Narrative:

A strong line of convective activity was north of the area; which was moving south southeast. On arrival in the area we were vectored to the rwyxxl approach. On final at approximately 1;200 ft we received a wind check of 0x0 gusting to over 20 KTS so we executed a go around without descending below 1;000 ft and requested an approach to runway yyr. Approach said yy was not available but could give us zzl which we accepted. Thus far we had only encountered light chop so we considered a crosswind landing acceptable. As we were vectored to the ILS zzl final at 2;000 ft the field was still visible and we were still VMC but we encountered significant windshear and turbulence. I noted a sudden 30 KT speed increase; 200 ft climb and the autothrottles retarded all the way to idle at which point we agreed to abandon the approach without ever leaving vectoring altitude. The captain called for go around power and asked for 3;000 ft so I hit the go around switches as instructed. Approach told us to maintain 2;000 ft and since go around power in level flight would have given us rapid acceleration; I immediately disconnected the autothrottles to control the acceleration and disconnected the autopilot to avoid climbing away from the assigned altitude. We received an amber windshear annunciation and were experiencing moderate turbulence with airspeed transients of plus or minus 30 to 40 KTS and vsi transients of plus or minus 4-500 FPM. The captain argued for a climb to 3;000 ft but ATC was not cooperative. I heard the captain say 'declare an emergency' and he then set 3;000 ft in the MCP altitude window and directed me to turn to the south. During the climb he again demanded go around power which I selected as instructed. Since we were quickly approaching 3;000 ft and were accelerating rapidly I again disconnected the autothrottles and attempted to level while maintaining airspeed control. Since the turbulence continued with both horizontal and vertical shears both altitude and airspeed control were difficult and I was not able to arrest the climb until approximately 3;300 ft. I promptly returned the aircraft to 3;000 ft; completed retracting the flaps and engaged the autopilot and autothrottles as demanded by the captain.it was reported to me that a flap speed was exceeded but due to the conditions and transients in speed I did not realize it had occurred. We then requested our alternate and landed uneventfully. There were no injuries due to the turbulence.

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Original NASA ASRS Text

Title: After experiencing turbulence; windshear; a temporary altitude deviation and a flap overspeed while attempting two approaches and subsequent go arounds; the flight crew of a B767 diverted to their alternate.

Narrative: A strong line of convective activity was north of the area; which was moving south southeast. On arrival in the area we were vectored to the RWYXXL approach. On final at approximately 1;200 FT we received a wind check of 0X0 gusting to over 20 KTS so we executed a go around without descending below 1;000 FT and requested an approach to Runway YYR. Approach said YY was not available but could give us ZZL which we accepted. Thus far we had only encountered light chop so we considered a crosswind landing acceptable. As we were vectored to the ILS ZZL final at 2;000 FT the field was still visible and we were still VMC but we encountered significant windshear and turbulence. I noted a sudden 30 KT speed increase; 200 FT climb and the autothrottles retarded all the way to idle at which point we agreed to abandon the approach without ever leaving vectoring altitude. The Captain called for go around power and asked for 3;000 FT so I hit the go around switches as instructed. Approach told us to maintain 2;000 FT and since go around power in level flight would have given us rapid acceleration; I immediately disconnected the autothrottles to control the acceleration and disconnected the autopilot to avoid climbing away from the assigned altitude. We received an amber windshear annunciation and were experiencing moderate turbulence with airspeed transients of plus or minus 30 to 40 KTS and VSI transients of plus or minus 4-500 FPM. The Captain argued for a climb to 3;000 FT but ATC was not cooperative. I heard the Captain say 'declare an emergency' and he then set 3;000 FT in the MCP altitude window and directed me to turn to the south. During the climb he again demanded go around power which I selected as instructed. Since we were quickly approaching 3;000 FT and were accelerating rapidly I again disconnected the autothrottles and attempted to level while maintaining airspeed control. Since the turbulence continued with both horizontal and vertical shears both altitude and airspeed control were difficult and I was not able to arrest the climb until approximately 3;300 FT. I promptly returned the aircraft to 3;000 FT; completed retracting the flaps and engaged the autopilot and autothrottles as demanded by the Captain.It was reported to me that a flap speed was exceeded but due to the conditions and transients in speed I did not realize it had occurred. We then requested our alternate and landed uneventfully. There were no injuries due to the turbulence.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.