Assertion: balsa's quality | /r/HasProperty | certified
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text: These qualities, and the turbine's high-thrust output, makes owning and operating a turbine-powered aircraft prohibitively expensive for most hobbyists, as well as many nations' national aeromodeling clubs (as with the USA's AMA) requiring their users to be certified to know how to safely and properly operate the engines they intend to use for such a model.