MJN Air is a fictional air ambulance service featured in the popular animated television series, Arthur. The service is operated by Buster Baxter, one of the main characters, who takes on the role of a pilot. MJN Air provides emergency medical transport, showcasing the importance of quick response in critical situations. The air ambulance is depicted as a small, colorful aircraft that can reach remote areas quickly. The episodes often highlight the teamwork and problem-solving skills of the characters as they navigate various challenges while ensuring patients receive timely care.