Amazon has won approval from U.S. federal regulators to test the latest version of its delivery drone outdoors , less than a month after the e-commerce powerhouse blasted regulators for being slow to approve commercial drone testing . The Federal Aviation Administration had earlier given the green light to an Amazon prototype drone in March , but the company told U.S. lawmakers less than a week later that the prototype had already become obsolete while it waited more than six months for the agency 's permission . The FAA granted Amazon 's request to test its new delivery drones in a letter dated Wednesday , posted on the agency 's website . Scroll down for video . The company must supply monthly data to the regulators , and conduct flights at 400 feet ( 120 metres ) orbelow and in 'visual meteorological conditions , ' Amazon is developing aerial vehicles as part of Amazon Prime Air . The aircraft can travel at more than 50mph and carry loads of up to 5 pounds . About 86 percent of Amazon 's deliveries are 5 pounds or less , the company said . 'We believe customers will love it , and we are committed to making Prime Air available to customers worldwide as soon as we are permitted to do so , ' Amazon has said . Amazon must keep flights at an altitude of no more than 400 feet ( 120 meters ) and no faster than 100 miles per hour ( 160 km per hour ) , according to the letter . Seattle-based Amazon.com has been pursuing its goal of sending packages to customers by air , using small , self-piloted aircraft , even as it faces public concern about safety and privacy . The company wants to use drones to deliver packages to its customers over distances of 10 miles ( 16 km ) or more , which would require drones to travel autonomously while equipped with technology to avoid collisions with other aircraft . In February , the FAA proposed long-awaited rules to try to set U.S. guidelines for drones , addressing growing interest from both individual and corporations in using unmanned aerial vehicles . Amazon did not immediately respond to requests for comment . Previously the firm blasted federal regulators for being slow to . approve commercial drone testing - and warned the United States is . falling behind other countries in the potentially lucrative area . of unmanned aviation technology . Less than a week after the Federal Aviation Administration . gave Amazon.com the green light to test a delivery drone . outdoors , the company told U.S. lawmakers that the prototype . drone had already become obsolete while the company waited more . than six months for the agency 's permission . 'Nowhere outside of the United States have we been required . to wait more than one or two months to begin testing , ' Misener . said in written testimony submitted to the Senate Subcommittee . on Aviation Operations , Safety and Security . Misener said Amazon had applied on Friday for permission to . test a more advanced drone system and now hopes for quicker . approval . The Amazon.com case illustrates the frustrations of many . companies and industry lobbyists , who say the U.S. regulatory . process is not keeping up with rapidly developing drone . technology that could generate new revenues and cost savings for . a range of industries . Misener , who was scheduled to join a witness panel at the . subcommittee hearing , said European and other international . authorities have more 'reasonable ' approaches that recognize the . potential economic benefits of commercial drone operations . 'This low level of government attention and slow pace are . inadequate , especially compared to the regulatory efforts in . other countries , ' Misener said . 'The ( FAA ) already has adequate statutory authority . 'What . the FAA needs is impetus , lest the United States fall further . behind , ' he added . The FAA recently proposed rules that would lift the current . ban on most commercial drone flights , but several restrictions . attached would make package delivery and other business . applications unfeasible . Among other constraints , the proposed rules would limit . commercial drones to an altitude of 500 feet ( 150 metres ) , allow . flights only during daytime and require operators to keep the . aircraft in sight at all times . The agency does not expect to finalize the rules until late . 2016 or early 2017 , according to government officials .
FAA gave Amazon green light to test latest version of its drone . Had previously taken so long to approve trial design was obsolete . Amazon has been testing its drones in the UK .