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Cultural and career issues in the U.S. Air Force have been cited as one of the reasons for the shortfall in needed UAV operators. In spite of an urgent need for UAVs or drones to provide round the clock coverage for American troops during the Iraq War, the USAF did not establish a new career field for piloting them until the last year of that war and in 2014 changed its RPA training syllabus again, in the face of large aircraft losses in training, and in response to a GAO report critical of handling of drone programs. Paul Scharre has reported that the cultural divide between the USAF and US Army has kept both services from adopting each other's drone handing innovations.

Why did the USAF change its training methods on UAVs in 2014?
Answer: large aircraft losses in training
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The incentive to use 100% renewable energy, for electricity, transport, or even total primary energy supply globally, has been motivated by global warming and other ecological as well as economic concerns. The Intergovernmental Panel on Climate Change has said that there are few fundamental technological limits to integrating a portfolio of renewable energy technologies to meet most of total global energy demand. In reviewing 164 recent scenarios of future renewable energy growth, the report noted that the majority expected renewable sources to supply more than 17% of total energy by 2030, and 27% by 2050; the highest forecast projected 43% supplied by renewables by 2030 and 77% by 2050. Renewable energy use has grown much faster than even advocates anticipated. At the national level, at least 30 nations around the world already have renewable energy contributing more than 20% of energy supply. Also, Professors S. Pacala and Robert H. Socolow have developed a series of "stabilization wedges" that can allow us to maintain our quality of life while avoiding catastrophic climate change, and "renewable energy sources," in aggregate, constitute the largest number of their "wedges."

How many nations already have renewable energy contributing to more than 20 percent of energy supply?
Answer: at least 30 nations
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A further limitation of the gramophone record is that fidelity steadily declines as playback progresses; there is more vinyl per second available for fine reproduction of high frequencies at the large-diameter beginning of the groove than exist at the smaller-diameters close to the end of the side. At the start of a groove on an LP there are 510 mm of vinyl per second traveling past the stylus while the ending of the groove gives 200210 mm of vinyl per second less than half the linear resolution. Distortion towards the end of the side is likely to become more apparent as record wear increases.*

What is a drawback of using gramophones?
Answer:
fidelity steadily declines as playback progresses