Airlines are using long-readied contingency plans but bottlenecks have formed that no amount of planning can fix

• Middle East crisis – live updates

A war engulfing the Middle East has cleared the region’s skies, forcing airlines to make drastic rerouting plans and leaving a massive void in usually busy global airspace.

With Israel and the US bombing Iran day after day – and Tehran responding with waves of missiles and drones attacks – airlines have been forced to divert their passenger jets away from the Gulf or risk a catastrophic accident.