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This article is a classic example of why you should always take everything from the media with a grain of salt. Nobody is going to shut off engines and glide into the airport, that's just stupid. We're also not going to do the final approach at idle, you couldn't maintain the proper glideslope that way. What an optimum profile descent does is attempt to time the initial descent out of altitude where you can do an idle descent until you start configuring for the final approach (putting the flaps out and gear down). The point to start your descent can be approximated in most airliners by multiplying the altitude times 3, so if you're at 30,000' you'd start your initial descent at 90 miles. That changes depending upon winds so the flight management system (FMS) can calculate the point precisely, but the 3:1 rule will get you close.

At most airports the airspace is too busy to allow someone to do an uninterrupted descent out of altitude, they'll stop you to deconflict traffic so you end up doing a descent with multiple step downs. That's not very fuel efficient so they're trying to change routings and procedures to avoid all the level offs on the descent. That's a good thing. The approach is not going to be flown at idle so everyone panicking about spool up time can breathe. When configured for landing with flaps out and gear down there's a lot more drag on the airplane which requires the final approach to be flown using a mid range power setting. The typical glideslope is 3 degrees which equates to 300' of altitude loss per mile and a rate of descent of about 700 feet per minute in a typical airliner. If you pulled the power to idle while configured for landing you'd dramatically increase your rate of descent, you have to fly the final approach with a mid range power setting until you flare and reduce the power to idle before touchdown.

I'm an airline pilot and that's how it works. There's nothing remotely dangerous about an optimum profile descent, it's just timing the traffic coming into an airport so you're not constantly having to make adjustments for other traffic. Think of it as if a city timed all the stop lights on a major road so they continually changed green as you approached the next one, you'd never have to stop so you'd save gas instead of wasting time sitting at red lights.

That article has a lot of really dumb errors in it that obviously are causing panic over this for no reason.

Airline pilot Unions should immediately put out press releases that this kind of thing is absolute nonsense.

This article is an example of the DOT trying to be green and trying to show the press how they are doing something about “climate change.”

Airline pilots have ALWAYS worked to be efficient because we know the fuel we save is ours to use in unforeseen contingencies. No one wastes fuel, because we know fuel is our life when we are in the air - not because we are “trying the save the planet.”