Apple has announced that Bob Mansfield, Apple’s senior vice president of Hardware Engineering, will retire and the role will be transitioned to Dan Riccio, Apple’s vice president of iPad Hardware Engineering, over several months. The entire hardware engineering team will continue to report to Mansfield until his departure.

“Bob has been an instrumental part of our executive team, leading the hardware engineering organization and overseeing the team that has delivered dozens of breakthrough products over the years,” says Apple CEO Tim Cook. “We are very sad to have him leave and hope he enjoys every day of his retirement. Dan has been one of Bob’s key lieutenants for a very long time and is very well respected within Apple and by the industry. Our hardware engineering team is the best engineering team on earth and will not miss a beat during the transition.”

As senior vice president of Hardware Engineering, Mansfield has led Mac hardware engineering since 2005, iPhone and iPod hardware engineering since 2010, and iPad hardware engineering since its inception. Mansfield joined Apple in 1999 when Apple acquired Raycer Graphics, where he was vice president of Engineering. Mansfield earned a BSEE degree from the University of Texas at Austin in 1982.

Riccio currently serves as vice president of iPad Hardware Engineering and has been instrumental in all of Apple’s iPad products since the first generation iPad. Riccio joined Apple in 1998 as vice president of Product Design and has been a key contributor to most of Apple’s hardware over his career. He earned a bachelor’s degree in Mechanical Engineering from the University of Massachusetts Amherst in 1986.

Also, Betsy Rafael — Apple vice president, corporate controller and principal accounting officer — will retire on Oct. 19, per an SEC filing as noted by “The Mac Observer” (http://www.macobserver.com). No replacement has been named.

Before Apple, Rafael worked for Cisco from 2003 to 2006 as the principal accounting officer, and from 2006 to 2007 as vice president and corporate controller. Prior to that, she worked Aspect Communications, Escalate Corporation, Silicon Graphics, and Sun.