The character of Howard Roark in Ayn Rand's 'The Fountainhead' is sometimes thought to draw some inspiration from Howard Hughes. They share a determination and a visionary spirit in their respective fields.
In the world of cinema, the character of Daniel Plainview in 'There Will Be Blood' has been seen by some as having elements inspired by Howard Hughes. Both were driven and had complex personalities in their pursuits.
One fictional character based on Howard Hughes is Tony Stark from the Marvel universe. His personality and business acumen share some similarities with Hughes.