The Propeller Hammer (プロペラハンマー,Puroperahanmā?) is a technique used by Amy Rose. It first appeared in Sonic Heroes. When performing this move, Amy spins her Piko Piko Hammer to gain temporarily flight.
When using the Propeller Hammer, Amy pulls out her Piko Piko Hammer and begins swirling around with it in a manner similar to a propeller. This creates an updraft that allows her to momentarily sustain flight through the air for a short time.
The Propeller Hammer first appeared in Sonic Heroes where it is a Speed Formation maneuver used by Amy on Team Rose. In this game, it allows the player to move slowly through mid-air, making it possible to cross gaps and bottomless pits, though it can only be sustained for a few seconds before Amy will drop down. When using the Propeller Hammer, Amy leaves a trail of pink hearts.
To perform the Propeller Hammer in gameplay, Team Rose must be in Speed Formation with Amy as the leader. The player must then hold down // during a jump to use the Propeller Hammer. The traveling distance of the Propeller Hammer can be increased by performing a sequence of moves; first use the Propeller Hammer, then use the Tornado Hammer before running out of flight, then resume the use of the Propeller Hammer, etc.
The Propeller Hammer made a cameo appearance in the console/PC version of Sonic Generations. In this game, it appeared in the Amy: Topsy TurvyChallenge Act where Amy uses it to race against Classic Sonic to the Goal Plate. Here, it appears that Amy has perfected this move as she can use it to fly better through the air and change her height at will. When using it in this game, Amy resembles a small pink tornado. If the player contacts with her while utilizing the move, she will get knocked and temporary immobilized.