Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 108; Flight Crew Type 1978
Troubleshooting
Inflight Event / Encounter Unstabilized Approach; Inflight Event / Encounter Weather / Turbulence
Flight Crew Executed Go Around / Missed Approach
Human Factors; Weather
On approach to RJAA for ILS34L; ATIS reported surface winds (approximately) 310/24G28. Earlier; aircraft on both 34L and 34R had reported wind shear with +/- 10 and +/- 15 knots; respectively. This information was also on the arrival ATIS. We had an approach speed for Flaps 30 of 147 with a wind correction of +15 for a reference speed of 162. Passing approximately 500 AGL; a performance increasing wind shear occurred with the IAS noted at 175; right at the flap limit speed for Flaps 30. Throttles were reduced to correct the deviation; but at no time was idle thrust selected. By 300 feet AGL; speed was approximately 165-170 and fluctuating. Passing 200 feet AGL; we were on Glideslope with PAPIs showing one white and three red. We were within speed parameters for a stabilized approach and in a safe position to land. At this time the Ground Proximity Warning System (GPWS) gave several warnings of 'Too low; terrain'. At this time; we verified our configuration and noted the Flaps indicated 25 degrees; but the handle was in the 30 degree detent. Without delay; we executed a go around.The go around was uneventful and we were sequenced back to final with minimal delay after declaring 'minimum fuel' with approach control. Passengers were put at ease with a reassuring PA. The following approach had similar conditions; but reactions to the expected performance-increasing wind shear resulted in airspeed deviations of no greater than 10 IAS. The resulting approach and landing were uneventful.I would have expected 'Too Low Flaps' for this condition. I am not sure why we got 'Too Low Terrain'. Either warning would have given the same result; but we would have had more clarity on our issue with the more appropriate warning.
Air carrier Captain reported experiencing gusty wind conditions which necessitated a go-around followed by a successful second approach and landing.