This idiom describes acting or making decisions spontaneously, without a clear plan or preparation, relying on instinct or improvisation. It suggests navigating a situation with minimal guidance, akin to piloting a plane without instruments, and is used in contexts of work, performance, or emergencies to highlight adaptability or recklessness. The phrase carries a dynamic, slightly daring tone, reflecting admiration for quick thinking or critique of unpreparedness, and underscores the cultural tension between planning and spontaneity in high-pressure scenarios.

The phrase originated in early 20th-century American aviation, where pilots, especially during the 1920s barnstorming era, sometimes flew without reliable instruments, relying on their ‘seat’ (sensing the plane’s movements). An early use appears in a 1932 *New York Times* article about a pilot ‘flying by the seat of his pants’ in fog. The idiom gained traction during World War II, reflecting the daring of aviators, as seen in Ernie Pyle’s war correspondence. Its metaphorical use grew in the mid-20th century, particularly in business and creative fields, and was popularized in American English through films and literature, spreading to British English by the 1960s. The phrase’s adventurous imagery ensured its enduring appeal, especially in contexts of risk and innovation.