Downloaded from https://www.everyspec.com / MIL-STD-81OC 4 Table 515.2-11 Acoustic Test Levels for Assembled Externally Carried Aircraft Stores Functional Test Lol, S, 6, 7= ZOI,Og (ql) + 11 Log (X) + 7 Log (l-cOs~) + 72 f. 2, 3 = 600 Log (X/R) + C Endurance Test Lo 1, 5, 6, 7 = Z. Log (q2/ql) + 2.s LOg ‘(N/3T)+ functional Ievel f. 2, 3 = 600 Log (X/R) + C Definitions ql = maxim~ captive flight dyn~ic pressure (lbs/ft2)S 1800 q2 = 1200 psf or maximum captive flight dynamic pressure (whicheveris lower) (lbs/ft2) N = maximum number of anticipated service missions (minimumN = 3) Rg= local radius of store in inches X = distance from nose of store along axis of store in inches T .
test time in hours (minimumT = 1 hour) C = -200 locations within one D of either aft end of store or aftward of re-entrant angle C = 400 all other locations A = -6 dB/octave f. >400 Hz A = -2 dB/octave f. ~400 Hz D#. maximm stOre dimeter in inches 1. P = local nose cone angle at X equals 1 ~ ~-~)(R/x) ‘ref ‘ig RepresentativeParametric Values to be used for captive flight when specific par~eters are not available. Local Nose f. f. f.
N Cone Angle q Nose Middle Aft Store Type Endurance Degrees max Section Section Section Air-to-Air Missile 100 69 1600 .500 1000 500 Air-to-GroundMissile 3 12 1600 800 630 630 Instrument Pod 500 69 1800 500 1000 500 Reusable Dispenser 50 11 1200 630 1000 400 Demolition Bomb 3 24 1200 500 1000 630 Flat Nose Store 3 90 1200 400 630 315 METHOD 515.2 515.2-B 1