of M-93K Irydas were delivered to the Polish Air Force; these were intended to be the production-standard version of the type. Unlike the five preceding units of the type that had been previously handed over, the M-93K model was powered by the PZL K-15 engines instead of the older PZL-5 units which had been adopted as an interim powerplant. Amongst other benefits, the more powerful K-15 engines almost doubled the Iryda's payload capacity. The K-15 engine was not considered to be a likely candidate for export sales of the Iryda; British engine manufacturer Rolls-Royce was at one stage working with PZL to certify its Viper engine to power the type. Controversy and curtailment While the Polish Armed Forces were heavily impacted by curtailed budgets during the 1990s, the service intended to take delivery of five M-93K aircraft by the end of 1995, while plans for purchasing an additional six-to-eight Irydas were publicly discussed. At the time, there was an acknowledged desire for "around 40" jet trainers; the Polish Navy had also sought new trainer aircraft at this time. On 1 December 1995, the Polish Government announced that the Polish Air Force would purchase no further aircraft due to it being too costly to continue. The Iryda's chief designer, Marek Potapowicz, openly stated that the programme's loss could lead to the collapse of PZL Mielec. That same month, a rival plan to procure second-hand Dassault/Dornier Alpha Jets for the Polish Air Force was officially suspended; the negative impact on Polish industry was apparently a major contributing factor to this decision. Nevertheless, competing trainers, including the Alpha Jet, Saab 105, and Aero L-39 Albatros, were demonstrated to Polish officials. PZL Mielec offered several improvements for the Iryda, including various aerodynamic improvements, such as leading-edge root extensions and trailing edge flaps, along with a costly SAGEM-sourced avionics suite. During January 1996, funding was redirected by the Polish Government to support the Iryda programme; this was to not only to acquire additional aircraft but to finance upgrades to both the avionics and the engines. The prior month's decision to terminate the programme's backing had reportedly been overruled by Prime Minister Jozef Oleksy. According to aerospace industry periodical Flight International, Polish Air Force officials at one point were claiming the Iryda fleet to have achieved the highest serviceability statistics in the air force's inventory. However, Colonel Janusz Karpowicz of the Deblin pilot-training school criticised the