1. THE 21 MAY AIRPLANE ENGINE FACTORY 2. THE ZRAK AIRPLANE ENGINE FACTORY

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP82-00457R011300120004-3
• Release Decision: RIPPUB
• Original Classification: S
• Document Page Count: 3
• Document Creation Date: December 19, 2016
• Document Release Date: March 15, 2006
• Sequence Number: 4
• Publication Date: April 7, 1952
• Content Type: REPORT

~ 1TF-Il i Approved For Release 2006/08/08: CIA-RDP82-00457RO11300120004-3
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. 51-""
FE8 1982
CLASSIFICATION SECtET/CONTROL - U.S. OFFICIALS ONLY
INFORMATION REPORT
25X1
COUNTRY Yugoslavia
SUBJECT 1. The 21 May Airplane Engine Factory
2a The Zrak Airplane Engine Factory
THIS DOCUMENT CONTAINS INFORMATION AFFECTING THE NATIONAL DEFENSE
OF THE UNITED STATES, WITHIN THE MEANING OF TITLE 18, SECTIONS 793
AND 794, OF THE U.S. CODE, AS AMENDED. ITS TRANSMISSION OR REVE-
LATION OF ITS CONTENTS TO OR RECEIPT BY AN UNAUTHORIZED PERSON 15
PROHIBITED BY LAW. THE REPRODUCTION OF THIS FORM IS PROHIBITED.
CD NO.
DATE DISTR. 7 April. 1952
NO. OF PAGES 3
NO. OF ENCLS.
(LISTED BELOW)
SUPPLEMENT TO
REPORT NO.
THIS IS UNEVALUATED INFORMATION
21 May Airplane Engine Factory
1. The 21 May Airplane Engine Factory (usually referred to as the 21 May-A
Enterprise to distinguish it from other factories in Yugoslavia with the
name of 21 May) is located in ap area near the fork of the Rakovica-Knezevac
and Rakovica-Monaatir Roads, close to Strazevica Mountain, between the towns
of Knezevac and Rakovica. The 21 May Airplane Engine Factory covers an area
of approximately 350 x 80 meters and is surrounded by a wall some two and one-
fifth meters in height. The area is patrolled by members of the KNOJ and the
industrial militia.
2. The Factory, construction of which was initiated in 1946, has not yet been
completed, although since August 1950,1 completion of airplane engine parts
has been carried out. Machinery, the majority of which is being furnished
25X1 is still in the process of installa-
tion. Factory buildings are not camp aged; the buildings and roofs are
unpainted.
3. The director of the 21 May Airplane Engine Factory has been identified as
Lieutenant Colonel Perekovic (or Petrovic); the deputy director is an uniden-
tified Yugoslav Air Force major and the technical director an unidentified
civilian engineer, presumably the only qualified engineer attached to the
21 May Factory. Employed in the technical department are three Yugoslav
Army captains, four Air Force captains and three Air Force majors, all
unidentified with the exception of a_certain Major Belovic, who was arrested
during the spring of 1951 on the charge of sabotage.
4. The 21 May Factory employs some 1,400 persons. Eight hundred of these employees
are civilians; 300 are ",nternal" apprentices; 150 are "external" apprentices;
and. the remaining 150 are military specialists. attached to various Army units.
A .0
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STATE
ARMY
CLASS I F I CAT I ON - SECRET TCONTROL ,- . S. 0 CT,S ONLY
NAVY
AIR
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An unspecified number of civilian employees at the 21 My Factory completed
apprentice courses in Czechoslovakia during 1948. The Factory operates on
two work shifts: one shift from. 7:00 a.m. to 2:30 p.m..,. and the other from
2:30 pom., to 11:00 p.m.
Construction at the 21. May Factory is under the control and. supervision of the
Vraniuak: Military Construction Enterprise, Belgrade.2 Approximately 400 soldiers
are occupied in this construction work at the Factory. The following construction
is still in process at the 21 May Factory:
An engine shop;
b. A transformer station; and
c. Excavation of tunnels under Strazevica Mountain.
6. The following interior constriction and installation is in process at the Factory:
a. Air-conditioning units are being installed in the various parts of the Factory;
b. Machinery is being installed in the various workshops;
c. Chemical laboratories are being equipped and fitted.;
d. The main building is beirsg_equ'ipped with sledge hammers;
e. The transformer station is being equipped with transformers and insulators;
f. Boilera and pipes are being installed in the boiler room; and,
g. Electrical, wiring is being completed.
All. machinery at the "1 May Factory will be electrically o ?er"ated . Electric
power will be furnished by an unidentified power station.
7. Inasmuch as the 21 May Airplane Engine Factory is not connected with the Kijevom
Resnik railway in the area, trucks are used for the transporting of eTuipment,
m terials and finished products. The following trucks, furs: }hed. with one
exception, by a truck supply depot located at Topcider, are at the disposal of
the 21 May Factory.
a. One Diamond-T truck, with a capacity of 25 quintals;
b. Two Skoda trucks with a capacity of 70 quintals;
c. One Prag . truck having a capacity of 25 quintals;
d. One German Ford V-_8 truck with a capacity of 25 quinta? ;
e. One British truck with a, capacity of 25 quintals; and
f. One tool truck on loan from the R.a.kovica Motor Factory.
8. While the 21 May Factory will not actually start serial production of airplane
engines until installations and construction have been entirely completed, the
following production w ?,s in progress during August 1951:
a. Manufacture of large goosenecks, possibly to be installed in engines, of
tanks. This work was limited to a single shift; one piece a week being
produced;"
b. Construction of gun sights derived from Mannesman gun barrels, 15 centimeters
long and one and one half-inches (sic) in caliber. Each sight bas becks. equipped
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with two lenses and a swallow-tailed base to clamp onto the gun barrel. The
Factory has received an order for the production of 20,000 pieces, and by
August 1951, 10,000 of these pieces had been completed and delivered to the
Kragujevac Military Arsenal;
c. Exhaust tubes, screws, nuts, cotter pins and other parts for airplane engines
are being produced; and
d. A model airplane engine, which was assembled during 1950 is on display in
the main building of the 21 May Factory. A second engine, completed during
the spring of 1951, is In the foyer of the directorate headquarters. Both
of these engines were tested at the testing shop of the Rakovica Motor Plant.
At the present time, workers in the main workshop are occupied with the completing
of semi-finished equipment and machinery, as follows:
Zrak Airplane Engine Factor
10. The Zrak Airplane Engine Factory, of recent construction, will produce star-
shaped airplane engines. This Factory which is located on the opposite side
of the mountain from the 21 May Factory in an area south of the Strazevica
Mountain,northeast of Kijevo, Belgrade, will be connected with the 21. May
Factory by an underground tunnel. This tunnel, now being excavated under
the Strazevica Mountain in a northeast to southwest direction, has an. entrarice
six by five meters in size on the side of the 21 May Factory. Fxcavatcd earth
from. the tunnel v ,-.s observed. lying along the western side of the Kijevo-Resnik
railway.
25X1 1. Comment. I
25X1 the 21 May Factory was put into
operation during the spring of 1949.
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