What was found
(AIRCRAFT NOT GROUNDED) DURING TAKE OFF, AFT FA'S 2 & 4 HAD A DIRTY SOCK ODOR. LASTED ABOUT 3 MIN DURING + AFTER TAKE OFF. INTENSITY OF ODOR WAS MODERATE & LIGHT PER FA'S. NO VISIBLE SMOKE EITHER, AIR SOURCE USED AT GATE WAS GROUND AIR & THEN APU AIR, ENG START APU. APU BLEED OFF DURING T/O. XBLEED OFF, PACK 1 & 2 ON, BLEED 1 & 2 ON, WEATHER WAS 28C WINDS 027/07 & DRY / PERFORMED TC 001 AND LEVEL A DECON IAW AMM 21-00-00-815-802-A. NO ODOR REPRODUCED.