74138
Primary operators include Regional Express with 52 aircraft , Silver Airways with 21 , Loganair with 16 , PenAir with 13 , SprintAir with 12 , and others with fewer aircraft of the type .
 Regional Express, Silver Airways, Loganair, PenAir, SprintAir
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 Regional Express, Silver Airways, Loganair, PenAir, SprintAir