最令航天业担忧的是钇供应紧张。钇是高温防护涂层中的关键成分，可防止发动机和涡轮在高温下“熔化”，一旦无法定期施涂相关涂层，发动机便无法正常服役。
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Scott spent 20 years at Tottenham until leaving two years ago after a clash with the then manager, Ange Postecoglou, who was in charge of Forest for eight matches this season.