I roto i te 1963, i timata te United States Air Force he raupapa o ngā kaupapa ako i runga i te waka rererangi transport rautaki rawa nui. Ahakoa i te C-141 Starlifter i whakaurua, whakapono nga apiha e hiahiatia ana he nui nui atu, me te ake pūmanawa rererangi, rawa ki te kawe i te utanga e kore e uru i roto i tetahi waka rererangi o nāianei. arahina enei rangahau ki ngā whakaritenga tuatahi mo te CX-Heavy Logistics Pūnaha (CX-HLS) i roto i Maehe 1964 mo te waka rererangi ki te kawenga o 180,000 pauna (81,600 kg) me te tere o Mach 0.75 (500 ranei 800 km / h), me te whānuitanga unrefueled o 5,000 maero moana (9,300 km) ki te utanga o 115,000 pauna (52,200 kg). i te utanga whai hua i ki kia 17 waewae m (5.18 m) whanui e 13.5 waewae teitei (30 m) me 100 waewae roa ki te tatau i roto i te mua, me te hiahia ki te pupuri i te waka rererangi i roto i te taha o mua, me te hoki. i roto i nga tono katoa i
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