Difference between revisions of "J21RA"

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{{Specs-Card|code=saab_j21ra}}
 
−
 
 
{{About
 
{{About
 
| about = Swedish jet fighter '''{{PAGENAME}}'''
 
| about = Swedish jet fighter '''{{PAGENAME}}'''
 
| usage = other versions
 
| usage = other versions
 
| link = J21 (Family)
 
| link = J21 (Family)
−
}}  
+
}}
 +
{{Specs-Card
 +
|code=saab_j21ra
 +
|images={{Specs-Card-Image|GarageImage_{{PAGENAME}}.jpg}}
 +
|cockpit=Cockpit_saab_j21ra.jpg
 +
}}
  
 
== Description ==
 
== Description ==
−
''In the description, the first part should be about the history of and the creation and combat usage of the aircraft, as well as its key features. In the second part, tell the reader about the aircraft in the game. Insert a screenshot of the vehicle, so that if the novice player does not remember the vehicle by name, he will immediately understand what kind of vehicle the article is talking about.''
+
<!-- ''In the description, the first part should be about the history of and the creation and combat usage of the aircraft, as well as its key features. In the second part, tell the reader about the aircraft in the game. Insert a screenshot of the vehicle, so that if the novice player does not remember the vehicle by name, he will immediately understand what kind of vehicle the article is talking about.'' -->
−
[[File:GarageImage_{{PAGENAME}}.jpg|420px|thumb|left]]
+
The '''{{Specs|name}}''' was Sweden's first jet powered aircraft, built on the existing [[J21 (Family)|J21 series]]. The former planes had to be altered a bit due to issues that came with installing a jet engine and would encounter a few issues in the initial stages, but these would later be resolved. It would not be until 10 March 1947 when it would have its first flight. It was less than adequate in a fighter role, but would perform better in an attacker role. The Swedish air force would used these jets between 1949 to 1957, when they would later be replaced by the [[J29 (Family)|J29]] and [[A28B]].
−
{{break}}
+
 
−
The '''{{Specs|name}}''' is a rank {{Specs|rank}} Swedish jet fighter {{Battle-rating}}. It was introduced in [[Update 1.95 "Northern Wind"]].
+
The {{PAGENAME}} was introduced in [[Update 1.95 "Northern Wind"]]. As a jet-powered version of the [[J21 (Family)|J21]], it is the Swedish introduction to jets. Due to equipping a jet engine, the {{PAGENAME}} comes with a higher maximum speed than its predecessor, the [[J21A-2]]; it can perform very well in capable hands as a hit and run jet, but it can also perform well if needed in a dogfight. Having a cannon and four heavy machine guns gives it similar firepower to the [[J21A-2]], which is adequate enough to deal with most enemies it will be up against. The {{PAGENAME}} is pretty user friendly, with a lot of ammunition, so mistakes when taking shots are not so costly, but there are also dangers due to it having a habit of easily tearing off its wings at high speeds. Fortunately, it comes with airbrakes that can slow the aircraft down fast enough in case it gets close to these dangerous levels of speed.
  
 
== General info ==
 
== General info ==
 +
[[File:J21RA Side view .png|left|thumb|325x325px|{{PAGENAME}} as seen from the side.]]
 +
The {{PAGENAME}} is a highly manoeuvrable plane, with a good climb rate. The guns, although a downgrade from the previous propeller-driven 13 mm version, still provide enough firepower to down most targets efficiently. The only downside is the airframe, which prevents the aircraft from reaching higher speeds. This is due to the engine being a bit too powerful for the plane, making it common to rip in straight lines and shallow dives. Luckily the {{PAGENAME}} features air-brakes, helping it slow down more effectively, allowing it to fight comfortable at the desired speed range.
 +
 +
The plane is an overall great introduction for anyone looking to learn to fly jet aircraft, as the vehicle handles very similar to its propeller-driven counterpart, while at a much higher speed than before.
 +
 
=== Flight performance ===
 
=== Flight performance ===
−
''Describe how the aircraft behaves in the air. Speed, manoeuvrability, acceleration and allowable loads - these are the most important characteristics of the vehicle.''
+
{{Specs-Avia-Flight}}
 +
<!-- ''Describe how the aircraft behaves in the air. Speed, manoeuvrability, acceleration and allowable loads - these are the most important characteristics of the vehicle.'' -->
 +
The {{PAGENAME}} is distinctly different in looks and performance from all other planes found at the same BR-range. Along with the Yak-15, the Saab 21R is one of the two propeller-driven planes successfully converted into jet propulsion. Just like its Soviet counterpart, the solution comes at the cost of speed. Although a lot more powerful than the [[J21A-2]], it still has the same airframe limitations, resulting in good turn-rate. The climb-rate is also significantly improved due to the weight of the vehicle, resulting in good vertical energy with the ability to stall out slower opponents. Getting back down can prove difficult however, as the {{PAGENAME}} has a rip speed of just 800 km/h, which it can accidentally reach if not careful. To avoid this, the plane features a small set of air-brakes, which aids in maintaining a safe speed. Experienced pilots can find a good use for them, along with the powerful flaps, to force overshoots, or to out-turn propeller-driven opponents. Be careful with the engine however! The propulsion of the {{PAGENAME}} is very primitive, and suffers from fuel starvation during extreme manoeuvres, especially in negative G-loads. This can be fatal when fighting vertically, as the engine drops all power almost immediately, and has to spool back up again before reaching the same efficiency as before.
  
−
{| class="wikitable" style="text-align:center"
+
The flight performance is identical to that of the [[A21RB]], but with slightly less engine power, as the RM1 engine generates some 130 kgf less.
−
|-
+
 
−
! colspan="8" | Characteristics
+
{| class="wikitable" style="text-align:center" width="70%"
−
|-
+
! rowspan="2" | Characteristics
−
! colspan="8" | ''Stock''
+
! colspan="2" | Max Speed<br>(km/h at 4,000 m)
−
|-
+
! rowspan="2" | Max altitude<br>(metres)
−
! colspan="2" | Max Speed<br>(km/h at ?,??? m)
 
−
! rowspan="2" | Max altitude<br>(meters)
 
 
! colspan="2" | Turn time<br>(seconds)
 
! colspan="2" | Turn time<br>(seconds)
−
! colspan="2" | Rate of climb<br>(meters/second)
+
! colspan="2" | Rate of climb<br>(metres/second)
−
! rowspan="2" | Take-off run<br>(meters)
+
! rowspan="2" | Take-off run<br>(metres)
−
|-
 
−
! AB
 
−
! RB
 
−
! AB
 
−
! RB
 
−
! AB
 
−
! RB
 
−
|-
 
−
| ??? || ??? || {{Specs|ceiling}} || ??.? || ??.? || ?.? || ?.? || ???
 
 
|-
 
|-
−
! colspan="8" | ''Upgraded''
+
! AB !! RB !! AB !! RB !! AB !! RB
 
|-
 
|-
−
! colspan="2" | Max Speed<br>(km/h at ?,??? m)
+
! Stock
−
! rowspan="2" | Max altitude<br>(meters)
+
| 763 || 742 || rowspan="2" | {{Specs|ceiling}} || 25.1 || 25.9 || 18.0 || 17.3 || rowspan="2" | 850
−
! colspan="2" | Turn time<br>(seconds)
 
−
! colspan="2" | Rate of climb<br>(meters/second)
 
−
! rowspan="2" | Take-off run<br>(meters)
 
 
|-
 
|-
−
! AB
+
! Upgraded
−
! RB
+
| 837 || 799 || 23.0 || 24.0 || 24.4 || 21.0
−
! AB
 
−
! RB
 
−
! AB
 
−
! RB
 
−
|-
 
−
| ??? || ??? || {{Specs|ceiling}} || ??.? || ??.? || ?? || ?? || ???
 
 
|-
 
|-
 
|}
 
|}
  
 
==== Details ====
 
==== Details ====
−
{| class="wikitable" style="text-align:center"
+
{| class="wikitable" style="text-align:center" width="50%"
 
|-
 
|-
−
! colspan="5" | Features
+
! colspan="6" | Features
 
|-
 
|-
−
! Combat flaps
+
! Combat flaps !! Take-off flaps !! Landing flaps !! Air brakes !! Arrestor gear !! Drogue chute
−
! Take-off flaps
 
−
! Landing flaps
 
−
! Air brakes
 
−
! Arrestor gear
 
 
|-
 
|-
−
| X || X || X || X || X    <!-- ✓ -->
+
| ✓ || ✓ || ✓ || ✓ || X || X    <!-- ✓ -->
 
|-
 
|-
 
|}
 
|}
  
−
{| class="wikitable" style="text-align:center"
+
{| class="wikitable" style="text-align:center" width="50%"
 
|-
 
|-
−
! colspan="5" | Limits
+
! colspan="7" | Limits
 
|-
 
|-
−
! rowspan="2" | Wing-break speed<br>(km/h)
+
! rowspan="2" | Wings (km/h)
−
! rowspan="2" | Gear limit<br>(km/h)
+
! rowspan="2" | Gear (km/h)
−
! rowspan="2" | Combat flaps<br>(km/h)
+
! colspan="3" | Flaps (km/h)
 
! colspan="2" | Max Static G
 
! colspan="2" | Max Static G
 
|-
 
|-
−
! +
+
! Combat !! Take-off !! Landing !! + !! -
−
! -
 
 
|-
 
|-
−
| {{Specs|destruction|constructions}} || {{Specs|destruction|chassis}} || ??? || ~?? || ~??
+
| {{Specs|destruction|body}} || {{Specs|destruction|gear}} || 437 || 408 || 260 || ~11 || ~5
 
|-
 
|-
 
|}
 
|}
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{| class="wikitable" style="text-align:center"
 
{| class="wikitable" style="text-align:center"
 
|-
 
|-
−
! colspan="4" | Optimal velocities
+
! colspan="4" | Optimal velocities (km/h)
 
|-
 
|-
−
! Ailerons<br>(km/h)
+
! Ailerons !! Rudder !! Elevators !! Radiator
−
! Rudder<br>(km/h)
 
−
! Elevators<br>(km/h)
 
−
! Radiator<br>(km/h)
 
 
|-
 
|-
−
| < ??? || < ??? || < ??? || > ???
+
| < 450 || < 390 || < 420 || N/A
 
|-
 
|-
 
|}
 
|}
  
 +
==== Engine performance ====
 
{| class="wikitable" style="text-align:center"
 
{| class="wikitable" style="text-align:center"
 
|-
 
|-
−
! colspan="3" | Compressor (RB/SB)
+
! colspan="3" | Engine
 +
! colspan="4" | Aircraft mass
 +
|-
 +
! colspan="2" | Engine name || Number
 +
! colspan="2" | {{Annotation|Basic mass|Mass of the aircraft with pilot and engine oil, but no fuel or weapons load}} || colspan="2" | Wing loading (full fuel)
 +
|-
 +
| colspan="2" | Svenska Flygmotor RM1 || 1
 +
| colspan="2" | 3,550 kg || colspan="2" | 192 kg/m<sup>2</sup>
 +
|-
 +
! colspan="3" | Engine characteristics
 +
! colspan="3" | Mass with fuel (no weapons load) || rowspan="2" | Max Takeoff<br>Weight
 +
|-
 +
! Weight (each) || colspan="2" | Type
 +
! 6m fuel || 20m fuel || 22m fuel
 +
|-
 +
| 705 kg || colspan="2" | Centrifugal-flow turbojet
 +
| 3,764 kg || 4,169 kg || 4,262 kg || 5,000 kg
 
|-
 
|-
−
! colspan="3" | Setting 1
+
! colspan="3" | {{Annotation|Maximum engine thrust @ 0 m (RB/SB)|The maximum thrust produced by each engine, while mounted in the aircraft. NOTE: Thrust varies significantly depending on speed & altitude.}}
 +
! colspan="4" | Thrust to weight ratio @ 0 m (100%)
 
|-
 
|-
−
! Optimal altitude
+
! Condition || 100% || WEP
−
! 100% Engine power
+
! 6m fuel || 20m fuel || 22m fuel || MTOW
−
! WEP Engine power
 
 
|-
 
|-
−
| ?,??? m || ??? hp || N/A
+
| ''Stationary'' || 1,290 kgf || N/A
 +
| 0.34 || 0.31 || 0.30 || 0.26
 +
|-
 +
| ''Optimal'' || 1,290 kgf<br>(0 km/h) || N/A
 +
| 0.34 || 0.31 || 0.30 || 0.26
 
|-
 
|-
 
|}
 
|}
  
 
=== Survivability and armour ===
 
=== Survivability and armour ===
−
''Examine the survivability of the aircraft. Note how vulnerable the structure is and how secure the pilot is, whether the fuel tanks are armoured, etc. Describe the armour, if there is any, and also mention the vulnerability of other critical aircraft systems.''
+
[[File:J21 Armour Plating.png|450px|thumb|right|Protective components found in the '''{{PAGENAME}}'''.]]
 +
{{Specs-Avia-Armour}}
 +
<!-- ''Examine the survivability of the aircraft. Note how vulnerable the structure is and how secure the pilot is, whether the fuel tanks are armoured, etc. Describe the armour, if there is any, and also mention the vulnerability of other critical aircraft systems.'' -->
 +
 
 +
* 10 mm steel - Firewall armour plate
 +
* 10 mm steel - Firewall cover armour plate
 +
* 10 mm steel - Pilot's back armour plate
 +
* 60 mm bulletproof glass
 +
* Engine fire system (EFS)
 +
 
 +
In terms of protection, the pilot is well protected by metal plates and bulletproof glass. But the pilot's safety isn't the primary concern for the {{PAGENAME}}, as the tail section is incredibly vulnerable. This is due to the twin-boom design, making a tailstrike twice as likely. And since the tail connects to the wing-section, the plane tends to lose tail-control when struck by wing damage. The engine is very large in comparison to the rest of the plane, making it a common target. The {{PAGENAME}} should avoid all possible damage, as surviving large amounts of fire is highly unlikely. Pulling away from head-on engagements increases the survivability immensely. Avoiding the enemy airfield is also important, as the {{PAGENAME}} lacks the speed to keep it safe from flak fire.
 +
 
 +
=== Modifications and economy ===
 +
{{Specs-Economy}}
  
 
== Armaments ==
 
== Armaments ==
 +
{{Specs-Avia-Armaments}}
 
=== Offensive armament ===
 
=== Offensive armament ===
−
<!--''Describe the offensive armament of the aircraft, if any. Describe how effective the cannons and machine guns are in a battle, and also what belts or drums are better to use. If there is no offensive weaponry, delete this subsection.''-->
+
{{Specs-Avia-Offensive}}
−
{{main|Akan m/39A (12.7 mm)|Akan m/45 (20 mm)}}
+
<!-- ''Describe the offensive armament of the aircraft, if any. Describe how effective the cannons and machine guns are in a battle, and also what belts or drums are better to use. If there is no offensive weaponry, delete this subsection.'' -->
 +
{{main|Akan m/45 (20 mm)|Akan m/39A (12.7 mm)}}
  
 
The '''''{{PAGENAME}}''''' is armed with:
 
The '''''{{PAGENAME}}''''' is armed with:
  
−
* 1 x 20 mm Akan m/45 autocannon (140 RPG)
+
* 1 x 20 mm Akan m/45 cannon, nose-mounted (140 rpg)
−
* 2 x 12.7 mm Akan m/39A heavy machine gun - nose mounted (350 RPG)
+
* 2 x 12.7 mm Akan m/39A machine guns, nose-mounted (350 rpg = 700 total)
−
* 2 x 12.7 mm Akan m/39A heavy machine gun - wing mounted (325 RPG)  
+
* 2 x 12.7 mm Akan m/39A machine guns, wing-mounted (325 rpg = 650 total)
 +
 
 +
The {{PAGENAME}} shares the same 20 mm cannon found on the previous [[J21A-2]]. This cannon is near identical to the [[Hispano Mk.V (20 mm)|Hispano Mk.V]], only with a 30 rpm lower fire-rate. The shells perform the same as on all the other 20 mm-armed jets, making it highly devastating against all types of aircraft. The Armoured targets belt performs favourably with this cannon, as the Air targets belt can cause some mishaps during short bursts. The cannon runs out of ammunition quite quickly compared to the machine-guns, so saving it by only making use of the small calibre guns first can be ideal for spraying.
 +
 
 +
The {{PAGENAME}} features .50 cal machine guns, being identical to the later American ones. Although a direct downgrade from the Swedish 13 mm previously found on the plane, the {{PAGENAME}} makes good use of these cannons, as they allow for distanced engagements, along with additional firepower to back up the 20 mm cannon. Their ammo count is quite high as well, making them great for strafing, and finishing off heavy bombers.
  
 
== Usage in battles ==
 
== Usage in battles ==
−
''Describe the tactics of playing in an aircraft, the features of using vehicles in a team and advice on tactics. Refrain from creating a "guide" - do not impose a single point of view, but instead, give the reader food for thought. Examine the most dangerous enemies and give recommendations on fighting them. If necessary, note the specifics of the game in different modes (AB, RB, SB).''
+
<!-- ''Describe the tactics of playing in the aircraft, the features of using aircraft in a team and advice on tactics. Refrain from creating a "guide" - do not impose a single point of view, but instead, give the reader food for thought. Examine the most dangerous enemies and give recommendations on fighting them. If necessary, note the specifics of the game in different modes (AB, RB, SB).'' -->
 +
 
 +
* Climb to altitude
 +
* Energy-fight opponents by lowering their speed
 +
* Boom & Zoom people below you
 +
* Dogfight slow targets when necessary
 +
* Fire machine guns and cannons separately to save ammo
 +
 
 +
[[File:J21RA formation.png|thumb|331x331px|Two {{PAGENAME}} flying in formation.]]
 +
Despite being jet-powered, the {{PAGENAME}} still performs best when played like a propeller driven aircraft. The airplane struggles to reach high speeds, and drops it fairly quickly when manoeuvring. So the best use of the new engine is to gain altitude. Although weak in performance compared to earlier jets, the {{PAGENAME}} is decent at climbing to altitude, and can very efficiently deal with targets thanks to the high agility offered at lower speeds. Although the flaps are designed for much lower speeds (similar to the J21A-2), the plane still performs similar to the propeller variant when turning, making them less desired than on other jets.
  
−
=== Manual Engine Control ===
+
The best way to start a match is to immediately gain altitude. A height advantage around 5 km is usually ideal to avoid losing vital speed when fighting, as the plane can simply dive to gain more velocity. The best way to handle opponents, is to single them out from their team, and forcing them to dogfight, as the {{PAGENAME}} is too slow to chase anyone down. The {{PAGENAME}} is also efficient against propeller aircraft, as it can comfortably turn-fight, while keeping a higher speed. When paired with the devastating firepower it provides, the {{PAGENAME}} becomes deadly when used properly.
−
{| class="wikitable" style="text-align:center"
 
−
|-
 
−
! colspan="7" | MEC elements
 
−
|-
 
−
! rowspan="2" | Mixer
 
−
! rowspan="2" | Pitch
 
−
! colspan="3" | Radiator
 
−
! rowspan="2" | Supercharger
 
−
! rowspan="2" | Turbocharger
 
−
|-
 
−
! Oil
 
−
! Water
 
−
! Type
 
−
|-
 
−
| Not controllable || rowspan="2" | Not controllable<br>Not auto controlled || rowspan="2" | Not controllable<br>Auto control available || rowspan="2" | Not controllable<br>Auto control available || rowspan="2" | Separate || rowspan="2" | Not controllable<br>1 gear || rowspan="2" | Not controllable
 
−
|-
 
−
|}
 
  
−
=== Modules ===
+
The {{PAGENAME}} can be used in combined battles (Ground RB & Ground SB), but is overall less efficient compared to the [[A21RB]], as it lacks suspended armaments.
−
{| class="wikitable"
 
−
! colspan="1" | Tier
 
−
! colspan="2" | Flight performance
 
−
! colspan="1" | Survivability
 
−
! colspan="2" | Weaponry
 
−
|-
 
−
| I
 
−
| Fuselage repair
 
−
| Radiator
 
−
|
 
−
|
 
−
|
 
−
|-
 
−
| II
 
−
|
 
−
| Compressor
 
−
| Airframe
 
−
|
 
−
|
 
−
|-
 
−
| III
 
−
| Wings repair
 
−
| Engine
 
−
|
 
−
|
 
−
|
 
−
|-
 
−
| IV
 
−
|
 
−
|
 
−
| Cover
 
−
|
 
−
|
 
−
|-
 
−
|}
 
  
 
=== Pros and cons ===
 
=== Pros and cons ===
−
''Summarise and briefly evaluate the vehicle in terms of its characteristics and combat effectiveness. Mark its pros and cons in the bulleted list. Try not to use more than 6 points for each of the characteristics. Avoid using categorical definitions such as "bad", "good" and the like - use substitutions with softer forms such as "inadequate" and "effective".''
+
<!-- ''Summarise and briefly evaluate the vehicle in terms of its characteristics and combat effectiveness. Mark its pros and cons in the bulleted list. Try not to use more than 6 points for each of the characteristics. Avoid using categorical definitions such as "bad", "good" and the like - use substitutions with softer forms such as "inadequate" and "effective".'' -->
  
 
'''Pros:'''
 
'''Pros:'''
−
*
+
 
 +
* Highly manoeuvrable, competes with propeller driven aircraft
 +
* Familiar layout for seasoned Swedish pilots, same gun placement as previous Saab 21s
 +
* Useful airbrakes, good at avoiding higher speeds
 +
* No wing-tanks compared to the [[A21RB]]: Less likely to be set on fire
 +
* Access to modern 12.7 mm rounds, highly efficient at dealing damage
  
 
'''Cons:'''
 
'''Cons:'''
−
*
+
 
 +
* Low top speed, can't reach 800 km/h without tearing off its wings
 +
* Downgraded armament: 12.7 mm machine guns instead of the old 13 mm
 +
* Small fuel tank with limited fuel choice: either 21 or 6 minutes of fuel
 +
* Engine prone to fuel starvation: negative G manoeuvres turn the engine off
 +
* Weaker engine compared to the A21RB
  
 
== History ==
 
== History ==
−
''Describe the history of the creation and combat usage of the aircraft in more detail than in the introduction. If the historical reference turns out to be too long, take it to a separate article, taking a link to the article about the vehicle and adding a block "/ History" (example: <nowiki>https://wiki.warthunder.com/(Vehicle-name)/History</nowiki>) and add a link to it here using the <code>main</code> template. Be sure to reference text and sources by using <code><nowiki><ref></nowiki></code>, as well as adding them at the end of the article. This section may also include the vehicle's dev blog entry (if applicable) and the in-game encyclopedia description (under <code><nowiki>=== In-game description ===</nowiki></code>, also if applicable).''
+
<!-- ''Describe the history of the creation and combat usage of the aircraft in more detail than in the introduction. If the historical reference turns out to be too long, take it to a separate article, taking a link to the article about the vehicle and adding a block "/History" (example: <nowiki>https://wiki.warthunder.com/(Vehicle-name)/History</nowiki>) and add a link to it here using the <code>main</code> template. Be sure to reference text and sources by using <code><nowiki><ref></ref></nowiki></code>, as well as adding them at the end of the article with <code><nowiki><references /></nowiki></code>. This section may also include the vehicle's dev blog entry (if applicable) and the in-game encyclopedia description (under <code><nowiki>=== In-game description ===</nowiki></code>, also if applicable).'' -->
 +
The J21RA is a variant of the Saab 21R, a unique early jet fighter developed from the previous Saab 21. The aircraft was one of two semi-successful conversions of propeller fighters into jet fighters, the other being the Soviet Yak-15 (which was converted from the Yak 1/3/7/9 series). The aircraft served as one of the first jet-engined aircraft in Swedish service and was also the first jet-engined-aircraft produced by Saab. The Saab 21Rs were retired in the 1950s with the introduction of more advanced Swedish aircraft.
 +
 
 +
During WWII, the Saab aircraft production company produced the Saab 21, a fighter aircraft with an unorthodox twin-boom configuration along with a German DB 605B engine. The first such aircraft flew in July of 1943 and entered service soon thereafter. During this time, the Saab firm explored various options for upgrading their Saab 21s, including a variant powered by a Rolls-Royce Griffon engine producing 2000 hp. However, at the same time, the Saab firm was also investigating the possibility of a jet-engined fighter; this led the Saab firm to pursue a jet-engined variant of the Saab 21 for use with the Swedish air force.
 +
 
 +
In 1947, Saab received the first older J21 airframes for conversion into a jet fighter, designated the J21R; the airframes were extensively modified to house a British-sourced de Havilland Goblin turbojet in place of the DB 605 and its corresponding propeller. Extensive modifications were also made to the aircraft's fuselage, wings and tailplane; notably, the tail section was redesigned so that the elevator would be clear of the jet engine's exhaust. Additionally, the aircraft featured an ejection seat, a novelty at the time.
 +
 
 +
Initially, a production run of 124 aircraft was planned; however, this was cut to 64 aircraft when the more-advanced J29 Tunnan became available in 1948. The J21RA was the designation given to the first 34 of these aircraft, powered by the Goblin 2 engine, while the J21RB was powered by an indigenously-built Goblin 3 engine. The J21 was retired in the mid-1950s with the introduction of more advanced aircraft such as the Saab 32 Lansen; no original aircraft were preserved but an old Saab 21 airframe was converted to resemble the Saab 21R; this aircraft is displayed at the Swedish Air Force Museum.
  
 
== Media ==
 
== Media ==
−
''Excellent additions to the article would be video guides, screenshots from the game, and photos.''
+
<!-- ''Excellent additions to the article would be video guides, screenshots from the game, and photos.'' -->
−
<!--;Images
+
 
 +
;Skins
 +
 
 +
* [https://live.warthunder.com/feed/camouflages/?vehicle=saab_j21ra Skins and camouflages for the {{PAGENAME}} from live.warthunder.com.]
  
−
<div><ul>
+
;Videos
−
<li style="display: inline-block;"> [[File:(Insert image name.jpg/png here|thumb|none|250px|]] </li>
+
{{Youtube-gallery|JZcfQqbYWQk|'''Slap a Jet Engine on a Prop? J21RA''' - ''Jengar''|7vSoGWcb5zs|'''The Swedish Jet No Ones Talking About''' - ''WhooptieDo''}}
−
<li style="display: inline-block;"> [[File:(Insert image name.jpg/png here|thumb|none|250px|]] </li>
 
−
<li style="display: inline-block;"> [[File:(Insert image name.jpg/png here|thumb|none|250px|]] </li>
 
−
<li style="display: inline-block;"> [[File:(Insert image name.jpg/png here|thumb|none|250px|]] </li>
 
−
</ul></div>
 
  
−
;Videos-->
 
 
== See also ==
 
== See also ==
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{{Template:Sweden_jet_aircraft}}
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* [https://forum.warthunder.com/index.php?/topic/480524-j21ra/ Official data sheet - more details about the performance]
  
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[[Category:Sweden aircraft]]
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{{AirManufacturer Saab}}
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{{Sweden jet aircraft}}

Latest revision as of 20:10, 22 November 2023

Rank 7 USA
F-5C Pack
This page is about the Swedish jet fighter J21RA. For other versions, see J21 (Family).
J21RA
saab_j21ra.png
GarageImage J21RA.jpg
360://https://wiki.warthunder.com/images/c/c9/Cockpit_saab_j21ra.jpg
J21RA
Sweden flag.png Sweden
V Rank
Battle rating:
AB RB SB
6.7 6.7 6.7
Class:
Research:82 000 Specs-Card-Exp.png
Purchase:240 000 Specs-Card-Lion.png
Show in game

Description

The J21RA was Sweden's first jet powered aircraft, built on the existing J21 series. The former planes had to be altered a bit due to issues that came with installing a jet engine and would encounter a few issues in the initial stages, but these would later be resolved. It would not be until 10 March 1947 when it would have its first flight. It was less than adequate in a fighter role, but would perform better in an attacker role. The Swedish air force would used these jets between 1949 to 1957, when they would later be replaced by the J29 and A28B.

The J21RA was introduced in Update 1.95 "Northern Wind". As a jet-powered version of the J21, it is the Swedish introduction to jets. Due to equipping a jet engine, the J21RA comes with a higher maximum speed than its predecessor, the J21A-2; it can perform very well in capable hands as a hit and run jet, but it can also perform well if needed in a dogfight. Having a cannon and four heavy machine guns gives it similar firepower to the J21A-2, which is adequate enough to deal with most enemies it will be up against. The J21RA is pretty user friendly, with a lot of ammunition, so mistakes when taking shots are not so costly, but there are also dangers due to it having a habit of easily tearing off its wings at high speeds. Fortunately, it comes with airbrakes that can slow the aircraft down fast enough in case it gets close to these dangerous levels of speed.

General info

J21RA as seen from the side.

The J21RA is a highly manoeuvrable plane, with a good climb rate. The guns, although a downgrade from the previous propeller-driven 13 mm version, still provide enough firepower to down most targets efficiently. The only downside is the airframe, which prevents the aircraft from reaching higher speeds. This is due to the engine being a bit too powerful for the plane, making it common to rip in straight lines and shallow dives. Luckily the J21RA features air-brakes, helping it slow down more effectively, allowing it to fight comfortable at the desired speed range.

The plane is an overall great introduction for anyone looking to learn to fly jet aircraft, as the vehicle handles very similar to its propeller-driven counterpart, while at a much higher speed than before.

Flight performance

Air brakes
Allows you to dramatically reduce the flight speed by releasing special flaps
Max speed
at 4 000 m799 km/h
Turn time24 s
Max altitude12 192 m
EngineSvenska Flygmotor RM1
TypeJet
Cooling systemAir
Take-off weight5 t

The J21RA is distinctly different in looks and performance from all other planes found at the same BR-range. Along with the Yak-15, the Saab 21R is one of the two propeller-driven planes successfully converted into jet propulsion. Just like its Soviet counterpart, the solution comes at the cost of speed. Although a lot more powerful than the J21A-2, it still has the same airframe limitations, resulting in good turn-rate. The climb-rate is also significantly improved due to the weight of the vehicle, resulting in good vertical energy with the ability to stall out slower opponents. Getting back down can prove difficult however, as the J21RA has a rip speed of just 800 km/h, which it can accidentally reach if not careful. To avoid this, the plane features a small set of air-brakes, which aids in maintaining a safe speed. Experienced pilots can find a good use for them, along with the powerful flaps, to force overshoots, or to out-turn propeller-driven opponents. Be careful with the engine however! The propulsion of the J21RA is very primitive, and suffers from fuel starvation during extreme manoeuvres, especially in negative G-loads. This can be fatal when fighting vertically, as the engine drops all power almost immediately, and has to spool back up again before reaching the same efficiency as before.

The flight performance is identical to that of the A21RB, but with slightly less engine power, as the RM1 engine generates some 130 kgf less.

Characteristics Max Speed
(km/h at 4,000 m) 		Max altitude
(metres) 		Turn time
(seconds) 		Rate of climb
(metres/second) 		Take-off run
(metres)
AB RB AB RB AB RB
Stock 763 742 12192 25.1 25.9 18.0 17.3 850
Upgraded 837 799 23.0 24.0 24.4 21.0

Details

Features
Combat flaps Take-off flaps Landing flaps Air brakes Arrestor gear Drogue chute
✓ ✓ ✓ ✓ X X
Limits
Wings (km/h) Gear (km/h) Flaps (km/h) Max Static G
Combat Take-off Landing + -
787 360 437 408 260 ~11 ~5
Optimal velocities (km/h)
Ailerons Rudder Elevators Radiator
< 450 < 390 < 420 N/A

Engine performance

Engine Aircraft mass
Engine name Number Basic mass Wing loading (full fuel)
Svenska Flygmotor RM1 1 3,550 kg 192 kg/m2
Engine characteristics Mass with fuel (no weapons load) Max Takeoff
Weight
Weight (each) Type 6m fuel 20m fuel 22m fuel
705 kg Centrifugal-flow turbojet 3,764 kg 4,169 kg 4,262 kg 5,000 kg
Maximum engine thrust @ 0 m (RB/SB) Thrust to weight ratio @ 0 m (100%)
Condition 100% WEP 6m fuel 20m fuel 22m fuel MTOW
Stationary 1,290 kgf N/A 0.34 0.31 0.30 0.26
Optimal 1,290 kgf
(0 km/h) 		N/A 0.34 0.31 0.30 0.26

Survivability and armour

Protective components found in the J21RA.
Crew1 person
Speed of destruction
Structural787 km/h
Gear360 km/h
  • 10 mm steel - Firewall armour plate
  • 10 mm steel - Firewall cover armour plate
  • 10 mm steel - Pilot's back armour plate
  • 60 mm bulletproof glass
  • Engine fire system (EFS)

In terms of protection, the pilot is well protected by metal plates and bulletproof glass. But the pilot's safety isn't the primary concern for the J21RA, as the tail section is incredibly vulnerable. This is due to the twin-boom design, making a tailstrike twice as likely. And since the tail connects to the wing-section, the plane tends to lose tail-control when struck by wing damage. The engine is very large in comparison to the rest of the plane, making it a common target. The J21RA should avoid all possible damage, as surviving large amounts of fire is highly unlikely. Pulling away from head-on engagements increases the survivability immensely. Avoiding the enemy airfield is also important, as the J21RA lacks the speed to keep it safe from flak fire.

Modifications and economy

Repair costBasic → Reference
AB3 132 → 4 588 Sl icon.png
RB7 531 → 11 032 Sl icon.png
SB11 412 → 16 718 Sl icon.png
Total cost of modifications71 100 Rp icon.png
116 800 Sl icon.png
Talisman cost1 900 Ge icon.png
Crew training68 000 Sl icon.png
Experts240 000 Sl icon.png
Aces1 400 Ge icon.png
Research Aces620 000 Rp icon.png
Reward for battleAB / RB / SB
120 / 270 / 600 % Sl icon.png
184 / 184 / 184 % Rp icon.png
Modifications
Flight performance Survivability Weaponry
Mods aerodinamic fuse.png
Fuselage repair
Research:
7 100 Rp icon.png
Cost:
12 000 Sl icon.png
380 Ge icon.png
Mods jet compressor.png
Compressor
Research:
4 000 Rp icon.png
Cost:
6 500 Sl icon.png
210 Ge icon.png
Mods booster.png
New boosters
Research:
4 000 Rp icon.png
Cost:
6 500 Sl icon.png
210 Ge icon.png
Mods aerodinamic wing.png
Wings repair
Research:
5 900 Rp icon.png
Cost:
9 600 Sl icon.png
310 Ge icon.png
Mods jet engine.png
Engine
Research:
5 900 Rp icon.png
Cost:
9 600 Sl icon.png
310 Ge icon.png
Mods g suit.png
G-suit
Research:
5 800 Rp icon.png
Cost:
9 500 Sl icon.png
310 Ge icon.png
Mods armor frame.png
Airframe
Research:
4 000 Rp icon.png
Cost:
6 500 Sl icon.png
210 Ge icon.png
Mods jet engine extinguisher.png
EFS
Research:
5 800 Rp icon.png
Cost:
9 500 Sl icon.png
310 Ge icon.png
Mods armor cover.png
Cover
Research:
5 800 Rp icon.png
Cost:
9 500 Sl icon.png
310 Ge icon.png
Mods ammo.png
akan_m47_belt_pack
Research:
7 100 Rp icon.png
Cost:
12 000 Sl icon.png
380 Ge icon.png
Mod arrow 1.png
Mods ammo.png
bmg50_belt_pack
Research:
4 000 Rp icon.png
Cost:
6 500 Sl icon.png
210 Ge icon.png
Mod arrow 1.png
Mods weapon.png
akan_m47_new_gun
Research:
5 900 Rp icon.png
Cost:
9 600 Sl icon.png
310 Ge icon.png
Mods weapon.png
bmg50_new_gun
Research:
5 800 Rp icon.png
Cost:
9 500 Sl icon.png
310 Ge icon.png

Armaments

Offensive armament

Weapon 120 mm Akan m/45 cannon
Ammunition140 rounds
Fire rate725 shots/min
Weapon 24 x 12.7 mm Akan m/39A machine gun
Ammunition1 350 rounds
Fire rate768 shots/min
Main articles: Akan m/45 (20 mm), Akan m/39A (12.7 mm)

The J21RA is armed with:

  • 1 x 20 mm Akan m/45 cannon, nose-mounted (140 rpg)
  • 2 x 12.7 mm Akan m/39A machine guns, nose-mounted (350 rpg = 700 total)
  • 2 x 12.7 mm Akan m/39A machine guns, wing-mounted (325 rpg = 650 total)

The J21RA shares the same 20 mm cannon found on the previous J21A-2. This cannon is near identical to the Hispano Mk.V, only with a 30 rpm lower fire-rate. The shells perform the same as on all the other 20 mm-armed jets, making it highly devastating against all types of aircraft. The Armoured targets belt performs favourably with this cannon, as the Air targets belt can cause some mishaps during short bursts. The cannon runs out of ammunition quite quickly compared to the machine-guns, so saving it by only making use of the small calibre guns first can be ideal for spraying.

The J21RA features .50 cal machine guns, being identical to the later American ones. Although a direct downgrade from the Swedish 13 mm previously found on the plane, the J21RA makes good use of these cannons, as they allow for distanced engagements, along with additional firepower to back up the 20 mm cannon. Their ammo count is quite high as well, making them great for strafing, and finishing off heavy bombers.

Usage in battles

  • Climb to altitude
  • Energy-fight opponents by lowering their speed
  • Boom & Zoom people below you
  • Dogfight slow targets when necessary
  • Fire machine guns and cannons separately to save ammo
Two J21RA flying in formation.

Despite being jet-powered, the J21RA still performs best when played like a propeller driven aircraft. The airplane struggles to reach high speeds, and drops it fairly quickly when manoeuvring. So the best use of the new engine is to gain altitude. Although weak in performance compared to earlier jets, the J21RA is decent at climbing to altitude, and can very efficiently deal with targets thanks to the high agility offered at lower speeds. Although the flaps are designed for much lower speeds (similar to the J21A-2), the plane still performs similar to the propeller variant when turning, making them less desired than on other jets.

The best way to start a match is to immediately gain altitude. A height advantage around 5 km is usually ideal to avoid losing vital speed when fighting, as the plane can simply dive to gain more velocity. The best way to handle opponents, is to single them out from their team, and forcing them to dogfight, as the J21RA is too slow to chase anyone down. The J21RA is also efficient against propeller aircraft, as it can comfortably turn-fight, while keeping a higher speed. When paired with the devastating firepower it provides, the J21RA becomes deadly when used properly.

The J21RA can be used in combined battles (Ground RB & Ground SB), but is overall less efficient compared to the A21RB, as it lacks suspended armaments.

Pros and cons

Pros:

  • Highly manoeuvrable, competes with propeller driven aircraft
  • Familiar layout for seasoned Swedish pilots, same gun placement as previous Saab 21s
  • Useful airbrakes, good at avoiding higher speeds
  • No wing-tanks compared to the A21RB: Less likely to be set on fire
  • Access to modern 12.7 mm rounds, highly efficient at dealing damage

Cons:

  • Low top speed, can't reach 800 km/h without tearing off its wings
  • Downgraded armament: 12.7 mm machine guns instead of the old 13 mm
  • Small fuel tank with limited fuel choice: either 21 or 6 minutes of fuel
  • Engine prone to fuel starvation: negative G manoeuvres turn the engine off
  • Weaker engine compared to the A21RB

History

The J21RA is a variant of the Saab 21R, a unique early jet fighter developed from the previous Saab 21. The aircraft was one of two semi-successful conversions of propeller fighters into jet fighters, the other being the Soviet Yak-15 (which was converted from the Yak 1/3/7/9 series). The aircraft served as one of the first jet-engined aircraft in Swedish service and was also the first jet-engined-aircraft produced by Saab. The Saab 21Rs were retired in the 1950s with the introduction of more advanced Swedish aircraft.

During WWII, the Saab aircraft production company produced the Saab 21, a fighter aircraft with an unorthodox twin-boom configuration along with a German DB 605B engine. The first such aircraft flew in July of 1943 and entered service soon thereafter. During this time, the Saab firm explored various options for upgrading their Saab 21s, including a variant powered by a Rolls-Royce Griffon engine producing 2000 hp. However, at the same time, the Saab firm was also investigating the possibility of a jet-engined fighter; this led the Saab firm to pursue a jet-engined variant of the Saab 21 for use with the Swedish air force.

In 1947, Saab received the first older J21 airframes for conversion into a jet fighter, designated the J21R; the airframes were extensively modified to house a British-sourced de Havilland Goblin turbojet in place of the DB 605 and its corresponding propeller. Extensive modifications were also made to the aircraft's fuselage, wings and tailplane; notably, the tail section was redesigned so that the elevator would be clear of the jet engine's exhaust. Additionally, the aircraft featured an ejection seat, a novelty at the time.

Initially, a production run of 124 aircraft was planned; however, this was cut to 64 aircraft when the more-advanced J29 Tunnan became available in 1948. The J21RA was the designation given to the first 34 of these aircraft, powered by the Goblin 2 engine, while the J21RB was powered by an indigenously-built Goblin 3 engine. The J21 was retired in the mid-1950s with the introduction of more advanced aircraft such as the Saab 32 Lansen; no original aircraft were preserved but an old Saab 21 airframe was converted to resemble the Saab 21R; this aircraft is displayed at the Swedish Air Force Museum.

Media

Skins
Videos
Slap a Jet Engine on a Prop? J21RA - Jengar
The Swedish Jet No Ones Talking About - WhooptieDo

See also

Similar Swedish aircraft

Comparable Aircraft

External links


Swedish Aeroplane Company Ltd. (SAAB)
  Pre-SAAB: SA / ASJA
SA 'Jaktfalken'  J6B
SAAB 17  B17A · B17B · S17BS
SAAB 18  B18A · B18B · T18B · T18B (57)
SAAB 21  J21A-1 · J21A-2 · A21A-3 · J21RA · A21RB
SAAB 29 'Tunnan'  J29A · A29B · J29D · J29F
SAAB 32 'Lansen'  J32B · A32A · A32A Röd Adam
SAAB 35 'Draken'  J35A · J35D
SAAB 37 'Viggen'  JA37C · JA37D · JA37DI · JA37DI F21 · AJ37 · AJS37
SAAB 39 'Gripen'  JAS39A · JAS39C
SAAB 105  SK60B · SAAB-105G
License Production  B3C (Ju 86K)
Export  SAAB-105OE · J35XS · ▄JAS39C · ◔JAS39EBS HU C

Sweden jet aircraft
Fighters  J21RA
  J29A · A29B · J29D · J29F
  J32B
  J34
  J35A · J35D
  JA37C · JA37D · JA37DI · JA37DI F21
  JAS39A · JAS39C
Strike aircraft  A21RB
  A32A · A32A Röd Adam
  A28B
  AJ37 · AJS37
  SK60B · SAAB-105G
Export  SAAB-105OE
Finland  ▄Vampire FB 52A · ▄MiG-21bis · Saab J35XS

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