The traditional way to make a driver more forgiving is to make its face larger and the head bigger from front to back. However, that tends to make the club less aerodynamic, so the head loses speed and distance is compromised.
To address this issue, Callaway partnered with aerospace company Boeing in the development of a crown that is the key feature in the new XR16 and XR16 Pro drivers.
Basically, Callaway placed panels on the crown of the XR16 and XR16 Pro to make the air stick to the driver more effectively instead of swirling away and creating drag.
“One way to control the air is to introduce a flow-tripping feature,” said Alan Hocknell, Callaway’s senior vice president of research and development. “You can see the new Speed Step is above the crown surface, but not by very much, because the actual layer of air that we are most concerned about is only really of importance to us very, very close to the surface. The feature doesn’t need to be very tall at all. But it does need to be very close (to the seam where the face and crown meet), and it does need to have a sharpness to that edge.”
Hocknell also said there are aerodynamic disadvantages to a panel in the center of the head, so Callaway left a gap in the middle of the crown.
Callaway gave the XR16 and XR16 Pro drivers an updated version of the R*MOTO face. It is 9 grams lighter and 20 percent thinner than the face in last season’s XR drivers. While a ribbed design in the front of the sole gives strength to the hitting area, the weight saved in the face has been re-distributed low in the back of the club, which lowered the center of gravity and increased moment of inertia and forgiveness.
The 460cc XR16 is available in 9-, 10.5- and 13.5-degree models. The 450cc XR16 Pro is available in 9- and 10.5-degree heads with a deeper face than the standard model and a more-neutral CG that produces slightly less spin and has a slightly lower initial launch angle.
The XR16 comes standard with a Fujikura Speeder Evolution 565 shaft for $349.99. The XR16 Pro comes with a Fujikura Evolution II TS 665 shaft for $399.99. Both clubs will be in stores Jan. 29 and can be purchased with several other premium shafts through custom order without additional charges.