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7/25/2019 FIGHTER DESIGN From Soviet Perspective
1/26
FIGHTER DESIGN
FROM THE
SOVIET
PERSPECTIVE
Richard D. Ward
General Dynamics Corporation
Fort Worth Division
Fort Worth Texas
.
AIAAIAHSIASEE Aircraft Design Systems
and Operations Conference
Seattle
WA July
31
August
2 1989
For permission to copy or republish, contact the American Institute of Aeronautics
and Astronautics, 370 L Enfant Promenade, S.W., Washington,
D.C.
20024
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Table of ontents
P GE
I Introduction 1
II Military Doctrine 2
A. Objectives
B Preparation
C. Modes
Ill
War F ighting Approach 5
A.
Readiness
B Sustainability
V. Weapons Requirements
8
A.
Effectivity
B Availability
C. Supportabilty
. Design Criteria 12
A.
Operability
B Reliability
C. Maintainability
D. Producibility
I. Design Approach 14
A. Design Constraints
1 Operational Constraints
2. Fabrication Constraints
B Heredity and Commonality
C.
Configuration Economy
1 Standardization
2 Modularization
3 Redundancy
VII. Com ments and Conc lusion
24
References .............................................. 2 4
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FIGHTER DESIGN FRO M THE
SOVIET PERSPECTIVE
Richard D. Ward, General Dynam ics Corporation
Fort Worth Division, Fort Worth, Texas
I INTRODUCTION
Close observation of Soviet aircraft at recent public
displays resurrected an old controversy in the West and
provoked important considerations: how can the Soviets
achieve Western levels of performance with apparently
less sophisticated machines? And if this be the case, why
not apply Soviet developmental criteria to the design of
Western aircraft?
Instead, a more important question is
why
are the
design criteria different? This question has been raised
because apparently Western engineers follow weapons
design constraints quite different from those imposed on
Soviet engineers. If, when examining Soviet military sys-
tems, Western perceptions are adjusted to consider the
Soviet approach to fighting a war, then much of what is
difficult to understand about Soviet design practices be-
come clear.
Bas ed on in-depth studies of m ilitary sciences and
history, Soviet military planners have deduced that while
the next war may be prolonged, battles will be short, in-
tense, calling for a massive flow of replacements. The
classic Soviet war-fighting concepts are surprise, concen-
tration, and thrusts into the operational depth. In this
context, weapons must be reliable, but only for the short-
term, with minimum support requirements. It is also im-
portant that w eapons be continually available in great
numbers.
Recent conflicts have shown that aircraft, on the
average, can only survive for a short time, and therefore,
there is little point to designing-in an operational life of
several thousands of hours. Accordingly, Soviet planners
require very high numbers of weapons and correspond-
ingly high rates of production. To the Soviet planners, this
means that simple, low-cost, reliable weapon systems
must be designed to ensure that great numbers can be
quickly produced.
To assure that large numbers of dependable, war-
ready weapons are available at the outset of a conflict,
operational weapons, in peacetime, are periodically re-
placed from war reserves stockpiles with new or refur-
bished counterparts, and the replaced weapons are in
turn sent to overhaul factories.
The equipment sent to
overhaul is actually being returned to the factories near
the peak of reliability so that, at the beginning of a war, all
operational weapons will be available for a specified, reli-
able comba t life. Com bat-life requiremen ts, therefore, de-
termine the design life and system redundancy of all criti-
cal components.
In meeting operational demands, Soviet engineers
design around relatively few, but highly standardized,
components produced in a manpower-intensive, but rela-
tively low-technology manufa cturing atmosph ere. To ex-
pedite production, outside components suppliers are con-
strained. To ensure minimum production disruptions, use
of advanced materials are conservatively incorporated,
and fabrication is done by semiskilled workers using rela-
tively unsophisticated machines and processes.
Soviet designers have evolved unique methods to
increase the producibility of weapons systems such as
minimizing the number of components, and by calling for
unso phistica ted fabrication techniques using standard-
ized tooling. Coincidentally, the w eapons that are simply
produced are also co nducive to short-term operational re-
liability and minimal supportability.
The purpose of this paper is to trace the Soviet
weapon s development levels necessary to meet their cri-
teria. Startin g with a compreh ensive national military
doctrine, the developmental hierarchy is followed through
the Soviet approach to fighting wars; next comes the de-
termination of the subsequent weapons requirements,
then the definition of the design criteria that meets the
weapons requirements; and lastly, the approach used by
Soviet designers to produce weapons compatible with the
military doct rine Figure I .
I N T R O D U C T I O N I
J AVAlLABlLlTY
SUPPORTABILITY
L
OMMENTS AND CONCLUSION
Figure 1.1 Soviet military doctrine determines and inte-
grates the Soviet Unions response to; the military aspects
of international affairs the contribution of the economy to
defense and the structure of the armed forces.
Richard Ward leads the Comparative Systems Analysis
Group at General Dynamics. He received his B.S.A.E.
from The University o Oklahoma in 1962. His engineer-
ing experience includes assignments on the
XB-70A X-
15 F-4 F- 15 F- 18 and several advanced design projects.
Copyright
1989
by General
Dynamlcs
orporation
hU rights reserved
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II. MILITARY DOCTRINE
Mil i tary Doctrine -
is a system of views,
adopted in a given state for a specfic time,
( A ) on the objectives and character of a
potential future war,
(B)
on the preparation of the country and its
armed forces for such a war,
C )
and on the modes of its conduct.
MarshalA. A. Grechko
The Soviet Union has been invaded and occupied
several times in its history. Soviet losses in World war II
both military and civilian, approached
20
million people.
Because of its history of wars, and especially that of World
War II, the leadership resolved that the only viable ap-
proach to prevailing in future large scale conflicts lies in
the security of a highly prepared standing army and a
comprehensive national strategy.
In preparing a foundation for the organization of
such an armed force, Soviet planners meticulously stud-
ied the history and nature of warfare and defined several
universal laws governing war and armed conflict.
These
laws address such criteria as the importance of political
and moral goals, relative economics and technologies of
warring nations, and the correlation of military forces.
To
conform to these laws, Soviet planners have established
a comprehensive and dynamic national military doctrine
to ensure national security and the projection of the inter-
national policies of the Soviet Government.
Under this
doctrine, Soviet planners rank resource allocations during
peacetime, so that under emergency conditions, combat
and reserve forces receive the highest support levels, and
non-essential peacetime functions are curtailed (Figure
2.1).
Figure
2 1
Soviet military doctrine is the systems ana lysis
approach to determining the optimum balance between
defense and non defense resources allocation
(A.)
On the OBJECTIVES and character of a potential
future war
Soviet military doctrine is formulated around the re-
quirement for the extraordinary preparedness of the
armed forces for war, including an integrated govemmen-
tal structure to support the necessary preparations. It is,
therefore, extremely important that the threat for which to
be prepared be well-defined. Their study of past wars,
and the resultant postulation of the nature of future wars.
have disclosed that certain general characteristics can be
expected:
Enemy surprise
attacks
are probable.
Enemy forces will have highly destructive weapons.
A war between modem armies will lead to
massive losses.
Immediately following World War II.Soviet military
planners conduded that the next war would be global in
scope involving intense nuclear exchanges with great
losses. Therefore. the Soviets developed a strategy call-
ing for extensive nudear forces, with a corresponding
deemphasis in conventional forces. In the 1960's. how-
ever, because of the growing acknowledgement of the
unacceptable destructiveness of this type of war, the mili-
tary doctrine based on global nuclear war was reevalu-
ated. Instead. Soviet leaders considered the viability of
large scale, conventional wars being fought without re-
sorting to the nudear option.
As
a result of a positive
evaluation. Soviet military doctrine underwent a radical
change. From the outset, however, it became apparent
that the enemy's nudear option must
be
eliminated, man-
dating an extremely high state of peacetime military
readiness to provide swift pinpoint destruction of the en-
emy's nudear arsenal. The foundation of this new strat-
egy was to be a standing-start strike capability to ensure
the enemy's nudear weapons destruction a difficult, if
not impossible,
task
- f the former Soviet strategy of mas-
sive operations
nd
ronts was used.
The new conventional war approach is very differ-
ent from the World War IIwafighting philosophy, which in-
volved massive armies needing extensive and vulnerable
mobilization before employment. The new approach calls
for smaller. but more flexible, armies capable of rapid and
unannounced employment.
This change resulted be-
cause the smaller, more flexible army can quickly drive
into enemy formations, denying them
a
viable nuclear de-
fensive choice (Fgure 2.2). The early destruction of the
enemy's nuclear arsenal is sti ll paramount, but if well-de-
fined targets are denied to the enemy, the Soviet armed
forces will have more time to destroy the weapons. Since
subscribing to this new war-fighting approach, the Soviets
have been reorienting national and international policies.
reorganizing military formations and redesigning military
equipment to ensure the viability of this new. more pro-
longed, conventional war-fighting approach.
B.) 'On the
PREPARATKM
of the country and its
armed forces for such a war
To understand the Soviet Union's military doctrine,
a brief explanation of its governmental system is neces-
sary. According to the Soviet constitution, the government
is divided into three main branches: the Supreme Soviet.
the constituent assembly; the Council of Ministers, admin-
istrator of the governmental functions; and the Communist
Party of the Soviet Union (CPSU), director of national
policy. In military affairs, the Party controls the Ministry of
7/25/2019 FIGHTER DESIGN From Soviet Perspective
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,. CO XU l
f p r n n o o p r u 0 . ,C ,bcn - flonawewe s r o p o ~
mpo o p r e l i c r o r xopnycz
dsarma
io vsvi
.I
I ~ ~ H T R ~ P ~
Blue Forces
*a 1.5
ca* l n6pn
Figure 2 2 Offensive operations in the enem y s opera-
tional depth during the Bundesw eahr s
1981
Strake Wehr
Exercise.
Defense through the Main Poli t ical Administration and the
De fense Indus t r i es t h rough the De fense Indus t r y
Depar tment o f the Cent ra l Commi t tee o f the CPSU
(Figure 2.3 .
COMMUNIST P A RTY
MILITARY FORCES
C O M M I T T E E
Figure
2 3
At the pinnacle of Soviet power structure is the
Comm unist Party, followed by the M inistry of Defense and
then the Defense Industries. Even though the Ministry of
Defense is a me mber of the Council of Ministers it holds
much more influence than the other members
As outl ined by the Soviet communist doctrine, the
Party-commissioned government administers the econ-
omy of the nation through a highly central ized planning
system. This system, additionally, ensures the integration
of industry, resources, and manpower necessary to fulf i l l
the mil i tary doctrine. Within the context of this system,
planners tai lored the mil i tary doctrine to the particular
Soviet experiences, envi ronment, and goals. In other
words, national mil i tary pol icies are priori t ized to reflect
Soviet capabilities. Although their economic system now
appears to be in the process of radical change, the parts
of the system necessary to fulfil l the military doctrine are
still in place and will continue to focus on a strong peace-
time m ilitary posture.
Soviet planners have developed a military doctrine
that takes maximum advantage of their strengths and
minimizes their weaknesses.
(C.)
And on the
MO ES
of its conduct.
Section
V
of the Constitution of the U .S.S.R.
V.
DEFENSE OF THE SOCI LIST
MOTHERL ND
Article 31.
Defense of the Socialist
Mothe rland is one of the m ost important
function s of the state, and is the concern of
the whole people. In order to defend the
gains of socialism, the peaceful labor of the
Soviet people, and the sovereignty and
territorial integrity of the state, the U SSR
maintains arme d forces and has instituted
universal military service.
The duty of the Armed Forces of the USSR to
the peop le is to provide RELIABLE DE FENSE
of the Socialist Motherland and to be in
CONSTA NT COMBAT READINESS,
guaranteeing that any aggressor is
INSTANTLY REPULSED.
As dictated bv its constitution. the focus of Soviet
rnilitary doctrine must be the maintenance of a high state
of mili tary preparedness. However, even the strongest
nation cannot afford to maintain al l i ts armed forces con-
tinuously at ful l readiness. A reasonable alternative for
the Soviets has been to keep adequate, f i rs t-echelon
forces in a high-readiness state so that at the beginning of
a
war they can comp lete initial strategic objectives. After
the confl ict is under way, second-echelon troops, in turn
reinforced by mobil ized reserves, wil l be quickly brought
to full strength. The reinfo rced secon d-ech elon troops will
be used, as needed, to augment or replace the first-eche-
Ion forces. With this sequence of force al location, the
armed forces can meet init ial strategic requirements be-
fore the enemy can be fully mobilized, and then complete
the ove ral l mil i tary goals, reinforced with second-echelon
forces.
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The foundation of the Soviet multi-echeloned strat-
egy is that first-echelon forces be especially equipped
and trained so they can be maintained in a high state of
readiness
The first echelon is supported by totally com-
patible second-echelon forces capable of being brought
quickly to full strength to
sustain
the inertia achieved by
the first echelon.
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I ll . WAR FIGHTING APPRO ACH
A. READINESS -
Combat Forces should
@
be self sufficient; manned and equipped to
perform defined m issions on immediate
notice for specific periods of time.
I \
B.
SUSTAINABILITY
-
Sufficient forces,
weapons, military equipment, rear
installations, and control systems in
operational units and rese rves should be
available to support initial war-fighting
stages and c ontinue adequate support until
industry can be fully mobilized.
The current Soviet warfighting approach is the re-
sult of a realistic assessment of m odern warfare:
Wide spread nuclear conflict is not acceptable.
Massive standing armies are no longer
operationally or economically practical.
Advanced technologies have introduced greatly
increased firepower and risks.
Throughout the Soviet post-war reevaluations of
the conduct of future wars, their war-fighting approach has
always incorporated two over-riding operational factors
readiness and ~~stainabi l i ty .hese factors are the princi-
pal ingredients of the classic Soviet operational concepts
of surprise, concentration, and expeditious thrusts into the
operational depth.
In Soviet terms, readiness is determined by suffi-
ciency of ground and air forces maintained in a state of
high preparedness, capable of seizing the initiative in any
confl ict. Su sta ina bil i ty is determined by the suffic iency
of material and troop reserves to support the army until
the conclusion of a prolonged conventional confl ict.
Weapons requirements are formulated to be compatible
with both imperatives.
A. READINESS
The Soviet leadership remembers well the enor-
mous losses fol lowing the German surprise attack in
World War
II
and are determined to never again leave the
U.S.S.R. vulnerable to this type of operation. They are
resolute in their commitment to maintaining the capability
to counte r or initiate surprise actions. This resolve has re-
sulted in the organization of select elements of the armed
forces into a very high state of readiness.
The p rincipal advantage of achieving surprise is in
the reduction of the e nemy s resistance; but to capitalize
on the ene my s temporary weakness, the surprise must
be exploited the attack sustained. Not only must the
first-echelon forces be trained an d equipped to begin op-
erations on extremely short notice, but second echelon
and reserve manpower and material must be quickly
made available to sustain the initiative through rapid
reinforcement, with troops activated after the battle
begins.
Surprise operations can greatly amplify war-fight-
ing effectiveness, whether in the attack or the counter-at-
tack. In prese nt term s, however, with the availability of
modern sophisticated detection capabilities, surprise op-
erations following a n y level of preparation are almost im-
possible. Therefore, within the current opera tional envi-
ronment, the only way large scale surprise operations can
possibly be achieved is by attacking (or counter-attacking)
w it h o u t mobilization. In other words, the likliest way for
an army to achieve tactical, operational, or even strategic
surprise, is to start military actions using only troops and
equipment already positioned in peacetime deployment,
without any redeployment or reinforcement standing
start readiness. Practically, large scale standing-start
operations will necessarily limit the size of available
forces, but the speed of advance and the subsequent
seizing of the initiative should ensure that military goals
will be achieved.
The problem for any military planner using stand-
ing-start operations, however, is determination of the
smallest peacetime first echelon size, as well as sustain-
ing manpower and material reserves that can be practi-
cally maintained and still be effective enough to first
achieve, then retain, the initiative. In view of the current
shrinkage of the Soviet military forces, this size determi-
nation becomes critical to the establishing first-echelon
readiness levels, as well as weapons operational and
technological requirements. The Soviets have chosen:
To dedicate select combined-armed forces to full
standing-start readiness.
To maintain the bulk of its armed forces on a
skeleton cadre status, which would take some time
to mobilize.
To maintain vast reserves of military equipment and
ammunition with which to equip mobilized
reserves.
B. SUSTAINABIL ITY
With the return of the emphasis on conventional
warfare, sustainability g ains added importance. Current
Soviet peacetime sustainability preparations are the re-
sult of thorough planning, with postulated wartime opera-
tions defining reserves in terms of a specified quantity of
reserve troops and stockpiled weaponry needed in pro-
longed conflicts. Reserve troops mu st be able to be mob i-
lized with minimum preparation to sustain the initiative
seized by the first-echelon troops. This readiness for
mobilization is perpetuated by reserve mobilization-type
training and a very important element of reserve units pre-
paredness being in the design a nd operating simplicity of
the equipment. Soviet military planners have, theref ore,
determined that equipment must be highly reliable at the
outset, but simple enough to be operated by newly acti-
vated reserves with minimal refresher training.
Massive material reserves are essential in the
early period of a conflict until the national economy can
be converted to wartime status. Once on a wartime basis,
materials that have been expended in battle or destroyed
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by hostile action can be replaced by the defense industry.
For instance, it is estimated that a significant percentage
of weapons produced, such as attack aircraft, are even-
tually stored as material reserves. In this context, Soviet
military equipment must be:
Designed to be operated with the minimum of
retraining of reservist familiar only with much earlier
versions.
Designed simple enough to be operated effectively
in the combat environment.
Designed for long-term storage
Designed to be produced in a wartime economy.
Under the past Soviet conventional war philoso-
phy, numerous material stockpiles were prepositioned
near the areas of potential operational employment of
Soviet or client state combat units. These stockpiles in-
cluded weapons, weapons and troop support equipment,
munitions, spares, tactical pipelines, mobile bridges, and
special equipment. Under the new conventional
warfighting approach, employment of the past practice of
widespread prepositioning of war materials reserves cre-
ates several operational problems:
The primary delivery method of the MMR, from the
strategic level stockpiles to the operational level com-
mands, will be by heavy and medium-lift fixed-wing as-
sault transports Figure 3.1). MMR delivery from the op-
erational level commands to frontal tactical) units will be
by medium and light-assault fixed-wing transports, and
heavy and medium-lift helicopters Figure 3.2, 3.3) . To
meet the MMR concept, stockpiled items must be de-
signed and packaged to meet airlift constraints. For in-
stance, items such as portable roadways, field pipe, and
mobile bridging will have to be reconfigured to incorpo-
rate structural plastics and graphite composites to reduce
weight.
Drawing materials from widespread stockpiles to
support the accelerated operations of the new,
smaller, flexible and greater firepower combined
arms units presents difficult problems in transport,
vulnerability, and timeliness.
Modern h~gh-techweapons demand frequent
~nspectlon, nd the subsequent complex
maintenance cycle needed to sustam stockp~les f
th~s
quipment,
11w~dely eployed near potentla1
war zones, would ser~ously egrade read~ness
Maintaining numerous widespread and redundant
stockpiles of costly advanced technology
equipment is neither operationally nor
economically feasible..
To meet the sustainability requirements of the new
conventional war, Soviet planners are shifting from locat-
ing war reserves in numerous prepositioned stockpiles at
operational level locations to fewer stockpiles concen-
trated at strategic level locations. The repositioning of
these
mobile m teri l reserves
MMR) stockpiles aft,
to the strategic rear, better supports the new warfighting
approach by:
Permitting warfighting materials to be delivered
on paths normal to the front to better focus,
concentrate, and shorten support to rapid deep
penetration operations.
Positioning high-tech equipment stockpiles near
major repair and overhaul facilities for more
efficient maintenance.
Reducing redundant high-tech equipment in
reserve, by concentrating stockpiles.
Figure 3.1 The An-124 Ruslan heavy-lift assault transport
delivering cargo containers. Maximum payload is 150,000
kg 330,693 Ibs.)
Reducing the vulnerability of stockpiles by the better Figure 3.2 The Soviet Air Force Mil-24 Halo Heavy-lift
concealment and defense possible in the strategic Helicopter has a payload 20,000 kg 44,092 Ibs.)
rear.
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Figure
3 3
The An-
12
Cub medium-ift assault transport
has a payload of 20,000 kg. 44,092 Ibs.)
To achieve standing-start readiness and in-depth
sustainability, the Soviet military is developing moderately
sized, highly integrated, combined arms organizations
able to effect almost immediate transition from peacetime
to wartime operations. What appears to many Western
observers to be a conscript army built around second-rate
weapons, is actually a well-conceived and effective
fighting force equipped with highly support ble
weapons, v il ble quickly in great numbers.
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IV. WEAPONS REQUIREMENTS
A EFFECTIVITY
- The ab ility of people,
@
equipme nt, and facili ties to p erform required
missions.
B AVAILABILITY
The capac ity of troops,
IL
weapo ns, military equipment, rear install-
ations or comma nd and control systems to
preserve or quickly restore their com bat
capacity.
C SUPPORTABILITY -
The acquisition
@
of raw materials and people, their trans-
formation into war-fighting and war-
sustaining systems through their pe acetime
and wartime employment.
The Soviets recoanize that since wars will involve
large scale operations and losses, weapons must be both
effective and plentiful. In this context, operational require-
ments for availability must be integrated with supportabil-
ity and operability. To appreciate how the Soviets inte-
grate these requirements, an understanding of their ap-
proach to operational level war-fighting is necessary,
especially the initial stage of a conflict, during the transi-
tion from pea cetime to wartime posture. An example of
the character of the Soviet transition is found in a typical
frontal aviation regiment's operations in peacetime,
during the transition to war, and finally during wartime.
Peacetime Operations and Support
The foundation of the Soviet approach to readiness
resides in the peacetime ope rations and support (O S)
cycle of its military equipment. The Soviet O S cycle is
designed around the premise that, in peacetime, postu-
lated comba t life must be preserved. This preservation is
accomplished by requiring that weapons, such as aircraft,
are never used in peacetime beyond that point in which
the remaining reliable flight-hours would be inadequate
to meet what Soviet planners have projected to be the ex-
pected wartime combat life (Figure 4.1 . This philosophy
was developed in response to the earlier outlined readi-
ness requirements which state that at the beginning of a
war, all combat equipment must be available to the com-
mander for a specified and reliable combat life.
PE AC EW E POSTULATED MARGIN PROBABILITY
BURN TRAINING WARTIME OF OF
IN OPERATIONS COMBAT LIFE SAFETY FAILURE
L
RE DINESS CRITERI
UGHT HOURS Not To
Scale)
Figure 4 1 The com bat-life requirement determines the
design life and redundancy of all critical components and
therefore, the overhaul schedules.
Combat aircraft are replaced in the operational in-
ventory while the projected combat life remains, to ensure
that all remaining operational aircraft retain the projected
com bat life at the beginning of a conflict. This combat life
preservation requirement is met by a weapons support
cycle which ensures that when peacetime training hours
of the equipment have reached the point when only pro-
jected combat life remains, the aircraft are withdrawn from
service and sent to overhaul factories to be refurbished,
and in turn replaced with refurbished (or new) aircraft from
reserve stockpiles. The withdrawn aircraft that were for-
warded to overhaul factories to be refurbished are then
sent to the materials reserves stockpiles (Figure 4.2). In
this way, at ?he start of a war, o peratio nal units are
equipped with reliable aircraft, supported with abundant
supplies of relatively unused aircraft retained in large re-
serve stockpiles.
OPERATIONS CENTER
TRAINING
MAIN
O P E R A T I N G
LINE REPLACEABLE BASE
UNIT REPAIR
GROUND FLIGHT-
SUPPORT
. AIRCRAFT
SERVICING
.
FAULT ISOLATION
REMOVE AND
REPLACE
Pt CETIME
SUPPORT
CYCLE
D-LEVEL
W A R
R E S E R V E
STOCKPILES
. COMBAT LlFE RENEWAL .WARTIME RESUPPLY
OVERHAUL FACTORIES . SUPPORT CYCLE BUFFER
Figure 4 2 The Soviet Aviation 0 S cycle revolves
around the main operating base which contains one air
regiment of about
5
aircraft.
Also w ith this support cycle, m ost of the problems of
wartime maintenance and repair are also circumvented
because, in peacetime, operational aircraft are never al-
lowed to accumulate enough hours to have wear-out-type
failures during the postulated combat life. In other words,
war reserve stockpiles of crated aircraft are used to main-
tain equipment readiness during peacetime by ensuring
scheduled replacement of operational equipment with
new or refurbished equipment before major unscheduled
repairs are required. So at the start of a war, Soviet mili-
tary equipment will have few of the routine maintenance
problems inherent with equipment used in extensive
peacetime training.
Because Soviet weapons must be refurbished
while still reliable, the overhaul cycle must be quite fre-
quent, for example, the MiG-21 Fishbed is completely re-
furbished before
500
flight hours (the F-4, over
3000
hours). This low-ho ur overhaul frequency for Soviet fight-
ers have created a serious misconception in the West that
the equipment is assumed to have worn out in very short
order. In fact, hard-line removal schedules are base d not
on when a system wears out, but
~ r
he effective combat
life remaining in the system. This system is important be-
cause: 1) a high degree of wartime reliability is ensured;
2) airbase level repair frequency and troop training re-
7/25/2019 FIGHTER DESIGN From Soviet Perspective
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quirements are minimal; and 3) standing-start employ-
ment is practical. Consequ ently, comba t-life projections
are the single m ost important factor in the design life and
system redundancy of all critical weapons components.
In peacetime, to m aintain operational aircraft on a
main operating base (MO B), al l airbase level mainte-
nance and inspection are done from m obile repair shops -
Soviet acronym PA RM (Figure 4.3). These truck-mounted
shops are on call for both scheduled and unscheduled
maintena nce. If the repair is minor, the failed module is
repaired by the PAR M personnel at the MO B; if the repair
is major, or even m oderate, the module (or the whole air-
craft) is crated by the P AR M crew and sent to an off-site
intermediate-level repair depot. In this way, air bases can
be operated with only a few highly skilled personnel and
sophisticated repair facilities. Also, organizational level
(ground crew) activities are limited to simple sustaining
maintenance, inspection, and supervision of aircraft ser-
vicing. In summ ary, the sole responsibility of the airbase
LIGHT LINE DI GNOSTIC EQUIPMENT RR NGEMEN T
IEEE 488 TYPE BUS
C LIBR TION EQUIPMENT SCHEM TIC
ltEE 488
TYPE
BUS
Figure 4.3 Inspection and repair is conducted from mo-
bile repair shops
PARM.
and orga nizational level organizations are to ke ep opera-
tional aircraft continuously m aintained in a run-in state,
therefore keeping the squadrons approaching fu l l
strength and ready for wartime operations at a moment's
nnt on
Transition from Peacetime to Wartime Operations
and Support
All the maintenance procedures and equipment
employed on the peacetime airbase are optimized for
standing-start wartime deployment. As shown in the
peacetime O&S cycle, the Soviets have developed this
capability by employing mobile support organizations, or
PAR M units, with specialized weapons support equipment
to perform peacetime aircraft and airfield maintenance.
The reason for the total mobility of support facilities
is to assure that complete aviation regiments can be
transported quickly to austere dispersal sites. This de-
ployment option is practical due to the limited mainte-
nance responsibil i t ies on peacetime bases resulting in
smaller support units allowing complete tactical aviation
units, including flight line support, airbase level repair
shops, inspection and armaments vans, and flight opera-
tions control vans, and towed war-ready aircraft -- to
be convoyed to remote sites (Figure 4.4 . It is important to
note that towing aircraft eliminates expose d flight and ra-
dio traffic, normal during conventional dispersal opera-
tions i n which aircraft must be flown to remote sites.
Incidentally, Soviet fighters are designed to be towed with
specially designed tow bars at 2 kmlhour.
Figure
4.4
The nitial activities of a war are critical to at-
taining the initiative. If feasible the air regiment including
the aircraft will be deployed by convoy under the cover
of
darkness. If the conflict has started and therefore clan-
destine dispersal impossible the aircraft will be launched
on the first sortie and recovered at the dispersed base
with beacons
The transition from a peacetime to a wartime pos-
ture involves an important change in the O&S cycle
(Figure 4.5). The principal modification is that the over-
haul factory and repair depot activities are suspended be-
cause the Soviets believe that in the fog of war, these
operational O&S functions would only be a complicating
factor. Anyway, dama ged aircraft needing repairs above
the dispersed base maintenance support level, are usu-
ally nonrepairable - a situation unique to aircraft. Instead,
of repairing aircraft with major battle damage, replace-
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The effectiveness evaluation of each w eapon s contribu-
tion to the overall mission requires that a balance be
struck betw een cost, numbers, reliability, an d war-fighting
capability. Because the aircraft is considered to be only
one of the many assets assigned to the Soviet comman-
der, the task of aircraft and therefore, its design specifica-
tions are defined in the context of combined arms opera-
tions. Aircraft need only fulfill a complem enting role in the
commander s overall mission and not a role based on
maximum possible performance. The Soviets also be-
lieve that becau se of the fog of battle, weapo ns specifi-
cally aircraft should be optimized to only one mission to
minimize the systems complexity, simplify support, and
allow less e xtensive training.
In other words, single-mis-
sion criteria, in conjunction with limited performance re-
quirements, allow weapons to be very cost effectively de-
signed, if produced in sufficient numbers to overcome a
possible advantage of higher technology enemy equip-
ment.
In the Soviet v iew system sophist icat ion
should be determined primarily by the technical
qual i f icat ions of maintenance personnel func-
tioning in a wartime environment. Therefore, a re-
liable aircraft, easier to support and maintain, is more ef-
fective because it is more dispersible thus , survivable
and has a higher sortie rate over a longer time. This
wartime operational approach dictates certain peacetime
requirements:
Frequent scheduled inspections a nd over-haul.
Very simple design criteria.
Over design of all critical components.
B. AVAILABILITY
Readine ss is most visible in the Soviet rhethod for
ensuring troop and weapons (aircraft) availability for rapid
transition from a peacetime to a wartime posture.
In
peacetime, the availability of reliable aircraft for wartime
operations are ensured by the combat-life preservation
support cycle. Availability is also ensured by a large ma-
terial reserves, incorpo rated to sustain the peacetime
support cycle, because in wartime the same reserves will
be available to replace combat losses.
C
SU PPOR TA B IL ITY
Successful military operations call for a discreet
balance of combat operation and com bat support capabil-
ity. Neither function has reign over the other because
both are interdepen dent aspects of war-fighting. The de-
sign of weapons should, therefore, be influenced as much
by supportability and maintainability as by performance.
In the Soviet context, supportability requires simple and
fast maintenance and servicing with minimal support
equipment and crews. Performance must be compatible
with these requiremen ts. In fact, seve ral past Soviet
weapons prototypes have been rejected for production
because of supportability problems, although they were
superior in performance to competitive designs.
In response to the m il itary imperatives of readiness
an d sustainabi li ty , Soviet weapon requirements are
bas ed o n very sp ecialized interpretations of availabil ity,
supportabil i ty, an d effectivity. The criteria for Soviet
weapons design is to ensure that weapons are oper ble
within the context of the combined arms organizations,
reli ble enough for commanders to dep end on high
levels of availability, m int in ble in a realistic wartime
environment, and producible in great enough numbers
to preserve reliable combat life and replace wartime attri-
tion.
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V
DESIGN CRITERIA
A OPERABILITY - The design of weapons
to conform to the overall war-fighting
infrastructure.
B
RELIABILITY
The design of equip-
ment to perform required functions
depend ably for a postulated combat life.
C MAINTAINABILITY The combat
servicing and repair characteristics of
weapo ns necessary to minimize combat
requirements for test equipment, trained
personnel, and spares.
D PRODUClBlLlTY
-
The de sign of
equipme nt to b e more easily m anufactured
in both pea cetime and wartime environments.
As stated over and over aaain, the Soviet war-
fighting ipproach emphasizing readiness and sustain-
ability dictates that combat and support systems must be
available to the commander for a specified combat l i fe.
This combat-life requirement establishes the aircraft de-
sign criteria.
A OPERABILITY
Weapons operability, in the Soviet context, is the
measure of the balance between advance technology
and reliabil i ty. On one hand, there is the choice of
weapons that employ all the high-risk, advanced tech-
nologies available, which need complex support systems
and training; but if on the other hand the military planners
opt for older and familiar low-risk systems, the failure to
utilize advanced technologies will deny military forces in-
creased firepower. In the attempt to achieve the optimum
balance of technology application, Soviet military plan-
ners have ana lyzed opera t iona l e f fec t iveness by
methodically evaluating performance against readiness.
As a result, of this compromising approach, Soviet military
equipment appears to be markedly inferior when com-
pared to its Western coun terparts. In fact, one of the
pr inc ipal d i f ferences between Soviet and Western
weapons is that the Soviet weapons are designed ac-
cording to t he rigid combat readiness demands requiring
short-term high combat-life reliability and not maximum
performance with long-term, peacetime durability.
Criteria for designing weapons to operate in com-
bat must be d etermined by a realistic view of the wartime
environme nt. The Soviets believe that under the intensity
of combat the operator's ability to make anything but the
simplest maintenance decisions will be greatly hindered.
If ground crew members must function while under attack,
at night, in snow, and wearing chemical protection gear,
operating efficiency will be inherently minimal. Soviet
planners require that weapons must be designed to be
operated and maintained effectively in such situations.
The extent of the attention given wartime operability of
Soviet aircraft i s shown by the fact that many crew chiefs
for Soviet-built fighters in Third World air forces are un-
able to read, yet frequently maintain higher sortie rates
than companion Western-built aircraft needing educated
crews. Obviously, Soviet crew chiefs can read, but the
necessity to read such items as maintenance manuals
during the heat o f combat should be the exception.
To ensure that e ach new aircraft model is compat-
ible with the wartime operability requirement, the Ministry
of Aircraft Industry (MAP), in cooperation with the respon-
sible prototype design bureau (OKB), builds approxi-
mately 50 preproduction aircraft. These aircraft are sent
to a typical operating base for a protracted operational
test and evaluation (OT E) stage, where the airbase
crews operate and maintain the aircraft under the close
observation of MAP and OKB engineers. Following the
OT E stage, the aircraft, some airbase crews, and the
engineers, return to the factory and correct problems
ident ified during the test. The aircraft design is corre-
spondingly modified and then goe s into production.
B
RELIABILITY
Reliability, in Soviet terms, is the measure of in-
creased war-fighting availability and survivability while
decreasing support requirements. The Soviet goal is for
combat equipment that does not have a fabrication or
wear-out type failure for i ts postulated combat l i fe.
Reliability does not mean incorporating several levels of
redundancy or adding extensive self-test systems. The
Soviets design-in redundancy and self testing, but only to
a limited extent. They also employ the universal methods
to enhance reliability of quality assurance, failure history
analysis, selection control, and viability tests. The Soviet
reliabil i ty requirements, however, rely heavily on two
other methods: highly over-designed critical components
and extensive use of parts of established reliability.
By over-designing parts, many possible manufac-
turing faults resulting from low-skilled manpower (such as
during wartime) and high production rates are circum-
vented. For instance, if a panel is designed to be over-
strength then the rivet and spot weld patterns do not have
to be precise to be reliable.
By use of parts with proven reliability, such as ma-
ture components from older aircraft, the reliability has al-
ready been established. Additionally, repairs will be more
reliable because the maintenance crews are already
trained in the repair of the familiar component, using fa-
miliar repair equipment.
C MAINTAINABILITY
Equipment maintenance in wartime is a procedure
the Soviets believe should be avoided, not made easier.
Soviet weapon requirements are based on the premise
that any maintenance in the combat zone degrades effec-
tiveness because repairs call for additional and valuable
maintenance person nel, as well as stores of repair equip-
ment and spare parts. Also, to make the aircraft easily re-
pairable under combat conditions, costly on-board main-
tenance space must be allocated and num erous structural
degrading access doors incorporated. It must be recog-
nized, however that Soviet weapons are subject to un-
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scheduled m aintenance (as are all machines), but in their
case extensive efforts are made to eliminate, but only for
the postulated combat life, as much maintenance as pos-
sible.
production s assigned. Incidentally, operational aircraft
being returned for overhaul must be returned to the
factory where they were built to be compatible with the
tools and machines.
One of the Soviet s principal approaches to elimi-
nating wartime maintenance would probably be unac-
ceptable in the West, namely, scrapping combat aircraft
and m ajor components requiring more than a few hours to
repair. The Soviets believe that replacem ent from reserve
stockpiles is more effective because the time and person-
nel needed to effect repairs would only hinder austere
dep loyment opera t ions , mo b i l i ty , and sor t ie ra te .
Additionally, they believe most battle-damag ed aircraft
can only be effectively repaired at major repair depots
anyway, which, to the military commander, is the same
thing as losing the aircraft. It shou ld be noted that the out-
of-order aircraft will be eventually reclaimed by special
salvage units, but this will have little effect on the com-
mander s ability to accomplish his immediate m ission.
To meet the design criteria for each new weapons
system the
Soviet ainraff
designer is controlled by rigid
operational and fabrication design constraints. His
ptincipal
ppm ch
to meeting these wnstraints is by limit-
ing additions to new models of advanced technologies
and new components. This design conservatism is
sustained in the
f m
f design heredity and component
commonal ity. Developing weapons with adequate
performance which still meet the design constraints is
aoaomplishedby the mububous ancing of resources and
requirements or configuration economy.
The main drawback of abandoning weapons
needing repa irs during wa rtime is the requirement for a
large ma terial reserve and special training to reassemble
the replacements. But, in the Soviet peacetime support
cycle, using replacements from reserve stockpiles is part
of their approach to keeping combat equipment in stand-
ing-start readiness condition.
Therefore, the low level of
peacetime aircraft repairs on airbase is conducive to the
wartime requirement in which operational units should
have to make on ly l im i ted f ie ld ma in tenance .
Coincidentally, if weapons need not be readily field re-
pairable, many complex and costly design features can
be avoided, such as repairable parts and access panels.
To meet Soviet sustainabil i ty requirements, the
design of combat equipment must be compatible with
massive production runs, particularly undet wartime
conditions. This manda te dictates that the organization of
the national economy be compatible with defense pro-
duction. Accordingly, weapons design must be compati-
ble with the limitations and capabilities of a defense in-
dustry structured for wartime production. Th e designer
must balance cost against performance, advanced fabri-
cation processes against available machinery and man-
power skills, advanced technologies against production
quotas, materials against resources, and complex and
widespread manufacturing networks against concentrated
wartime production centers.
These considerations rely
heavily on simplicity of design.
To balance producibility and performance, Soviet
planners require that weapons nee d only be
adequate
to
meet a specific mission for a given combat life. This per-
formance adequacy or limit allows simpler and cheaper
fabrication materials and processes, which, in turn, facili-
tate massive production runs. One compromise to pro-
ducibil i ty, is that we apons must be producible in a
wartime environment by rejecting more effic ient and
economical, indu strial networks for concen trated industry
centers with less vulnerable transport infrastructure. H
ence, a larger percentage of each Soviet aircraft is
manufactured at each assem bly factory than in the West.
In this system, after successful prototypes are approved
for production, they must be redesigned to be compatible
with the avai lable processes of the plant where
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can be airborne in less than 300 meters, an important ca-
pability for operating from damage runways and remote
deployment sites.
b. Landing to Takeoff
Towing the Su-25 Frogfoot and the Su-27 Flanker
before and after flight operations is done by attaching a
towline from the heavy-duty towbar to the main landing
gear to pull the aircraft, and attaching a special steerable
fitting to the nose landing gear. In this way, the much
stronger main landing gear takes the towing loads while
the aircraft nose wheel is steered from the tow truck
Figure 6.2). For the MiG-23 Flogger and the MiG-29
Fulcrum, the towing system is designed so both towing
and steering is with the nose landing gear Figure 6.3).
An interesting note is that current MIG fighters are the
same width, ensuring the same tow and hanger width
Figure 6.4).
Figure 6.2 The Su-25 Frogfoot and the Su-27 Flanker
use special tow bars designed with main gear towing and
nose gear steering for cross country and rough field op-
erations.
Figure 6.3 The MiG-29 is towed y both pulling and
steering with the nose landing gear.
MiG 23 FLOGGER MiG 29 FULCRUM MiG 21 FISHBED
Figure 6.4 The width of the aircraft is dictated by towing
and shelter constraints. The MiG-29 Fulcrum with the
currently detachable outer wing panel removed is the
same width as its to predecessors the MiG-21 Fishbed
and the MiG-23 Flogger.
The logistics support of Soviet high-performance
combat aircraft during wartime calls for special design
considerations. As noted earlier, Soviets only allow very
minor repairs to be done by the aircraft ground crews with
almost all tasks limited to preflight and postflight activities.
This very limited organizational level approach to main-
tenance results in many significant design characteristics
of Soviet aircraft. This feature is feasible because with the
short-term, high-reliability systems required of Soviet
weapons, frequent repairs would not be needed, consis-
tent with the wartime environment. This maintenance
philosophy also permits the use of lower-skill level ground
crews. Generally, this wartime-oriented method of main-
taining aircraft ensures high peacetime readiness and ef-
ficient wartime sortie generation.
To test and warm up on-board systems before each
flight, Soviet fighters have power hookups on the left side
where electrical power line from the aircraft support truck
can be connected Figure 6.5).
The hydraulic, avionic
and fuel systems can be readied for flight with this
auxiliary power source and the only task required before
take off is to start the engine.
To not jeopardize the mission, several redundant
modes are available to the ground crew for wartime ser-
vicing reliability of the current generation aircraft. For in-
stance, refueling backup systems are required on all
combat aircraft. The primary method is by single-point
pressure refueling through NATO compatible receptacles;
the backup is with several gravity feed receptacles. For
aircraft that carry external tanks, the tank attachment fuel
ports using on-board fuel pumps are also available
Figure 6.6).
Wartime inspection and repairs are accomplished
by dispatching PARM units, as needed, from a regimental
repair center to the dispersed base. Inspection is simpli-
fied by designing the aircraft; so that, umbilicals for diag-
nostic data retrieval equipment can be quickly attached
without opening large access panels Figure 6.7). The
unprocessed data is down loaded to the truck-mounted
PARM shops for analysis. This approach reduces on-
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Figure
6.5
The external electrical power receptacles of all Soviet fighters are on the left forward quadrant of the
fuselage or the left forward wing root.
MiG 29 Fulcrum A
ngle Point Pressure
Figure 6.6 The single point refueling for the MiG 29 is lo
,, '
cated on the left side. The gravity feed refueling recepta
t
t
,a \
i
\
cles on the MiG 23 and Su 27 are located on top of the
i
'$,
fuselage and on each wing.
5
Su 27
Flanker
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board processors, access time, and eliminates equipment
bay exposure. An added advantage to this approach is
that the aircraft skin can be designed with fewer access
door discontinuities, allowing more efficient and therefore,
lighter-weight structure. Incidentally, this structural conti-
nuity permits very efficient composite applications.
Soviet aircraft attrition replacement during wartime
is accomplished by replacing the damaged aircraft, or
components, from reserves stockpiles. Therefore a large
percentage of all combat aircraft in the air force inventory
are in reserve storage. To facilitate this requirement,
Soviet frontal aviation aircraft are designed to be com-
pactly stored in a special crate and from which they can
be quickly removed and assembled. For instance, the
disassembled MiG-21 Fishbed is stored in a crate
approximately 47 feet long and 10 feet wide (Figure 6.8).
The MiG-23 Flogger crate had to be larger, about 67 feet
by 17 feet, to allow the longer fuselage, and wider for the
variable sweep wing carry-though structure. The MiG-23
replacement, the MiG-29, however, was a very different
configuration but was required to fit into the same volume
(Figure
6.9 .
To meet the MiG-23 Flogger size constraint,
each wing of the MiG-29 Fulcrum is designed to be disas-
sembled into two parts and the interchangeable, vertical
tails removable. It should also be noted that all the spares
necessary until the next overhaul are stored in the crate
with the aircraft.
Disassembly, of Soviet aircraft for storage, calls for
special structural design considerations, such as limiting
disassembly attachments to a few simple lugs, three for
the MiG-29 winglfuselage attachment (Figure 6.10). This
approach requires concentrating load paths at these few,
very high stress points. The Soviet design solution has
been to make the center fuselage box, which carries wing
and landing gear loads, out of steel, a nonstrategic metal
that is easy to weld and has high bearing strength.
Figure
6 7
Diagnostic umbilical connectors are concentrated on the right wall of the Su 27 Flanker nose wheel well.
Fabrication onstraints
are those design fea-
tures incorporated in the aircraft configuration compatible
with the resources, machines, and manpower available in
a wartime industry. Additionally, these constraints must
facilitate massive and high-rate production runs neces-
sary to meet peacetime material reserve requirements
and prolonged conflict attrition replacement requirements.
An example of fabrication optimization is in the design of
the horizontal stabilizer of the Mi-26 Halo, the world s
largest helicopter (Figure 6.11). The materials are steel
tube spar, plywood ribs, balsa wood leading edge, and
canvas skin therefore, the component is extremely easy to
build and therefore, very inexpensive. This method of
construction was chosen because of the part s location (it
receives frequent damage from flying debris), and with
this design, it could be simply and economically replaced.
Figure
6 8
The MiG-21 Fishbed is stored in
a
sealed shipping crate including
dollies, fixtures, tech manuals, and tools necessary for assembly. Anticipated
needed until the next overhaul are also included.
all the
spares
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Figure 6.9 To meet standardized storage requirements
the disassembled MiG-29 Fulcrum fits in the same volume
as its predecessor the MiG-23 Flogger. In fact the length
constraint on the Fulcrum caused the RD -33 engine after-
burner to be less than optimum length causing extensive
development problems.
Figure 6.1 1 The Mil Mi-26 Halo horizontal stabilizer is a
low-cost design easy to replace.
Cover for Win
Figure 6.10 To facilitate disassem bly for storage
wing/fuselage attachment loads are concentrated at no
more that three lug points. To carry these concentrated
loads the center fuselage structure of current MiG fighters
incorporates large w elded steel assemblies.
To ensure s implic i ty in product ion, minimum
assembly and finishing standards are used -- where not
critical. Exam ples of aircraft construction practices on the
MiG-29 show that:
Little emphasis is placed by Soviet designers on
tolerances in noncritical areas such as the gaps
around access a nd landing gear doors, flushness
of fasteners, and alianment of rivet includina
continuous and spo iwe ldment pa tterns ~ i h r e
6.12).
Soviet equipment show s the extensive use of
welded fittings in combination w ith numerous
castings and forgings in order to limit complex
machining Figure 6.13 .
Airframe structures are designed around materials
that work at low stresses and are assembled
through use of both spot and continuous welding
Figure 6.1
4 .
Western aircraft designers seldom
use spot welding because of its limited fatigue life,
but if aircraft are frequently overhauled weldments
can be inspected and replaced in a timely manner.
Because of the liberal use of weldments, Soviet
aircraft have several nonrepairable parts, however,
and these are replaced by exchanging entire
subassemblies during the frequent overhauls.
Figure 6.12 This weld-bond ed MiG-29 Fulcrum access panel is typical of most doors on the aircraft. Note the
misaligned spot weld pattern.
1 8
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Su 27 Flanker
Figure
6 13
Landing gear struts are typically fabricated of several small welded forgings to facilitate required non
aligned placement of lugs and the trunnion.
Simple designs are inherently more rel iable and
rugged; for instance, in systems with
low arts
count. For
example, the R -11 turbojet engine that poke rs the M~ G- ~I
Fishbed fighter has a l i t t le over 5000 parts
-
impressive
when compared to the 30,000 parts in the
F-4
Phantom s
J-79, an engine of the same era and thrust class (Figure
6.15 .
B
HEREDITY ND COMMON LITY
Soviet designers develop each new system by the
careful metering of modifications to the previous design.
In this way, the Soviet designer can minimize develop-
ment disruptions
bv
allowina onlv limited amounts of ad-
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PARTS COUNT FOR SEVER WESTERN
I
4 0 .
0 50 100 500 1000
ENGINE INLET AIRFLOW -LB/SEC
Figure 6.15 Soviet engines are designed with derated systems and easy removal of modularized high failure parts.
Premium castings are extensively used to reduce parts
aircraft. In the MiG family evolution, each design incorpo-
rates many design features and components of its prede-
cessors, or even several predecessors (Figure 6.16). One
possible drawback to design heredity is the necessity for
the continuity of a single design team to sustain the corpo-
rate knowledge. This long-term team continuity has the
possibility of causing design stagnation resulting from the
continuing restraints of the older designers. This mind-set
possibility, however, is seen by the Soviets as less a
problem than organizing a new design team bringing only
limited corporate knowledge to each new design.
Design commonality is closely related to heredity
since the designer applies actual components of concur-
rent and previous aircraft to current prototypes, to reduce
new, therefore higher risk, systems per program. This
concept can apply to complete aircraft assemblies, such
as wings or empennages, or to smaller compon ents such
as instruments, pumps or actuators. The smaller compo-
nents could actually be considered standard parts how-
ever, Soviet standard parts lists usually are compilations
of simple parts such as fasteners, fittings, extrusions, etc.
The classic example of the application of common
aircraft assemblies to a new design is with the develop-
ment of the Su-15 Flagon intermediate-range interceptor
in early 1970 s. The Flagon prototype was a marriage of
two R13-300 engines from the MiG-21 Fishbed; the wing,
horizontal and vertical tails, and canopy from the Su-9/11
Fishpot; and the RP11 (Skip Spin) radar from the Yak-28P
Firebar with the only original development being the
fuselage (Figure 6.17). In the same lineage, the swept
wing counterpart to the Su-9/11 Fishpot, the Su-7 Fitter,
was improved by adding a variable sweep wing and re-
named the Su-7 IG; the aircraft went to production as the
Su-17/20/22 Fitter- C/H.
Figure 6.1 7 The last example of extensive configuration
common ality w as the Su- 15 Flagon a combination of ex-
isting wings tails cockpit radar and engines. Only the
fuselage was all new.
1945 195 1955 1965 1975
Figure 6.16 Heredity is apparent in MiG fighter designs however configuration heredity is decreasing .
20
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Interestingly, with each new generation of aircraft,
Soviet designers are relying less on heredity and com-
monality as principal design tools. Soviet aircraft design-
ers are actually increasing the percentage of new tech-
no log ies and components in t roduced in to each new
mode l (Figure 6.18). The current genera tion of fighters,
including the Su-27 Flanker and MiG-29 Fulcrum, incor-
porate new airframes, engines, guns, radars and missiles,
194 195 196 197 198 199
Y E R
Figure
6.18
The emphasis on heredity as a p rincipal de-
sign approach i s inversely decreasing in proportion to the
t ime between ne w models.
the first time these systems have been concurrently devel-
oped for new aircraft models definitely a higher risk, non-
heredity approach.
Heredity, however, sti l l influences Soviet aircraft
design, but in mo re subtle forms:
The MiG
OK
incorporates several welded internal
structural assemblies while Sukhoi prefers riveted
assemblies.
MiG prefers constant radius canopy layout; Sukhoi,
the teardrop shape.
MiG prefers wing attachment lugs to be outside the
wing and fuselage lines; Sukhoi, inside.
MiG prefers extern al surfaces to be lofted with
straight line elemen ts and circles and straight lines
in cross section; Sukhoi employs more complex
surface shapes.
In commona lity, as with heredity, an increasing per-
centage of major components are unique to each design
however, small parts commonality is still widespread. The
common use of the same compo nents are most evident to
the Western observer in Soviet cockpit instruments.
The
Sirena II radar warning system in the M iG-29 Fulcrum, the
Su-25 Frogfoot and the Su-27 F lanker is the same one
developed for the 1950 s vintage MiG-21 Fishbed (Figure
6.19).
C CONFIGURATION ECONOMY
To ensure that production meets national objec-
tives and assets, the Soviet designer must balance perfor-
F igure
6.19
The communally emp loyed Sirena radar
warning system cockpit instrument still retains the MiG-21
Fishbed plan orm.
manc e against producibility. Whe reas heredity and com-
monality are design methods employed to reduce devel-
o p m e n t r i s k s b e f o r e p r o d u c t i o n , th e p e r f o r -
mance/production balance is the measure of program
cost effectiveness
--
configuration economy. One exam-
ple of design economy is found in the Soviet approach to
temperature-related, parameter-variations control in solid-
state equipment. The accepted method is to design cir-
cuits that are self-compensating. The Soviets chose to
provide microclimate enclosures in which the component
environment was protected from temperature and humid-
i ty var iat ions wi th on-board miniature ai r-condi t ion-
inglheating systems. In this way, a more complex, higher-
risk circuit design was avoided
by
incorporating a rne-
chanical solution.
Important elements of configuration economy are in
the judic ious appl icat ion of sta nd ard izat ion , rnod ular-
i ty , a nd r e d u n d a n c y .
Sta nd ard izat ion ensures the minimum variety
of equipment, optimizes the ability to interchange assem-
blies and components, and reduces training and logistics
requirements. Standard ization involves the use of ap-
proved parts l ists of components, assemblies, and sub-
sections wherever possible. An example of materials
standardization is the way the Soviets chose extrusions
for their designs. The available shap es and size of the
standard extrusions to the Soviet designer are very lim-
ited when compared to the variety available in the West.
The ones available are especially configured to overcome
that apparen t shortcoming. Bui l t -up structures are
reduced by incorporating skins and stringers, extruded as
one p art, throughout the aircraft as wing and tail skins, ac-
cess pan els, and, as fuselage skins (Figure 6.20).
Another special feature of the Soviet extrusion de-
sign is the cross-sectional geometry of several beams to
facilitate nesting with other extrusions or even rolled steel
bands. In this way, the designer has the choice of either a
standard extrusion to meet a particular structural need, or
if
the strength of the available sections are not optimum
then he can build up a near-optimum part by bonding
nested sections (Figure 6.21). In fact, the designer has
the choice of nesting such materials as an aluminum ex-
trusion with a stee l band. What would be a problem of
attaching dissimilar metals with the resultant corrosion is
not of great concern to the designer because he is de-
signing a relatively short-l ived weapon, and even if a
7/25/2019 FIGHTER DESIGN From Soviet Perspective
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Figure
6 20
Among the standard parts available to the
Soviet designer is skinkitringer extrusions. These extru-
sions are employed extensively as fuselage and wing
surfaces as well as access panels and wheel doors.
Figure
6 21
The Soviet designer has a limited but very
flexible choice of extruded memb ers.
problem develops it can be corrected during the frequent
overhauls.
Mo du larit y quantifies the size and complexity of
nonrepairable components. In the Soviet context, modu-
larity eliminates airbase-level type repairs and ensures
low parts count. For instance, with the S u-27 Flanker
engine, damaged modules can be replaced in the field
without replacing the whole engine. The Soviet military
press reported that in one air defense unit a modular low-
pressure compressor had been replaced at the regi-
mental intermediatetbase) level. On previous models,
the complete engine would have to be removed, crated,
and sent to a repair depot. The replacement would have
to be drawn from the material reserves.
An a dded design feature to meet the austere repair
environment of the dispe rsed airbase is that component
definition is based on failure frequency. In the Soviet jet
engines, the afterburner component can be
removed
while the turbine component is still in the aircraft.
In this
way that part of the engine which requires over
50
of all
repairs
--
the afterburner can be removed and replaced
in the field without having to disconnect the fuel, electrical,
or hydraulic lines Figure 6.22). With the failure-priority
design approach, field-level repairs are greatly simplified
and expedited. This design approach is especially effec-
tive in the repair of electrical, electronic, and hydraulic
systems components.
OTAL ENGINE REMOVAL REQUIRES COMPLEX SUPPORT PROCEDURE S
HOWEVER
LL
TH E A FTE R B U R N E R C ON S TI TU TE S OV E R
5 0 0 0
OF ALL TURBOJET MAINTENANCE ACTIONS
ND IF Ot lLY THE AFTERBURNE R IS REMOVED THEN ONLY FLIGHT LINE SUPPORT IS REQUIRED
Figure
6 22
Typically the replacement of a com plete
Soviet fighter engine is a very time consuming process;
however, the principal compo nents are modularized so
the high failure rate items c an be easily replaced-- even in
the field.
Re du nd an cy is usually defined as the provision
of duplicate, backup, or equivalent systems or compo-
nents to improve survivability, availability, and operability.
In Soviet terms, redundancy is defined as systems de-
signed to meet required tasks, not to optimum perfor-
mance. In other words, equipment degradation, not fail-
ure, is the primary design for redundancy consideration.
In avionics, circuits are designed to degrade before fail-
ure.
This approach ca lls for frequent inspection and cali-
bration, but fewer backup systems are required. This
same approach is also applied to mechanical systems
with the overdesign of all critical components to reduce
redundant and emergency systems. In mechanical sys-
tems, redundancy calls for very simple b ackup systems for
survivability and inflated margins of safety in the primary
systems for reliability.
The Soviet designers mandate is to ensure
sim
plicity in layout, simplicity in production, simplicity in
7/25/2019 FIGHTER DESIGN From Soviet Perspective
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VII COMME NTS AND CONCLUSIONS
The foundation of Soviet weapons acquisition is a
comprehensive and dyn amic m ilitary doctrine that defines
how future wars must be fought to be won and how the
nation's civilian and military sectors must be structured
and prepared in the eventuality of such a war.
Soviet military doctrine, the strongest influence on
the design characteristics of Soviet weapons, stresses
that future battles wil l be intensive and probably pro-
longed, with very high attrition rates needing a steady flow
of replacements. Consequently, Soviet planners require
that reliable weapons be quickly available in great num-
bers while being effectively operated and maintained by
conscripts in the extreme environment of w ar.
In peacetime, the Soviets maintain a unique form of
standing-start readiness with which they are able, at the
outset of a conflict, to immediately deploy operational
aviation units to, and employ from, austere dispersal
bases.
To meet the operational requirements, Soviet air-
craft are designed for a highly reliable, predetermined
(though relatively short) combat life to reduce wartime
maintenance on austere deployment bases. Some quar-
ters have questioned the viability of this concept because
of the apparent support complexity of modern weapons
however, Soviet aircraft and their support systems have
always been designed to achieve this capabil ity. The
question is in assump tions of the questioner. The prob-
lem is possibly in deman ding mirror images and ignor-
ing the extreme vulnerability of all fixed basing.
Soviet military thinkers have determine d that, to be
effective, weapons m ust be available in massive numb ers
(reserves) a nd b e highly supportable i n a wartime envi-
ronment. Additionally, the Soviets have conclu ded that
while w eapons ne ed only be adequate for a given m is-
sion, they shou ld be h ighly reliable for their postu lated
combat life.
R E F E R E N C E S :
This pa per is base d primarily on personal contacts
with several Soviet designers, pilots, and technicians in-
cluding close inspection of several of their current military
and civilian aircraft. Not only did the Soviets readily fur-
nished extensive information on their aviation industry but
they also supplied confirmation of several earlier postu-
lated design and operational features of Soviet aircraft.
Several published sources were also used in the
research for this paper; including some of mine. The fol-
lowing are several of the more useful.
Books:
Aviaexport; A viation Metallurgy of the US SR
Baxter, W. P.; The Soviet Way o f Warfare, Brassey
Eyermann, K. H ; MiG Flugzeuge, Transpress
IGDR)
blagle v, A. N ; Construction o f the Aircraft
Handbo ok for the Aviation R ear Specialist
Hemsley, John; Soviet Troop Control, Brassey
Matveyenko, A.
M ;
Airfield Braking S ystem of
Aircraft, Moscow Press
Soviet Military Encyclopedia
Taylor, John W.
R
ane's A ll the World's Aircraft,
Jane's Publishing
US Army FM 100-2-2
Vigor, P. H.; S oviet Blitzkrieg Theory, St. Martin's
Press
Reports and Papers;
Bodansky,Yossef; The Soviet Threat to N ATO Ai r
Bases, General Dynamics, 1989
Brower, K.S. and Kehoe, J.W.; U S an d Soviet
Weapons Systems Design Practices,
International Defense Review 6/1982
Director A/S Studies, Kirkland AFB, Strike Option
Comparison Study, ASCMDJSA
Lowy, S. H.; Im pact of Soviet Logistics Concerns
on Aircraft and Gas Turbine Design, Center for
Strategic Technology
Savkin, V. Ye. Bas ic Principles of Operational
Arts a nd Tactics, (USAF)
Soviet Army Studies Office; The Soviet Conduct
o f War, Fort Leavenworth, US Army
M a g a z i n e s ;
Air Force Magazine, Aviatsia i Kosmonautika (Soviet Air
Force Magazine), International Defense Review, Jane's
Defense Weekly, Lettecvi i Kosmonautika (Czechoslo-
vakian Air Force), Military Logistics Forum, Soviet Military
Review, Tyl i Snapzheniye (Soviet Military Logistics),
Tekhnika i Vooruzheniye, Vozdushny Transport
7/25/2019 FIGHTER DESIGN From Soviet Perspective
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operations and
simplicity
in support. In other words the
designer must satisfy production constraints and opera-
tional requirements with minimum complexity. Simplic
ity is found in all aspects of Soviet weapons acquisition
and operation because Soviet military planners believe
that to be effective weapons must first be simple.
Simple systems are inherently lower risk to develop less
costly to manufacture easier for conscripts to service and
repair and operators to use.
Recommended