LOS A LAMOS SCIENTIFIC LABORATORY · 2016. 10. 21. · A. Evaluation of TgO/W B. Evaluation of...
Transcript of LOS A LAMOS SCIENTIFIC LABORATORY · 2016. 10. 21. · A. Evaluation of TgO/W B. Evaluation of...
,,
[
99 ● ** ●●b.:, ●*8.* ● 0● ● O- ● .- e.-;-. ●
w-.—VERIFIEDUNCLASSIFIED
(
f
.“: iP
,.
-..,<.,/ !./~L,,yy
?>’‘: :-(-.,[’]4-2.;,.4-.+y’~,~,ij:*~~&Jfg#’&l JQ, &
__ LA-2459 ~-?
Copy No.m C.3
AECRESEARCHANDDEVELOPMENTREPORT.;
1,
1$,;
: ;;.;,!“
1:,, LOS A LAMOS SCIENTIFIC LABORATORY..,,.,.!! OF THE UNIVERSITY OF CALIFORNIA o LOS ALAMOS NEW MEXICO: .b(: jr; “
SINGLE STAGE NUCLEAR ROCKET STUDY
(TitleUnclassified)
.
.,,,..,/
~
;;”,,f;
,!
(
= I—
. . . . . .● ✎ ✎ ✎ ✎
0::. . . . ..*. “,:
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
8;
,, ,.
● ☛ ● ☛☛ ●
●:*m -:::.:O ::.:: 1● s ● *. :** :
.*. ~“~~:● 0 ● *m ● *a ● *8 ● *- ● *
8.● :9 ●: ..
● : :.. ::● ●:.: : ::G* ● em . .
LEGAL NOTICE
This report was prepared as an account of Govern-ment sponsoredwork.NeithertheUnitedStates, nor theCommission, nor any person acting on behalf of the Com-mission:
A. Makes any warranty or representation, expressedor implied, with respect to the accuracy, completeness, orusefulness of the information contained in this report, orthat the use of any information, apparatus, method, or pro-cess disclosed in this report may not infringe privatelyowned rights; or
k“’,”. “B. Assumes. any liabilities with respect to the useof, or ‘for damajges resulting from the use of any informa-tion, apparatus, method, or process disclosed in this re-
. port.
As used in the above, “person acting on behalf of theCommission” includes any employee or contractor of theCommission, or employee of such contractor, to the extentthat such employee or contractor of the Commission, oremployee of such contractor prepares, disseminates, orprovides access to, any information pursuant to his em- .ployment or contract with the Commission, or his employ-ment with such contractor.
.** ● 9** ● ** ● *
●** ● :: :: ::
● ..0 .*9O
● : 9.
● - ●:0:00●**:*.● *
● ✎ ● 99 ● ** ● ●. . . . . . . . . .*D,. .00 ● ***. . . . . . ● 00. . ...0 ..0. . . . . . . ..0
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● m 9** ● *6 ● *O ● ** ● O● **** ● *
%LA;24~ ~
&c -86, N H@’ ,+$OCKETS ANDRAM-JET EM-3679, 24th Ed.
This document consists of 7’7 pages
No.w
of 138 copies, Series A----
LOS ALAMOS SCIENTIFIC LABORATORYOF THEUNIVERSITYOF CALIFORNIA LOSALAMOS NEW MEXICO
REPORT WRITTEN: March 1960
REPORT DISTRIBUTED: July 17, 1961
PUBLICLY RELEASABLEPe FSS.1(3imte:Q-mOs
By CIC-14Date:/0-/7-95
SINGLE STAGE NUC LEAR ROCKET STUDY
(Title Unclassified)
by
E. HaddadW. Anderson
Contract W-7405 -ENG. 36 with the U. S. Atomic Energy Commission
This report expresses the opinions of the author orauthors and does not necessarily reflect the opinions
_ or vtews of the Los Alamos Scientific Laboratory.~
~— m0= (w
$3 ~_
‘?=.
~~ o)z= -
:===~~s ;
:— @_
-m
ZIE m
~o)<—
g=
-m‘—
-
m’ uw,w~~~90000 ● ** be
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
- ...~ .pft
:“:“::‘m.~.—.. 9* :0be ● *O ● O9 ● 9,* 9
9*
::.*
● ☛ 9** .- * --- –m.
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
~’””””’ - ----~● 9 9.* ● 99 ● -, ,** .0
“m~JT~~:b{
● ● 0 ● 9● ● ● O ● ● O ::
● eO *m*● : ● ● 0● ●:0 ● ●:0 :** ● O
ABSTRACT
This report describes a study which was carried out
primarily on ground-launched, single-stage, hydrogen-
propelled nuclear rockets. The missions considered were
flights into circular orbits and ballistic flights.
Particular emphasis was given to determine the effect
of missile trajectory, for a specified mission, on payload.
The types of trajectories considered were the powered-all-
the-way (PAW) ascent, the ballistic ascent, and the elliptic
ascent. In the PAW missions, the missile was flown from the
ground, along a trajectory that maximized payload, into a
prescribed circular orbit. The PAW results were then
compared, for a particular mission, with ballistic and elliptic
ascent calculations. The results show that most of the
missions studied were very sensitive to the type of trajectory
flown, thus clearly demonstrating the gains to be made by
$using a nuclear .,ocketmotor which has a racycle capability.
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
~y -- ..: . . . . . . . . . . . . ..O
●9*: ●:00● me● 9 : : : :0
● O we:● 00 ● ● 98 ●
‘.
Mission performance results have been obtained for
various single-stage nuclear systems, but with emphasis
on missions which require large payloads in orbit. Present
day technology indicates that a nuclear system having a
launch weight of-400,000 lb would be capable of placing
~apayload in excess of dg,()()olb into a S()()_micircular
orbit.
.
●
‘“”iii’$$+
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
.L x----+ --’--’-● - .*. ● *. ● m. ● .* .9
● ● **am*● o:lT e:* ● o9 ● ● *● : ● ● a
● ●:0 ● ●:- :*C●*
CONTENTS
Abstract
I.
II.
III.
IV.
v.
VI.
VII.
Introduction
Staging of the Rocket on the GroundA. Weights of ComponentsB. Mass Flow Rate, Thrust, Take-Off Weight
Trajectory Calculation through the Atmospherefor a Non-Rotating Circular EarthA. Evaluation of TgO/WB. Evaluation of DgO/Wc. Gravity Term
Powered-All-the-Way Trajectory OptimizationA. Derivation of Optimization EquationsB. Numerical Solution of the Boundary Value
Problemc. Results
Elliptic Ascent
Ballistic Ascent
Conclusions
References
Appendix Flow Diagram and Numerical h!ethod
● 0 ● OO ●:0 ● ●:. ●● 8● 0● m
-;5: *; : :“0
Page
3
9
131317
21232425
2929
3541
54
58
61
65
67
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
1.
2.
30
4.
5.
1.
2.
3.
4.
5.
6.
7.
Page
TABLES
Mission “Lob Shottf Results 27
Effect of Temperature on Vacuum Specific Impulse 50
Circular Orbit Mission Results for a Vehicle Havinga Launch iVeight of 72,000 Lb
Optimum Trajectory Mission Results
\Yeight Breakdown for Flight No. 3
ILLUSTRATIONS
Coordinate system for gravity-turn portion ofpowered flight
Trajectory history obtained from gravity-turnequations
Coordinate system used for trajectory optimizationportion of flight
Circular orbit altitude as a function of payloadplus reactor weight with the temperature takenas a parameter (results for PAW trajectories)
Circular orbit altitude as a function of payloadwith the temperature taken as a parameter(results for PAW trajectories)
Reactor plus payload in a given circular orbit asa function of vacuum specific impulse withcircular orbit altitude taken as a parameter(results for PAW trajectories)
Payload in circular orbit as a function of vacuumspecific impulse with circular orbit altitudetaken as a parameter (results for PAW trajector-ies)
-+
8 ;*“*
so ●9* ● b ● ●U
52
59
60
22
28
30
43
44
As
46
1
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
ILLUSTRATIONS (Continued)
Page
8. Circular orbit altitude in miles as a function ofmass ratio with the vacuum specific impulsetaken as a parameter (results for PAW trajector-ies) 47
9. Power density as a function of vacuum specificimpulse with the circular orbit altitude takenas a parameter (results for PAW trajectories) 48
10. Calculations showing the effect of tank stagingon payload, placed in a 100-mi orbit, as afunction of reactor exit gas temperature(results for PAW trajectories; launch weightused in calculations was 72,000 lb) 51
11. Circular orbit radius as a function of payloadfor a vehicle containing a working fluid ofhydrogen and methane (3 mole %) and operatingat an exit gas temperature of 1900°C (resultsfor PAW trajectories; launch weight used incalculations was 413,000 lb) 55
12. Total weight in pounds, placed in a 300-mi orbitas a function of thrustoff height in feet fora vehicle exit gas temperature of 2170°C, anda launch weight of 413,000 lb (results for acomposite trajectory consisting of a gravity-turn part, ballistic trajectory to apogee, andthen along an optimum path into a 300-mi orbit;results shown are for an optimum value of Bk) 62
● 0 *::oe 79+8. -.9*
● e ● .0 ● ** ● ob ● e* O*_ WIIJSSIFIED*9 *** ● ** ● ● O* .
● m “*- 6 “*- 00; ● ;
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● 9* ● ae **6● ** Oa. *P ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
I. Introduction—.
The purpose of this report is to describe a study
which was carried out primarily on ground-launch, single-
stage, hydrogen-propelled nuclear rockets. The performance
of a nuclear rocket containing a fuel made up of hydrogen
and methane (3 mole %) as well as a brief discussion of a
vehicle employing tank staging are also included in this
report. The missions considered in this study were flights
into circular orbits and ballistic flights. Sections I
and 11 are a review and extension of the work presented by
K. W. Ford.l The emphasis in Ref. 1 was to fly a given pay-
load a maximum distance. The emphasis here is to fly a
rocket from the ground, along a trajectory that maximizes
payload, into a prescribed circular orbit. The types of
trajectories considered were the powered-all-the-way (PAW)
ascent, the ballistic ascent, and the elliptic ascent. In
the PAW ascent the vehicle engine is operated continuously
until the desired orbit is achieved. In the ballistic
ascent the vehicle is carried to a summit (by means of a
propulsion and free-flight phase) which lies near the
desired orbit. At the summit, the vehicle must, in a second
propulsion period, produce the velocity increment required
for transfer into the desired orbit. In the well-known
Hohmann2 transfer ellipse (elliptic ascent), the vehicle
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
first attains circular velocity at a relatively low
altitude (taken to be 100 statute miles in this report) .
Subsequently, the vehicle is accelerated to the perigee
velocity of the transfer ellipse, at whose apogee an
additional short burst of power is required for entering
the satellite orbit.
In this work, the philosophy has been to consider in
detail the aspects of a particular mission problem only
if it is justified by present day knowledge. For this
reason, an accurate formulation of the equations for air
drag, air pressure, trajectory, and trajectory integration,
etc. , are used, whereas the equations that pertain to
rocket component weights have been simplified as far as
possible. The question of the type and weight of the
rocket motor, when the reactor weight is not available
from a detailed engineering study, has been avoided in a
given mission problem by lumping together the reactor and
payload weight. As more data become available, the
estimates of tank, structure, and other weights given here
will change, thereby necessitating changes in the results
given in this report.
The following few paragraphs will describe the
formulation used to solve a given mission problem in a
qualitative way. Details of the formulation are given
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
-bo ● *8 ● 00 ●:0 :00 :**
● 8● :: CC:*OO
● ● ● O
●:e* ● ● b* ● ** ● ● ** :** ● 4
in sections II to VI. Conclusions are given in section
VII.
Section II, Staging of the Rocket on the Ground, is
concerned with the determination of component masses and
sizes and propellant flow rate. In section II the
takeoff weight is written as the sum of 10 component
weights:
1.
2.
3.
4.
5.
6.
7.
8.
WL, payload plus nose cone plus guidance, given
W~2, hydrogen propellant weight
\YCH4F’ methane propellant weight
W~2, hydrogen tank weight, calculated from
hydrogen propellant weight
\YCH4T
, methane tank weight, calculated from
methane propellant weight
WH2 hydrogen structure weight, given as a fixeds’
fraction of W~2
\YCH4s’ methane structure weight, given as a fixed
CH4fraction of WT
~T~, weight of turbopumps and plumbing, written
as a function of pump discharge pressure and
volume flow rate
● ☛ ● ☛☛ 8*9 ● ● 90
W
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
4wliiMv● m ● ** ● *8 88* .b’8 ● *
● * 9*● *O:: W:*.● m.
● * :: : :*● m 9.:... ● ●we ●
9. ‘R ‘ weight of reactor plus pressure shell plus
gimbals, given
10. WN, weight of the nozzle, written as a function
of nozzle throat area.
The exhaust velocity can be calculated from the
chamber temperature and pressure. From this, the mass
flow rate and total mass can be calculated which will give
the specified initial acceleration.
Section III is concerned with the trajectory calcu-
lation through the atmosphere. The trajectory is vertical
for a time tk (kickover time), at which time the thrust
angle to the vertical is changed to f3k (kickover angle).
From the time tk until the rocket passes through the
sensible atmosphere (height h2), the rocket flies along a
gravity-turn trajectory (thrust vector parallel to
velocity) . The effects of air pressure and air density
are included in this calculation and are obtained from
an exponential approximation. Mach number and drag co-
efficient are calculated as functions of altitude from the
3equations in section III B of this report. The effect of
air pressure on thrust and the variation of the gravi-
tational force with altitude are taken into account.
In section IV the rocket is powered all the way (PAW)
from the height h2, along a trajectory that maximizes
● m” ● 9O ● 8 s ● i$-
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
-● ☛ ● 9* 8*9 ●:C :0*● 0
● ● ● *● : :* ●am*
0 :0●:00 ::
● 9** ● ●:0 :e*●*
payload, into a prescribed circular orbit. For this part
of the trajectory the magnitude of the thrust as well as
the mass flow rate were kept constant, The mathematical
formulation used in section IV follows closely the work
of L. Turner on minimum time of flight trajectories. 4
In section V the rocket is flown from the height h2,
along a trajectory that maximizes payload, into a 100-mi
circular orbit. The rocket is flown from the 100-mi
orbit to any other specified circular orbit by means of
a Hohmann transfer ellipse. Section VI gives a brief
discussion of the ballistic ascent trajectory, and
conclusions are given in section VII.
II. Staging of the Rocket on the Ground—.—.-
A.
1.
2.
3.
4.
Weights of Components
Payload weight, WL, given (includes nose cone and
guidanc~ in lb
Propellant weight (hydrogen), W~2, given in lb
~CH4Propellant weight (methane), F , given in lb
Hydrogen tank weight,
Q1(K + 2)!V;2 = ~ _ ~
(4/3‘( )
pT
+K — (1~H
- F)W;
2
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● a ●eo ●.. ●.. ... ●*● * ●●: : ●: :::0 ●
●● * :0 : :*
●m *.:*.. ● ● *9 ●
5. Methane tank weight,
~CH4 = Q2 (K + 2)
(1 (4/3‘( )
pTT - a) +K ‘CH4
(F)W:
The equations for the tank weights were derived on the
assumption of a particular tank configuration. The con-
figuration chosen was a tank of radius ~, with the
cylindrical straight section of length#T = K%, and
hemispherical endcaps. The over-all length of the rocket
is L = K% + 2%. The tank walls are made of steel of
constant thickness. In the foregoing equations,
PT =
PH =2
‘CH4 =
F
~TF
a
Ql
Q2
where
fs
=
.
.
.
=
.
steel density in lb/ft3 (value used was 494)
hydrogen density in lb/ft3 (value used was 4.43)
methane density in lb/ft3 (value used was 43.68)
weight percent of methane
total fuel weight (hydrogen plus methane)
fraction of tank volume left for air space
(ullage factor)
factor of safety
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
——● ☛ ●✚✎ :ea ●:= :8* 90
● ● m
● ● ●0: :090
● =● :**** ::
● ● *9 ● ● ** ● O8 ● *
p:2 = hydrogen tank pressure in psi (gas overpressure
plus hydrostatic head)
PCH4 .T
methane tank pressure in psi (gas overpressure
plus hydrostatic head)
a = yield strength in psi
In this work K = 10, a = 0.03, fs = 1.39 and was taken
from LA-1870,5 and o = 150,000. The value used for the
overpressure in the tanks was 25 psi (based on the Atlas
design), the value of the hydrogen hydrostatic head was
assumed to be 10 psi, and the value of the methane
hydrostatic head was assumed to be 35 psi.
6.
7.
8,
Hydrogen structure weight assumed is
\v~2= 0C15 W~2 in lb
Methane structure weight assumed is
WCH4s =0.15 W~H4in lb
.
The total pump weight (W;) is
Since the present state of hydrogen pump development is
in its infancy and no methane pump development is in
progress, no attempt was made to estimate separate pump
weights. What was done was to assume that
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ✎ ● ✘☛ ● .a ● . . .** ● *99 ●●: ●
●●: :::0. ●
● * : : :0. ●* ●.:9:0 ● ● ee ●
Cp(l - F)iv:(Pd)1/2\YT_P—
W:2 .P~
2
(1)
since only problems containing small admixtures of methane
were considered in this report. In Eq. ‘1
~TF = total propellant flow rate in lb/see
~H2 = hydrogen propellant density
‘d = pump discharge pressure in
and
cP
= 1.28 (see page 287 of Ref.
lb/in.2
3)
9. Reactor weight plus pressure shell plus reflector.
No attempt was made to calculate reactor weights when
detailed engineering data were unavailable. When this
was the case, the calculations were performed by lumping
together the reactor and payload weights.
10. The nozzle weight is
wN=where
‘t =
CN =
CNAt
throat area in in.2
6.8 (the value used for the nozzle coefficient
is thought to be conservative) 6
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ●:O :00 ●:* :00 ● 0●
● O:e::* ::●c: ::
9 ●:9 : ●:0 :0s● 0
B. Mass Flow Rate, Thrust, Takeoff Weight*——— .—. — —— ——
1. Exit pressure. For a gamma law gas and adiabatic— —.—.
expansion, the ratio of exit area to throat area is related
to the ratio of exit pressure to chamber pressure by
(see Ref. 7, page61)
$ =(kf,)(k-lqy-’{(2;)[1 -(*yk-1)’k]}l’2(2)
where k is the ratio of the specific heat at constant
pressure to the specific heat at constant volume. In this
problem the area ratio is specified, as is the chamber
pressure Pc. Hence this equation yields a value for the
exit pressure Pe.
2. Exhaust velocity. The exhaust velocity for a—.
perfect, infinitely expanding nozzle is
v“ =e
where
i% = the universal gas constant
B = 2782 ft-lb/lb-mole ‘K
Tc = the chamber temperature in ‘K
*Portions of section B were taken from an internalmemorandum by K. 1’?.Ford, a LASL consultant.
.* ● ☛☛ ● ☛☛ b ● m. ●
(3)
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
.__.. —“
● ✎ ● oo . . . . . . . . . ● ,● m ●:
b: .: :::0 ●
● 6 : : : :0● m ●e: ● ea ● ● 6* ●
go 2= a constant = 32.17 ft/sec
M = the average molecular weight, defined byav
Mav =
where
Y-li = mole percent of constituent i
‘i= molecular weight of constituent
The actual exhaust velocity is
vcv:cNL[,_(~y’-l’’1;2’2
(4)
i
(5)
‘here CNL is a nozzle efficiency factor, set equal to 0.97
for the problems discussed in this report.
3. Effective exhaust velocity and specific impulse.—
To the exhaust velocity must be added a term due to finite
exit pressure and finite air pressure, which we call the
“pressure velocity,”
where Pa is air pressure and C*, the characteristic
velocity, is given by
(6)
● 6;**. WO*W. .9* ● 9 ● ● .
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
[(k%)~Tc)/Mav]1/2C* =
k [2/(k + 1)](k+l)/2(k-1)
The specific impulse is
(Ve + Vp)I .—Sp = ——g
o
(7)
(8)
where Ve + VP
is the effective exhaust velocity. Because
of the flow separation in the nozzle, the ratio Pa/pe
cannot become arbitrarily large. In this problem we limit
the ratio to 3. If Pe is calculated to be less than Pa/3,
we arbitrarily replace (1 - Pa/Pe) in Eq. 6 by -2.
4. Mass flow rate. The effective exhaust velocity and
given desired initial takeoff acceleration, goao, specify
the mass flow rate,
~T = $@o(l + ao) = Wo(l + ao)
F (1 - E)(Ve + Vp) (1 - 3)(ISP)(9)
where % is the fraction of the propellant used to drive the
pump. This fraction is assumed to be exhausted at
negligible velocity.
5. Throat area. The throat area is given by——
● ✎ ● -w .m. ● ● 00 ●
(10)
● ee9● * ●: : * ! ‘o”::
●● * ●
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
80 ● *9 ● ** ● 09 ● oe ● *90●O.: ●: 9: :s
●:: :: : :0● 0 90:●@* ● ●** ●
6. Reactor power. The reactor power in Mev is given
by
‘R = CRl$ AT (11)
where AT == the temperature drop of the gas through the
reactor, in ‘C
CR= 7.21 x 10-3 megajoules/lb ‘C
The alteration of specific heat due to admixed CH4 and
the question of dissociation and recombination are not
taken into account.
7. Launch weight equation. An explicit formula for
total takeoff mass WO may be arrived at from the formulas
given above, and is
W. =
,,L+wR+,,,f;:;:+K)~*15([Q2,Qll::j1}
go(l+-ao)
[
(l-F)CpPdl’2 CNC *1- +
1
(12)
(l-m)(Ve+v;) pH (Pcgo)2
Once WO is determined from Eq. (12), all component weights.
can be found as well as the mass flow rate W,. The total
burning time, if all the fuel is used, is
●“: “;”$0 “:” ;“” ;“:● ...*. .bm
(13)
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
. . . . . ● *O 9*9 ● ** ● *● ● m@ ● O
● :000:000● 99●:*O ::
● ● 00 ● ●:0 :9* ●*
where a is the fraction of unused propellant at burnout
(holdover) .
With a slight modification of Eq. 12, the equations
given in this section can be used to determine the
performance of a chemical system. To do this, Eq. 1
Tmust be changed so that Wp is the sum of two pump weights,
which
III.
in turn introduces an additional term in Eq. 12.
Trajectory Calculation through the Atmosphere for a—— .—
Non-Rotating Circular Earth—_
For this part of the flight the rocket is flown
vertically for a time tl{ (kickover time), at which time
the thrust angle to the vertical is changed to Bk
(kickover angle). From the time tk until the ro~
passes through the sensible atmosphere, the rock(
along a gravity-turn trajectory (thrust vector p:
velocity) . The equations of motion for this par”
flight (see Fig. 1) are
(T - D)gO+= - g COSB
w
i=- (V sin13 sinf3
- g— )\R v
i = v cosf3
● 9 ,*8 ● ** ● ● *9 ●● e
::●00: : zi 1 ‘.”● m
● 0 ●.: ●:0 ●p;.+c”& - -- ““”--
set
t flies
rallel to
of the
(14)
<15)
(16)
(17)
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ●O: ,:a ● m. . . . . .9* ● m
● * ● .:::00 ●
● * :: :0● O ●.: .:0 ● ●:0 ●
Fig. 1 Coordinate system for gravity-turn portion ofpowered flight
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
90 ● am 9*9 ● *9 :9* ● *● ● m
● - : co ● O ::● a :0●:*U ::
● ● *m 0 ●:0 :.* ● 0
where
V = absolute value of the tangential velocity
B = angle the velocity vector makes with local vertical
R = distance from center of earth to missile
0 = angle the radius vector makes with y axis
T = rocket thrust in pounds
D = drag force in pounds
In order to solve this set of simultaneous, nonlinear,
first order differential equations we need to obtain
TgO/W, DgO/W, and g in terms of the variables of
integration. These quantities will now be evaluated.
A.
The
changing
specific
Evaluation of TgO/W
specific thrust (TgO/W) is a function of W(t) and
air pressure. The effect of W(t) is to cause the
[ 1-1thrust to be proportional to l-(&vo)t ,
(18)
and the effect of changing air pressure causes the specific
thrust to be proportional to (Ve + Vp)/(Ve + V:). The
value of V isP
v; (1 - J?a/pe)Vp ‘——-——
(1 - 14.7/Pe)
except that the denomina-tor and/or the quantity in
parentheses in the numerator are arbitrarily replaced by -2
if either is calculated to be less than -2. Thus TgO/W
● e ● ● ● ● 00 96
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ✎✎✚ ✎☛✎ ● ✎ ✎ ✎ ✎ ✎ ✎ ✎90 ● *
9* : ●:::0 ●
● * :: :9* ●0: ●.* :0
● ●:0 ●
can be written as
Tgo ( )[Tgo (Ve + Vp)—- _w w o (Ve + v;) ,()].T -1
1- wF/wo t
where (Tgo/W)o is the initial specific thrust and is
gO(l + so). The value of Pa was obtained from the equation
Pa ~ 14.7 e-(h/22,800)
where h is the altitude in feet (see Fig. 1),
B. Evaluation of DgO/W
The equation for the specific drag (the value of D
was obtained from page 373 of Ref. 7) is
W.[ 1‘gof#&a (h)V2
—=w(t)
where
‘T =
Pa =
go =
v=
w(t) =
8W(t)
tank diameter in ft
air density in slugs/ft3
32.2 ft/sec2
speed in ft/sec.-
‘o - W;t
The value of pa was obtained from the equation
pa(h) = AT e- (h/22,800)
(20)
(21)
(22)
● m. ● **i Om -● O ● 9* ● 8 . .*
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ● 00 noe 0:0 :00 ● *● ●
● : ● - ● m ::
W* :0 ● *●:*9 ● * Oc
● ● em ● ● 9* ● 9* em
where AT = 0.003 and h is in feet. The formulas used to
obtain the drag coefficient are
CD = 0.37 if M < 0.9
CD = 0.60 + 2.3(M - 1) if 0.9 S ~ ~ l.l
CD = 0.30 + (0.60/M) if M >1.1
where M = V/c = Mach number. Sound speed, c, is represented
by
c = 1120 - 0.00414h if h < 35,000
c . 975 ft/sec if h ~ 35,000
The value of c should increase again at very
altitude, but by this time, the drag is small,
accurate value of c is not important. It iS
the relative slope of the curve represented by
ft
ft
high
and an
felt that
these
equations is correct, but the absolute values of the
numbers to be assigned to the ordinate are in doubt. The
coefficient fD is introduced into the set of input
parameters in order to facilitate easy changes in CD as
better information on CD vs M becomes available. (For
the problems in this report fD was taken to be 1.)
c. Gravity Term
The gravitational
(R
acceleration is
)2
(23)
● omeo ● ** ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ✎☛✚ ● 9a ● om . . . . .● 08 e**
● S: ●: ●
● b ● *●
● *9
: :0● * ●0: ●:0 ● ●:0 ●
where R the radius of the earth, is 2.0908 x 10e’7 ft.
1. Solution of the equations. Having Tgo/W, Dgo/W,
and g in terms of the variables of integration, values of
13,V, R, and 0 were obtained as a function of time by
numerically solving, by means of Runge-Kutta, Eqs. 1
through 5. The calculations were carried out on an IBh!704
computer. The program
appendix.
A possible flight
possibility of nuclear
for this problem is given in the
demonstration mission to prove the
rocket propulsion would be to 10b
a vehicle to an altitude ofe500 to~1000 mi and then let
it impact a few hundred miles from the launch pad. A
reactor operating at a temperature of 2000”C and running
at a power level of~1000 Mw, Kiwi C design, has the ability
to generate enough thrust for this mission. Using the
equations developed in section 11, the launch weight of
such a vehicle was found to be ~41,000 lb. The vehicle
component weight breakdown is given in Table 1.
trajectory history, obtained from the equations
in this section, is given in Fig. 2. The input
The
developed
parameters
used in working this problem, and which are common to all
problems discussed in the report, are also given in Table
1.
● om ● *9 ●me 8se ● oo ● ● ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
9. ● *. ..9 ● .* ● m. .9
● **a@● 00009 * ::
● m● :● ●:0 :
9 **9● ● e●:0 ● ae ● 8
TABLE 1
Mission ~fLobshott’Results
Launch weight
Flow rate
Reactor power
Reactor exit gas temp
Pump and turbine weight
Nozzle weight
Structure weight
Tank weight
Reactor weight
Fuel weight
Holdover weight
Tank diameter
Ratio of over-all lengthto diameter
Velocity at burnout
Maximum height
Total burning time
Distance from launch padto impact
Payload
Total time in air
Holdover 0.01 Fue1to drive pump
Ullage 0.03 Takeoff acceleration
40,600 lb
79.3 lb/see
1140 Mw
2000”C
1000 lb
400 lb
600 lb
2100 lb
9000 lb
27,000 lb
400 lb
11.3 ft
6
14,050 ft/sec
1050 mi
341 sec
300 mi
100 lb
1685 sec
fraction used
Ratio of length to 6 Effective k of hotdiameter hydrogen
Pump discharge 1500 psi Nozzle exit area topressure throat area
Chamber pressure 1070 psi Nozzle eff factor
0.05
0.35 go
1.35
25
0.97
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
.
●✎
●☛
☛4,0
●ob
..0.*
●m
●0
e:
:●:00
::*O●
.:
::0
●O
●0
:s:.
●●
e*
●
II
<1
fI
11
III1
II
II
II
1I
l&\
a
1i-
0ml
#X
1-J
‘lH~13H
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
—.-–. –*9 ● ** ● O* ●:* :*O ● 0
● 9● : ● O ● * ::
:0 : ● 0● : :00● ● 00 : ●:Q ● *9 ● *
Iv. Powered-All-the-Way Trajectory Optimization
A. Derivation of Optimization Equations
The direction of the thrust is programmed in such a
way as to minimize the time required for the rocket to fly
from the top of the atmosphere (h2) to the prescribed orbit.
During this portion of the flight both ~Vand ISp
are kept
constant. Since both ~ and l~p are constant, minimum
flight time means maximum payload. The required mathe-
matical formulation will now be derived.
Let R and O be polar coordinates of a point in space
with respect to an inertial coordinate system whose origin
is at the center of the earth (see Fig. 3) . In Fig. 3, 13
is the angle the velocity vector makes with the local
vertical, Y the angle the thrust vector makes with the
local vertical, and h the altitude of the rocket above
the surface of the earth. At time t2 a missile with mass
W02 is at (h2, f32)and has velocity V2. It is flown from
h2 and arrives at the prescribed circular orbit after a
time t’ = t3 - ‘2’ which is unknown. For this portion of
the flight the time scale was shifted an amount t2 for
convenience in the integrations. To obtain the actual
flight time, t2 must be added to t’. It is desired to
find functions qR and ~o, the specific thrusts in the
direction of R and Q (see Fig. 3), which minimize t’ under
● ☛ ● *O *** ● ● *O ●
‘w
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ 9*8 ● 9* ● ** ● ** ● *● * ● m
●00: : ●: ●● me :9. : : :0
● * ●.: ● e* 8 ●:* ●
A
.
Fig. 3 Coordinate system used for trajectory optimizationportion of flight
● ☛☛ ● ●✚☛ ● *C ● 0
●’.●“w :: 0!:. . . -. . .
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ● O* ● ** ● *O ● 00 ● m● ● 0 ● *
● .* ...:::99 **8●: ● *● ●:*: ●:0 :00● 9
the given constraints. The functions ~R and To satisfy
(24)
from t= Otot= t’, after which they are both zero. The
value of t’ can be determined for a specific orbit altitude
from a knowledge of qR and qO.
The equations of motion are
. . .2R- RO+~=~R
R
and
(25)
(26)
where
it=2
goRe
● ✎
Letting U = R and L = R2Q leads to the following set
of equations:.
L2 IiiJ-n+=-qR=o=v2
RR
L u=o=@3
plus the equation .
()
2goWIsp
7:+7:- ~ =0=44
o
(27)
(28)
(29)
(30)
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ✎ ● ☛☛ ● 90 ● O* ● ** ● 0● 9 ● m●00: : ●: ●9** :● m : : :0
● 0 ●0: ● 00 ● ●:O ●
Now we wish to fly the missile from height h2 to height h3
in the minimum amount of time, thus expending the minimum
amount of fuel. To do this we minimize the time subject
to the above
conditions R
conditions R
differential constraints and the initial
= ‘2’ U=u2’ L = L2 and the final (or end)
= ‘3’ u = ‘3’ and L = JJ3’‘here L3 ‘s ‘he
angular momentum necessary to have a circular orbit of
radius R3. The integral to be minimized is
where
i= 1 to 4
(31)
Now in order that 81 = O, the function F must satisfy
the Euler-Lagrange equations
(32)
d
(“)
dF aF=o-—z dyi ayi
and in addition the transversality condition 8 at t’.
condition is
where dt and dyi pertain to the final curve (circular
(33)
This
(34)
orbit) and the coefficients of dt and dyi pertain to the
.**● .00● m. ● m
●** b ●●
-q ::.:!:3 .9 .-
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
—.- — -- ~.* .*. ● ✎☛ 9.* .** ● m
● ● **● : ● 0 ● 0
● 9::
:● :● 0
:● ●:0 : ● *●:0 ● *O . .
path leading into the final curve. Substituting F into
Eq.33 leads to the following set of equations:
‘3= % - ‘2($ -5)=0
● u L‘1 “ Al; + 2A2;2 = 0
i2+A3=0
‘2-2qRa4=”
‘1-2qoA4=0
Eliminating X4 from Eqs. 38 and 39 and making use of
Eq. 30 yields
yR .
and
(35)
(36)
(37)
(38)
(39)
(40)
(41)
Equations 40 and 41 show that X2 is a direction number
along the radius vector and that A is a direction number1
normal to the radius vector. Substituting F into
Eq. 34 and writing the equation of the orbit as a function
● ☛ ● O9 ● *9 ● ● 00 .● *.*. . . .
diid?ib● m*..
● 9*● ** ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
.● ✎ ✎✠✎ ● ✎ ✎ ✎☛☛ ● ☛☛ b.
● 0●e; 9: .: :*
● * ● O*be ● :.
● 0 ●0:●:0 ● ●:0 ●
of t, namely, R = C (a constant), L = C, and U = O, yields
[[F-(>)+%+%]dt}tt‘o (42)
and since @i = O, R3 = O, Eq. 42 becomes
k+‘+ =1 (43)
.Since U = ~R and ~ = R’qQ at t = t’, Eq. 43 can be written
as
(44)
which is our transversality condition.
From Eqs. 40, 41, and 44 the equation for the final
time (t’) in terms of the directional components of the
thrust is
‘t =(;)- ‘OISP [a:+ ,:)1’2(45)
and since t2 is known, the actual flight time to enter
into the prescribed circular orbit is t3, where t3 ==t’ + t2.
For convenience we now group the equations to be
solved together. They are
~-R~e=O
2 IiiJ-A+--qR=o
R’ R2
i-u=o
● ● *9 ● ● a* ● e* ● *● 0m●eeeo:
● m ● ea ● ● ● ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● *99*● **me** ::
9***● :● *
● ●:C : ● *●:0 :Oe ● 0
. 79 3L2 2X‘3+ A1—R-k2~-~=0
. ‘1 ‘2-u-+ 2~=o‘1 R R
i2+A3=o
The boundary conditions at t = O are R = R2, L = L2,
u= U2 and are given in section III (obtained from the
solution of the gravity-turn equations) . The boundary
conditions at t = t’ are R = R3, U = O, L = L3 = (%R3)1/2.
In the above set of equations we wish to solve for L, U,
R, Al, A2, X3 as functions of time.
B. Numerical Solution of the Boundary Value Problem—
To obtain a numerical solution to the above boundary
value problem, a suitable first guess of Al, k., A.
at t = t’ must be made.
with an IBM 704 computer
guess for the l’s is
L~. a
Examination of results found
has shown that a suitable first
“T’02 = ‘O - ‘F ‘B
‘1= .
(2.8W Ve+vP) (
2.8W Ve+VP)
A2=W -2 1
0.71A3=ve+ v
P
● ☛ 9** ● 9* ● . . . ●9**O● 0●0.: : .~5~ :.”● *** ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ✎ ●☛✚ 9:* ●0: ●:. ● 0● . ●
● e*ma ● m ●● e :● e : : : :9
● O ● ** ● ** ● ●:0 ●
If this leads to a negative t’, the machine program
automatically selects another initial set of A’s from
among a group of five “built-in” guesses. If all of
these fail, the machine prints out “T is negative” and
the problem is terminated at this stage of the calculation.
To clarify notation the X guesses will have a numbered
superscript starting with zero; the first guess of Al,
‘2‘ A3 at t = t’ is A;, A;, A;.
Using the first guess for the A’s (k;, k;, A:) along
‘ith ‘3’ ‘3’ and ‘3’ start at t’ and integrate back through
the set of differential equations, by means of Runge-Kutta,
to obtain R(0) = RO, u(o) = Uo, and L(0) = Lo. ‘et all’
‘2s and ’31 be the final values of these functions in the
correct solution. The correct values of R, U, and L at t
= O are R(0) = R. = Ru, U(0) = U. = U2 and L(0) - Lo = L2,
A systematic method for generating additional sets of A’s
such that
Ri - R. ~ CR
Ui -Uoseu
Li ‘LO<CL
will now be given. In these equations i represents the
ith set of A’s used and ~R, Cu, and GL are prescribed
9** ● 9:* ● *O 90
●°0● ;3qe : ;0 : ;
●--- -...
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
—-● ✘ ● ✎ ✎ ● 9O ● 0. ● ** .0
● emem● m*m*OO ::
● 000● :9*
●● *●:0 : ●:0:00● O
errors in radius, radial velocity, and angular velocity.
We now relate the X’s at t = t’ to the values of L,
U,andRatt= O by the equations
Lo -LO= fl(A;,A;,A:) - 1)‘1(A119A219 31 (46)
U“ -Uo= f2(A;9A:,A;) - ‘2%1’A21’A31) (47)
- all) + a22(A~ - A21) + a23(#= a21(A~ - A31)
RO - R. = f3(A:,a:,A:) - (48)‘3(All~A21~A31)
a31(A~ - kll) + a32($ - X21) + a33(#. - a31)
where the right hand side of these equations represents the
first order terms of a Taylor series expansion of
fl(g, o‘2‘ A:) about fl(All, A21, 131) and so forth.
Now we continue to generate sets of X’s, subject to
the condition that
u’02t’=— - goIspi [F:)2 + (A:)2] 1/2
until
(49)
9* ● ** ● 9O . .*. ●
w
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
‘2PA31) = o
’219 A31) = o
The procedure used to satisfy Eqs. 49, 50, and 51,
was the following. Equations 46, 47, 48 are first re-
written as
Lo - Lo = Allh; + a12h~ + a13h;
U“ -Uo=a 121h; + a22h; + a23h3
RO - R.1
= a31h~ + a32h2 + a33h;
(50)
(51)
(53)
(54)
where
~o 1
1 - ’11 = ‘1
o 1‘2 - ’21 = h2
o‘3 - ’31 = %
In Eqs. 52, 53, 54, the quantities h:, h:, h:
represent a correction in the choice of the first set of
A’s,000namely, hl~ A2~ A3. The second set of X’s chosen is
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
X:=A~-h:
1 k’ - h:‘2=2
lo_hl‘3=A33
(57)
1and can be determined once hl, h;, h; are known. The values
1‘or ‘1’
h:, h; are determined from Eqs. 52, 53, 54 once the a
coefficients are known. The method for determining the
coefficients in Eqs. 52, 53, 54 is as follows.
Change X? slightly to x; - AA1, and use this new set
o 00of a’s, namely~ 11 - AA1, A2, X3, to obtain the time of
integration (t’) from Eq. 45 and then integrate through the
differential equations. This yields
U’ + AU - U. = -a21Ak1 + a21(A~ - All)
RO+AR-Ro= -a31Ak1 + a31(A~ - All)
● 9 .*b ● *Q b **9embu ● ● 4“*● * ●●e*:e ●: :39.0● *9* am:9:...:G:..-
a!ummub● 0000 ●0: ●* “
(55)
(56)
(58)
(59)
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
to .*: 0:0 ● 9* b:. *CO* ●● 9*** ●:**● **b:*b. :0
co ●0:●:0 ● ●:O ●
Subtracting Eqs. 46, 47, 48 from Eqs. 58, 59, 60 yields
a21 = - AU/AA ~
a31 = - AR/AAl
The other coefficients are obtained by varYing x: and
o 11‘3 “
The new set of A’s, namely, A:, ‘2‘ ‘3‘ are used to
obtain a new t’ from Eq. 45. With this set of A’s we
integrate through our differential equations, starting
at t = t’ and integrating to t = O, obtaining a new set
of f’s which are
f2(a:, 1 A:)‘2 ‘= U1
Starting with this set of f’s, the routine given above is
used to obtain the new set of a coefficients. In
obtaining these the same set of AA’s is used. Then a new
set of h’s is generated, which are h:, h;, h;. From this
set of h’s, a new set of k’s is constructed, which is
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
** ●:O ● *9 ● ** ● ee 90● *9* em
● 9** ● **8● O :. ● o● :
●**●:0 : ●:. :*O ● 0
~2=A1-h2111
212‘2= A2-h2
A;= X; -h;
This procedure is continued until
Ri - RO ~ CR (61)
Ui-uoseu (62)
Li-LOSeL (63)
where eR’ ‘u’ and eL are prescribed errors in radius,
radial velocity, and angular velocity.
At this point the optimization equations were combined
with the gravity-turn equations and coded for an IBM 704
computer. Details of the code are given in the appendix.
c.
1.
missiles
will now
Results
IJydrogen system. The results for single-stage
having launch weights of 413,000 and 72,000 lb
be given. In these results it is assumed that,
for temperatures >1500”C, one is flying a nuclear rocket
which has a corroding reactor or that the reactor has
graphite-loaded fuel elements which are protected with
niobium carbide. (See following section.)
●* ●W8 ●** ● ●ar ●
::00
:!
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
*h
● 9 ● .* ● -* 99* ● *. ● *9** ● e
9*** : ,:00● 0 ●
● * : : :0 :6● 0 91S9 ● oo ● ● 90 ●
Figures 4 through 9 give the final results obtained for
a missile having a launch weight of 413,000 lb. Figure 4
gives circular orbit altitude as a function of reactor
weight plus payload with the temperature as a parameter.
To convert the results given in Fig. 4 in order to obtain
circular orbit altitudes as a function of payload with the
temperature as a parameter requires reactor weights which
can only come from a detailed engineering study. Since no
detailed engineering data exist for reactors having power
densities of 0.5 Mw/lb and associated temperatures in
excess of 1500”C, we assume that reactor weight can be
expressed as (see page 290 of Ref. 3)
‘R‘R = 10,000 + 2000 —
Tc(64)
where
‘R = the weight of the reactor plus pressure shell
PR ==the reactor power in Mw
Tc = the gas temperature at the exit of the reactor in
‘c
Equation 64 is only used in connection with missions which
have a vehicle launch weight of 413,000 lb. These missions
require reactor powers which vary from 9000 Mw to 16,000 Mw
and exit gas temperatures in excess of 1500°C. Equation 64
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
Wiu
liik●*
●:0
●9*
●:0
●*.
●.
●●
●*
●*
:9●*,*
●e
:●
*9:
:●
●*
.:@:
●:0●
98
●9
n
ml
Q*.mCQ
00
t+
00
00
00
:g
CJ
0ON
m—
saw‘3anm7v
●m●**
●**●9*9
●.
●.’.,
:::
9**9
““k&4i4km
Aramu
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
●✎
●☛
☛●
☛☛
9e.
..
.8*
8*
9*
●00::
●:00●
m●
.::
::
:=
—
.
oC&
smw‘~anm.v
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
●●
✎☛
●9*
●8e
●**
i*-”-”-●
●●
O**
●0
:0●
**O●
9:
●:
:::
●●:0
:b:.
●**●
O
I[
II
II
u)
w-1—
———
oco
oto
o*g
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
mu
—
II
I1
II
II
II
~o
0a
om
eoN
#X
al‘avolA
~d
@c/lcd
du):“%-P
*
bGTI
lx
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
H
&l-i
II
Io0m
S311W
●☛
●☛
✘●
98
●*
::●
●:
●::
.0●
.:.:.
@?
?i@
mr
●*e
**●0:
●0
o0
0mu-i
CJ
ti
A+w-l
m
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
●✎
●☛
☛●
O9
●**
●**
be
90
●9
●00:
:●:00
●O
*m●
●*
:0
:0
90
●*:
●:9
●●**
●
o0000
CJ
Um
mo-—
Iu)u-1s
81/MW
‘AllSN3ak13MOd
+&
3:
hf+.tl
0$!
cdOd
m
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ● O* ● *8 ●:0 :00 ● *● ● *● *:**:* ::
● 8
● : ::
● ●:0 : ●:D:00● 0
is used to obtain the results given in Fig. 5.
The only high power density,high temperature reactor
for which a detailed engineering design exists, using
hydrogen as the propellant, is the Condor reactor.9
The weight of a Condor reactor, operating at a temperature
of 1500°C and at a power level of 9000 Mw, is 22,800 lb.
This represents a power density of-O.4 Mw/lb at a
temperature of 1500”C. Substituting the Condor values
for PR and Tc into Eq. 64 yields a WR of 22,000 lb;
thus Eq. 64 is essentially anchored to the Condor results
at 1500”C0 Whether or not the reactor weights given by
Eq . 64, for power densities greater than 0.4 Mw/lb and
associated temperatures in excess of 1500”C, are possible
with present day technology depends on forthcoming detailed
engineering studies.
Figure 6 gives the reactor weight plus payload as a
function of vacuum specific impulse with the circular orbit
altitude taken as a parameter. The relationship between
the gas temperature, in degrees centigrade, at the exit of
the reactor and the vacuum specific impulse is given in
Table 2.
● 0 ● ea ● *9 ● ● ** ●
WiiiilQ● *O** ● ** ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
4
● . . . . ● .* ● 99 .m. ● *
● me ● *● *O* : .:eo● * ●● D :* ::0
● m S-:● mo ● ● mm ●
TABLE 2
Effect of Temperature on Vacuum Specific
Tc, “C Isp)vac
1900 761
2170 807
2500 860
3000 934
3500 1003
Impulse
The results given in Fig. 7 were obtained from Fig. 6 by
making use of the previous relationship, Eq. 64, for
reactor weight. Figure 8 gives circular orbit altitude
as a function of mass ratio (launch weight/burnout weight)
with the vacuum specific impulse taken as a parameter.
Figure 9 is a plot of power density as a function of vacuum
specific impulse with the circular orbit taken as a parameter.
The power density 10 is defined as the ratio of total jet
power to the weight of the core, reflector, pressure shell,
controls, and payload.
Figure 10 gives the results for a vehicle having a
launch weight of 72,000 lb. The component weight break-
down for this vehicle
in Fig. 10 is a curve
made by tank staging.
is given in Table 3. Also included
which demonstrates the gains to be
No attempt was made to do an optimum
-.W. 0 ● *
m!lodi#● ● . ● ● ● ● .“8● D ● ee ● ● ● ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
—-..
.:0:0
6S
:*:-
:*0●●
=:.::.
::●
●:
●.*
●●
:*●
●:0
:00●.
II
II
c)z—
G$(n
)>D000C9
N~a
lc)oNl-:Id
a0
.0R
IN0
—0
—iii
II
I0
I0
I
00
00
0s!
00
00
00
00
00
0g
0W
Im
lto
g;
‘avOIA
;d
o0Inml
o0uml
u3t-4aUJa~*
odG.4k
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
. . ● me ● ** ● -. ..a 9*● 0 ● 0.OO::O: ●
● e :● 9 : :0 :0
● 0 9** ● O* ● ●:0 ●
TABLE 3
Circular Orbit Mission Results for a Vehicle Having aLaunch Weight of 72,000 Lb
Launch weight
Flow rate
Reactor power
Reactor exit gas temp
Pump and turbine weight
Nozzle weight
Structure weight
Tank weight
Reactor weight
Fuel weight
Holdover weight
Tank diameter
Ratio of over-all length todiameter
Payload weight
72,000 lb
141.5 lb/see
2214 h!w
2170”C
700 lb
400 lb
1000 lb
4200 lb
8000 lb
53,100 lb
600 lb
14.5 ft
6
4000 lb
● *m ● 00 ● **● * ● *8 ● ● ● ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
. -—● e ● eb 9,0 900 :00 ● 0
● bob
c9:0 ● e ;;● :● : :
●● 0●:0 : ●:* ● C.O se
tank-staging calculation. The calculations were done by
merely dropping a tank when the rocket reached an altitude
of 200,000 ft. The weight of the tankage dropped was
equivalent to the tank weight required to contain the
fuel expended in reaching staging altitude. These
calculations were performed to demonstrate that tank
staging, if mechanically feasible, is quite advantageous.
2. Hydrogen-methane system. Experimentally it has—
been shown that graphite, at the temperatures of interest
in nuclear rocket propulsion, is subject to severe
corrosion by hydrogenous working fluids; and in order to
achieve a useful long life of even the few minutes required
by a rocket engine, some means of protecting the graphite
surface is required.
Several approaches to this problem have been studied
at LASL. One approach is to render the working fluid
neutral towards hot graphite by the addition of some
carbon-containing material such as methane, ethane, etc. ,
to the hydrogenous working fluid. Another approach, which
is showing promise, is to coat or line the surface of the
graphite with niobium carbide. Results indicate that a
working fluid of hydrogen and methane (3 mole %) at a
temperature of 21OO”C is possible
11corrosion. Without the methane
without graphite
the temperature of the
● ☛ ● ☛☛ ● 00 ● ● ** ●90
:: ●●0s:0 .: ~3:,:● amm
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
+
● m ●0: 9** ● .0 ● *9 ● 9● 0● 006: ●●: :sbe ●9* : :- : :0
●8 ● .3* 900 ● ● 00 ●
working fluid, for no graphite corrosion, is~1500° C.12
Preliminary experiments on coating (or lining) the graphite
indicate the possibility of a hydrogen working fluid
temperature of~2500°C.13
The technology of protecting the graphite-loaded fuel
elements with niobium carbide has advanced to the point
where the consideration of a working fluid of hydrogen-
methane is no longer attractive. An example of the
performance of a nuclear rocket using a working fluid of
hydrogen and methane (3 mole %) is given in Fig. 11 for
an exit gas temperature of 1900”C.
v. Elliptic Ascent
In these calculations the vehicle was flown from
launch pad to height h2 by means of a gravity turn and
was then powered from h2 into a 100-mi circular orbit in
a manner that optimized payload. For purposes of
discussion this 100-mi orbit will be referred to as orbitl .
The choice of the perigee orbit at 100 mi was due to
practical considerations. 14 The vehicle was flown from
orbit 1 to various other circular orbits, all of which
were at altitudes greater than 100 mi. The equations used
for obtaining satellite payloads, for the elliptic ascent
trajectory, will now be given. For this discussion we
consider the flight of a vehicle between orbit 1 and
● ● *9 9 9** ● 00 ● O
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
m. ● . . ● a- ● O- ● me .9
● ● *** ● ,
bee, ● 009● * :0 ● e
● :O b*
● ● 00 : ●:C :00 ● O
I I I I I I I I I I I I
I 1 I I I I I I I I I I I2 4 6 8 10 12 14 16 18 20 22 24 26
PAYLOAD, LB X 10-3
Fig. 11 Circular orbit radius as a function of payload fora vehicle containing a working fluid of-hydrogenand methane (3 mole %) and operating at an exitgas temperature of 1900”C (results for PAWtrajectories; launch weight used in calculationswas 413,000 lb)
● 0 bob *b* ● ● b*● * ●**
::*O*: : 55: : “.*● 9*
● * ●*b ●**●** ●*9●*
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
.● ✎ ● ✎☛ .3. . . . . .9. ● *
● e 9*●e.: : ●:*O●::* : : ::0
●* *ee ● @* . ● 8* ●
orbit 2, where the radius of orbit 2 is greater than orbit
1. The velocity increment required to transfer the rocket
from circular orbit 1 to an elliptic orbit, with apogee at
circular orbit 2, is
where
v = the vehicleP
orbit
vc1
= the vehicle
(65)=V-vclP
velocity at perigee in its elliptical
velocity in circular orbit 1
The velocity increment required to transfer the vehicle
from the apogee of the elliptic orbit into circular orbit
2 is
AV2=V-VaC2
where
Va = the vehicle velocity at
orbit
v = the vehicle velocity inC2
(66)
apogee in its elliptical
circular orbit 2
The equation for the velocity of a vehicle in a
circular orbit isz 1/2
()
goReVc=r
● ☛☛ ● ● ’s6 ● O* ● *●’.●
●:;3f5::m~;
e● 0 *:. ● 00 ●:* :06● m
(67)
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● D ● ** ● 0* ●:* 9*O ● *
609 ● **● *** ● 000
● e :0 ● O● : ● ● 9● ●:0: “*:O●*-● a
where
R = the distance from the center of
the vehicle (considered to be a
go = 32.17 ft/sec2
the earth to
mass point)
Re = radius of the earth = 2.0908 X 107 ft
The equation for the velocity of a vehicle in an elliptic
orbit is15
(V2 22- 1= 2goRe ~RI + R2)
(68)
where
‘1 = the radius of orbit 1
‘2 = the radius of orbit 2
The total AV required to go from orbitl to orbit 2,
obtained by combining Eqs. 65 through 68, is
[[AV = Vcl X
-1/2 ~ _ 21/2(1 - x) (1 + x)1}
-1/2 _l (69)
where
final orbit radiusx=initial orbit radius
The burnout weight in orbit 2 can be obtained from a
knowledge of the vehicle weight in orbit 1, the AV required
for the transfer, and the vehicle vacuum I The equationSp”
relating these quantities is
● ☛ ● 9* ● *D ‘a ● m, ●● 9**
● e● **: : 57: : :.:● **
● b ●** ●*9..*.:..*
. be- -0- 6 -9- ● 00 ● 9
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
●☛✚● ☛● O● 0
● *
AV =‘Olsp) vac
in R
.—. -.38* 490
c: :● :●0: ● 00
..—. _. —● *V ● 8
9*●
::*
●:0 ●
(70)
where
R= weight in orbit 2
weight in orbit 1
From a knowledge of the burnout weight in orbit 2 and the
various component weights of the vehicle - tank weight,
reactor weight, etc. - the payload in orbit 2 can be
obtained. The results of this analysis are given in
Table 4. The weight breakdown for flying flight 3 into
a 300-mi orbit is given in Table 5.
In the Hohmann transfer part of the analysis it was
assumed that the circular orbits were coplanar and that
there were no gravitational losses.
VI. Ballistic Ascent
This trajectory was obtained from the previous work
given in sections III and IV. The vehicle was flown
straight up for a period of 16 see, at which time it was
kicked over to 13kand then flown to a specified height
(hCo). Upon reaching h= o The thrust was turned off.0 . .
and the vehicle allowed to coast to summit, dh/dt - 0,
at which time the thrust was cut back in and the vehicle
powered into a 300-mi orbit.
given in section IV were used
the flight from summit to the
The optimization equations
to calculate the portion of
300-mi orbit.
● 990 m ● *8 b*9 9*
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
——
——
.—●
e●
:o●
**●
**●
-9●
*●
●●
*●
*99e**9
●O
*●
*9*●
e●
:**●
9●
8**●
●:0
:00●*
zm.yo0ma.
mo0CD
m“
No0da-
‘No0U!
*-m00mm“
msNw-
m000.‘m+vsbA-
l-l
000N“
m1+wb00mI-4
N
00mm-
00N.
m1+00mti-m00Ino-*000
.mv00wv“v00cou
i-W000m-
G:CD
‘N-
!-+
z0N-
ab0Cu
0b&’
00m*-1+00m-
c-nN00mm
“w00020-
Ln
00‘N-
m1000F-.
t%z.+(s”In0z.m,-(
00Ino--00w.
$%00l-l
N-
r-00Nw-
b00mo-Co
00Noi-
Co
00:000@i-
GInInm.
wl-l
0zm“
1+m00t+00InmCD
00mN-100-$~
-
00N.3’
00r-l
m00In‘m00co.m000*-000m-
bv:.
N000cd’
:m0*1+Nr-
00my-0m+00mm00mw-
00mLc-
00mu-”
zmln-
000@i-
bd:N-
000m-
0coco00mNm
00,+7’
0a
0)r-lI00N
00v.
Nl-+
!-(I
00NF-
001+.Nr+00-$w-
d00W
00wm00UY
00m*-00m0-
=r
000.
w00In.
Inw
!-i
00m-
m
000N-
t-1+CY
m000G
.x-
0000-
00
wN
mGd
mIn
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ 90: ●:O ● 9* ● ** ● O● * ●
● **** ●: :0● 9
:: :: :0● O ●*: ● ** ● 9:* ●
TABLE 5
Weight Breakdown for Flight No. 3
H2 load
H2 tank
Structure
Turbopump
Nozzle
Reactor and pressure shell
Payload
Launch weight
Tank diameter
Ratio of over-all length to
diameter
Flow rate
Reactor power
lsp)vac
Dry weight
308,000 lb
24,000 lb
4,000 lb
9,000 lb
3,000 lb
22,000 lb
43,000 lb
413,000 lb
25 ft
6
800 lb/see
12,630 hfW
807 sec
62,000 lb
!!mm!m
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ● ✎ ✎ ● *9 ● *9 ● ** .*● ● *9 ● o
8 :*.*99*9● 99* ● 9● : ● 0
● ●:* : ●:0 :*. ● e
To determine the most efficient ballistic trajectory
from the standpoint of largest payload in the 300-mi orbit,
curves of total vehicle weight in orbit as a function of
131{were obtained with hc o as a parameter. From these. .
curves a value for maximum total vehicle weight was
determined for a given hc o and a curve of total vehicle. .
weight (maximum) as a function of hc o was obtained. The. .
results are given in Fig. 12. The vehicle launch weight
for this problem was 413,000 lb and the reactor exit gas
temperature used was 2170”C. These are the same values
used for flight No. 3 of Table 4. A comparison of the
payload for the ballistic aScent (41,000 lb) with that of
the elliptic ascent (43,000 lb) shows that, for a 300-mi
circular orbit, the elliptic ascent is slightly superior
to the ballistic ascent.
VII. Conclusions—
The trajectory calculations demonstrate quite clearly
that, for orbits above 100 mi, the ballistic and elliptic
ascents are far superior to the PAW ascent and that the
elliptic ascent is superior to the ballistic ascent. In
the elliptic and ballistic ascent calculations it was
assumed that the thrust could be turned off and on during
flight. This demonstrates the gains to be made by the use
of a nuclear rocket motor which can be recycled.
● 9 8*9 ● ** ● ● *O ●be● * : ; 64 : :.”● ***be
.0 ..: ●:. ..: . . . . .9
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ● *O ● 9* ● ** ..* ● .● * ● ,● Ce: : ●: ●● O** :● - : :*
● * ●0: ●:0 9 ●:0 ●
10.2I I I
)
ASSOCIATEDPAYLOADWEIGHT=41,000LBS.-
10.0—
9.8—
*‘Qx 9.6—m-1
l--sg 9.4—
2
<& 9.2—1-
9.0–
8,8—
8,6 I I I I20 3.0 4.0 5.0 6.0 7.0 8.0 9.0
THRUST-OFF HEIGHT, FTx 10-5
Fig. 12 Total weight in pounds, placed in a 300-mi orbitas a function of thrustoff height in feet for avehicle exit gas temperature of 2170”C, and alaunch weight of 413,000 lb (results for acomposite trajectory consisting of a gravity-turnpart, ballistic trajectory to apogee, and thenalong an optimum path into a 300-mi orbit; resultsshown here are for an optimum value of ~k)
● 9* ● ● ** ● ** ● *99* ●●
● :;62: :.:!● ● *
●8 ●90● 99●O*:0.●*
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
—— --● ☛ ● O* ● 9* ● O*
● ● ●● :***
● 99● :● ●:0: ●:0
Another way of pointing
has on a given mission is in
power density requirement at
——.—-● ☛☛ ✎☛● ● ☛● ☛☛☛● ● ☛● ● ☛80e ● 9
out the effect the trajectory
terms of power density. The
1900”C (see Fig. 9) for a
300-mi circular orbit mission drops from 0.452 Mw/lb to
0.208 Mw/lb in going from a PAW ascent to an elliptic
ascent. The sensitivity of payload in orbit to temperature
is also reduced when a vehicle is flown along an elliptic
ascent trajectory into a low earth orbit (300 mi).
In section V it was shown that a single-stage vehicle
having a launch weight of 413,000 lb and operating at a
temperature of 2170°C could place 43,000 lb of payload
into a 300-mi orbit. The three-stage Saturn-Titan-Centaur
vehicle, having a launch weight of 1,075,000 lb,16 will
place 25,000 lb into a 300-mi orbit. Replacing the Titan
with a LOX-Hydrogen system will increase the payload to
approximately 30,000 lb. The dry weight of the nuclear
vehicle is 62,000 lb as compared to approximately 90,000 lb
for the Saturn-Titan-Centaur vehicle.
A nuclear system having a launch weight of 72,000 lb,
reactor power of 2214 Mw, and operating at an exit gas
temperature of 2170°C (close to present day technology)
will place 3500 lb of payload into a 300-mi orbit. Tank
staging, see section V, will increase the payload to
4900 lb. The Atlas-Centaur plus a small solid-propellant
●0 ●00●00 ● ●*9● ● ● ● ●**::●00: ~ 63: : ‘.
● **● . ●m. ●.. ● . . .:. . .
●
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ✎ ● ☛☛ ● ☛☛ ..e ● . . .*● ● e
::. : : .: ● ●● * ●● b : : :0.. ●.:.:. . ●*. ●
third stage will place approximately 7400 lb of payload
into a 300-mi orbit.
chemical systems are
Caution must be
The dry weights of the nuclear and
approximately the same.
employed in drawing conclusions from
the performances of the nuclear and chemical vehicles
described above. The reason is that the performance of
the chemical vehicle is based on multiple staging, whereas
all the data presented for the nuclear systems are based
on a single stage. An example of this point is that by
going to a two-stage nuclear vehicle with a launch weight
of 413,000 lb the payload can be increased from 43,000 lb
to better
two-stage
The gains
against a
From
than 70,000 lb. Circular orbit missions for
nuclear systems will be given in a later report.
to be made in staging must also be weighed
decrease in over-all reliability.
the above performance data, but realizing the
implications of comparing a three-stage chemical rocket
with a singl.e-stage nuclear rocket, one concludes that
nuclear systems are superior to their chemical counterpart
(same dry weight) for missions which require large payloads
in orbit. ‘i!hereverse is true for Atlas-Centaur type
missions (small payloads) . The reason for this is that the
reactor weight
lowering power
does not decrease substantially with
requirements; thus the power density
● 9 ● 0
● * ●:9 ● 00 ●:* :** 90
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ● ✎ ✎ ● ☛☛ ● *9 ● ma ● *● ● 0808
● : ● 0 ● **a● * :0 ● O● : ● ● ● *
● ●:0 ● .:* ● ** ● 9
decreases, which in turn causes the percentage of dry
weight which can go into payload to decrease. I?uture
technology could very well lead to lower reactor weights,
lower tank weights, and exit gas temperatures greater than
2170°C, thus leading to the increased performance of
small-launch-weight nuclear systems. Present day technology
points in this direction.
1.
2.
3.
4.
5.
6.
7.
8.
9.
REFERENCES
K. W. Ford, Internal memoranda.
W. Hohmann, Die Erreichbarkeit der Himmelskorper,
Druck und Verlag R. Oldenbourg, Munich and Berlin,
1925.
Los Alamos Scientific Laboratory
(Vol. II), March 20, 1958.
L. Turner, Internal memorandum.
Report LAMS-2217
R. L. Aamodt et al., Los Alamos Scientific Laboratory
Report LA-1870, March 1955, p. 53.
J. L. Hartman, Internal memorandum,
G. P. Sutton, Rocket Propulsion Elements, John Wiley
and Sons, Inc., New York, 1956.
G. A. Bliss, Calculus of Variations, University of
Chicago Press, Chicago, 1925, p. 202.
F. P. Durham and V. L. Zeigner, Internal memorandum.
●. .**● . . . ● a.● ● ● ● 9’9
:: ●: ; 65: : ●-.::.0 ..: . . . ..: ●:. . .
amm9**** ● O* .:
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
9. ●om.*.●*m... ..9* ● *s: ::: ●:..
● ee● m : :0
●* ●0: ●:0 ●● ●** ●
10. G. M. Grover and E. W. Salrni, Internal memorandum.
11. H. Filip and A. A. Gonzalez, Internal document.
12. H. Filip and A. A. Gonzalez, Internal document.
13, C. E. Landahl, Internal document.
14. K. A. Ehricke, Astronaut. Acts, 4 VOIO 11, 175, 19560—
15. L. Page, Introduction to Theoretical Physics—-
(2nd cd.), D. Van Nostrand Company, New York, 1947
P. 95.
16. ABMA-DIR-TR-2-59, June 1959, p. 23.
9** ● ● ** ● ** 90●9* ●● : $y : : ::
● ●eee900 ● *
● * ● 6* ● ** ● ** :00 ● 0
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ☛ ● O* ● 80 ● *O ●ea●*● 9* cm ● *
8*:C ● 9**● :0 ● 9
● : ● *● ●:0 : ●:0 :9* ● 0
APPENDIX
FLOW DIAGRAM AND NUMERICAL METHOD
Input, box 1. Input numbers and identification are
entered into the machine on six cards as indicated. On
the first card any desired information (such as date,
name of problem, etc.) may be punched in columns 2 through
72 inclusive. On the other five cards, numbers are punched,
seven per card, in floating point form with ten columns
per number. Each number has the format +X.XXXXX+XX. The
decimal point is not punched but is assumed to be in the
position shown. The last two digits along with the sign
in the third last position are the power of 10 by which
the first six digits (with point as shown) are multiplied.
The nth number is punched in columns 10(n - 1) + 1 through
10n inclusive, with the sign of the number
10(n - 1) + 1 and the sign of the exponent
10(n - 1) + 8.
output . Output consists of a printed
in column
of 10 in column
listing as shown
in boxes 2, 4, and 13. Since the printer has only upper-
case letters and no superscripts or subscripts, the table
below is given to show the correspondence between the
printing on the listing and the symbols used in the report
and the flow diagram.
** ● 9* ● ** ● ● 00 ●●
:: : : 67e; ; :00● ***● * ●
● 0 ●’: ●:. ●0: ●:0 ● 0
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
Box 2:
BETAKD
CAPK
AO
BETAB
TC
FK
CNL
AEAT
Pc
FD
WFO
RHOT
RHOH2
RHOCH4
S?lifl
FNIBAR
FN2BAR
ABAR
CPH2
PD
CN
WL
● ✎ 9*9 ● a- ● *9 ● *e ● .40 ●: :
●●: :::
s●
● * : : : :*● * ●O: ● 9O ● ● ** s
In Report
Bk (printed
K
a.
E
Tc
k
CNL
Ae/At
Pc
‘D
WTF
PH2
‘CH4
a
LP
‘d
‘Nw.
L
in
mmlm●*● em ● ● ● ● 9
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
WR
FM1
FM2
Vz
TK
DELTI
ATCOEF
FM
THOFFH
THONH
H2F
HF
SETM4
Box 4:
WH2
WDOTH2
WTH2
WSH2
WTP
Wo
WCH4
WDOTCH
WTCH4
WSCH4
——. -~~i ●:a :00 ● 0. ● *O . .
●● a
● ● *● O
●0::●: :.. O
●4 m..●:0: 9*9 9** . .
WR
‘1
112
‘o
‘kAt
AT
Mav
hcoo.
hcon
‘2
‘fSETM4
● 9 ● ** 90. ● ● om .
:: :● * : & { :.:::.
● 0 ● *e ● *9 ●0:●:..*
m● ..● O* be
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
WN
WDOT
F
DT
T
v
BETAD
H
THETAD
TANACCEL
BETAPD
HP
THETAPD.L
THRUST
ISP
Box 13:
T
L
u
H
LAMI
LAM2
LAM3
W(T)
TH/W
v
. . .** ● *9 ● *O SO* U**● O* ●
: .: ●● mm:ea* .*● 0●oa*:@:o ‘..
. . m*m ● 00
F
‘t
t
v
~ (printed in degrees)
h
0 (printed in degrees)
i
6 (printed in degrees/see)
A
b (printed in degrees/see)
L
T
ISp
t
L
u
h
‘1
‘2
‘3
w(t)
T/W (t)
v
● O* ● .*b ● 8* 9*●e. ●u9* ● O* ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
ACCEL
THETAD
THETDD
BETAD
GAMMAD
Options.— -—
determined by
h., and SETM4.
~● m ● me ● O* ● ** ● *9 ● n
● ●● : ● 0
● O ● 0
● *● *.*
● ::0
●● *●:0 : ::
● ** ● .= ● e
ACCEL
e (printed in degrees)
6 (printed in degrees/see)
13(printed in degrees)
Y (printed in degrees)
The various ways of running the problem are
the five input parameters W;, hc 00, hc on,. ●
These variations center on when and how the&
thrust is turned off and on. The thrust is turned off
either by having the missile run out of fuel (determined
by W:) or by specifying a cut~ff height, hc o . It is. .
turned on again either at the cut-on height, hc on, or at..
the time when h = O, depending on the value of SETM4. If
SETM4 # O, the thrust is turned on when h Zhc on, and if.
SETM4 = O, the thrust is turned on when ~SO. The missile
goes under control of the variational part when it reaches
height h2, provided the thrust is on.
The tabulation shows various possibilities. Here “normal”
means that the quantity referred to is of a size which can
be expected; for example, “normal” for hc o would be a. .
value of h at which it is reasonable to turn off the
thrust, whereas “large” means larger than h can ever
attain. “Immaterial” means that the corresponding quantity
is never consulted.
● 0 ● *O ● 00 ● ● em ●
:: :● O i ?3-:::::0..
● 9 ● *. ● .* ● ** .:. ● *●
● ☛ ● ✌ ✎✍ ✎✎✛ ✍✎✛
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● 0 980 ● ee 8** 909 am● 9 ● ● *●00:: .:00● ** ●
80 : :0. . .@: ●:O ● ●:- ●
hcoo.
large
large
hcoon
immaterial
immaterial
normal large
normal normal
‘2 SETM4 Remarks
large immaterial Missile runs out offuel and finallyhits ground.
normal immaterial Missile goes up andinto variationalpart when h2h2 withthrust on all thetime.
large # O
normal #o
normal immaterial normal O
normal normal large # O
normal immaterial large o
9 ● b* ● ● ae ● *9 ● e
Thrust is turnedoff when h2hc o ,
. .and missile finallyhits ground.
Thrust is turned offwhen h211co , is
. .turned back on whenIp]-, and missilecon’goes into variationalpart when h2h2.
Thrust is turned offwhen h2hc o , is
. .~urned back on whenh = O, and missilegoes into variationalpart when h2h2.
Thrust is turned offwhen h2hc ~+, iS turned
back on when h2bc,011 ,
and missile eventuallyruns out of fuel andfinally hits ground.
Thrust is turned offwhen h2h
Co.’ is
turned back on whenh = O, and missileeventually runs out offuel and finally hitsground.
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
aiilbMp● 0 ● O* 9** ● O* ● ea ● 9
● *... . .● 90 * ie:;:0.● :●
● :●:0 : ::● *. ● . . ● *
BOX 1 1 Box 2
Red Ir+@
1* aati Ide@flncatlon
20d cad: .Sk K .OFTOk Cn
3rd card, Ae/At Pc ~ W; P= PH2
%H4
4th Cm’& *~i2xcPpdcU
6* card:‘L ‘R ‘1 ‘2 ‘o\a
61b cad: AT M h.“ % .0. ..0. ~z ‘f
SETM4
10, 3
m7)-1-+.“e’CNL’&ii2M
F=- a.“I”l + ‘2”2
i. Px21
c =—-
J’CH4
$-.000640 (K . 21
[1 - .)(++ K)
‘2
‘F-[1- F)W:
CH4 . ~; - ~~WF
H2 $(1 - F) W&T
‘T -%2
CH4 *KFW; P‘T =
PCR4
Prm&
Bill AndoraOn 7-4660 D3ck of Mix. 28, 1960
Ideolillcntkn ate, Name of Problem, eta.]
BETAKD-. CAETC- AO- BETAB. TC- FK-
CNL= AEAT= Pc= FD= WFo- RHm=
RROH2= RHOCH4= sm. FNIBAR- FN2BAR= ABAR-
CPRZ= PSI- CN= WL= WI@ FMl-
FM2= ~= TK= DELT1= ATCOEF- FM-
TKOFFH= T-Hoi-a= H2F= HF= SETM4-
Note: Co = s2.1?
R = 2782
:[W= + WR +: 1.15 PT$(Ft + 1, . @
%1W. -
‘ - (:’~f~::::)k+-o)
~T-8wT
P FCN C* w;
‘N - ~2.11 Pc
1/3
[
8(1 - F) w;D= -
. PM
1, “ -%+ ‘)
set idtti cordulom [or dlffarent!.1 uquatl.nm
V-v. h=O t=O
p-o 0.0
Set branch 1 to exit 1
Setbranch 2 co exit 1
Satbmch 3 t. exit 1
{
SO; branch 4 1. ●xit 1 U SETM4 = O2 U SETM4 - 0
● ☛ ● ☛☛ ● e. ● ● 909**..*.::0.:: . . . . .aiiiiii● *9*. ● ** ● *
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
,0 9*O ● 00 9*9 ● 9* ● 99* ● ● 0
●: ● .:. *::*● m : : : :9
● * ●*: ● em ● ● m* ●
From Box .S
Bax 4I
Prtnti
WH2- WDOTH2= wTH2-Fmm BOXCO18, 19, 20, 21,
wsH2- WTP= wo-
b
220 as, 24, 26
WCH4= WDO’TCff= WTCH4= wsaf4- WN= wDoT-
F- DT=Box 45
TV BETAD H THETAD TANACCEL BETAPD HP THETAPD L THRUST L9P tM“ - ‘old + ~
(Column headings)
I I 1. IBox 5
1
nhm dependent qummfes)
R = h + 2090s000 Note: go = 22.17
Pa= 14.7 e-~’z’oo Re - 2.0s08 x 107
[
P P1-. $U$S3
B= ePe
-2 U$>3e
v Bvo
P AP
~ - t - (length of time. thmt fn .~
,a. ~T, ~-h/WSOO
[
112o - .00414 h U h < 36OOO0-
975 U h a 35000
M-:
[
.37 u M=+ .9
CD - .6 + z.3fM - I) u .9< Ms 1.1
.3+$ if 1.1 < M
DSo ECD Pm d—.w (E found In BOX 3)
W. - W=tFB
ntegxat6 from t to t + &
ITO Box 6
UNCLASSIFIED
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
● ✍✎✛ .--wee m~~mu-
● . .● be:0 ● * ::
● : :●
:●:0 : ::●:0 ● .0 . .
FM. BOX 5
hBox 6
L = (% + 20908000)2 i
~=wT-~Tt
p:= 1:7 .-’J’:’”
Box ?S
No Han mic..ile Ye.-To Box 1
hlt gr.auld?
I
I
Lmm m thrust.
necad theat
which tbrut
is turned off.
S&Branch 3 to
E%lt 2.
T
BOX18 IExu 1
E%lt 2Exit 2
BOX 22 Box 23 I B- 24 I
n.. misa[le HIS Mckover n.. CUtou Jfls he fgllt H*, cut-m
Nllciltof *film teen height be.. No II* ken height be. f6i 507
fuel ? reached ? mmhed ? machnd ? reached ?
Yes -f.. No r,. NO Yes Yes t
& 19
‘rum off thmst, BOX 20 *
R-bad the at P=@k
which fArust .% Branch 2
1. furnsd off. to Exit 2
S& Branch 1 to
Exit 2.
1I
!
T. BOX 46
-
To 1
● 9 9** ● ** ● ● O* ●● *
::.w:● o ● ● * ● *O .:
‘m. . tbl’u6f.
Record time af
which thmst
1s tunwd on.
.%x Branch 4 to
Exit 3.
I
No
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
~-’- “~. . .** ● 00 ●8: ●:. ●*m.**:.* 9:*
.*9*
● *9
9 : :*● 0
fi~(ww~.. ●0: .e9 . ●:0 ●
From BOxcs 28, 27
BOX10
L-’,
U=o 1Valuea ti t - t,
h-hf
&y.9
kl - A;
1‘Ales at
\-+’ t-t,A3-<
{.175 IAll U Al = O
AA, -.0001 If Al-o
[
.175 lA~ If i,* O
‘% “ ~ool u &z-o
[
.176 IA31 if k, ● O
AAa -
0001 If A8-0
w Branch S to Iklt1.
+ ,Nm ‘ox,, 14, M, 16
.:0 ● D- ● *
●
‘w
Ist, >o? 1 Yes To Box 11
I No
E.31ectc. new set of ken:
a;-.005 A: - .0026 1: . -.00004
A; - .004 x; - .0026 A: --.00004
1: - .00s A; - .0025 i: - -.00004
A; = .002 h: - .@2z6 A; - -.00004
i: - .001 A; - .0025 A: .-.90004
wB0x24
law all sets , -entried?
No Yes
To BOX9
&Box 27
Prlti:
T [s negative.
JToBox 1
—
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
--- :.9 ●:0 ● . . ● ..! ● “
: ● . ●
***. . ●*::9*
: ● *
●●●:0 : :..
● O. ● . . ● .
WCmofm.=t-t, -l-o:i - RAL.I
. % 3L2
‘, =+- ‘d) 4’
J
u L wUM.
I II
I Exit 1
R-h-Re w go -32.17
R - 2.0908 * 101
““p, - ,:(’:,)]~ “
hla’rnb fromt = 0 tot -t,,
i . m,n
7.
~.l-fi+kqR’ R’ ‘
i.u
% 2%kl. T.—R’
j . -13
& .;~# - ,c&*
i -~R’
Flrd 10, ,mh Ume
‘(” “0 -‘% “ ‘B)T/w (q
v. J-
‘Ccu e m
t,=t +12
fl-*.*.m
‘1?--r2
Print 10, etch Uua
T-
L- IP H- IAM1- LAM7.- IAM3=
Wm. ‘1’IUW= V= ACCEG TNETAD= THKCDD-
BETAD- GAIUUD=
L
E-ax 14 ILO-L2-.
ho-h
A, -&;-AA,
Az - A:
%“’:
Set Br8mb5@ Ex!t 2.
T -/t
JToBox 10
L.~
“9s AA3 C3“‘“-‘f ‘h)Sc.Iw forh,. hi. d h3:
(o,jyj) =(c,) 1,1- 1,2.3
A&l -$014 - hl
}(MW - $1.W - hz
i@l = A&ldl - h,
To Wax8
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE
. . . . . . . . . . . . . . .-● ☛ ● ● ☛●✎☞☛ .:00 unumwt~ tuJ● * ● ●● OO :0 :00
● * ● 09 ● ** ● ● *9 ●
UNCLASSIFIED●*. ● ●00●*, ●*●** ● **9
● : :● *.* : :0::
● ● 999_?S+***.OQ.=OQ●oe~:...
APPROVED FOR PUBLIC RELEASE
APPROVED FOR PUBLIC RELEASE