Singapore appears to have quietly boosted the size of its F-15SG fleet from 24 aircraft to 40, according to Boeing financial statements, aircraft registration filings, and US congressional reports.
Singapore originally bought 12 F-15SGs - with an option for eight more - under a contract signed in December 2005. In October 2007 the city-state modified this option by buying 12 more to give it a total of 24.
These aircraft have all been confirmed as delivered and have US-type serial numbers running from 05-0001 to 05-0024. Several remain in the United States with the Republic of Singapore Air Force's (RSAF's) 428th Fighter Squadron at Mountain Home Air Force Base (AFB) in southwestern Idaho, while the remainder are active in Singapore with 149 Squadron.
Aircraft operating in Singapore use four-digit serial numbers in the 83xx sequence, starting at 8301, although these do not run consecutively.
