Are Boeing 747 planes soon to be no longer for sale? The iconic Boeing 747 planes may be coming to an end, as newer, more efficient planes are taking over the market for airlines.

Most airlines are no longer looking for Boeing 747 planes, which run on four engines. Airlines prefer newer, two-engine jets that fly the same distance while burning less fuel, ABC News reports via AP.

"We had four engines when jet engine technology wasn't advanced," Delta Air Lines Inc. CEO Richard Anderson said at a recent conference. "Now jet engines are amazing, amazing machines and you only need two of them."

According to AP, Boeing has cut its production target twice in six months. Just 18 Boeing 747 planes will be produced in each of the next two years.

Counting cancellations, Boeing hasn't sold a single 747 this year. Some brand-new 747s go into storage as soon as they leave the plant, AP reports.

Boeing says it's committed to the 747, and sees a market for it in regions like Asia. The iconic plane may not be gone forever just yet, but it seems as though the end is nigh.

Another problem with the Boeing 747s? All those seats.

According to AP, a 747 can seat from 380 to 560 people, depending on how an airline sets it up. An airline that can't fill all the seats has to spread the cost of 63,000 gallons of jet fuel - roughly $200,000 - among fewer passengers.

And there aren't enough passengers who want to fly each day on most routes to justify several jumbo jet flights. And business travelers want more than one flight to choose from. So airlines fly smaller planes several times a day instead, AP reports.

"No one wants the extra capacity" that comes with jumbo jets like the 747 and the Airbus A380, said Teal Group aviation consultant Richard Aboulafia.