The Antonov An-70 (Ukrainian: Антонов Ан-70) is a four-engine medium-range transport aircraft, and the first aircraft to take flight powered only by propfan engines. It was developed in the late 1980s by the Antonov Design Bureau to replace the obsolete An-12 military transport aircraft. The maiden flight of the first prototype took place in December 1994 in Kyiv, now independent Ukraine. Within months the prototype had suffered a mid-air collision. A second airframe was produced to allow the flight-test programme to proceed. Both prototypes were produced by the Kyiv Aircraft Production Plant.

Following the dissolution of the Soviet Union in the early 1990s, the programme became a joint development between Russia and Ukraine. The former compounded the issue of a reduced market with its intermittent commitment to the project. Repeated attempts to start production have had limited success. Western European countries, including Germany, at one stage assessed the aircraft for procurement, but many later decided against it.

The origins of the An-70 can be traced back to the mid-1970s, when the Antonov Design Bureau began preliminary design work on a successor for the An-12 four-engine turboprop aircraft. The Soviet Armed Forces, by the 1980s, were looking for a replacement for the An-12 and a complement to the Ilyushin Il-76 four-engine jet transporter; in 1987, the Ministry of Defence, with a new emphasis on air mobility, specified an aircraft with a quick loading time, the ability to operate from short unprepared airfields, could carry up to 300 troops, and have good operating economy. The initial contract for work on the An-70 was concluded in May 1989; Antonov began advanced design work on the new aircraft during the same year. After the collapse of the Soviet Union, in June 1993, the Russian and Ukrainian governments agreed to jointly develop the An-70, with 80 percent of the funding expected to come from Russia. The following year, twenty companies and organisations from the former Soviet Union agreed to jointly develop, market and support the aircraft.

There were plans to establish mass ("serial") production of the model at the Kyiv Aircraft Production Plant (later renamed as the Antonov Serial Production Plant), which was associated with but separate from the Antonov Design Bureau, and at the Samara Aircraft Production Plant (later reorganised as Aviakor) in Samara, Russia. At one stage during early development, Russia was showing reluctance at supporting the development of the An-70, and so Uzbekistan sought, unsuccessfully, to establish a final assembly plant in the capital at the Tashkent Aircraft Production Plant, where the production of the An-70's wings and the Il-76 were taking place. Construction of the first prototype had started in Kyiv in 1991. The maiden flight of the aircraft had originally been scheduled for late 1992. However, due to financing and design issues, this was pushed back until 1994. In particular, the weakened national currency diminished the firm's ability to pay for the aircraft's components, especially those sourced from Russia, and workers' salaries. In addition, engineers discovered numerous design and manufacturing deficiencies during the final ground checks, the majority of which were non-critical yet necessitated lengthy corrections. In the end, the aircraft made its maiden flight on 16 December 1994.

Crewed by a seven-man team, the first aircraft performed a short take off from Svyatoshino Airfield, Kyiv. This was the first flight of an aircraft that was powered only by propfans. Due to worsening weather conditions over Antonov's headquarters and the flight test area in Kyiv, the flight was cut short, and the flight ceiling was capped at 2,000 m (6,600 ft). The crew took the aircraft to a height of 450 m (1,480 ft), while performing basic checkouts of the prototype's systems. After having been airborne for less than half an hour, the aircraft landed at Antonov's flight test facility at Hostomel. During the flight, engineers identified problems with the engine gearboxes, and so the aircraft was grounded for eight weeks while the issues were fixed.

Originally, the aircraft was to conduct flight tests at Hostomel for three months before transferring to the Gromov Flight Research Institute in Zhukovsky, near Moscow. However, the first prototype was lost when it was making its fourth flight on 10 February 1995. During the flight, the aircraft suffered a sudden deviation from its intended flightpath and collided with the An-72 chase plane before spiralling into the ground, erupting into flames; the test crew of seven were killed. Although there were initial allegations of technical issues with the aircraft, it was later determined that the crash had been caused by human error.

Antonov subsequently converted the static-test prototype into a flying prototype equipped with a modified flight-control system. The second airframe was rolled out in December 1996 in Kyiv, before making its first flight on 24 April 1997 from Svyatoshino Airfield, during which the aircraft was airborne for 31 minutes; according to Jane's, however, the aircraft had taken off from Hostomel for a 26-minute flight. The second prototype's initial flight nearly ended in disaster, as the flight-control system repeatedly malfunctioned. Test pilot Oleksandr Halunenko was forced to manually land the prototype, for which he was honored with the Hero of Ukraine title. By this time, more than US$2.5 billion had been spent on the programme, with a further $200 million to be spent to prepare the aircraft for production, which was expected to have started in 1999 with 20–25 aircraft produced annually. The Russian and Ukrainian Air Forces reportedly had long-term plans to procure 500 and 100 aircraft, respectively. The second airframe was severely damaged during cold weather testing on 27 January 2001 in a crash landing after take-off.

In the early 1990s, the An-70 was unsuccessfully considered as a platform to meet the European Staff Requirement (ESR) for the Future Large Aircraft (FLA) programme; the programme envisaged the development of a transport aircraft that is midway in size and capability between the Lockheed Martin C-130J and the McDonnell Douglas C-17 to replace the C-130 Hercules. In October 1997, however, the German Defence Minister Volker Rühe announced his intention to study whether the An-70 could be the basis for the FLA. The decision arose out of the German government's objective of providing industrial aid to and thus enhancing political ties with Eastern Europe. In December 1997, France, Germany, Russia and Ukraine agreed to evaluate the An-70 as a candidate for the FLA programme.