after bottom center

after bottom center

after bottom centerclick for a larger image
As soon as after bottom center point is reached, the piston changes its direction of movement from downward to upward.
The position of a piston in the cylinder of a reciprocating engine after the crankshaft, turning in its normal direction of rotation, has caused the piston to pass the bottom of its stroke and start back up.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved