 onTransparent Enclosures and Materials.Current edition approved Oct. 1, 2004. Publishe
15、d October 2004. Originallyapproved in 1979. Last previous edition approved in 1999 as F 330 89 (1999).1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2 Velocity Measurement System:5.2.1 The essential features of the velocity measur
16、ementsystem are that it be accurate and repeatable, not be triggeredby small stray objects that may be traveling with the projectile,and not alter the flight path or damage the projectile.5.2.2 Preferred velocity measurement systems use timingstations, located between the gun barrel and the test spe
17、cimen,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 the timing stations. Rapid sequence photog-raphy, in conjunction with a background gridwork, m
18、ay beused to provide 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 cause triggering of the light beams andthe bird package shown in the film might not be clear
19、. 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 control apparatus may be used toheat or cool the test article to the desired temperature at
20、thetime of impact. The environmental control required shall becapable of providing the temperature range surrounding the testarticle that would critically affect the physical properties ofaircraft transparencies. This range is normally 65F (54C)to 250F (121C). The facility shall be capable of provid
21、ingthese temperatures 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 developed in the test article, and this shallbe verified by the use of thermocouples
22、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 test article at thedesired test temperature, and remove the enclosure immedi-ately bef
23、ore the impact test. A coolant, carbon dioxide or liquidnitrogen, may be mixed with the air to cool the air belowambient temperatures. Hot air, heat lamps, or energized elec-trical conductive coatings within the test article may be used toraise interior or exterior temperatures. Antiicing or defoggi
24、ngsystems, or both, may also be required.5.4 Test Instrumentation:5.4.1 Weight MeasurementThe 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 structur
25、e is mounted, shall have anaccuracy of14 (0.004 36 radian).5.4.3 Temperature MeasurementThe instrument 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 accura
26、cy within 62%.5.4.5 Rapid Sequence, at least one high-speed camera shallbe used to provide records 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 1000 1 5 V o
27、r (1)F 5 1000 1 1.53 v (2)where:F = exposure rate (frames per second),V = projectile velocity (ft/s), andv = projectile velocity (m/s)Timing marks may be automatically placed on the film at arate of at least 100/s and at an accuracy of at least 1 % to verifythe camera exposure rate during the impact
28、 sequence (seeTable 1 for camera exposure rate versus impact velocity).6. Materials6.1 Bird:6.1.1 The bird combined with the packaging forms theprojectile that impacts the test article. If a real carcass isselected, it may be either a domestic or wild bird depending onthe required weight. The standa
29、rd weight of the bird used inthis test shall be 4 lb (1.81 kg). Use a chicken as the bird forthis standard weight. Either freshly kill the bird just before use(within 1 h) or freeze immediately after killing for future use.Store the frozen bird at 0F (18C) or lower for no more thanFIG. 1 Representat
30、ive Air GunF 330 89 (2004)230 days. Thaw a frozen bird carcass at normal room tempera-ture for approximately 24 h (for a 4-lb bird) before use and theminimum internal body temperature shall be 60F (15.5C) atthe time of use.6.1.2 Weigh the bird just before use. To achieve the requiredweight, the carc
31、ass may be either trimmed, or water (or gelcontaining 98 % water) may 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 andlegs) when a weight reduction is necessary.6.2 Bird Container:6.2.1 The bird conta
32、iner 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. Materialscommonly used in fabricating the bird container include nylon,cotton or polyeth
33、ylene 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 is used to protect and support the packagedbird during the launching and must f
34、it 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 packaged birdis allowed to continue on to impact the test article. A sabot ands
35、tripper 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 article as observed in rapid sequencephotographic records.6.4 Crew SimulationManiki
36、ns, modeling clay, styrofoamwitness plates, or other flight crew representation devices maybe used to record impact effects on the crew.6.5 Coolant:6.5.1 Carbon Dioxide and Liquid NitrogenFor introduc-tion to preconditioning air for temperature control. Cautionshould be exercised when using these ma
37、terials. 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-tion parts and assemblies. Mount the transparency at the angleof incidence in a production structure restra
38、ined 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 articles.8. Hazards8.1 Operation and maintenance of the gun shall be such thatmaximum personnel protection i
39、s 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 and provideadequate safety factors.8.2 Rope or fence off the test area, including the area fromthe muzzle
40、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 personnel in the immediate areaof the status of the test from the time the announcement to clearthe area is
41、 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 personnel in the test area.8.4 If it is necessary for personnel to enter the test area afterthe announcement to cl
42、ear 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 from entering thetest area after the gun is loaded.8.6 Wash the test area thoroughly at the end of a period
43、ofshooting (such as a shift or day) and remove and dispose thebird debris. The area may 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 Calib
44、rate the 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.TABLE 1 Camera Exposure Rate Versus Bird Impact VelocityVFBird Impact Velocityft/s m/sExpos
45、ure 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 305.0 60001100 335.0 65001200 366.0 7000TABLE 2 Bird Projectile WeightsWSAWNBBWACWPD2.00 6 0.063 lb 2 lb 0.20 lb 0.20 lb(0.91 6 0.028 kg) (0.91 kg) (
46、0.09 kg) (0.09 kg)4.00 6 0.125 lb 4 lb 0.40 lb 0.40 lb(1.81 6 0.057 kg) (1.81 kg) (0.18 kg) (0.18 kg)8.00 6 0.250 lb 8 lb 0.80 lb 0.80 lb(3.63 6 0.113 kg) 3.63 kg) (0.36 kg) (0.36 kg)AWS= projectile weight including bird and bird container.BWNB= nominal bird weight.CWA= maximum allowable weight to b
47、e removed from or added to the bird.DWP= maximum allowable weight of the bird container.F 330 89 (2004)310. Standardization10.1 Align the mounted test article or references on thesupport structure to the gun barrel axis to within 612 ofthespecified angle.10.2 The center of the bird shall impact a pr
48、ojected 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
49、(bore or inside diameter) from the endof the gun barrel.11. Procedure11.1 Visually inspect the mounted test article before impact-ing and record any defects.11.2 Mark the impact point without damaging the testarticle, position and instrument as desired the simulated crew,and position and check the test instrumentation.11.3 Proceed with the test article thermal conditioning if thetest temperatures are different from ambient temperatures.11.4 Prepare the bird and packaging. Record the weights ofthe various components.11.5 Insert the packaged bird into
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