Is the New Klimov RD-93MA Engine an Option for the JF-17?

On 08 July 2020, United Engine Corporation (UEC) announced that one of its companies, Klimov, started testing its newly developed turbofan engine, the RD-93MA.[1] The RD-93MA is an improved variant of the RD-93, which powers the JF-17 Thunder, the mainstay multi-role fighter of the Pakistan Air Force (PAF).

Klimov will carry out tests on the RD-93MA at the P.I. Baranova (TsIAM) facility. Klimov will assess the RD-93MA’s behavior under simulated flight conditions. Later, it will proceed towards flight design tests.

According to UEC, the RD-93MA offers a range of improvements over the RD-93. These include “increased thermodynamic parameters” as well as improved fan design and automatic powerplant control system. It also improved the RD-93MA’s safety features – such as the addition of an emergency engine start mode – a necessity because the engine is meant for single-engine aircraft.

UEC was reportedly developing the RD-93MA since at least 2012, if not earlier.[2] In fact, UEC stated that it had gotten a request to develop the RD-93MA from a “foreign customer.” The RD-93MA was intended to offer a thrust of 9,300 kgf, a noticeable improvement over the RD-93’s 8,600 kgf.[3]

In addition, one could assume that the RD-93MA will also contain improvements from the RD-33MK (i.e., the improved variant of the RD-33), such as a full authority digital engine control (FADEC) system, longer time-between-overhaul (TBO), and a longer engine lifespan.

Though not explicit, it generally seems that the intended target customer of the RD-93MA is Pakistan, i.e., the largest user of the RD-93 (via the JF-17). However, it is unclear when those engine can factor into the JF-17 and, in light of the current geo-political environment, if the PAF will seek it.

Will Pakistan Seek the RD-93MA for the JF-17 Block-III?

The JF-17 Block-III is a significant upgrade over the Block-I and Block-II, and while an engine change would have made sense in some respects, it is unlikely the PAF will pursue a new powerplant at this stage.

According to PAF officials, the first two Block-IIIs are already under production, and the 50 aircraft are all due by 2024.[4] The PAF would not have started the Block-III’s production without securing a functional and certified turbofan engine. By UEC’s own admission, the RD-93MA is in its initial testing stage (and not yet ready for flight tests). Thus, the RD-93MA is not ready for integration and testing, much less deployment.

Moreover, in 2015, Pakistan Aeronautical Complex (PAC) officials clearly stated that the PAF was satisfied with the RD-93.[5] Klimov optimized the RD-93 with the PAF’s input, and the PAF currently views the RD-93 as “an ideal solution.”[6] Thus, the available indicators suggest that the PAF is retaining the RD-93.

The only scenario where the PAF could add the RD-93MA to the Block-III is if it opts to split the Block-III program into two parts, i.e., one with the RD-93 and another with the RD-93MA. However, the latter batch would come at a later timeframe than the originally scheduled 2023-2024. The coronavirus pandemic may be causing delays to the program, but an engine change will push timelines even further.

Is an Engine Change in the JF-17 Possible?

Though the PAF is satisfied with using the RD-93 onboard its current procurement run (i.e., a total of 162 single-seat JF-17 Block-I/II/III and 26 dual-seat JF-17Bs), it did not rule out an engine change.

In 2016, PAF officials said that they may consider the Chinese WS-13 or the Klimov RD-33MK as a method of improving the JF-17’s performance.[7] The mention of the RD-33MK could be an indirect reference to the RD-93MA, which was evidently in development at the time.

However, it is also clear that an engine change would not occur within the current roadmap of 188 JF-17s, including the 50 Block-IIIs and 26 JF-17Bs. Rather, the PAF could consider it for a follow-on, fourth tranche of JF-17s (e.g., ‘JF-17 Block-IV’) and subsequent variants.

This move would depend on whether the PAF sees a need for additional JF-17s past the Block-III and the JF-17B. Currently, there is no clear timeline regarding the development and deployment of Project Azm, i.e., the PAF’s next-generation fighter aircraft (NGFA) program. However, the Chief of Air Staff (CAS), Air Chief Marshal (ACM) Mujahid Anwar Khan said that the NGFA is unlikely to materialize before 2030.[8]

Be it a totally in-house program or even a consortium with a proven partner like China, the NGFA will run into its own delays and overruns, just as any modern fighter program would (including the JF-17. Thus, it would not be surprising if the timeline for the NGFA crosses well beyond 2030 and, potentially, closer to the late-2030s. So, the PAF may require a solution to supplant older aircraft in the interim.

In an earlier article, Quwa had argued that the PAF ought to continue developing the JF-17. The JF-17 can serve as a lower-cost supplement to support most air-to-air and air-to-surface/ground missions, especially as part of large-scale air operations involving large numbers of fighter aircraft.

However, there is an additional angle to the argument – i.e., extending the use of existing gains. The PAF has invested considerably in setting-up the infrastructure to operate the JF-17. It can extract more benefit from the overhead investment by spreading it across more aircraft. Likewise, the expense of setting-up a manufacturing line at PAC will also get more ‘mileage’ (so to speak) through an expanded order.

Moreover, the PAF has also invested in integrating a range of air-to-air and air-to-surface munitions to the JF-17. It may even be in the process of integrating the Ra’ad air-launched cruise missile (ALCM) to the JF-17 (especially the Ra’ad II, which has a more compact aft stabilizer stock that may fit under the wings of the JF-17). The PAF can carry these significant investments forward through additional JF-17 aircraft.

In this context, a new JF-17 variant equipped with the RD-93MA or WS-13 could make sense. In one sense, a JF-17 ‘Block-IV’ can serve as an interim solution until the availability of the NGFA. This course would help protect the PAF from the effect of technical difficulties and delays with the NGFA.

In fact, given how the NGFA is a twin-engine design (i.e., a medium-to-heavyweight aircraft), future JF-17 variants can also serve as lower-cost complements to the larger and more expensive aircraft. Interestingly, such an approach would not be different from how some in India envision using a potential Tejas Mk2 as a lower-cost support fighter to the Advanced Medium Combat Aircraft (AMCA).

Speaking of the Tejas Mk2, the PAF may also have the option to use an engine change as a catalyst to add more significant design changes to the JF-17. Like Hindustan Aeronautics Limited (HAL), the PAF can look at increasing the range and payload as well as decrease the fighter’s observability on radar.

Of course, the PAF is unlikely to carry such a project on its own, it would have to commission AVIC to take lead on the project. Realistically, there is no other way to imagine such an upgrade within the PAF’s fiscal and timeframe constraints. However, one obstacle to such a project could be from AVIC itself, which had developed the directly comparable J-10C, and the J-10C is now available for export as the J-10CE.

Thus, if there is to be a JF-17 ‘Block-IV’, it would likely be confined to at most an engine change alongside new subsystems and more modest airframe improvements. In other words, a ‘Block-IV’ would likely be a more iterative step from the Block-III more so than a different sub-platform (like the Tejas Mk2 is to the Tejas, or the way the JAS-39E/F is to the JAS-39C/D). In any case, follow-on JF-17 orders past Block-III and JF-17B are a realistic scenario, and the availability of the RD-93MA could add weight to such an outcome.

[1] Press Release. “The new engine for the development of the UEC will be tested in a thermal chamber TsIAM.” United Engine Corporation. 08 July 2020. URL: https://www.uecrus.com/rus/presscenter/odk_news/?ELEMENT_ID=3280

[2] “RD-33 Output on the Rise.” Take-Off Magazine. 2012. URL: https://web.archive.org/web/20121213192137/http://en.take-off.ru/news/107-june2012/729-rd33outputontherise

[3] Ibid.

[4] Alan Warnes. “JF-17 Thunder – Lightning Strikes Twice.” Air International Online. 15 June 2019. URL: https://www.ainonline.com/aviation-news/defense/2019-06-15/jf-17-thunder-lightning-strikes-twice

[5] Reuben F Johnson. “Pakistan to stick with RD-93 engine for JF-17, say PAF officials.” Jane’s Defence Weekly. 18 November 2015. URL: https://web.archive.org/web/20151224231601/http://www.janes.com/article/56105/pakistan-to-stick-with-rd-93-engine-for-jf-17-say-paf-officials

[6] Ibid.

[7] Richard D Fisher Jr. “DSA 2016: Pakistan bullish on JF-17 sales.” Jane’s Defence Weekly. 21 April 2016. URL: https://web.archive.org/web/20170124050712/http://www.janes.com/article/59661/dsa-2016-pakistan-bullish-on-jf-17-sales

[8] Alan Warnes. Interview with Air Chief Marshal Mujahid Anwar Khan, Chief of Air Staff, Pakistan Air Force. Jane’s Defence Weekly. 22 May 2019.