<P> Versions of the 777 have been acquired by government and private customers . The main purpose has been for VIP transport, including as an air transport for heads of state, although the aircraft has also been proposed for other military applications . </P> <Ul> <Li> 777 Business Jet (777 VIP)--the Boeing Business Jet version of the 777 that is sold to corporate customers . Boeing has received orders for 777 VIP aircraft based on the 777 - 200LR and 777 - 300ER passenger models . The aircraft are fitted with private jet cabins by third party contractors, and completion may take 3 years . </Li> <Li> 777 Tanker (KC - 777)--the KC - 777 is a proposed tanker version of the 777 . In September 2006, Boeing announced that it would produce the KC - 777 if the United States Air Force (USAF) required a larger tanker than the KC - 767, able to transport more cargo or personnel . In April 2007, Boeing offered its 767 - based KC - 767 Advanced Tanker instead of the KC - 777 to replace the smaller Boeing KC - 135 Stratotanker under the USAF's KC - X program . Boeing officials have described the KC - 777 as suitable for the related KC - Z program to replace the wide - body McDonnell Douglas KC - 10 Extender . </Li> <Li> In 2014, the Japanese government chose to procure two 777 - 300ERs to serve as the official air transport for the Emperor of Japan and Prime Minister of Japan . The aircraft, to be operated by the Japan Air Self - Defense Force under the callsign Japanese Air Force One, are scheduled to enter service in 2019 and replace two 747 - 400s . Besides VIP transport, the 777s are also intended for use in emergency relief missions . </Li> <Li> 777s have served as official government transports for nations including Gabon (VIP - configured 777 - 200ER), Turkmenistan (VIP - configured 777 - 200LR), and the United Arab Emirates (VIP - configured 777 - 200ER and 777 - 300ER operated by Abu Dhabi Amiri Flight). Prior to returning to power as Prime Minister of Lebanon, Rafic Hariri acquired a 777 - 200ER as an official transport . </Li> <Li> In 2014, the USAF examined the possibility of adopting modified 777 - 300ERs or 777 - 9Xs to replace the Boeing 747 - 200 aircraft used as Air Force One . Although the USAF had preferred a four engine aircraft, this was mainly due to precedent (the existing aircraft were purchased when the 767 was just beginning to prove itself with ETOPS; decades later, the 777 and other twin jets established a comparable level of performance as quad - jet aircraft). Ultimately, the air force decided against the 777, and selected instead the Boeing 747 - 8 to become the next presidential aircraft . </Li> </Ul> <Li> 777 Business Jet (777 VIP)--the Boeing Business Jet version of the 777 that is sold to corporate customers . Boeing has received orders for 777 VIP aircraft based on the 777 - 200LR and 777 - 300ER passenger models . The aircraft are fitted with private jet cabins by third party contractors, and completion may take 3 years . </Li> <Li> 777 Tanker (KC - 777)--the KC - 777 is a proposed tanker version of the 777 . In September 2006, Boeing announced that it would produce the KC - 777 if the United States Air Force (USAF) required a larger tanker than the KC - 767, able to transport more cargo or personnel . In April 2007, Boeing offered its 767 - based KC - 767 Advanced Tanker instead of the KC - 777 to replace the smaller Boeing KC - 135 Stratotanker under the USAF's KC - X program . Boeing officials have described the KC - 777 as suitable for the related KC - Z program to replace the wide - body McDonnell Douglas KC - 10 Extender . </Li>

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