The airline sector is experiencing a significant pre-market rally, with the JETS ETF up over 2%, primarily driven by a sharp drop in crude oil prices. A de-escalation in geopolitical tensions with Iran has led to a more than 5% fall in Brent crude. This is a significant positive for airlines as fuel is one of their largest operating expenses. News of a major aircraft delivery by Boeing and positive analyst commentary on specific carriers like Delta are also contributing to the positive sentiment, but the drop in oil is the primary, sector-wide catalyst.