FIGHTER DESIGN From Soviet Perspective

7/25/2019 FIGHTER DESIGN From Soviet Perspective

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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


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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.


10/26

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-


11/26

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-


12/26


13/26

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.


14/26

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-


15/26

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


16/26


17/26

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-


18/26

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


19/26

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


20/26

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


21/26

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-


22/26

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


23/26

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


24/26

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


25/26

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


26/26

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.

Documents

FIGHTER DESIGN From Soviet Perspective