SWISS airline pilot Guido Keel was assaulted following a dispute about whether a baby carriage could be transported in the plane's cabin, rather than in the hold, a spokeswoman for the airline told CNN.
The alleged incident took place after the flight had landed.
Henrietta Mitaiare, 23, and Mary Roberts, 53, both from London, are accused of scratching and kicking the pilot after the flight landed at London's Heathrow Airport on May 2 last year, the UK's PA Media agency reports.
The women deny charges of failing to obey the lawful commands of the aircraft's captain and assault by beating on board.
Prosecutors say the pilot also had a bite mark on his upper arm.
Uxbridge Magistrates' Court heard that the pair were traveling with Mitaiare's young daughter and had asked flight attendant Ali Chkerdaa to store the stroller in the cabin before takeoff.
Chkerdaa told the court that he refused and an argument broke out between Mitaiare and two airport workers, but the flight took off for London.
Upon landing, Mitaiare approached Chkerdaa and asked to note down the airport workers' names in order to make a complaint, according to prosecutor Arlene De Silva.
After some back and forth, Keel came out of the cabin and a struggle ensued, during which the captain suffered scratches on his face and arm and a bite on his arm, De Silva said.
Chkerdaa told the court that Mitaiare objected to Keel getting involved.
"She said something (to Capt Keel) like, 'Don't meddle with it, you have nothing to do with it,'" he said. "She said Swiss people are racist, because she was a black woman traveling with a child."
Keel asked her to step outside and stop the argument, but Mitaiare reacted badly when he touched her, Chkerdaa said.
"She said, 'Don't touch me'," he added. "The moment he touched her she went all crazy."
PA reported that the court was shown footage in which Mitaiare is heard saying: "Why did you put your hands on me? Why did you hit a woman? Do you think you have the power?"
Keel is heard replying: "I have the power."
According to De Silva, Mitaiare grabbed Keel's hand and pushed him into the cockpit, where they struggled before Roberts allegedly went in and kicked him.
Following the altercation police removed the women from the aircraft and arrested them.
Corker Binning, the law firm representing Mitaiare, and IBB Solicitors, representing Roberts, were not immediately available to comment.
Keel received medical treatment after the incident and has since returned to work, SWISS told CNN.