85504
One of this batch was changed during production to so that it could be fitted with two Rolls-Royce Nene turbojet engines , with its first flight on 6 April 1948 .
 Rolls-Royce Nene
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:
 Rolls-Royce Nene