FACTUAL INFORMATION NITE 01, a United States Navy F-14 aircraft, had departed from the Atsugi Naval Air Facility, Japan on an Instrument Flight Rules (IFR) plan that included an exercise within Restricted Area R116. The restricted airspace R116 was used for military exercises, the northern end of which was approximately 6NM south east of the track of the B767. The F14 pilot cancelled his IFR status during his initial climb, choosing to proceed under Visual Flight Rules (VFR) procedures. The crew of the B767 were approaching flight level (FL) 250 while descending into Narita, Japan, when they received a Traffic Alert and Collision Avoidance System (TCAS) resolution advisory (RA) instruction to climb. During the transition from descent to climb, they saw a military aircraft passing in the opposite direction at high speed, approximately 500 ft below them. At approximately the same time, the air traffic controller observed radar returns from a VFR aircraft departing R-116 at FL250 and passed this information to the crew of the B767. He also contacted the pilot of the F-14 to establish that pilot's intentions. The B767 was climbing through FL255 (approximately) when the military aircraft passed. The rules for VFR flight in Japanese airspace were such that a pilot could choose to conduct a flight using a 500 ft separation standard up to FL290 without an airways clearance, provided a listening radio watch was maintained on air traffic control frequencies. These procedures allowed the pilot of the F-14 to leave R-116 under VFR and maintain his own separation, of at least 500 ft, from the B767. He stated that he had the B767 in sight and was listening on the control frequency. Therefore, he had complied with the 500 ft separation standard for VFR flight below FL290. The aircraft passed with approximately 500 ft vertical separation and no appreciable horizontal separation. ANALYSIS The TCAS advice to the B767 crew was a genuine alert as the respective flight paths were within the envelope for a RA alert. In this case, the crew manoeuvred their aircraft to a comparatively safe altitude, allowing the military pilot to pass beneath their aircraft. SAFETY ACTION As a result of the investigation, the Japanese Civil Aviation Bureau has requested the United States Air Force (the body responsible for overall military operations in the area) to remind all pilots under their jurisdiction of the proximity of IFR air routes and of the general civil airspace structure, and also to remind their pilots of the requirement to maintain adequate separation from civil aircraft. Additionally, the Japanese Bureau has asked for military training to be kept, as much as possible, within the specified training areas.