- Yes
- No
- Yes
- No
Overview
The TS-11 Iskra (spark) bis is a Polish jet trainer/ light multirole aircraft. Poland’s first indigenous jet aircraft, it was developed from 1957, first flew in 1960, and entered service in 1964. The Iskra bis D featured an improved SO-3B engine but otherwise was identical to the preceding Iskra bis B. The Iskra D was the first model to see export success, with 50 purchased by India in 1975, followed by 10 more in 1978. In addition to these 60 aircraft 101 were produced for domestic service.
Note on engines: All Iskra bis Ds were initially completed with SO-3B engines and later upgraded to SO-3Ws. As before, we will be looking at the SO-3B and saving the final SO-3W engine for the final Iskra DF model.
History
Expand
Development
Poland’s first jets were a trio of Yak-17s and 11 Yak-17UTI trainers purchased in 1950. As the Siły Powietrzne (Air Force, from here on abbreviated SP) acquired more jet aircraft (Yak-23s in 1951, production of MiG-15s in 1952) the need for a new basic jet trainer arose. In 1956, project requirements for the new TS-11 (named for lead designer Tadeusz Sołtyk) were laid out- the aircraft was to be of all-metal construction with a low, straight, thin wing, a top speed of Mach 0.8 and a conventional tandem cockpit layout with the student in the front and the instructor behind. The TS-11 was to be armed with a 23mm cannon for gunnery training or to allow the aircraft to operate as a fighter should global war break out.
A full-scale wooden mockup was built in late 1957. This was followed by a static test airframe in March 1959 and three proper flying prototypes from December 1959, all mounting the British Viper 8, acquired from Yugoslavia. The TS-11 made it first flight on 5th February 1960, being publicly debuted on 11th September 1960 in Łódź. The three prototypes underwent extensive testing late 1960 through 1961, proving easy to fly, agile, stable, reliable, and simple to maintain- in short, exactly what you’d want in a training aircraft.
Competition
So in August 1961 when the TS-11 was put up against the Soviet Yak-30 in a competition to become the standard jet trainer for Soviet allies, it dominated, outperforming the Yak in essentially every metric. This would be a massive deal for the Polish aviation industry.
However, there was a third contestant in the competition- the Czech L-29 Delfín. The L-29 was very similar to the TS-11 and nearly matched it in performance, all at a lower cost than the Polish aircraft. Because of this, the L-29 was selected as the standard primary jet trainer, and it and the subsequent L-39 were used by all close Soviet allies- except Poland, who continued forward with the TS-11.
Iskra A Into Service
Production of the TS-11 Iskra bis A began in 1964. Production aircraft were fitted with the HO-10, a copy of the Viper 8 with slight improvements that boosted its continuous power to 7.84kN. The first batch of 10 aircraft were handed over for trials in 1964. This was followed by two batches of 22 each in 1964 and 1965 respectively. Finally, in 1967, the last batch of 15 Iskra bis As (powered by the improved SO-1 as mentioned in the intro) entered production.
These aircraft had relatively uneventful service lives in SP service. The Iskra A was the least reliable of the family due to the HO-10 but still had a low accident rate.
The Iskra bis A achieved a series of four closed-circuit speed records for an aircraft in the 3000kg class.
Upping the Standard- the Iskra B
During this period the idea of a trainer/light attack aircraft was becoming very popular. Such an aircraft would provide increased strength in the event of war while being cheaper than separate trainer and light strike aircraft. Additionally, combat-capable trainers made training more realistic, allowing live-fire of actual weapons in service instead of simply simulators.
To this end the TS-11 Iskra bis B was developed with four underwing hardpoints for carrying ordinance, for training or combat. This aircraft had the SO-1 engine initially, later replaced by the more reliable but equally powerful SO-3. The Iskra bis B entered service in 1968, gradually replacing the Iskra As.
Refining the Spark- the Iskra D
The Iskra B had proved itself to be an excellent aircraft, but it still had room to grow. So, in 1972 development of the Iskra D began. All avionics were replaced by more modern models, and the SO-3 engine was replaced by an improved, more powerful SO-3B. The Iskra D was the first model to see export interest- in 1972, Iran evaluated the aircraft, and in 1973 Peru and India did as well. Of these countries, India would be the only one to actually purchase the TS-11. In 1975, 60 Iskra Ds were purchased; these aircraft would serve in the IAF from 1976 until 2004. Poland would receive the Iskra D the same year. The existing inventory of Iskra Bs would gradually be converted to Iskra D standard.
Almost Immortal Spark
The TS-11 had an extremely long service life, the longest for any armed single-engine jet in service of the country of origin. Simply, nothing could replace it. The first attempt to build a successor came with the TS-16 Grot of 1963, a supersonic aircraft (only the second supersonic trainer aircraft design in the world, preceded only by the T-38). This aircraft never saw production due to ballooning costs. The next attempt to replace the TS-11 came in 1976 with the I-22 Iryda. The Iryda was a subsonic twin-engine aircraft comparable to the Alpha Jet. This aircraft was actually produced and even entered service, and proved reliable, agile, and easy to fly just like the Iskra, while having substantially improved performance. However, the end of the Cold War and subsequent budget cuts killed the I-22 program in 1999 after only 28 built and 5 years of service. The I-22 would be the last indigenous Polish combat aircraft design. The next attempt to replace the TS-11 came in 2010, with the SP looking to purchase and license-produce the L-159 Albatros 2. This purchase was not pursued. The TS-11 would only begin being replaced in 2017, with the controversial purchase of the M-346 Bielik. While originally offered the M-346LCA, a modified version the the M-346FT, Poland instead opted for an unarmed version of the aircraft. This meant that many pilots were being deployed to their operational units without any actual weapons training, a significant issue only resolved in 2023 with the purchase of the FA-50GF. The final TS-11s were retired in 2021, 64 years after their first introduction.
Further Developments
The Iskra D was the penultimate new-build TS-11 model. It was followed by the Iskra DF, which featured the ultimate development of the original HO-10, the SO-3W. The DF also featured a trio of cameras for the reconnaissance role, taking after the Iskra C. Finally, in 1992, six DFs were refurbished and rebuilt to Iskra R standard for naval aviation. These aircraft received new avionics and were used primarily for naval reconnaissance.
Specifications
Expand
Airframe
Length: 11.25m
Span: 10.60m
Height: 3.50m
Empty Mass: 2,560kg
Loaded mass: 3,734kg
Wing Area: 17.50m^2
Crew: 2
Propulsion
1x SO-3B turbojet
Max thrust: 10.56kN
Internal Fuel: 1,200L across 4 self-sealing tanks
Flight Performance
Max Speed: 780km/h (Mach 0.63)
Climb Rate: 19.1m/s
Armament
1x NS-23 23mm cannon
23x115mm
115 rounds
600 RPM
720m/s
or interchangeably (can be swapped out in <30 minutes)
1x NR-23
23x115mm
150 rounds
900 RPM
720m/s
I’d have the NS-23 stock and NR-23 as a Rank I/II modification
Underwing hardpoints x4:
1x OFAB-100 100kg bomb
1x Mars-2 launcher (4x S-5)
1x Mars-4 launcher (8x S-5)
1x Zeus-1 gun pod
Pretty much every source mentions the Zeus-1 gunpod. However, the only information on the pod is that it has a calibre of 7.62mm.
Systems
RW-UM radar altimeter
Engine fire suppression system
KAP-3 ejection seats
The TS-11 Iskra bis D in-game
Expand
The TS-11 has pretty poor performance for an aircraft of its time because of its role as a trainer. However, it performs decently compared to first-gen jets. The Iskra would be a central part of a Polish air tree, helping to bridge the gap between wartime western equipment and post-cold-war western equipment. Compared to the preceding Iskra B, the Iskra D offers improved performance due to its more powerful engine.
Pros:
- Agile
- Decently fast
- Moderately powerful engine
- Decent rocket load for CAS
Cons:
- Mediocre climb rate
- Limited armament- NR-23 is an effective cannon but only a single cannon is rather poor
- Insufficient suspended armament for base bombing
Placement in a hypothetical Polish air tree
Gallery
Expand
In service the TS-11 D were primarily bare metal to lower weight, with coloured noses and tailtips
However, the Iskra Ds have also sported some more unconventional liveries, both in Polish service and private collections/museums
Additionally there is the lovely livery of the Red-White Sparks aerobatic team. They operated the special TS-11 MR, based on the TS-11 B but upgraded with more powerful engines as they became available. I believe this is justification enough for this skin for the B, D, and DF
TS-11 Ds in a live-fire exercise
The elusive Zues-1 pod
The TS-11 can be armed with Mars-2 or Mars-4 rocket pods, both shown here on a BR 200
Inside the front and rear cockpits. Avionics saw frequent upgrades so these should only be taken as a general layout
The Iskra D was the first model to see export, to the only export customer, India
Sources
Expand
Polskie Skrzydła- Polish Wings 36 TS-11 Iskra- Dariusz Karnas and Artur Juszczak
PZL TS-11 Iskra. 2008. - Polot
PZL TS-11 Iskra. 2009. - Polot
PZL TS-11 Iskra. 2010. - Polot
PZL TS-11 Iskra. 2011. - Polot
PZL-Mielec TS-11 Iskra two-seat low-wing jet trainer
Also check out the other members of the TS-11 family!
Iskra A
Iskra B
Iskra C
Iskra DF
Iskra R
Iskra BR 200
(links coming soon)