F~OJECT ABSTTIACTS
Chief: Dr. James A. FeoJ;le.i • ..::::-.
1. Fro.1e:~t tit-le: A.~ol.4s"L: ~ounaing of the Atmcspbe:r-e
f':roject. sdentist.:;: Dr. :. A. i'eople:3, Jr., Dr. i•lor:ua.n
Haskell
Summary cf In-Laborat.:'lry ;·,ork:
'When large explosions i1av-;' o>!curred, it J·.as been observed that the soWla was
heard locally, say up to ::5 mile:s, and als.:> at dbtances of 100 to 200 miles, but
that nothinf; wa:; reard at intermediate distan~es. This phenomeru11can only be
explained by assumjng that the sound ts refracted into ths atmosphere over the 1n-
termedi2te observers and then is bent back down to the ;nore distant areas. For t~ds
to occur t.ho velocity of propagation must first decrease with altitude and then
increase &!&in to a value at least as lar~e a3 ground velocity. this is due to a
decrease of temrerature up t.o the tropopause followed by an increase in temperature
above that level. V:inds also have an appreciable affect which can be determined
from asymmetrical propa~ation.
Up to abo~t 1946 most data on this phenomenon had been obt&ined by taking
polls after accidental eaplosions had occurred. Zones ot audibility were mapped out
and ~ener.al conclusions then drawn. Very lit.tle systematic w·ork was done in \Which
accurate travel tiAs and other factors were obtair.ed. Beginning in 1~46 at these .
laboratories, a systematic study of these pr"p~at!on anomalies were started. Sound~
ran5ing detectors ware set up in arr&Js, so thsarvations h; "te bec!n tG.k6b ih the vicinity of Fairbanl:s• Alaska for in!or.." t on o.t
~.I"i J.igtj latitud~s4 · Ob~er.vatj,.dn,; .ha•e been taken near the Panama Carial Zone for
~:ci~Uiional information i.i1 tbt: !r#i.csi
The sounds produced by rockets launched a\. .k..1ar.togordo have been recol'd~d .~ith
acousti= detector arrays located on the gro1nd neer the rocket trajectory. From data
gath-=red in this nt£11Iler, soraa inoic~ ti.m!:' of apper air te11.par~tl.lre a."lU .viud::> Lo.ve ween
obtained and much :no:e accurate date:rm.im. tion:; could be ;,lade if U1Q rock~t trajectories
were more accurately known.
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