This is after the Kenya Airways Board accepted the resignation of Titus Naikuni as the Director and CEO of the national carrier with effect from October 31, 2014.
Ngunze was initially set to take over from Titus Naikuni in December.
Naikuni is leaving the airline after 11 years of service.
He is headed to chair the Rift Valley Railways'(RVR) Board of Directors with effect from November this year.
Naikuni will head a board that has been reconstituted following recent shareholder restructuring at the regional rail operator.
His appointment comes at a time when RVR is at the midpoint of a Sh25 billion capital investment and turnaround programme that began in January 2012 to revitalise the rail firm that had been ailing from years of neglect and underfunding.
Naikuni joined the Kenya Airways as group CEO in 2003 and spearheaded growth in one of the most noteworthy African airline.
Prior to joining the national carrier Naikuni was Group Managing Director of the Magadi Soda Company.
In 1999 he was appointed Permanent Secretary in the Ministry of Information, Transport and Communication as part of a team of experts engaged by government to drive economic reform.
His extensive boardroom experience spans the energy, mining, real estate, banking, film, manufacturing and ICT sectors.