Soko J-21 Jastreb
{{Short description|Attack aircraft}}
{{Other uses|J21 (disambiguation){{!}}J21}}
{{Infobox aircraft
|name = J-21 Jastreb
|image = J-21 Jastreb Aerotehnički institut MF BG 3.jpg
|caption = A J-21 Jastreb on display at University of Belgrade, Department of Aerospace Engineering, 2019
|type = Light attack aircraft
|manufacturer = SOKO
|designer = Aeronautical Technical Institute (ATI)
|first_flight = 19 July 1965
|introduction =
|retired =
|status = Retired from Republika Srpska Air Force (2006)
|primary_user = Yugoslav Air Force
|produced = 1968–1977
|number_built = 224
|unit cost =
|developed_from = Soko G-2 Galeb
|variants =
}}
The Soko J-21 Jastreb (from {{lang-sr-Cyrl|јастреб|translation=hawk}}), referred to as the J-1 Jastreb in some sources, is a Yugoslav single-seat, single-engined, light attack aircraft, designed by the Aeronautical Technical Institute (ATI) and Military Technical Institute (VTI), in Belgrade, and manufactured by SOKO in Mostar. Derived from the G-2 Galeb advanced jet trainer and light attack aircraft, it was designed in single-seat ground-attack and two-seat advanced flying/weapon training versions.
Design and development
The J-21 Jastreb was developed as a replacement for the Republic F-84 Thunderjet, which had been the most commonly used turbojet fighter-bomber aircraft of the Yugoslav Air Force until 1967. On the basis of the G-2 Galeb, the J-21 Jastreb was developed as a single-seat, ground-attack variant, flying for the first time on 19 July 1965.
Pilots sit on licence-built Folland Type 1-B ejection seats under individual canopies hinged on the starboard side in unpressurised cockpits. Instruments and controls are entirely conventional with manually operated flying controls and standard flight instruments.
Powered by a single BWB licence-built Rolls-Royce Viper Mk531, the Jastreb has a conventional aluminium alloy stressed-skin structure with few or no special features. The relatively thick aerofoil section, though limiting performance, provides room for fuel cells, and the retracted main undercarriage which retracts inwards, gives the Jastreb a wide track with excellent ground-handling characteristics. The levered undercarriage legs and relatively low-pressure tyres allow the Jastreb to operate from unprepared strips or rough-surfaced airfields.
Compared to the Galeb, the Jastreb has a strengthened structure, allowing more weapons to be carried, including three {{convert|0.5|in|mm|abbr=on|1|order=flip}} Browning AN/M3 machine guns, mounted in the nose of the aircraft. Also, the Jastreb is able to carry up to {{convert|800|kg|lb|abbr=on}} on under-wing pylons, two inner pylons having a capacity of {{convert|250|kg|lb|abbr=on}} for bombs, rocket launchers, and additional tanks, while the six outer pylons can carry VRZ-157 {{convert|127|mm|in|abbr=on|2}} rockets. {{cn|reason=This entire design and development section needs a citation. I don't doubt the info, but no sourcing is an issue.|date=April 2024}}
Operational history
The J-21 entered service with the JRV (Yugoslavian Air Force) on 31 December 1968, with very few, if any, remaining in service.
=First Congo War=
{{Further|First Congo War}}
File:Zaire Jastreb.svg, with insignia erased to avoid confusion.]]
According to some reports, France and Yugoslavia supported Mobutu's government during the First Congo War.{{citation needed|date=October 2018}} Namely, Yugoslavia agreed to deliver three J-21s and a single G-2 aircraft, as well as four MiG-21PFMs, while three Mi-24s were purchased from Ukraine. All these aircraft were based at Gbadolite and flown mainly by Serbian mercenaries.
A Yugoslavian pilot, Ratko Turčinović, was killed while flying an ultra-low-level pass over Gbadolite, clipping a lamp post with his wing. The wreckage of his aircraft fell directly into a column of young soldiers on a parade, killing dozens. The accident is reported as being attributed to Turčinović's alcohol dependency.{{cite web|url=http://www.acig.info/CMS/?option=com_content&task=view&id=246&Itemid=47|title=Zaire/DR Congo 1980 - 2001 |website=acig.org|archive-url=https://web.archive.org/web/20150206225324/http://www.acig.info/CMS/?option=com_content&task=view&id=246&Itemid=47|archive-date=February 6, 2015| first1= Tom|last1= Cooper |first2= Pit |last2=Weinert|first3= Jonathan|last3= Kyzer |first4=Albert|last4= Grandolini|access-date=27 December 2015}}
Soon after the accident, the Yugoslavian staff were expelled from the DRC and the Jastrebs were abandoned along with the Galebs. MiG-21s and Mi-24s, awaiting assembly by Russian or Ukrainian technicians at Gbadolite, were also abandoned and could still be seen on the ramp at Gbadolite in 2013.https://archive.today/20130410043748/http://airserbia.com/forum/viewtopic.php?t=1561{{cite web|url=http://cyrilaucongo.canalblog.com/albums/gbadolite/photos/17758024-le_controle.html|title=Le contrôle|access-date=27 December 2015}}{{cite web|url=http://cyrilaucongo.canalblog.com/albums/gbadolite/photos/17758033-mi_24_bis.html|title=Mi 24 bis|access-date=27 December 2015}}{{cite web|url=http://cyrilaucongo.canalblog.com/albums/gbadolite/photos/17758744-mil_mi_24_hind.html|title=Mil MI 24 Hind|access-date=27 December 2015}}{{cite web|url=http://cyrilaucongo.canalblog.com/albums/gbadolite/photos/17758746-nez_pointu.html|title=Nez pointu|access-date=27 December 2015}}{{cite web|url=http://cyrilaucongo.canalblog.com/albums/gbadolite/photos/17758738-mig_21_bis.html|title=MIG 21 bis|access-date=27 December 2015}}{{cite web|url=http://cyrilaucongo.canalblog.com/albums/gbadolite/photos/17758881-soko_j_21_jastreb.html|title=Soko J-21 Jastreb|access-date=27 December 2015}}
=Bosnia and Herzegovina=
Six J-21 Jastrebs of the Republika Srpska Air Force were engaged by USAF F-16s during Operation Deny Flight for violating the NATO-enforced no-fly-zone, in what is known as the Banja Luka incident. The USAF claimed four J-21s shot down by F-16s, while the Serbs claimed five Jastrebs as lost. The discrepancy likely stems from a damaged Jastreb crashing near the airfield after the F-16s had departed.
On 15 November, during the Battle of the Dalmatian Channels, at 9:28 am, three Yugoslav Air Force J-21 Jastrebs flew low over Brač and Šolta; minutes later, two were reportedly shot down by anti-aircraft artillery. Six Yugoslav jets were sortied against targets on Brač and Šolta.
Variants
;J-21 Jastreb: Single-seat ground-attack, reconnaissance aircraft
;J-21E Jastreb: Export version of the J-1
;RJ-21 Jastreb: Single-seat tactical reconnaissance aircraft
;RJ-21E Jastreb: Export version of the RJ-1
;NJ-21:Two-seat advanced flying trainer / weapons trainer / light ground-attack aircraft
Operators
=Former operators=
File:J-21 Jastreb 24235 spomenik 235 LBAE 98 VBR 02.jpg
;{{flag|Republika Srpska}}
- operated 12 J-21 for training and for ground attack
;{{flagicon|Libya|1977}} Libyan Jamahiriya
;{{YUG}}
;{{ZAI}}:
;{{flag|Zambia}}
;{{LBY}}:
Aircraft on display
=Serbia=
;J-21/RJ-21
:The original prototype and over 31 J-21s are located at the Museum of Aviation in Belgrade.{{cite web|url=http://www.aviationmuseum.eu/World/Europe/Serbia/Belgrade/Muzej_Ratnog_Vazduhoplovstva.htm|title=Muzej Yugoslovenskog Ratnog Vazduhoplovstva: Museum of the Yugoslav Air Force|publisher=Aviation Museum|date=12 August 2009}}
Specifications (J-21 Jastreb)
{{Aircraft specs
|ref=[http://www.vojska.net/eng/armed-forces/equipment/aircraft/soko/j-21/ J-1 Jastreb (Hawk)] Vojska.net
|prime units?=met
|genhide=
|crew=1
|capacity=
|length m=10.88
|length ft=
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|length note=
|span m=10.56
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|height m=3.64
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|wing area sqm=19.43
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|max takeoff weight kg=5,100
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|fuel capacity= {{convert|440|kg|lb|abbr=on}} internal fuel + {{convert|435|kg|lb|abbr=on}} in 2x {{convert|275|L|impgal USgal|abbr=on}} jettisonable wing-tip fuel tanks.
|lift kg=
|lift lb=
|lift note=
|more general=
|eng1 number=1
|eng1 name= BMB (Rolls-Royce/Bristol Siddeley) Viper Mk 531
|eng1 type=turbojet engine
|eng1 kw=
|eng1 hp=
|eng1 shp=
|eng1 kn=13.32
|eng1 lbf=
|eng1 note=
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|eng2 number=2
|eng2 name=JATO units
|eng2 type=solid-fuelled rockets
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|eng2 kn=4.45
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|max speed kmh=820
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|max speed note=
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|cruise speed kmh=740
|cruise speed mph=
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|cruise speed note=at {{convert|5000|m|ft|abbr=on}}
|stall speed kmh=
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|never exceed speed kmh=
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|range km=1520
|range miles=
|range nmi=
|range note=with tip tanks
|combat range km=
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|ferry range km=
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|endurance=
|ceiling m=12,000
|ceiling ft=
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|g limits=+8 -4
|roll rate=
|glide ratio=
|climb rate ms=21
|climb rate ftmin=
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|power/mass=
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|more performance=
|guns= 3 × {{convert|0.5|in|mm|abbr=on|1|order=flip}} Browning AN/M3 machine guns
|bombs=
- 2 × {{convert|250|kg|lb|abbr=on}} general-purpose bombs or
- 2 × {{convert|150|kg|lb|abbr=on}} cluster bombs or
- 2 × {{convert|120|kg|lb|abbr=on}} cluster fragmentation bombs
|rockets=6 × VRZ-157 {{convert|127|mm|in|abbr=on|2}} rockets
|missiles=
|hardpoints=8
|hardpoint capacity=inboard pylons (2 of) {{convert|250|kg|lb|abbr=on}}, outboard pylons (6 of) {{convert|50|kg|lb|abbr=on}}
|hardpoint rockets=
|hardpoint missiles=
|hardpoint bombs=
|hardpoint other=
- 2 × {{convert|150|L|impgal USgal|abbr=on}} napalm tank
- 2 × rocket pods each with 12x {{convert|55|mm|in|abbr=on|2}} rockets
|avionics=K-14C or K-14A gun sight
}}
See also
{{Portal|Aviation}}
{{aircontent
|related=
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References
{{Commons category}}
{{Reflist}}
{{SOKO aircraft}}
{{Military Technical Institute Belgrade}}
{{YAF aircraft}}
Category:1960s Yugoslav attack aircraft
Category:Military Technical Institute Belgrade
Category:Single-engined jet aircraft
Category:Aircraft first flown in 1965