according to a 2016 report by the US Government Accountability Office, the estimated cost per flight hour for the F22 was around $35,000. This includes fuel, maintenance, and other operational costs.
刚问过ChatGPT,只要加入氢气和空气混合，可燃浓度是4%-74%。我估计氢氦混合气体，因为没有氧气，其浓度会高很多，所以保守来说，兑入10%的氢气，绝对是保险的，这一下成本降低10%，呵呵。
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ChatGPT的答案：In general, however, hydrogen-air mixtures with a concentration of 4% to 74% are flammable, meaning that they can ignite under certain conditions.
