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On April 13 , 2019 , the Stratolaunch aircraft made its maiden flight , reaching and 165 " kn ( 305 " km/h ) in a 2 h 29 min flight .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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