Evening star. [volume] (Washington, D.C.) 1854-1972, 1928-08-12

temporary il not permanent soiu-
t4n,, IN nr1e AZ ariafions greatest prom
len1s-tae formation OF ice on alrplanes
is found in report based on . Seuus
~ ice ORGANIZATIONS undertaken by tne
National ADVISORY Committee for Aero
,,srtics at the request Of the Army ana
Navy Air Services. 90
The report, prepared BY Tnonlas Gar
reil and william H. McAvoy ul tne COM
rnittees laboratory stan az Lahglcs
Tsseld and based on information received
S-ovy- scores Of pilots as well as the COM
vnit9ee's own experiments. recommends
ssavcidanee" of the ice formation oy
beinc constantly informed OF the ar
+er1reersf1tre. The dead line" Tor Ice
formation is around 80 degrees Fanren-
heit coupled with certain atmospheric
conditions. ,ue
Information obtained from the large
number Of pilots who have encountered
this ice formation Identifies the conol-
tions. according to the Two e~Pef'S' a.
follows. ,.,.... ,.-,,.,,,,
a condition Of high humidity usually
heavy fog which. more often In the form
IF clouds. either broken cumuilis clouus,
xtrsta formation or a c0noltion 81
sct,IaI rain. must be encountered ~ .
.e,,anersttlre not more than degree or
tao below the freezing point, 81 degIees
Fahrenheit. The formation Of ICE nao
beer reported by some at Temperatures
considerably below 81 degrees Fanren-
1ostf mt these reports. In view OF pre-
,,oyaerancp 81 evidence as well as def
rite experimental data, appear W oe q
. secondary condition which IN lorna :
fioo and in consequence are consioeF-
shiy different from the condition en-
ccgrtered At or near 80 degrees.
Forms Rapidly.
when an sirplsne, according N Car
roll and McAvoy. encounters Fain "
reavv fns at q temperature oi 81 de~
9rees Fahrenheit, minus only one Or
sa,o degrees. the conditions are ideal Tor
the Formation of ice The ice forms
ysnidly and the continuation Of us Tor
nation is dependent only upon the
maintenance Of the conditions, ~lth aii
sInsost certain reduction In flying en-
cheney which results in forced landiiis
within q period OF time which u oIny
dependent upon the prevalence 81 m
conditions probably IN no case ioflgei
than chr gouT III other cases lnFoif :
fpe c0nditi0nS 81 nigh water copLeHl
~ me air 4 temperature JUST be!o#
freezing AMI on already OVERLOADED con
rit5on 81 the airplane lapse % onl}
is or % minutes would be 2uDlcIent y
force tf1c airplane down
Reports from pilots who have col
yecte6 ice on their planes IN genera
agree frst the formation o. ice undei
tfIe fdesI conditions jiis' mentioned ap'
uesrs FIRST upon wires. the for%afe
edge If struts and the leading edge o.
winqs accompanied only slightly lesi
frequently by similar formations On n
leading edge OF the propeller biaddei
and upon The bosses ~ me pfopeDei
arc finally upon the fuSeiage and th'
tai surfaces II Is held highly prob
sbIe that the formation upon the lsl
surfaces ~ almost instantaneous VIII
that upon ghe wings
Prom the reports received Caf{oi
snd MchyoY declare that the iaet ina
To- may form upon the propeller "hn'
inc plane Is In flight is definitely g.
tsbIsened rhe amount 81 ice De
rosi1ed IN the propeller varies IN thick
ness bat il ls certain The experts say
tbst under some conditions u may en-
Vejon not only the blade Up, but ever
As far as u include the propeller DOS
OF spinner where irregular 0epoall
have been observed
Tai Aids Little.
IN lhe fights made boy the Ns'iona
Aevs0rY Committee conditions of
different nature with different coi1sf