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Development of 2 underseat energy absorbers for application to crashworthy passenger seats for general aviation aircraft

19840024297 · NASA · 1979

Public domain · NASATechnical Reports

Overview

This report presents the methodology and results of a program conducted to develop two underseat energy absorber (E/A) concepts for application to nonadjustable crashworthy passenger seats for general aviation aircraft. One concept utilizes an inflated air bag, and the other, a convoluted sheet…

Publisher
NASA
Document
19840024297
Year
1979
Pages
103
Chapters
4

APPENDIX A

APPENDIX A Seat With Shoulder Strap Inertia Reel Mounted Upon Bulkhead The shoulder strap inertia reel in the first seat configura- tion invest~gated was mounted on the cabin sidewall or bulkhead approximately 18 in. behind and several inches below the shoulder.

The shoulder strap is not attached to the seat back, but rather passes through a hole in the seat back which maintains the proper strap he~ght relat~ve to the occupant's shoulder. As shown in Fig- ure AI, the section of shoulder strap between the inertia reel and seat back can swing during the vertical E/A stroke to maintain oc- cupant restraint without interfering with the vertical stroke.

Shoulder strap swings without having to lengthen to accomodate stroke. _J Bulkhead Unstroked Stroked

. "

Figure AI. Stroked and unstroked configuration with shoulder strap connected to bulkhead.

When loaded in the forward direction, approximately 40 per- cent of the occupant's inertial load can be carried by the shoulder strap to the airframe, bypassing the seat frame. This can reduce the seat frame weight and/or increase the forward deceleration at which the occupant can be safety restrained.

However, the design has some drawbacks: the large outward buckling displacements of aircraft cabin sidewalls during a crash could pull the seat over sideways if the inertia reel were attached to the sidewall; and there is not always enough room between a seat and the bulkhead behind it for the length of shoulder strap required to prevent unhindered vertical stroke.

If the inertia reel can be mounted in the required position, and the hard po~nt to which it is attached cannot move greatly rel- ative to the seat floor attachments, this seat configuration should be ser~ously considered.

APPENDIX B

APPENDIX B Calculation of Long1tudinal or Lateral Accelerat10n Which Will Overturn Freestanding Seat Mounted on Bellows E/A Assume that the seat system shown in the figure below is sub- Jected to a forward load F applied at the c.g. of the occupant.

Total occupant and seat bucket weight is 223 lb. Thickness, t, is ne1ther the wall thickness or the convolution depth, but rather a variable representing the equivalent thickness of a dummy material whose crush strength per un1t circumferential length is equivalent to that of the bellows. In other words, the physical bellows has been replaced for purposes of this calculation by a nonconvoluted, stra1ght cylindrical tube of radius R and thickness t, whose crush strength in the axial direction 1S s1zed to provide the required vertical limit load.

The crush strength of such a cylinder in the vertical di- rection is given by: y

F."---

F 27rRt = S A = S Y Y

i

Where F = crushing load, L

x--1

total, pounds = material S yield

1 y

strength, psi R A = area, in2.

Solving for S and recall- ing that the desir~d limit load is 1987 Ib: S = 27rRT (1) Y The moment of inertia, I, of a cylinder where t« R is given by: (2 ) The allowable bending moment, Mis: (3 ) Where R = radius = distance to extreme fiber from neutral axis.

Combination of equations 1, 2, and 3 yields: 1987 R t 1987 R

M = 27rRt --R- =

M = 7948 in-lb

The moment, M, is also equal to FL = WaLe

Where W = occupant weight and

a = acceleration load factor

L = distance from c.g. to floor = 25 in.

Solving for a yields: M

a = = 1.42 G

WL

APPENDIX C

APPENDIX C

Air Bag Analytic Computer Program

and Output From Test 1

The computer program shown in Figure Cl is designed to 1nte-

grate all the dynamic processes in steps of 0.001 sec. Before in-

tegration beg1ns, the in1tial conditions such as charging pressure,

orifice size, moving mass, and orifice flow coefficient are set by

reading data cards. The deceleration/time coordinates of the ac-

tual 1nput crash pulse and the diameter/length coordinates of the

measured air bag are also read into the model by data cards and

stored in arrays.

Once the iteration is begun, input deceleration is interpo-

lated from the deceleration/time array. The input deceleration

eventually rises above the level at which it can be passed on to

the test mass by the air bag force (initial pressure x initial

area). Relative acceleration then begins to exist between the air-

frame (input) and seat (test mass). This acceleration is double

integrated to obtain: first, relative velocity, then relative dis-

placement (stroke). The new pressure due to the contracting air

bag volume is calculated by adiabatic gas equations at each 0.001

sec interval and used at the following time increment to calculate

the seat deceleration. After a stroke of 1.2 in., the orifice

opens and air begins escaping from the air bag control volume.

The mass rate of flow is calculated using a sharp-edged orifice

flow equation and then integrated over each 0.001 sec time inter-

val. The mass of air 1n the bag is then reduced by the amount ex-

hausted, and the new remaining air mass 1S used in the gas equation

to calculate the pressure for the next iterat1on.

The 1teration proceeds in the above manner until the avail-

able stroke 1S used up or until the time limit is reached. At each

time 1ncrement, the maJor variables are printed out and plotted as

shown in the example of F1gure C2. Figure C2 shows the theoretical

performance of the air bag calculated from the initial conditions

and input deceleration of Dynamic Air Bag Test Number 1. The ac-

tual measured deceleration has been penciled onto the plot in

dashed lines, and measured pressures and strokes have been entered

bes1de the theoretical tabulated values for comparison.

GASIAfI.,T4(',FS.

ACCOU~JT • HEADING.SI SlwULA.

''TN.A.

LGO.

OOOOOOOOOCOO~J0. 0'-'-

PPOGI'I'~ .• .1.",1." :·".T. 01 ''''LT. TAPEI = INPUTI

PEAL " "I'"n~SIO''' xII ," TCI!CII. GGClCI. CASEI8ltSOllOI. DDll;:' C INITIALIZE CO~~T-'rS 1>1 ., 3.1 .. 159 p=53.3 PAT~ ., \ ... 7 0 144.

TwAX ., .15

OT = .'01

C REAP AND PAINT PA6E ~EADIN6

40 READ 50. ICASEIJI. J = 1·81

50 rORI-IATlilAlOI If" IEorllll 10~~' ~5 55 PRI"T 60, (CA<;[ IJI. J = 1.,,1 60 FOPMATIlrll. ~AI~. II C READ H'PL'T PULSE COO"::-hATiOS. CTI,..E. GI 112 READ 114,IITC(JI, C'IJII. J = I.lel 114 'C~w~'T12'lO.5) C PEAP AIQBAG S~APE ~E~C~IPTIOh IS'TpnKE. DIA)

READ 114. II~~IJI, 001JII. J = ).101

C CALCULATE AI~9AG I"'IT!AL VDLUwE OI"ln ., O.

ADISK "' O.

JS = 1

00 160 J = ). 14e

5 = J/IO.

1, IS .LE. C;DIJS'III GL' TO 170 JS ~ JS • 1 170 "Ill. " DDIJSI. 1~-SJIJSll ~IL'~ IJ<;'/l-['DIJ", I/ISDIJS'I 1-5[11,1,\\ bDISK ., PI·DIA··2/14~1441 180 I)Jt~I1 = '1"'11 • :'j)1~r<·.1/)2.

OINIT = QIt.IT -111..~··:--.··21·pl·l.5/ ... /17Zb.

C READ A~D P~l"'T I"'DE~E~CE~T OAQA'ETE':;" 140 oEAD 15v. D~ • •• ~. c. F~CT0K ISO 'O~~ATI5'1~.51 IFIEC'llI1IDO~.160 160 PPIN'T 12(.0"" ., C· FACTO~ 120 ,OR~ATI14HIOkIFICE DIA = F~.2. 0 INC" EFfECTIvE wT •••• C f4.0, • LM~ •• '. fL~~ CGEF. =0. fl..? 0 FACTO~ ••• f~.O/I C SET INITIAL CO~CITIONS o = QII<IT P • p • 1~4 • PAT~ PN~~ u p 'T["'P ~ C;7C • .. = ~"a/IP·TE"P)

ARC = FI.D~··2/(4·14~1

JJ = 1 0

JS = 1

I( 3 V o.

5 = o.

T O.

nVA = u.

C PRINT COLU~N "EAD!~G

PRINT .?!'O _ _ . ------_.-J

o ZOO 'OP~AT 11/° t.CCEL. IIELUC. 5T,,0"E P.;>ESS. OIA. T1"1t -, PQINT 250 250 rCRMATI4DH G v.FPS S.I~ P,~51 D,IN SEC C 'EGIN ITEPATION. CALCULATE DE~E"'DENT vA~IA~LES CD TO 3eo

270 T = T • OT

C CALCULATE AIP,~A"'E ACCELER~TIO~. GA. By INTERPOLATION BETwEtN nAlA POINTS 300 IF IT .LE. TOIJJ'II 1 GO TO 350

JJ = JJ • 1

350 GA = GOIJJI'(T-TOIJJIIO(GOIJJ'II-GOIJJ)'/ITDIJJ'II-TDIJJII

C CALCULATE AIR6AG DIA"'ETEQ T~EN APEA IF IS .LE. S['lIJS'll I GO TO 370 IflS .LT. SDIJSII JS "' JS-Z JS ., JS • I

370 01A = ODIJSI'IS-5DIJSI,OIOD(JS'II-DDIJSII/ISDIJS'11-SOIJSII

A = PI • DIAooZ I 14.)441

C CALCULATE o~lFICE APEA. AI' IFIS .LT. 1.21 AR = O.

IFIS .GE. 1.2) AP = APO

C CALCULATE SEAT ACCELERATION. GS

,C = IF_PAT~1/14~.12S.·V/22.·FACTOR

es = 1?_PAT~loIA-AR¥1.290C.61/ •• FC

If"lS _.E~. 9 •• AND. GS .GT. GAl GS = GA __ _

1'lgure Cl..

Alr bag analytic computer

program, "GASBAG".

C CALCULATE ACCELEPATION OF SEAT ~ELATlvE TO AIRFRAME. GSA

(IOSA = GA - CS

C INTESRATE ACCEL TO O~TAIN VELOCITY AND DISPLACEMENT. V AND 5

V = V·GSA~OT03~.2

S :: S·V"OT"l~.

IF IS .CT. 13.) 1'0 TO "'Cl' C CALCULATE VOLu~E CHAhGE.OQ. AND l~lEGRAT[ TO O"TA!h hE~ 0 flO :: V"~ o :: 0 - OO"OT IrlO .LT. 0.) GO TO 90C C CALCULATE ~ASS ~ATE Of EXHAUST.DuE' • AND INTEGRATE fO~ NE~ TOTAL MASS PP :: P/PATp..

IF IP .LT. PATM) p" :: I-'AT"/"

IF Ii' .[C. PAT") GO TO 51 ~ C~EJ • 2.0soC"AwoPAT~"IP~··.283°IP" ··.283-1.I/T[MPI·o.S 500 u :: M - OuEx 0 OT "IP-PAT~) 1 IA~SIP-~ATMII C SOLVE GAS E~NS FOP NE~ PkE~S~~E ANG TEMPE~ATURE 510 PNE~ & P ., ..... TEuP 1 , TE~P • TE~P.IPNE~/P)"·D.2!3 p :: PhE~ C INTE5PATE AIRFRAME ACCEL TO 05TAIN TOTAL INPUT VELOCITY CHANGE o flVA :: OVA ·GA OT"32.2 550 Cn"TH,uE C SCALE VARIABLES FOR PLOTTING IGA :: GA"I.gS ·5 IfClGA .GT. 951 IGA :: :;

IGS = GS·I.~5 • 5

IV = V • 5 IFI!V .LT. II Iv :: IS 5 0 2 • 5 pp ., P/144 - 1~.7 1 0 ., PP • 5 10 ., OIA .. 2 • 5 C CLEAP PLOT LINE [JO t.00 J= 1.95 XIJ) ., IH ~ 00 CO';T I '1UE C LOAD PLOT LI hE .. 1 T" (JIIT,:>uT C .... A;...CTE'<!:> XCIDI 1"0

J (15) = I"'S

J (1\1) "' IHv X (Ii') ., 1,,0 X (Ie:.) z IHC ---- i"llGSl-;")M(, - X (5' :: I H" C PLOT PRI"T 70D. G5. V. s. PR. OIA. T. IXIJI, J 1.95) 700 FO~u~TIl'" • 5IFb.?IX). f4.3. 95AI) IF I T .LT. T ... 4.I;) (,(\ TO 270 C END or ITE~ATIOh ~O TO 9U 900 PRl".T 910 910 fOP~AT(lrl • ~6A. 12H~0TTouED OUT) 920 PDI"i 930. DVA. OI~IT 930 fo o ":'TII6 vELOCIT¥ c,..,urE OF I',"'-IT PULSE =6. F4.).· .. T/SEC ...

C.. INITIAL VOL. :6. F~.3)

GC TO 140 1000 STCP END 00000000COC0000uOOuOC~ TEST NU~REk I. BELL-SHAPED AIRBAG O. O.

0.029 32.06 Q 0.03 4<>.03 0.064 43.91' 0.048 li.26 0.056 13.15 0.0€>7 O.

0.2<;0 O.

0.250 O.

0.250 O.

O. 6.2 .15 7.t .45 9 ....

1. 10.27 7. 10.3S 8.5 10.92 10.5 12.50 12.5 14.42 13.5 15.06 15.5 15.0b .B5 2.18 138.0 26.6 5.

OOOOOOOOOOOO~OOOCOOOOC

Al.r bag analytic computer

Fl.gure CI.

program, "GASBAG" (contd).

.J

6"

z £

...J

Ow U

U F=:,7

uu U

u <!.~

Cl

• Q

u

• llJr,{

u

uJ

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~a~

·

U

~

..,

zlL u

/-:z u

,:>0 • 0u.

u 0.-

~G

::zG

-Iii u r::L2

· ~ wo

$ u ~Z:i

· •

u

4.~

• ~~

u OlZ

<1:.(l. u ~ \)- u

'J.

$ u

t\8

u

·

(l/.~

0 u $ ?

U tIl~ ~2.

u ...J

III 3

·

...J ~<f.

·

...J

·

.r U In ...

lo 0

z -

-.+-

...J ...J

·

, «

·

U

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u :l. ;. ;.

- -

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» J1Jl :.

Jl,fl > » JlJl » flJ'l Jlo.fl » ;»> Jlo.fl ; fl,flo.fl »

· •

::: flflfl

»> ~n~~n~

·

~ # 0 0 .00 • 0 0 0 0 ~ ~ ~ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 • 0 • 0 0 ~ • • 0 .0. • 0 • • • • • • • 0 • • • 0

·

:: ~ ~ .J ~ '=' - "\J .., ~ ..Il .0 r- L 7' ::ll- ~ .., ~ ..Il C - L 3'- ~I_ '\J -"J ~ .n .J;) - x:: ~ 0)- "\,I • .., .: .!'I ,::J - .:J ,.. ,j)- \,I'" ~ J'I .c r-- .ll ,.. 0)- "\J .., ..:- J'I.o

g~===~c===~- ________ ~~~~~~~~~~-~~~~~~~~~ •••••• r ••• .fl.fl.fl~flflfl

~ Jl

'" ====o=~===~===o====~=~~=================~======~===~=o00=

· . . . . . . . . . . .~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

· •

"

~==~~===-~~=n~-~o~-~=~n=~~--~=.--~~D::::::::~??~==O ___ ~~~~~~.

Z, >

·

~~~~~~:~~~:~~~~~~~:~~~~~;~~~~~:~~~~~~~~~~~~~~;~;~~~;;~;~~ <: -.

CDCL~OO.J;)~C~C.J;)o.oCC~r---r-~L~~~~~~~~~~~~~~~~~~~?~~~~~~~?~~~ ~~~

-

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· ----------------------------

-'

·

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·

~~~~o~~~~_~~~~~-n~3-~~-n~~~~~~~~~-~-~o~-~~c--~~~o ___ o~~n~

·

fl • CD~D~CC~C~~~~~~~--~~~~~~~-~~~~_~~no~~~~~O~M~~~~-~~~~~~-~~J

:. J'

.. . .. . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. ........................................................ ..

J1 :>..

.

~~ •• :: •••••• : •••••••• nflnfln.flDC~-~~~-Dnn.r.~~~N~~N~----Ooo~

=<:>.'

·

:>.

...J $ Z ..... :::::::::=::::::~:::::::~::::::::::~::SN=:::::::~~::::=::~~:

·

;;::. ~~~~~~~~~~J~~~~~--~N~~~~~~D-D~~_~~~D-~ ~~nno~r~ ~~-o~~- ~ . .. . . .. .. .. .. .. .. .. .. .. .. . .. .. .. .. .. .. .. .. .. . .. .. .. .. .. .. .. .. .. .. .. .... ................ .............. ..

::::> -.

'" J~~~~ ________ ~~~~~~~~ ~~~~n~n ~

:: fl •

'"

·

J;

'" ~~J~~~rN~~~~~~_~~_J_~~-~~n~~~-~~-1~~~~~~~~~~~~n~~~~~~~~~o

U J1 • =O~O=O~_~M~~ON~=~~~.~~~n~~M=M=M~.OD.-~~~Dfl.M_DN ••••• M~N-_

·

.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . . . . .. .. . . . . . . .. .. .. .. .. .. .. . .. .. .. . .. .. .. .. .. ..

... .::>:>. •

........ ~oov~ ____ N~~~~ •• ~nn~~~~~=~='_NN~.~D~~~~ooo~o~~aoQO

0 • 0 u.J -------------NNNNNN~NNN~ > >.

"- O __ ~~~~c~XC~N_~N~~~O~O~~~~O~ __ ~MM~O ___ ~--N~-~~~~~~_~_~~N~ ....

·

O_~M~MM~~~~~XON~~N~~---M~M~~-~~M~~~~_~~~~jMMNNN-O~~~~M_O~ ....

.. .. .. .. .. .. .. . . . .. . . . . . .. .. .. . . . . . . . . . . . . .. . . . .. .. .. .. .. ............................ ..

...

u.J

u <:>. O_NM~~~~~~~~~~~~~~~~~O_N~~~~~~~~=~~~OO~~~~~~~~~~~~~~~~~~~~ u

5 «

• ----------------~-------------------

Figure

C2. Analytical model output

using initial

conditions

of air bag Test No.1.

..

LU :t

~

;: VI

~

III

~

u.

!{

:r

IJI I- IX

~~

'=l

~

~S

;Z~ ...

'" 011.

~ ~p.

t- ~u.

,...

fio

0()

w~

to ~~

B~

LU

vEt

:i <1:0

0 ;z3l

...I(l..

~

~!) '/I F.~

&

,J

t3 Wb

«

g:i :I

ill

~~

~

~~

llJ-

A>

0-

, ~

~ - ~::l O~O::lOO o O::lOO U ..J , JI ' .... D!1' :>1- 1'\1"" : .t'I C - U ,.. ~- '\, ..., .: nor- ::. ,.. J- '\J 4Ij f ...... ,c. ,.... 1) ,. ~- "..., ~ J"I c .... .D .,.. ,:, '- , 1: X ;- ~ "7 oJ' 7' ,. l' ,. J" ~ 0\ .T' /"I l' '" Jj C)..c &,. c £. C C .:'" -- - - .... - - ,... - f"-- - :;. 1;:t :. 1: '!) .u I :>:"="O=>,;);tj':).;)O:>~ oO~OJ':'':)J''j- 'J:;>~=-~~ -=»J,:);:)J~..::t~":)~.,::;)_

!

;:; · ............................. . . ........... .

.

fl

"

..J J'O ....

::> :..

::> } ~ ...

1:1 ..., ~ t-"J ~ ~ ::. \,i"'1 _ '" - ¥ 'Ii M..... , J'" n..,..., f') .. ~ <OJ oJ"" .Go {) D -J ... fI CI !j 'J e 0 d\ f'I .., 0 ":) • ..., ~ ~ "l:. ~ ..J' _ :1' J "" L • -: -z ~ U"' - '" J L ., J" WI _ r- -, J .. "J "J' oL n _ :L ...J .,. ('.I - ,. "1.1 ,.... It:) .n.:r # ,., · . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........... .

r

'"

~~~~~nTS~-c.C~~"~~~~~--~~J':~~~1L'~~~~~~~~~ -'

---------------------------

..

~~~C-~3--~~~~~ __ ~ __ ~-~~?~~~~e~~o~~~_,~~~~~~M ~~Noc~~£rM ___ ooC~~.-O~N~.~~O~~_~~_~~MllMo~~ ••

- u

· .......................................... .

~~~r.~ ••• ,~ •• ?~~~-~N~~---oa~~~~~c~ •• ~~~NN~~ ...

...

---------------------------

>

output using initial

Figure C2. Analytical model condi-

1 (contd).

tions of a1.r bag Test No.

APPENDIX 0

APPENDIX 0

Double Integration of Measured Decelerations

to Obtain Stroke

The integrat10n routine shown in Figure 01 was made originally

to analyze a curious set of circumstances that occurred during the

bellows dynamic test. The test mass bottomed out with considerable

residual velocity, even though the oscillograph record showed the

deceleration to be adequate. It was thought possible that the slow

rise of test mass deceleration over its first fraction of an inch

of stroke could allow the buildup of a considerable relative veloc-

ity that would consume the remaining stroke prematurely. In fact,

by using the integration program shown in Figure 01, this was found

to be the case. The measured input deceleration and attenuated

test mass deceleration were entered into the program and integrated

to obta1n stroke. The results showed a large residual velocity

after the available stroke had been utilized.

The conclus10n drawn from this, and discussed at some length

in the main body of the report, is that an E/A must have a very

h1gh elast1c spring rate in order to minimize the stroke require-

ment. Two sample printouts that illustrate this point clearly are

shown in Figures 02 and 03. Figure 02 shows that a stroke of 10.9

in. is required to decelerate the test mass at 14.5 G when its de-

celerat10n rises simultaneously with the input deceleration. Fig-

ure 03 shows that a stroke of 13.9 1n. is required to decelerate

the test mass at 14.5 G if its 1nitial deceleration rises linearly

over the first 0.25 in. of stroke, such as would occur with an E/A

having 0.25 in. of elastic deflection before reaching its limit

load. On the printouts, the velocity, V, is in ft/sec, and the

stroke, S, 1S 1n 1nches. Airframe deceleration 1S tabulated under

the column heading "GA" and plotted with the symbol "C." Attenu-

ated seat bucket deceleration is tabulated under the column heading

"GB" and plotted with the symbol "G." Th1s symbol "G" does not

represent the acceleration of grav1ty as it does in the main body

of the report.

P-<Vh~A" .... LO r (It,i-'uT. ("ui PuT.

14PU = I "'''UT)

ull"trl~lv'j Tl-.ull.::). uAl.d1.::). 1':)U112)o \3r<0112l. )1,(10:')

t ~i~U IN~UT ~ULS~ tLO~Ol~AT~S

100 .... ~AU Jlt ,«(lt.!J(J). GAU(J».

J = 1.}2)

11 j F I.,)",~, A T (iF III .5)

120 f-'~AU IlvO(<T~D(J).GbUIJ». J= 1 d2)

I ~ (t.I) F ( 1 1 1 1 II U V • 1 C 5

I?'::> r'r<ir'd IJ'J

S T ~/)

13C f~~~~T(lHl.ll* GA Gb V

5 = 0.

V = O.

1 = O.

OT = .0u1

UV = 1,..

JA =

J<j = 1

C COMPUTE AIRF~t.Ml ACl~L~HATIUN

15t. If (r .LE. rt.U (JJ.,+l» uU TO 200

JA = JA +1

2U0 G~ = ~AU(JA)+(1-TA0(JA»OIGAO(JA+l)-GADIJA»/ITAO(JA+l)-TAO(JA»

C CO~i-'uTE StAT bUC~ET ~lCtL~KATION

If IT .LE .• Ibt;IJt:l+l» ~O TO 300

JIj = J~ + 1

300 b~ = u~UIJb)+IT-TbU(J~»·(G~U(J~+I)-GbU(J~»/(T~O(J8+1)-T~D(Jd»

C It" Tt.G .... A 1 E.

ut:S~ = GA - LJo

V = V + ~h~oul·Jc • .:: ::, = ::, + V·C-T~12.

IF(,:> .,H. 13.1,,) (,Ii 10 ~\JO

uV = UV + DT·uAoli • .::

C ::'CALt. VA~iAbLt.S FUR PLUTTING

l!.,~ = GAo"+lu

ll:>~ = G8*2+1U

IV = v+lC

l~ = ':>*2+}u

C LO .. O PLUl L11.t. Id TH lJU1~UT CtiAf-'ACTt:KS

UV 40] J = 1. 1~~

411(1 x(J) = Ih

X (! GA) = 1 He

I. I I urI) = 1 HG

A ( I V) = 1 hV

).. ( I ~) = 1 h::,

" ( Ill) = 1 H*

C IJLOT

t't-<}t.T e()o. GA. btl. V. 5, T, P,(J), J = 1, 105)

I:lc,c F-U~""Al(l"-t • 4(~ ... 1' IX), f4.j, lu5All

T = T + IJT

IF(1 .LE. u.1(0) GO TO ISu

~OO P~I"'T 91u. uv

~l~ F0~~~T(/1H , *lNPul PULSE v~LUCITY CHAN6~ = *. FS.2. * FT/SEC*)

G~ TO 12u

1000 ~lUP

UHJ

computer program to double integrate measured

Figure Dl.

decelerations to obtain stroke.

0.0 o.~ ~ • ..I .OJ: C.O • .,01 1.8 1.~

· "

3.6 J.6 :l.e .. '02

5.3 5.3 :.= ]0)

7.1 1.1 C., .Jt.I ..

9.q ~ q ~ .C ~.o .JOS

c.o .0\1";)

10.7 10.7 0.0 G

o .C 12 ... 12.4 ~.J .;):)7

;).J .. CO .. G

o 0 1 ... , 1 ... 2

.,; .00 ~ G C 16.0 14.5 .0 • .; .Ole,. C 17.8 14.5 .2 lQ.6 14.S .3 .011 G

21.3 14.'5 5 .w .:J 12 'v

., .... 013 G Z3.1 14.5

G C 24.Gi 11o.S 1.1 .... 01- • v G C 26.7 }".'5 1.5 .l .0 If:, v

G c

2~." 1 •• 5 Z.il .1 .JI'3

G c

JO.2 11o.S 2.5 .1 .017

G c

3Z.0 1,..5 3.1 .1.\l1i!.

,

(, c

33.8 14.5 3.7 2 .ill Q

G c

35.6 14.5 .Z .;2~

'.- ,

.3 .;21 G c

37.3 1'.S ~.1 y G 39.1 14..5 5.-i ..... ... Z?

c

.O.q 10.5 G c.7 .5 .~ZJ

c

G

4Z.7 14.5 7 • .5 .n-

404 .... 1"'.5 ~.~ .1:> .')2'3

"

~.tl .~ J2" .6.2 14.5

., G

48.0 11t,1i:: IC.7 .Q e27 "

G 4 .... 2 1 •• :' .I •• 1.C JZIi • 5 lZ 7 !.2 • ~l'" .~." 14.5 · ,

" c

42.7 14.= 13.0 I 3 .03 • > y " , 1.5 .)J 1 40.9 1 •• = 1,- ...

3Q.l 110.1; 13.2 1.7 .J3? 5

1>'

,

G • c

37.3 lIt.S Ib.J l.~ ~JJ

c

3S.~ 1 •• S H.7 2.1 .::.3'0 5

c

33 •• 14.5 17. J 2.3 .035 S "

" v

c

2.5 .JJ'" 5 G V n.o 1".5 .1 ....

c

30.2 '4.S p. ! 2.7 .")7 5

14 50 1 .. 5 c

3 C .:u-

ze ."

"

Z •• 7 ,40,5 ";.; 3.2 .JJ .. 5 G C , G 24.9 14 5 :;.5 J.-

.\1""

h.5 1;.:;; 3.7 .(i4) 23.1 >

" v C

ZI.3 1 ... 5 cO. ~ J.G .0'-2 G G • Cv 1 •• 6 14.5 2: 2 .. J • )"3 y G 17.e 1 ... 5 2"'.J • ..1- ..

r, C ,4.=> 2"1.'

l~.O

-.'

1 ... 2 14.5 20.3

J-' C"

•• 7 I> 12 ... 14.5 2~.) 13.1 5 ...

10.7 lo1t.S 2').1 ... '-'"

5.;:) • .;_..; "

8 •• 1"'.~ 2C :)

7.1 }4..~ 1 Q 7 s.~ .JS~ "

C 5 G

5.3 14.5 49 ... ">.1."'51 "

14 5 };.1 5 G v 1.9 )4.1:; le.7 I!:l 5 :JS3 5 G v ".1 • :)'5 .. S G .~ ''''.: 1 e.l O.C 14.5 17.' 7 •• G 0." 1'.5 17.3 7.2 " y 7._ G V 0.0 I •• : l~.- 5 O.il 14.5 10.3 7.0 5 G

7., G v

0.0 14.5 15.':; 1. Q 5 Gv 14.5 15 ..

'.0 14.5 l ... ~ < 0.0 - I .G 0.0 h.S 14.5 V G 0.0 14.5 14. J S y G O.il J •• 5 13.5 0.0 '4.5 1 J., S G 1 •• 5 lZ.o S G 0.0 0.0 14.5 .2.1 i).il 1 ... 5 11.7 ..;.2 .Jt."

Q y

•• 0 H..S 11 .. 2 ".J • :t-

" G

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";.t! ,)71 5, G }4.:S l :.3

'.0

.... 7 ." 7? 5 G 0.0 '7.t! • )73 O.il .5 o , 5 -1.9 .J74 C .il G y S I> 0.0 ;j.4 lG.::: .:171S 7.9 10.1 ... 7~ 0.0 S 7.3 10.2 :71 5

0.0 "

0.0 7.0 10.3 .07- "

".3 I:J ... ,nl;; . G

C.O "

0.0 6.1 1 c 5 ."~II • > G , , 0.0 5.":: 10 5 .Q~I G 0.0 5.1 Ie 0 • ..1"7 • 5 0.0 4.7 HI t; .0013 • 5

"

, 5 G

0.0 "

4.2 10.7 .~"'" 0.0 .j.7 10 7 .e':lS 5 G 0.0 3JI0~.lSt; 5 G 0.0 • 5 G

z 01 '0.':= • '~7

, 5 0.0 2.3 I ~.~ Jf-~ 0.0 1.:; II). 'i .OPoq G

5 "

0.0 1 ... 10 ; .J~O • y 5 .,y 1!:.<;O .~ql G

0.0 'v S "

0.0 .5 1 ,.~ .C~;:O S G 10 :;. ,. S 0.0 -.0 G 10.9 •• 5 0.0 - .0 ,. 5 0.0 -.0 10. ;f 0.0 -.0 10.'1 V' 5 O.il - • .J 10.9 " S 0.0 - 0 10" V' S 0.0 10.; v· 5 - 0 Figure D2.

Integration of stroke, S, assuming that

bucket deceleration, GB, r~ses simultaneously

with airframe deceleration, GA.

G. U

0.0 t.o O.C .OC ...

0.0 (

1.8 O.C .1 ., vel

-

3.~ .t ? .D lOon

.0 .003

5.3 .. .3

-, .0 .00- 7.1

.-

-, .o~- B.; .t , ., 1.1 .00" 10.7 1.3

-

:)('7 0 G 12 2.1 1.- .1

-

- 4 .0('-

1 .2 3.1 I.' .1

Ib.C c.2 I .. C'::"

-.-

;> ; .~1 ..

17.8 .1 5.'

b 7.7 ,'Or; .2 .011 19.'

21.3 ~.J 2 .tlll' <. ' G 3.7 .3 .013 23.1 lZ.C ~

h.~ . 0 ,1-

,,".Ii

(, 2b. ,. l ... ~ .. ~lS

.. -

, G 4.- .. ott 2".4 1".5 G C

- 0

30.2 1~.5 S.- .S .017

., -, y G

) ... 5 .Olol 32.0 S.'

.- C

>., .e .. "I) Q

33.' ) •• 15

" -, C

35 •• 1 ... 5 .7 .ole

,. ."

-, G

" e •• .: .. ~,,)

37.3 h.:-

-, G

JQ.l I_ S ~. 7 .<; .el'''

G .023 5 "o.q h.5 1.0

'.'

G 4Z. ,. 14.-: 1: .5 1.2 .02'0 S

-

G ) .... 5 .e2S 5 H ~ • .3

"'''.'' -

G S 12.5 1._ .~2~ S "boo2 I-

-

, y

G "'S.C 1 ... 5 13 •• I •• .~21

- y

I.- .C'z~ 5 "b.2 )".5

1"."

y S G lS.~ 2.C .. c?t.

1".5

"'".- y

< G 2.;> .,3: "2.7 1,".5 1t..S G C 4Q .q 1 ... 5 17 .3 2 .01 5 (, -3- 5 39.1 1 •• S te.1 ?'

·

G

H., -33

37.3 t: .~ l".~ G

35.6 h.5 );.Cj 3.: .0)4

y :!.3 .,35 G 33.8 1 •• 5 Zeool C G Y 32.0 l .... ~ 20.7 3.S .C3t , G 3t1.? h .• iS 21.2 3."

• :37 a G ,1.1 1 .c 3 S C8 1~.5

Y

· .elc, 5 G

26.7 14.'=' ;:C: .. (j 4.': y G

z".q 1".1:;j 22'.-

.. 0"'"

'" G YC

23.1 14.15 ZZoo7 .. "41 y

cz. :; G C

21.3 14.S S.I ."1"1':

G c

C 50 ...

19.' 140.5 <J .c": G 17 .E h.'S 23.1 ~.1 .C" ..

G C ?h;i: e.O 16.0 14.5 .o"t;, y CG U .• S z~.z O.Z .\,14"- ]'".2 , V t.; G lZ.- h.15 Zl.1 .0"" y

e._ S G

10.1 1 ... '5 2.J.~ .01",;0 7.1 .r_t. < C G S •• 14.'5 ~~.- G 7.1 h.'S ;Z.f:! 1.~

."

, .fl:.} G 5.~ ) .... 5 1,.:'

.'

G 21.<; 7., 3.b 14.5 ~Sl' G

14.'5 Zl.~ e.l .C.1:.3 C S

I.e

-

e._ G

S

.c l ... ~ 11.1 • ~E,."

G Y 1,..'5 b.t S C.O 2' .~ .C'~= b <; 5 G V C. C 1 ... 5 2:1.1 "5- y .CC:~ G IIf.7 ... 1 C.C h.5 y G 3 ~5- c.o h.'S I'.c G V

· h.5 JF .• 7

o.c • tS ..

'.e

y )E..3 .Qt .. G 0.0 1 •• 5

'.-

G )_.5 )7.~ 1..0 • .,,61 C.C u O.C 1 •• 5 17 3 It.;> .. Ob?

<; G V ) •• 5 I. H .0"-"1 O.C

· G

C.C 1 •• 5 lb.- H.t ~64

.O~E.. G C.C ]~.c. 15.' 10.0

) •• 5 1l.C, .0"'''- O.C 1~.- ".

V C.O ) •• 5 IS 0 lI.c 67 11.:; .r~" 0.0 h.5 1'0.5

yG II.S S C.O J •• !:I 1 •• 0 .e~'" y & 1~.5 13.~ 11.7 .07 ... S 0.0 y .(,7) S G O.C ) •• 5 13 1 1l.E

)2 .... 12.L .cn S

C.O '0.5

G

" c.~ 1 ... '5 12.2 IZ.I .C7~ S

( 1;>.3 VS 0.0 l~.S 11.7 · "',.

y G )'-0.5 II.Z IZ 5 C.O • C"~

- ) ~.j;i .07", 5 G

0.0 )~.5 12.>

. G

IZ.o .el7 5 0.0 14.'5 le.3 , 5 G 0.0 1 •• 5 c;..~ )C:.t' .:7'- c v (, lZ .C7 S 0.0 14.'5 '., G

C.O S • 13.C .oe,; s

· 1".~

S G

c.o ) •• 5 13.1 .OFiI

e.'

S 14.51 B.C 13.2 .DP?

0.0

" 1.S S G

0.0 1'-0.5 13.3 • Jfl~ 5 G 0.0 1 •• 5 7.0 13.· .0 ....

, G

0.0 )4.~ e.b 13.· .uiilc, S

S &

0.0 1 •• 15 col 1 ~.5 .ef'''

1,".5 )3.1) .OE'1 S G C.O S.t> I) • S G

0.0 14.5 5.Z .0""

S G 0.0 1,".~ _.1 13.7 • ~E' G 13.7 .{ilil. S C.C 1 •• ~ '.Z ,

:; ... 5 G

C.O 14.5 13.,. .C91 )3 .. t' .i't;,2 0 S G 0.0 hi.S 3 .. ~ S G 0.0 14..5 2." )3 • ., .U~, v , .l'Iq .. S G c.o 1 •• 5 Z._ J3.r.

.~.; S G 0.0 1'-0.5 1.- 13."

1).1i- .oq ... S G

0.0 ) •• 5

I.·

<; -, S G

c.o l •• ~ 1.0 .{\C"i7

; -, S G

C.O 13.17

.C-"''''

'''.5

) •• C .~Q(, S G 0.0 h.> .0 yo S G O.C 14.5 13.q .lC~ <; S O.C 0.0 13 .101

-.- .-

o- S 0.0 I).' .10Z C.O

-.-

S

c.o O.C 13.Go .lC~

.-

y- S 0.0 13.,

C.O .10-

<; y- S 0.0 0.0 13 .HCi

-.-

y.

0.0 S O.C 13.' .10'"

-.-

y- 5 0.0 O.t' 13 .107 - ..

J.:! <; o' S

0.0 0.0 .tc.'''' - ----..l

over the first 0.25 in. of

stroke.

9i

REFERENCES

1. Crash Surv~val Design Gu~de. U.S. Army A~r Mob~lity Research

and Development Laboratory Technical Report 71-22, 1971.

2. Dreyfuss, H.: The Measure of Man - Human Factors Design.

Wh~tney Publicat~ons, Inc., 1960.

3. DesJardins, Stanley P.; and Harrison, Harold D.: The Design,

Fabrication, and Test~ng of an Integrally Armored Crashworthy

Crewseat. U.S. Army Air Mobility Research and Development

Laboratory Technical Report 71-54, January 1972.

End of Document

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Document details

Doc number
19840024297
Publisher
NASA
Year
1979
Pages
103
File size
4.1 MB
Chapters
4