How are aircraft saving jet fuel with gradual descents?

A white Mesa regional jet with a blue tail flying through blue sky and clouds as it comes in for a landing. The FAA's new rules allow planes to descend more efficiently.

The Federal Aviation Administration last year established optimized profile descents at 42 airports last year with the goal of saving millions of gallons of fuel and reducing CO2 and other emissions. Another benefit is less noise.

Let’s cut through the technical language. Optimized Profile Descents (OPD) are new flight techniques that allow airplanes to descend from cruising altitude to the runway in a smooth, continuous slope with engines set at near idle. In other words, pilots flying into...

https://www.freightwaves.com/news/how-are-aircraft-saving-jet-fuel-with-gradual-descents