Abstract: A projectile is propelled from a location in air, through an air/water interface, and toward a submerged underwater object. The projectile includes a forward end that forms a cavitation void around the projectile in water, avoiding water drag on the remainder of the projectile. The projectile further includes an outwardly flared or finned rearward end that aerodynamically stabilizes the projectile in air and flare stabilizes it in water, in each case against yaw.

Abstract: A football place-kicking practice holder has a base adapted to rest on a playing surface and support a football at its lower end when in a teed up position, an elongated rigid support member attached to the base and mounted in an upright position on the base such that it is spaced from one side of the football, and an elongated rigid arm being pivotally mounted to the support member for movement through an arcuate path downwardly toward, and upwardly away from, the football and in a direction extending generally transverse to the general direction of flight of the football when kicked from the teed up position. An outer end of the arm has a threaded section which is located between the support member and the football when the arm has been moved downwardly toward the football and a flexible hollow finger inserted on the outer end of the arm is disposed into contact with an upper end of the football for maintaining it in the teed up position.