Japanese Defence Minister Itsunori Onodera has reaffirmed the nation's plan for a 2014 first flight of the Advanced Technology Demonstrator-X (ATD-X) fighter: a prototype for a future fighter to replace the Japan Air Self-Defence Force's Mitsubishi F-2.

"In February I myself visited at Mitsubishi Heavy Industries' (MHI's) Komaki Minami plant where the ATD-X is being built," Onodera told the Foreign Affairs and Defence Committee of the Upper House on 10 April. "There I was briefed that the first flight will take place this year."

The ATD-X, also known as Shinshin ('Heart of God'), is being developed by the ministry's Technical Research and Development Institute (TRDI), with the main contractor of the project being MHI. It has been designed to be a stealthy air-superiority fighter with enhanced manoeuvrability. The Japanese Ministry of Defence (MoD) will use it to research advanced technologies and system integration, after which it plans to produce a 'sixth-generation' fighter encompassing i3 (informed, intelligent and instantaneous) concepts and counter-stealth capabilities.

"Originally MHI planned to roll-out the ATD-X before the media in May, soon after Japan's Golden Week holidays, followed by the first test fight," an official at TRDI toldIHS Jane's on 15 April. "Now it is several months behind schedule."

Onodera also said in the Diet that the MoD will decide by FY18 whether to build its future stealth fighter domestically or by international joint development, based on parameters such as technological achievements and cost effectiveness.

Japan's plans to develop an 'F-3' from the ADT-X could run into opposition from the United States, however, which has blocked Tokyo's attempts to develop an indigenous fighter in the past.

The 1980s FSX support fighter programme was blocked by Washington, which pressured Tokyo over concerns that the growth of the Japanese aviation industry could damage that of the United States. The pressure eventually led to the co-development of the F-2: a platform based on the Lockheed Martin F-16C.

Officials said that with China and Russia deploying the Chengdu J-20 and Sukhoi PAK-FA T-50 fifth-generation aircraft respectively, Japan's development of a fast stealth fighter is becoming vital to national air defence.

"We know that our 28 radar sites are effective at detecting third- and fourth-generation fighters from a long distance, but with the appearance of fifth-generation fighters we are unsure how they will perform," Lieutenant General Hideyuki Yoshioka, then director of Air Systems Development at the TRDI, told IHS Jane's in November 2011.

The MoD allocated JPY2.7 billion (USD26.5 million) for research on radar and fire control systems able to detect, track and respond to stealth aircraft in FY14.