B757 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Type 7682
Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
General Maintenance Action
Aircraft
We were cleared for takeoff. I advanced the throttles per normal procedure. Once we lifted off; we could smell a slight odor. As we climbed higher; the odor got stronger. It was the worst between 3;500 to 12;000 feet. This odor would be characterized as 'musty; smelly gym socks'. As we climbed higher (through 15;000 feet MSL); the odor went away. I checked with the flight attendants. They said they could smell it too. I considered this a fume event. There was a previous write up for the same occurrence. The last crew stated it happened on descent. We also experienced the same fumes on descent; but not to the extent of departure.
B757 Captain reported noticing a 'dirty socks' odor after takeoff.