The first effort of the game came on four minutes from new Hammers arrival Joao Mario, whose first-time connection from Chicharito's knock-down sent the ball flying wide of target.
Hernandez then nearly turned goalscorer when Timothy Fosu-Mensah nudged the ball into the Mexico forward's path, only for former West Ham man James Tomkins to make a last-ditch tackle.
Despite the Hammers' best efforts, their spurned opportunities allowed Palace to take the lead, Townsend charging deep into the opposition half and lofting the ball to the middle of the penalty area where the unmarked Benteke nodded beyond Adrian.
The visitors suffered an injury setback five minutes before half time, however, when Bakary Sako limped off following a heavy challenge by Pablo Zabaleta.
Three minutes later the Hammers were level as Tomkins made a late challenge on Hernandez in the area, prompting the referee to blow for a penalty, which Noble dispatched into the bottom-left corner for his 50th Premier League goal.
Wayne Hennessey kept Palace in the game with a smart save from Hernandez's bullet header five minutes after the restart, while Declan Rice blasted over from the edge of the box on 64 minutes.
The second half was a tighter affair for the most part and, save for Aaron Cresswell's header on 75 minutes which went over, there was little to separate the two sides on the pitch as the final whistle indicated a share of the spoils.
WEST HAM (5-4-1): Adrian; Zabaleta, Collins, Ogbonna, Cresswell, Rice; Byram, Noble, Kouyate (Oxford 86'), Mario; Hernandez