Comparison of tail and wing-tip spin-recovery parachutes as determined by tests in the Langley 20-foot free-spinning tunnel

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Material Information

Title:
Comparison of tail and wing-tip spin-recovery parachutes as determined by tests in the Langley 20-foot free-spinning tunnel
Alternate Title:
NACA wartime reports
Physical Description:
25, 27 p. : ; 28 cm.
Language:
English
Creator:
Kamm, Robert W ( Robert William ), 1917-2001
Malvestuto, Frank S
Langley Aeronautical Laboratory
United States -- National Advisory Committee for Aeronautics
Publisher:
Langley Memorial Aeronautical Laboratory
Place of Publication:
Langley Field, VA
Publication Date:

Subjects

Subjects / Keywords:
Parachutes   ( lcsh )
Aerodynamics -- Research   ( lcsh )
Genre:
federal government publication   ( marcgt )
technical report   ( marcgt )
non-fiction   ( marcgt )

Notes

Summary:
Summary: Tests of spin-recovery parachutes on six models of typical fighter and trainer airplanes were conducted in the Langley 20-foot free-spinning tunnel to obtain data for correlating model and full-scale results. Parachutes attached to the tail of the models, to the out wing tip (left wing tip for a right spin), to the inner wing tip, and to both wing tips were tested. The results indicated that parachutes of the same size and type were more effective as spin-recovery devices when they were attached to the outer wing tip in the spin than when they were attached to the tail. The diameter of the outer wing-tip parachute required for a 2-turn recovery by parachute action alone varied from 4 to 7 feet. Parachutes attached to the inner wing tip would not effect recovery. When parachutes attached to both wing tips were used for recovery, the parachute diameters required were of the same order as for tail parachutes. The diameter of the tail parachute required for a 2-turn recovery by parachute action alone varied from 6.5 to 12.5 feet for the airplane designs used.
Bibliography:
Includes bibliographic references (p. 17).
Statement of Responsibility:
by Robert W. Kamm and Frank S. Malvestuto, Jr.
General Note:
"Report no. L-38."
General Note:
"Originally issued March 1946 as Advance Restricted Report L5G19a."
General Note:
"Report date March 1946."
General Note:
"NACA WARTIME REPORTS are reprints of papers originally issued to provide rapid distribution of advance research results to an authorized group requiring them for the war effort. They were previously held under a security status but are now unclassified. Some of these reports were not technically edited. All have been reproduced without change in order to expedite general distribution."

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 003616345
oclc - 71304358
sobekcm - AA00006242_00001
System ID:
AA00006242:00001

Full Text
L_3


NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS





WAlRT IME REPORT
ORIGINALLY ISSUED
March 1946 as
Advance Restricted Report L5G19a

COMPARISON OF TAIL AND WING-TIP SPIN-RECOVERY
PARACHUTES AS DETERMINED BY TESTS IN THE
LANGLEY 20-FOOT FREE-SPINNING TUNNEL
By Robert W. KaTnm and Frank S. Malvestuto, Jr.

Langley Memorial Aeronautical Laboratory
Langley Field, Va.






ty ..... J. *. .-*' *;

*^ ^ ^ "*:"" "*"*'" i" .

WASHINGTON
NACA WARTIME REPORTS are reprints of papers originally issued to provide rapid distribution of
advance research results to an authorized group requiring them for the war effort. They were pre-
viously held under a security status but are now unclassified. Some of these reports were not tech-
nically edited. All have been reproduced without change In order to expedite general distribution.


L-a


VACPA





































Digitized by the Internet Archive
in 2011 with funding from
University of Florida, George A. Smathers Libraries with support from LYRASIS and the Sloan Foundation


http://www.archive.org/details/comparisonoftail001ang




97 1 "



NACA ARR lio. L5',19a RESTRICTED

.!!TIONAL ADVISORY COTG.ITTEE FOR A'F..OiIAUTICS


ADVJA..CE iRESTRIiCTED REPORT


.PARIS..O!' C-F TAIL AI:D V/TIiG-TIP SPII-RZCC' -RY



L:i-GLEY 20-F'oT .RE E-3PI-IG-G fUrI'!EL







Tests of spin-irec Dver-"- s..r :i'ures on si:, '.odels of
typical fighter and trai ner- al.l.lanies wir;:- conu-cted
in the L:argle 20-;Tfot free-si,:.'nnp.; tunInel to obtain
data for correlating. model -andi fuli-scile results.
Parac hutes attached to ce'.-e ta-,l C c -ie models, to the
outer win., tip (left win: tip i or a riMht spin), to the
inner wing tip, and to both 'virn,: tips were tested.

The results vindicated that parachutes of the sar.;e
size and t-ype were ImorCe effe- 1- -.e as s-pil-ri-co'ver:,
devices when che-'r w.i e attache;, to 'thie outer wing- tip
in che spin than when the: wer:e attac he :1 to the- tail.
The dia-neter of che aLter t wing-ti p para,:r'-.ute required
for a 2-turn recover:- o; parachute action 9loc-ie varied
from L to 7 feet. Parachutes a;tac'.-:d to the inner
win,; tip would not effect recovery. When paracl-hutes
attache-- to both winY tips were us,d. fior recovery, the
parachute diameters required were ,of the s &me order as
for tail parachutes. The dinaeter of the tail parachute
required for a 2-turn recovery by a.rachnte action alone
varied from 6.5 to 12.5 feet f'or the airplane designs
used.


II'ITRODUC 2i1II


In order to obtain data for a correlation between
model and flight tsts of spin-recovery parachutes, tests
were conducted with six airplane models of single-engine
design. The effectiveness of both tail and wing-tip
parachutes as spin-recovery devices was determined for
these models. The spin-recovery parachute is normally









2 NACA ARR No. L5G19a


used only as a ternPcrary emergency safety device during
spin demonstrations so that rapid recoveries from
uncontrollable spins may be obtained. Available flight
and model test data on the use of tail parachutes as
s'in-recovery devices are presented in reference 1, and
the results of these tests indicated that airplanes
weighing between 7500 and 14,000 pounds require tail
parachutes having diameters of approximately 8 feet
(based on a drag coefficient of 1.02) and towline
lengths between 20 and 50 feet in order to obtain
satisfactory recoveries by the use of the parachutes
alone.

Results are Dresente.? herein of the investi-ation
of the six airplane models, designated models A, B, C,
D, E, and F, with spin-recovery parachutes attached
either to the tail or to the wing tips of the models
for the normal loading conditions. On each model, tail
and wing-tip parachutes of various sizes were tested with
several lengths of line cornmecting the parachute to the
airplane. The results are analyzed to show the minimum
satisfactory size of the parach2te and the optimum length
of the towline for spin-recovery-parachute installations.
Brief additional tests were conducted to investigate the
effect of mass variations on the effectiveness of the
spin-recovery parachutes when attached to the win; and
the effect on recovery of simultaneously opening a tail
parachute and neutralizing the ru"'er. For one model,
tests were made at two equivalent spin altitudes to
determine whether altitude critically affected tail or
wing-tip-parachute effectiveness.

Two of the models (A and B) had been used in the
investigation of tail parachutes reported in reference 1
and tests of tail parachutes were accordingly not repeated
for these two models. The results obtained in the
previous investigation are included however in the present
paper.

S3 .:-OLS


b wing span, feet

m mass of air-la-ie, slugs

IX, Iy, and IZ moments of inertia about the X, Y, and
Z body axes, respectively, slug-feet











Iv I
-i--- iinertia yawing-iroment -are r.eter
mb

Iy I
2 inertia.rolling-moment Daranmeter
mb2

I1 IX
-b2 inertia pitching-:iorent .iarameter
mb2

a acute an'le between ve-rtical a-xis an-d th-rust
line (aprro,: L: t.--: .equal Lo absolute
value of anrl:le c- attackk at lane of
s :rJe try), degreeses

J$ angle betvr..e san miss -:d hiorizont; ,
de.rre as

V airnplane crue rate of descent (estimated
b-y scaling ircon romdel v-alues), feet
per second

aQ rair-lans ang ular velocity- about s-in axis
(esti:vmted by scaling from model values),
radians per second

D dr.ag of parachu'te, pounds; also diameter of
n-arachlute scre-i .'lat

q ,ynaetic nreasure I-;P I

p a-r density, slugs ner 3bLiic ftot

CD drs3 ccefficient of Tar-alchute (

S surface are-a of parachute,-square feet
L \
CZ rolling-moment coefficient I-

S wins area, square feet

L rolling .omrent about longitudinal.body axis,
foot-ryounds
Cn yawing-a.oment coefficient

N yawing moment about normal body axis,
foot-pounds








NACA ARR No. L5Gl9a


APPARATUS ANZD MODELS


The tests were performed in the Langley 20-foot
free-spinning tunnel, the operation of which is similar
to that of the 15-foot free-spinning tunnel described
in reference 2.

Models A, B, C, and D, used in the investigation,
represented typical fighter airplanes, whereas models E
and F represented typical trainer-type airplanes. The
design characteristics of the airplanes represented by
the models are presented briefly in table I and three-
view drawings of the models used in the tests in the
Langley 20-foot free-spinning tunnel are presented as
figures 1 to 6.

The general construction of the spin models is
described in reference 2. Briefly, the models, con-
structed of balsa, are dimensionally representative of
the corresponding airplane and are ballasted for
dynamic similarity to the corresponding airplane by the
installation of proper-size lead weights at suitable
locations.

The model parachutes used for most of the tests were
the same ones used for the investigation reported in
reference 1 and were made of parachute silk. The skirts
of these parachutes were not hemmed, nor were the para-
chutes made of individual panels. They were circular
and when spread out on a flat surface formed a disk.
Circular vent openings were cut in the center of the
parachutes and were made one-twelfth of the diameter of
the parachute when spread out on a flat surface in order
to simulate approximately full-scale vent openings.
Eight shroud lines of equal length were evenly spaced on
the periphery of the parachute. The shroud-line lengths
were made 1.35 times the diameter of the parachute
because it has previously been found (reference 3) that
with shroud lines greater than 1.25 times the diameter,
the drag coefficient varies only slightly with change
in shroud-line length.

In order to determine whether details of construc-
tion affected the action of the parachutes, a few
parachutes were constructed to simulate more nearly
full-scale parachutes that is, the skirts were hemmed








NACA ARk Ho. L5G19a


and i'-e parachutes -;ere made of individual panels sewed
together (fig. 7). Ten panels and ten shroud lines were
arbitrarily used for these parachutes.





The spin--cesting technique used in the Lancle;. free-
siinning tunnels is described in detail in reference 2.
Briefly the nrodels with tihe rudjer set for the nsin are
launched-. by ha-nd (this procedure s.upersdes the launching-
spindle method discriob-e in reference 2) in a spiining
attitude into th': vertical up.a'rd air scream of the
tunnel. Tn- air.s3r. ed is d .s -?id to eqiual ;, e n:jrral
rate of descen.'-,t cIf the ,-o3de. A .e;r'o.-cotrol mechanism
is installed in t'-,e rmodzls to actu..te C-.e controls cr to
release the -arac-hute for r.ecove-"ry atten'"pts.

For tests i d-i. thE parachute mnountiid at the tail,
most recoveries w'-re attem'"ited '-7 e.; ~cing the parachute
frnri a contain ner ( s : scrib.c in. reference 1). The
rud-er was heot vith t'e spin dur.lis recover" so that
the ef.ft-ctiv-wness of the rs:-a.chute aloni could be obtained.
In adj -1tion, a nu-i.-iIer of t.'sts w. ,-E con; uctei in abl ich,
for recovery, the rudder Iwa e iae'.ic.-l iz..d at LWe sr'e time
that the ipa:'.chute was opened so th!.t t}-e cDintinld effect
of o!pe:-.ncS thn parachute and neutralizing the rudder could
be evaluated.

Fo:' c;".e investigation of win:-tip parachutes, the
parachu les w.;ere rni-tfted~ on thie u:p.",r sr-face cf Ithe .ing
near :.he "in tip. Fi.u.re 3 show'3 the u.e of ir-tal-
lat-on us.-.d. Fc' attct p-:ted recovsries, a rub:.e bind
hol.dinr': ?ii acked, model parachute to .:he ncr. '..as
released '.:.:i the reircte-control j ne-'iihanisi andi tl-Ce parachute
was ct.':f.ed mcrel '' b: the action of the air s3re-am over
the ,ing.

Tests .,'ere made to determine ithe parachute effec-
tivenes.: with the loading along :he wings and along the
fusel--;e varied for several of !r-e models. Table II
presents the mass parameters of the models for the
normal clading condition and for the alternate loading
I Iy Iy I.,
conditi ons. The parameters ,
I? IX m2 mb2
and ab2 are indicative of the relative distribu-
mbon of te mass alone the three bod axes.
t.'on of the mass along the three body axes.








NACA ARR No. L5Gl9a


As previously mentioned, tests of both tail and
wing-tip parachutes were made for one model ballasted
to represent the corresponding airplane at altitudes
of 10,000 and 20,000 feet.


RESULTS AND PRECISION


The results of the investigation are summarized in
tables III to VIII and figures 9 to 27,

The drag coefficients of the model parachutes were
found to be approximately 0.75 (based on flat area) by
determining in the tunnel the rates of descent of the
freely falling model parachutes with various weights
attached. The full-scale-parachute diameters referred
to herein were obtained by scaling up the model values,
inasmuch as at the present time only limited data are
available on the correct value of the drag coefficients
of freely falling full-scale parachutes. Reference 5
indicates that the drag coefficient 0.73 obtained for
model parachutes is within the range of values of drag
coefficients 0.62 to 0.79 obtained for freely falling
full-scale silk antispin parachutes. In reference 1,
the parachute diameters were corrected for a difference
in drag coefficient between model and full-scale para-
chutes on the assumption that the drag coefficient of
full-scale parachutes was 1.02. In order to select
the full-scale parachute, it is therefore necessary to
know the drag coefficient of the full-scale parachute
and to correct the parachute diameter for any difference
in drag coefficient between the full-scale parachute and
the model parachute to obtain the same drag. An example
showing the method used to determine the correct diameter
for full-scale parachutes, based on drag coefficients of
model parachutes, is given in the appendix.

The parameters given in table III present the steady-
spin characteristics of the models just prior to attempted
recoveries. All the models used in the present investiga-
tion had previously been tested and repaired extensively.
As a result, the steady-spin characteristics presented in
table III are somewhat different from those obtained
during the previous routine investigations of the models
but are considered to be accurate enough to give depend-
able results for the present investigation.







NACA ARR No. L5G19a


r'-e stea;d-snin psrarr ters presented in table ITT
are -eliev-d to ,c the r" values tiven h- the model
within -h following limits:

, d re . . 1
r, perc ene . .
, percent . . .
I pe r ce.-,t . . +2

oszt of c. e rScojm .r--' ,i tu: r t-cd ii :--he fi ,ures
were ot'.taind frc': fib-. i'eccrds ancd re believ-i tc
I + 1
be the true values ,'vn by the ,'iod s withini n +- turn.
A few of The rec .--e.rie s vJw e obsc, ) n..i-il ;:-- visual esti-,.ites
and are believed to be s:_ul'rt ..ithin tiin.

D IS:;- U s : ri~.,]i

Para .hu.te C instructionn


The res;,.ts of0 brief tc;ts thcat ..iee cornuct:i to
com-rpare the drag coefficlenca a-nd e- fe ctiv:cr.e ss cif the
Dlaifn fabricated model parachutes u:.sed in ti-e investi a-
uion rerfortd i re erence 1 ith :,he d rag co ffic ints
and effectiveness of narachutes mi.ore ::early a'rcx if.,auifg
full-scale constr-.ction, as shon in fi.s'hur.e 7, sho'.ed
that the .ira'1 coefficients of .e c ifferentl- con stru Le3
parachtu.tes wv.;-re similar and that :-i-e r& arachutes hld the
sai:e effectiveness ofo o':eration Lurin. .:iodel tests. :'ost
of the tests we ve therefore conducted 'ith the olain
fabricated parachutes sinLce c-'."se pareachuts wier r adil-
available in all sizes.


Tail Par-ac ..tes

The vai'iaticn of turns -or recover-- ..1th tail-
narachute diameter fo r the norim al-control con;fiiguration
for sp.nnnin (ru:t.:er full ..a ,th t.? s-,in, elevator full
up, and ailcroin:s neutral), Lcr t e elevator-neutral
position (ailerons neutra;l), ar-d for rt.,e elevator-down
position (-ailerons n-eitrlal) aire pressnted in *i:.ures 7,
10, and 11, respectively. Feccv.-rios were attempted by
ejectin, t'-e parachute from a cylinder installed near
the call. In 'iures 9, 10, 11, and the follow-ng
gr-aphs, the arrows on the ends of some of the curves








NACA ARR No. L5Gl9a


mean that the model did not recover in the number of
turns indicated. Parts of the curves falling between
points representing a diameter that gave recovery and
one that did not give recovery are dashed to indicate
that the fairing of that part of the curve is
questionable.

For a constant towline length the turns for recovery
generally decreased as the tail-parachute diameter
increased. The approximate full-scale-parachute diaLmeters
required to effect a recovery from the spin in 2 turns at
the normal-control configuration are summarized in
table IV and varied from 6.5 to 12.5 feet.

For models A B, ,and C, spins with the elevator up
required somewhat larger tail parachutes than did spins
with the elevator neutral or down, whereas for models D,
E, and F, the opposite was true (figs. 9 to 11).
The explanation of this result is not apparent.

The length of the towline of tail parachutes had
a marked effect on the number of turns for recovery, as
may be observed from figure 12, which presents results
for elevator-up spins. (Although not presented, the
same type results were obtained 'ith the elevator
neutral or down.) Towline lengths between 20 and
50 feet full scale were most satisfactory because
within these limits the variation of turns for recovery
with towline length was small. This result is con-
sistent with the conclusion of reference 1.

The effect of simultaneously opening a tail
parachute and neutralizing the rudder is presented in
table V for the up, neutral, and down positions of the
elevator (ailerons neutral). Neutralizing the rudder
in conjunction with opening the parachute was somewhat
beneficial for all conditions tested.

As previously mentioned, reference 1 indicates
that an 8-foot tail parachute (based on a drag coef-
ficient of 0.73 instead of 1.02, the diameter of the
parachute would be 91 feet instead of 3 feet) would
effect a satisfactory (2-turn) recovery from the
steady spin for airplanes weighing between 7500 and
14.,000 pounds. 7_I. current tests indicate that the
diameter of the tail parachute required for a satis-
factory recovery from the spin is not constant nor








"ACA ARR HJo. L5G19a


does it vary directly ,.titih :he weight of the .- rplar e.
For example, a.rrilane C havir: a gross 'iei-xht of
740'6 rpo'.ucds requ.irei a 'F-foo-t tail parachute and air-
plane L. hiavin a gross weight of .'-011 pounds required a
12.5-foot tail parachute, but airplane P having a gr;oss
weight of c277 pounds (121 -, -,unds more -than the tross
weight of airpl ane D) relui;red. a 9-f ,lot parac-huce for
satisfactor'-- recovery- fro:i th3 spin.


lParachutes mountedd on 'ute' .in: Tin

'The wing-trp par'achute.li s, iaer tioc.nE,'i d :or-e vio'usly, 'w.ere
moiuniited on the' uri-er surface ., cl-e win:; rinea the wine
tip, as shown in fi luue D. In some cases, ICthe protub.erance
of the packed :arachu,.te af c c cited te3 .teady spin o, the
model, and for each series of reasta determination of the
location at which to p:lac-. the narachlute -acl-;: wvas necessary
so that i-he stead--s.in charac teristic of th'e imod.el v.ere
not chang.d. For t-hi- C.son, i-installing the parachutes
on the surface c: the wing of airplanes is not considered
advisable. The i rar-a.~hu.te packs should instead 1-: placed
inside t-Lie win M and provision should be iiad.e to eject
the parachutes into the air stream.

The variation of turns for' recover:' with parachute
diameter :or ;arachutes r.ounted cn the outer wing tip
(left wing tip in a right spin) for spins with the
elevator up,, neutral, and down are presented in fig-
ures 1,', 14, and 15, respectively. f1 i .ure 16 shows the
action of ,:he outer wing-tip parachute in effecting a
recovery' froni the spin. The towline lengths were
generally m!-ade approximratelrT equal to the semiispan of
the airplanes. In general, for all ;-iodels a larger wing-
tip parachute was required to effect recovery from spins
with thie elevator n,-utral or 'r.vown ther' .tr'rom spins .LiSth
the elevator up. The diazeters of th-e outer wing-tip
parachutes required to effect a recovery in 2 turns from
the spin at the normal control confi u.ration for spinning
are .given in table IV for all the models and varied
from 4 to 7 feet.

The results in table IV indicate that for the models
tested, a parachute attached to The outer wing tip is
more effective as a spin-recovery device than the same
size racachute attached to the tail.








NACA ARR :Io. L5G19a


Figure 17 presents test results showing the vari-
ation of turns for recovery with towline length for
wing-tip parachutes for the elevator-up spins. Towline
length did not appear to influence the effectiveness of
the parachutes appreciably. .hen no towline was used
(or when the towline was very short), however, the
parachutes sometimes fluttered in the wake of the win-
as shown in figure 18 (frames 14 and 15) and did not
function properly. If long towlines (towlines approxi-
mately equal to or greater than wing span) are used to
attach the parachute to the wing tip, there is the
possibility of the parachute and towline fouling the
tail or fuselage of the airplane as shown in figure 19
(frames 5 and 4 ). It is recorumended, therefore, that
the length of the towlines be such that when fully
extended the parachute just -misses both the tail and the
fuselage.


Parachutes counted on Inner Wing Tip

Brief tests (test results not presented) made with
parachutes attached to the inner wing tip (right wing
tip in a right spin) indicated that parachutes on the
inner wing tip will not effect a satisfactory recovery
from the spin. For some cases use of the parachutes
was observed to flatten the spin. It is, therefore,
very important to use care in opening the correct wing-
tip parachute for attempted recoveries from spins.


Parachutes countedd on Both /ing Tips

The simultaneous opening of two identical parachutes,
one mounted on each wing tip, would eliminate the hazards
encountered in using only one 'ing-tip parachute the
hazards are the possibility of opening the wrong parachute
or the c.ar-er of being forced into a spin in the opposite
direction by a large wing-tip parachute (see fig. 20) if
the parachute is not released immediately after recovery.
The effect of parachute diameter for elevator-up, elevator-
neutral, and elevator-down spins on turns for recovery
attempted '. simultaneously opening parachutes on both
wing tips is presented in fi2-irs 21, 22, and 25,
respectively. Satisfactory recoveries frc:i the elevator-
up spins could not be effected for models A, B, E, and F
with the largest parachutes tested. The results for models B,
E, and F were not plotted because, for the size of the








NACA ARR Ho. L5G19a


parachutes investigated, recoveries could not be obtained
from snins. Models C and D required, approximately 8-foot
parachutes for a 2-turn recovery. The results presented
in figures 21 to 23 indicate that moving the elevator
full down in conjunction with opening the parachutes
may be desirable in order to obtain recovery from spins
by simultaneously opening parachutes .-ounted on both
wing tips.

A comparison of the results presented in table IV
shows that much larger parachutes will be required to
obtain satisfactory recoveries by opening parachutes
mounted on both wing tips than by opening one parachute
mounted on the outer wing tip. In order to obtain
satisfactory recoveries by openinL parachutes fastened
to each .ing tip, th'e parachute diamleters tmav have to be
as large or larger than the diameter for tail -parachutes.

Figure 2L shoas the eff-ect of towline length on
turns for recovery attempted by the use of parachutes
mounted on both Wingf ti;s for th3 elevator-down condi-
tion. AS was the case for parachutes Imounted on the
outer wing tip, towline length generally had little
effect on turns for recovery. When the towlines were
too long (equal to the span), however, they frequently
became tangled with each other and did not effect
recover;.. The results presented in .figure 2.4 are for
the cases in which the parachutes opened properly with-
out tangling.


Loading Variations

In order to determine whether variations in loading
of the models would influence the effectiveness of
parachutes, tests were made on some of the models with
the loading varied along the wings and fuselage.

Brief tests of outer wing-tip parachutes were made
on four of the models with the loading along the wings
increased and on one of these four models with the
loading along the fuselage increased. The results,
which are su.imarized in table VI, indicate that extreme
increases in the loading along the wings had little
effect on the recoveries obtained by opening parachutes
fastened to the outer wing tip for models A and E but
had an adverse effect for models C and F. A moderate
increase in the loading along the fuselage had little
effect on recoveries of model F.








12 1--.3A ARR No. L5Gl9a


Table VII sumwmarizes the effect of loading vari-
ations on the recoveries obtained by simultaneously
opening :'arachutes mounted on both wing tips for models 0,
E, and F. -ith the loading along the wings increased
for model C, recoveries were slower than for the normal
loading condition. As mentioned previously, recoveries
could not be effected for models E and F in their normal
loading conditions, and increasing the loading along the
wings of these models had no noticeable effect on recovery.
A moderate increase in loading along the fuselage had no
appreciable effect on the recoveries of model F.

Brief tests were made with model B to determine the
effect of loading variations on recoveries attempted by
simultaneously opening a tail parachute and neutralizing
the rudder. The results are presented in table VIII and
show that moderate increases or decreases of mass along
the fuselage and wings did not appreciably affect the
recoveries.


Effect of Test Altitude

Brief tests were conducted with model E to determine
whether variations in test altitude would influence the
effectiveness of spin-recovery parachutes for this air-
plane. The model was tested at simulated test altitudes
of 10,000 and 20,000 feet. T.e results are presented
in figures 25 to 27. Based on these meaer results,
there ap pears to be little effect of altitude on the
optimum size of wing-tip or tail parachute required for
satisfactory recovery. T1-. test altitude also had
little effect on the variation of turns for recovery
with towline length for parachutes attached to the tail.


Action of Spin-Recovery Parachutes

Tail parachutes.- The action of tail parachutes in
effecting recoveries from spins has been discussed in
reference 1. Briefly, with long towlines (towlines
longer than 50 feet, full scale) the parachLte towlines
tend to incline tow-,-A the spin axis. With short tow-
lines (less than 20 feet, full scale) the parachute
towlines tend to remain alined with the fuselage axis.
With towlines between 20 and 50 feet long, the parachutes
usually ride aporcx:-;ately over the tail of the model,
although they m.-y oscillate from this position.









NACA ARR No. L5Gl9a 15


efe rnc3 1 indicates that as the towline may usually
incline away :rom the plane of symmetry toward the inner
.i!-j) tirt, the parachute e:zerts yawing as well as pitching
mcments rout tnat the effectiveness of the parachute
results more f-rom the antispin yawing r.o.nent than from
the pitching moment produced.

Outer ,wing-tip parachutes.- The typical action of
a parachurte fastened to the c.uter wing tip in effecting
recoverV is shown in figure 16. Frame 15 of fi ure 16
and frnes 22 a.id 34 of figure 19 show that the parachute
towline tended to incline a;a- .. r-o:i the fuselage axis
toward the vertical axis. Frame 20 of figure 16 and
frames 16 and 2o of figure 19 show that the parachute
towline generally tended to rina.r parallel to the
X-Z lane of the model, altho-.u'`h the parachute did
oscillaCe. Thm :iotion-picture records of all the tests
indicate that both rolling and yawing moments were set
up by rte :'arachute. As a matter of interest, the esti-
mated yawing and rolling mor..ents con'-ribut d by parachutes
were cor:oared .it correspond i;. mo,-ients contri'~ited d b
rudder reversal ,-nd full ailer.on deflection. The no;ienits
resulting from, ru c!er and aileron deflection were computed
by use of ._-verags m~en:nt-coefficient values for angles
of attack' in t:;e spiniu-ng range obtained from force tests
on models of other airplanes. For c.ises in wv-lici the
outer wing-tip parachute was effective, -e ro-ling-
mo'-nent ccafficient Ci due to the parachute was in the
direction to roll the m''*odie into the spin and varied
from 0.010 to 0.015, v.which issless thjS one-half the
typical rolling-.noment coefficient of 0.03 developed by
full aileron deflection. The yawing-mcoment coeffi-
cient Cn due to the parachute was appro:-:> i.ately equal
to te typical yawv;.-.-or:eb ccef'ficient of 0.0C15, which
w-ould -be e.:rected from full reversal of the rudder.
The effectiveness of .ing-tip r. .rachutes a._ecrs to
res-.lt therefore more fr.r. c:h ? awin, m.iiments set up
by the parachute than front the :ollling racments.

Reference 1 states tha: when the mass of an air-
Dlane is distributed ctie.fl:' alo':-,. tne fuselage, setting
he ailerons .'" ith t.he spin 1.1i assist recoveries
obtained b7 rudder re-;ersal, whereas -!-.en the mass is
ris ributed chiefly along- t-e wing, -etting the ailerons
with the spin may greatly retard recoveries. A parachute
*attached to the o-:ter winr,g tip, by inducing a pro-spin
rolling moment, is in ef'fct siLwniu;t.in the Aileron-
a;ith-snin configulatioii of the airplane. It would be








NACA ARR No. L5G19a


expected, therefore, that recoveries obtained by the use
of an outer wing-tip parachute would be retarded by
extending mass along the wing of the airplane, if the
yawing moment due to the parachute and the yawing moment
due to rudder reversal are approximately equal. This
adverse effect of extending mass along the wing was
obtained for models C and F, whereas for -;odels A and E
very little effect on turns for recovery was obtained by
change in distribution of mass.


CONCLUSIONS


Results of tests of spin-recovery parachutes made
on six models of typical fiEhter and trainer airplanes
to obtain data for correlating model and full-scale
results indicatedthe following conclusions:

1. Parachutes were more effective as spin-recovery
devices when they were attached to the outer wing tip
in the spin than when they were attached to the tail,
The diameter of the tail parachute required for a 2-turn
recovery by parachute action alone varied from 6.5 to
12.5 feet, whereas the diameter of the outer wing-tip
parachute required for a 2-turn r-ecovery- by-parachute
action alone- varied. from-l. to 7 feet.

2. When a parachnue. a-~tached to the inner wing tip
in the spin was opened, the parachute- would not effect
recovery.

3. -"'hen parachutes attached to both widng tips were
used, the parachute d- maters required were approximately
the same size as for tail -nziz achates.

4. For wing-tip parachutes it is recommended that
the towline length be .such that -hen fully extended the
paraachute jus-t rises both the tail and-fuselage.

5. For tail pa-~-ab -&s the towline should be
between 2- and 50 feet long.

6. Neutrtalizing the--rudder at the same time that
the tail parachute was opened gave faster recoveries
than- were -obtained b- -opening the cpracbute alone,








:TACA ARR io. L5G9la 15


7. For two of che four models ;ested .'ith varied
mass distribution, extension cf ntess alon" chs wirng.3
had an adverse effect on re ccveries acempted by Opening
parachutes attached to the outer wing tip.

3. Tests conducted with one model at two equivalent
test altitudes (10,CuO and 2C, ju ft) shca-ed no ncticeable
effect of a change in altitude on the op,:;.ium' size of
wing-Lip or tail parachute required for satisfactory
recovery.


Langley Y.e.:.orial Aeronautical Labora:ory
National Advisory Co.n.ittee for Aeronautics
Langley Field, Va.








NACA ARR No. L5Gl9a


APPENDIX


Ei--OD OF CO=L ECTI-NG PARACHUTE SIZE FOR DIFFEE:CES

IN DRAG COEFFICIENTS


The model tests indicate that for model C, for
example, a 9.0-foot parachute fastened to the tail
will be required to effect a recovery in 2 turns by
merely opening the parachute. This diameter is based
on a drag coefficient CD of 0.75 for the parachute.
If it is planned to use a parachute of similar shape
but of different material so that the parachute has a
drag coefficient of 0.56, the area must be larger in
the ratio of 0.75/0.56. The parachute diameter must
therefore be larger in the ratio =1 l.4, which
V 0.56
gives a parachute diameter of 10.5 feet.







NACA ARR Ho. L5G19a


REFEREC ES


1. Seidman, Oscar, and Kamm, Robert A.: Antispin-Tail-
Parachute Installations. IACA RB, Feb. 1935.

2. Zirmierman, C. H.: Preliminary Tests in the N.A.C.A.
Free-Spinning Wind Tunnel. iTACA Rep. Ho. 557,
1956.

5. 'ood, John H.: Determination of Towline Tension and
Stability of Spin-Recover- Parachutes. NACA A-R
No. L6A15, 1946.

4. Neihouse, A. I.: A Mass-Distr'iution Criterion for
Predicting the Effect of Control M:anipDulation on
the Recovery from a Spin. MACA AP., Aug. 1912.










NACA ARR No. L5G19a


rl
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L9 NACA ARR No. L5G19a

TABLE II

MASS PARAMETERS OF MODELS TESTED FOR NORMAL AND
ALTERNATE LOADING CONDITIONS


IX Iy Iy IZ Iz -. I
Airplane Loading condition 2 --
ab2 mb2 mb2


Normal


IX and Iz increased
50 percent IX


Normal

Normal


Iz increased
percent IX


A

A


B

C

C


D

E

E


F

F


F


Normal

Iy and IZ increased
50 percent Iy

IX and IZ increased
124 percent IX


14 x 10-

125


-6

-43

173

-67

-63


170


-64


-210 x 10"4

-525


-163

-160


-389

-121

-90


-323


-62


-206


196 x 10-4

200


169

203

216


188

153

153


126

182



124


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS


IX and
115


Iz increased
percent IX


Normal

Normal


IX and
206






NACA ARR No. L5G19a 20

TABLE III
STEADY-SPIN CHARACTERISTICS OF MODELS JUST PRIOR TO ATTEMPTED RECOVERIES

[Controls set at ailerons neutral, rudder with the spiu

Rudder Elevator
Airplane Loading deflec- deflec- a V J
condition tion tion (dog) (deg) (fpa) (radians/sec)
(deg) (deg) (a)

A Normal 30 30 up 41 2d 226 2.7
A Normal 30 0 39 3d 214 3.2
A Normal 30 20 down 38 4d 207 3.4
IX and IZ
A increased 30 0 40 2u 172 3.4
50 percent IX
B Normal 30 30 up 6 2d 239 2.3
B Normal 30 0 38 D 226 3.1
B Normal 30 20 down 34 lu 222 3.3
C Normal 0o 55 up 42 1d 203 3.6
C Normal 30 0 52 1d 171 4.2
C Normal 50 15 down 51 ld 164 4.2
D Normal 30 50 up 55 lu 197 2.7
D Normal 30 0 53 3u 184 2.9
D Normal 30 20 down 54 lu 177 5.0
E Normal 35 25 up 41 3d 147 2.4
E Normal 35 0 45 6d 125 3.2
E Normal 5 25 down 41 8d 125 5.5
IX and IZ
E increased 35 25 up 21 3u 217 3.5
206 percent Ix
P Normal 35 30 up 36 4u 178 3.6
F Normal 35 0 35 lu 162 3.7
SNormal 35 20 down 36 3d 147 2.4

IX and IZ
F Increased 35 20 up 26 3u 167 3.0
124 percent Ix
ly and IZ
F Increased 35 20 up 38 0 172 2.3
50 percent Iy

aIn describing 0, u means inner wing upS d, inner wing down.


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS





NACA ARR No. L5G19a


TABLE IV

FULL-SCALE PARACHUTE DIAMETERS REQUIRED FOR VARIOUS
LOCATIONS OF PARACHUTE INSTALLATIONS TO

EFFECT RECOVERY FROM THE NORMAL-
CONTROL-CONFIGURATION SPIN IN

2 TURNS BY OPENING

THE PARACHUTES



Approximate diameters (ft)
required with:
Model Parachute Parachute Parachute
fastened to fastened to fastened to
tail outer wing both wing
tip tips


A 10.0 5 >7

B 9.0 7 >9

c 9.0 5 9.0
D 12.5 5 8

E 6.5 4 >6.5
F 9.0 5 >6


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS







NACA ARR No. L5G19a


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SNACA ARR No. L5G19a

TABLE VI

EFFECT OF LOADING VARIATIONS ON TURNS FOR RECOVERY OBTAINED BY OPENING
A PARACHUTE MOUNTED ON THE OUTER WING TIP

[Controls set at ailerons neutral, rudder with the spin]

Full-scale Full-scale Turns for recovery
Airplane Loading parachute towline Elevator
conditions diameter length Elevator up Elevator down
(ft) (ft) (a) neutral (a)


A Normal 7.0
IX and Iz
A increased by 7.0
50 percent IX
C Normal 5.0

Ix and Ig
C increased by 5.0
115 percent IX
C Normal 7.0

IX and 1z
C increased by 7.0
115 percent IX

C ------do------ 8.8

E Normal 5.6

x and IZ
E increased by 5.6
206 percent IX

F Normal 5.0

Ix and Iz
F increased by 5.0
124 percent IX

F -------do ----- 6.5

ly and IZ
F increased by 6.5
30 percent I
aThe values of the deflections


10.0


10.0

17.0


17.0

17.0


17.0

17.0

17.3


17.3


15.8


15.8


15.8


15.8


1 01


1- to 2
2


1r

More


1i


1 to 1


to 2

2


than 4 ------- ----


1
2 to 1

1= to 2

1 to
2











More than 6


1

1
2


I to
1 to 12


1 1
I6 to I


to 2


1
1 to .1


1 to I


1 to 1
4.


of the elevator and rudder are given in table III.


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS


-----***--------


1










4







NACA ARR No. L5G19a


TABLE VII

EFFECT OF LOADING VARIATIONS ON TURNS FOR RECOVERY OBTAINED BY SIMULTANLOUSLY
OPENING IDENTICAL PARACHUTES MOUNTED ON BOTH WING TIPS

[controls set at ailerons neutral, rudder with the spLn]


Pull-scale Pull-soale Turns for recovery
Loading parachute towline
Airplane conditions diameter length Elevator up Elevator evao
(ft) (ft) (a) neutral (a)


Normal

I and IZ
increased by
115 percent IX

Normal


IX and I
increased by
115 percent IX

Normal

Ix and Ig
Increased by
206 percent IX

Normal

Ix and IZ
increased by
124 percent I

Normal

IX and IZ
increased by
124 percent Ix

ly and 12
Increased by
30 percent Iy


7.0



7.0


8.8



8.8


5.6


5.6


5.0



5.0


6.5


6.5



6.5


68.0



68.0


17.0



17.0


34.6


54.6


15.8



15.8


15.8


15.8



15.8


1 to



More than 4


*to 1



1 to 2



o0

00




00




More than 6

o00



More than 4


2 toe 2






1



















1





Slto


2, 5. 2













l-- 2--
1












1







4


aThe values of the elevator and rudder deflections are given in table III.


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS







NACA ARR No. L5G19a


A

a m


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NACA ARR No. L5G19a


.24-
.24-


Thrust line


hinge


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS


Figure 1.- Drawing of model A used in the tests in the Langley 20-foot
free-spinning tunnel. Normal loading condition.


Fig. 1





NACA ARR No. L5G19a


elevator hinge


rudder hinge


NATIONAL ADVISORY
COMMITTEE 7OR AERONAUTICS


Figure 2.- Drawing of model B used in the tests In the Langley 20-foot
free-spinning tunnel. Normal loading condition.


Thrust line


Fig. 2






NACA ARR No. L5G19a


4 "at30% chord -


Thrust
line


NATIONAL ADVISORY
COMNITTIL FOR AEONAUTICS


Fire 3.- DraIng or mo.jel C usea in the tests in the Langley 2?-fcct
free-sBpnninT tunnel. Normal loading condition.


Fig. 3





NACA ARR No. L5G19a


Se/ei'ator


Fuse/age refer
//;7e
NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS


/incidence


Figure 4.- Drawing of model D used in the tests in the Langley 20-foot
free-spinning tunnel. Normal loading condition.


Fig. 4








NACA ARR No.' L5G19a


NATIONAL ADVISORY
COMMITTEE rot AERONAUTICS


Figure 5.- Drawing of model E used in the tested In the Langley 20-foot
free-spinning tunnel. Normal loading condition.


Fig. 5





NACA'ARR No. L5G19a


I elevator hi,


! aileron hnge
I--,/


Fuselage reference
line --7 .3,


Thrust


rudder hinge


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTlCS


Figure 6.- Drawing of model F used in the tests in the Langley 20-foot
free-spinning tunnel. Normal loading condition.


Fig. 6









NACA ARR No. L5G19a


Fig. 7a,b


0

OrO
3








0 0
-Ci


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NACA ARR No. L50G19a Fig. 8























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NACA ARR No. L5G19a Fig. 9











i n






/ -


----- --- f

uO
,_ s

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------- I s "
04 z











q,
-- -_ / ,.\ i.U.
--- -- -- -:_ --- -- -- -- -- --- -- --- ----- ,S










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Fig. 10 NACA ARR No. L5G19a








----------------------------------------------------r~----- '
_____-------------- a- .



"2-









I-2I
_1
____ ___ ___ ___ ___ ___ ___ __ __A l W ------^ ''





,q) t_ 3









__---aA------------ -- s-
14-----------------------------------------4---------- \ *












_
__ _' N \ ,





NACA ARR No. L5G19a Fig. 11






I q
---- -- ---- -- .N

Nj
a'














Z'. eAooa aot ru-In.L
_____-__-__ --_ ___



b-- ^


~ ~ ~~ ~o ~ ~w~ JO] .S^U




NACA ARR No. L5G19a


8

3
f
I
e


2 20 40 60 80 /00
FA/l-sca/e tow//m7e /e/fyth, ft
F/~(-/re/2.-7Te variacf/on of /ar's for recovery
w;fh tow/ine /eny/IA; recovery aitfem/ ed
hy op/qe,7y toa// rachcue. Contro/s set at
/rucdder w/ith'f, a//era2y-7 eu/ra/ e/evaor i4-


Fig. 12






NACA ARR No. L5G19a


3




2


3 4 5 6 7 9
Fu//-scale cd/kce/er sca/ed up from model size, ft
F/'yure/3J.-The var/af'/on of furf/s for recovery w/th
w/fy-fy-/perac7cA/e da/me/er; recovery a fempt ed
by c)er/o pear/cA/e m/iewo/ed on or er wi,,y to.
Co-,/to/s ef / ar /dder/ wi/, ai/eron,/s e trfa/1
e/eva/or /p.


Fig. 13





NACA ARR No. L5G19a


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS
4 5 6 7 5 9
Fu//-soa/e odiaee fer s~a/ed up from mode/ s/ze, ft
Fayre I-rThe vari/a/on of fArns for recovery w/t/f
w/7zy-- f//-parac/Ae d/o'reft er recovery atf'empfed
by opetn/,9 parca/)e mounted on outer w/9g //o.
Ca7t/ro/s s etof rudder w//h, a//ero/as nea ra/,
e/er yor neufral/.


Fig. 14






NACA ARP No. L5G19a


5




4


Q\
K3



2



/


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS


4 5 6 7 8 9
u//--sca/e d~/ame fer sc/ed urp from mode/ s/re, ft
F/g9ure/,.-The varbf/ 'on of fu/7'Z fo r-ecovery wi1h
wvy/7g -// -pa/rach e de/er; recovery a//emp fed by
open/n y parach~efe mounted cn outer w/2y //o.
Co/7tro/s sef af rudder w//h, a//erow's /eufral/
e/eva for down.


Fig. 15









NACA ARR No. L5G19a


Fig. 16


bD


o
0

Q)

0
cn
cr,



a
c.


1

aD
o
0
+-C


r


Figure 16.- Photographic record of free-spinning model tests
of airplane E showing a satisfactory recovery from the
spin effected by opening a 7-foot parachute (full-scale
value) attached to the outer wing tip with a 17-foot
towline (full-scale value ATIDL ADISoR coMMITTE FOR AERONAUTIC
LAOL1T MEMORIAL AEROIAUTICIL LABORATOT LAIODLET FIILD. VA.








NACA ARR No. L5G19a


I J NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS
0 20 40 60o 8 /oo 20
F/~//-Cca/e fow/ie /en,/th, f
F1Qure /7.- The var//a//a of turns for recovery
w//, tow//he /ey/lh; recovery a/tempfed by
openA/9 poarac/hute lVoun,/ed on outer wnqy
t 0,. Cotro/ls set at c rudder with, cr/erons
neatra/7 e/evator / ap.


Qj
K
K
Cs'


Fig. 17

























































































































5








NACA ARR No. L5G19a


cn
-I


'-4
o
0
C.a

3C
U
05
L<
cfl
f^


o)a


0 1)
I-o
C


Figure 18.- Photographic record of free-spinning model tests
of airplane E showing an outer-wing-tip parachute attached
directly to the wing tip (no towline). Frames 14 and 15
show parachute collapse. Parachute does not effect a
satisfactory recovery from the spin. Full-scale parachute
diameter, 4 feet.

NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS
LAHOLET MEMORIAL ARROIUTICAL LABORATORY LANGLEY FIBLD, VA.


Fig. 18












































































6"







NACA ARR No. L5GI9a


C)

w
icn,
C.) a)
*I-'0

4' C


Figure 19.- Photographic record of free-spinning model tests
of airplane E showing a parachute attached to the outer
wing tip with a long towline hitting the tail surfaces.
Parachute diameter, 4 feet; towline length, 34.5 feet;
(full-scale values).

NATIONAL ADVISORY COMMITYEI FOR AERONAUTICS
LAINOLET MEMORIAL IARONIUTICAL LABORATORT LANOLET FIELD. VA.


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4-,




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Fig. 19










NACA ARR No. L5G19l


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Fig. 20


Figure 20.- Photographic record of free-spinning model tests
of airplane D showing the direction of spin changing from
right to left because of the large yawing moment of the
wing-tip parachute. Full-scale parachute diameter,
5 feet.


NATIONAL ADVISORT COMMITTEE FOR AERONAUTICS
LANOLET MEMORIAL AERONAUTICAL LABORATOAT LANMLEI FrILD. VA









NACA ARR No. L5G19a


- f / CT L./
Fu/l-sca/e diame/rerscaledoup from/ mode/s/ize ff
Fure 2 /.-7The varia if/on o / Iurns / for recovery wi/h
w/nmy-1p-pbarachu;e d/armefer recovery ajtiemnpfie
by s/mnu/taneous/y openingparachLuts monf/e.d.
onbo h wing ftis.Conyro/s eS ofa rudder with,
a//erols neo fra,/e/e vo for up .


Fig. 21





NACA ARR No. L5G19a


A_ /o/alwe Towi/ne
/enth

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-C


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS
5" 6s 7 8 9 /o
a/- //-so/e d/azmefer yea/ed u from m,,od'e/ size, f/
/ areZ2.-The var/-tiof of /ur-s P/r recovery
wi //ry-/-//o-pargcz-ucate do/areeer recovery
aftempfo'ed 6y s/a/fo eou/y o/oen/?//y archa es
mounted 0on oth wk/dy f/s. Co7tro/0s et at
ruodder wi//, a//erv s neutrar/ e/evatcfneu/raz/


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Fig. 22





NACA ARR No. L5G19a


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2


F//-sca/e c/iz-eter sca/eod up from moode/ size, /f
yurerf3.Te vaelation of fute-s for recovery
W/th wnn/y-/o -/-paracate /b7we/fe- recovery
al//einpted' y sim6/faneous/y ooeoy gparacta tes
mounted on bo/h winy f/s. Controls se/ a/ rudder
w/ 4, al/erons neufra/a e/evator down.


Fig. 23





NACA ARR No. L5G19a


9 / 20 30 40 5o0 6 76
l//l-scale -fow//ne /en//7Y, //
F/iyure 24.-The var/ki /on of l'urns for recovery w/l/
fow/'ne /en iyh recovery a/fempt/edhby s u/Pfaneous/y
openiQ/nQ a racrcues m77c ed o,7bof/h w; /"ps. Con fro/s
set citf rdder wif, ai/erons neu ra/e/evalrc/'own.


Fig. 24






NACA ARR No. L5G19a


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NATIONAL ADVISORY
COMMITTEE FOI A EROIAUTICS


/ c 6 7 8 9
Fu/i-scale d/wme fer scaled up from mooel size, ft


Fcure 25.- The effec of fes T attitude on fhe variation
of turns for recovery with parachute diameter for
model E; recovery offempfed by opening fail parachute.
Towline length, 34.5 feef; controls set at rudder with,
ad/erons neutral, elevator up.


Fig. 25





NACA ARR No. L5Gl9a


( 3







__ __20000 f
/ ) ^ ----- J /------


NATIONAL ADVISORY
COMMITTEE FOR AERONAUTICS


0 20 40 60 60 /00
/F//-sca/e tow/lne /e'qqh, ft
Tyare 2 77- The effect of tesf a//fifde on f/he
vari/v/at/ of ft/ra'tn for recovery wifh tow//ne
length for mode l recovery t7ffempted by opening
hail parachute, Parachu-te di/meter, 7 feel ; controls
set of rudder w//h, alYeron.s rneura/, ele va/-ors
UP.


Fig. 26





NACA ARR No. L5G19a


(I,

zS


11//-jcol/e


diometer jero/o' up from mode/ size, ff


Fu/re 2 7 The effectobftet a/titude on the voriolion
of turns for recovery with parachute dc/ameter for
model E, recovery offempf'ed by opening pQrachu7e
mounted on outer w/g f/p. 7bw/le length 34-5feef;
controls set of rudder wvylh, ao'dlon. neutrQ/j
elevator up.


Fig. 27


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UNIVERSITY OF FLORIDA

3 1262 08104 953 7


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