How Reliable Is Your Flight?

The risk score (1-100) combines four factors from historical DOT data:

• ·Delay probability (40%) — how often flights on this route arrive late (15+ minutes)
• ·Delay severity (20%) — when flights are late, how late they typically are
• ·Cancellation rate (20%) — percentage of flights cancelled outright
• ·Seasonal volatility (20%) — how much reliability swings between best and worst months

Scores under 30 are Low Risk, 31-60 are Moderate, 61-80 are High, and 81+ are Very High.

Routes through weather-prone hubs consistently rank worst for delays:

• •EWR (Newark) — congested airspace, weather exposure, and cascading delays from the NYC metro area
• •SFO (San Francisco) — marine fog forces single-runway operations, cutting capacity in half
• •ORD (Chicago O'Hare) — winter storms and thunderstorms both impact this major hub
• •LGA (LaGuardia) — small airport with high volume and shared NYC airspace

1. Book the first departure — aircraft haven't accumulated delays from earlier legs yet
2. Check the seasonal pattern — the same route can be 20+ percentage points more reliable in fall vs. winter
3. Compare airlines — carrier matters. On the same route, one airline can be 10+ points more on-time
4. Build in buffer time — if connecting, allow extra time on routes with high delay probability
5. Know your rights — if delayed 3+ hours on a domestic flight, you're entitled to a full refund under DOT rules