Revealing mistake: When Ace accelerates away from the Nazi troops, he is holding a gun in his right hand. He should not have been able to accelerate away as the throttle handle is on the right. (00:03:45)
Revealing mistake: At The End of the episode when Ace takes off in the ejector seat, a black cable can be seen lifting the chair up. (00:27:55)
Answer: The cello is a large four-stringed instrument, which, when it is played, stands vertically on the floor between the player's legs (assuming they are seated). If it is to grow as large as the other instuments mentioned will, it would require a rather unseemly lack of femininity to be able to encompass it with the legs.
Rooster of Doom