Older Boeing jets are now in hot demand because of the 737 Max grounding

As the worldwide grounding of the Boeing 737 Max enters its sixth month, airlines are turning to older jets to help meet growing demand, prompting a surge in rental rates.

“Used 800s are like a gold dust at the moment,” said Phil Seymour, CEO of London-based aerospace consulting firm IBA, referring to Boeing 737-800s, an older model of the plane. He estimates lease rates for 24 months or less, for some older 737 planes have gone up 40% to about $300,000 since regulators grounded the planes in March after two fatal crashes within five months of one another. Together the two disasters claimed 346 lives — everyone on board the two planes — and regulators have not said when they will allow the planes to fly again.

Crash investigators have implicated a piece of flight-control software that repeatedly pushed the nose of the planes down in both the Lion Air and Ethiopian Airlines crashes. Boeing is testing a software fix for the planes and expects regulators to allow the jets to return to service early in the fourth quarter, but warned that the date could be pushed back further.