Celebrating an aviation legend

(CNN) -- In the world of aviation there are some aircraft that hold a special place in history and become legends of the skies.

The DC-3 was such a plane, mixing design, economics and durability in a combination that would revolutionize the airline travel industry.

By today's standards it might not look like much: twin propellers, a chunky metal body and none of the sleek, sophisticated design of a modern aircraft.

Nevertheless, the DC-3 remains one of the most famous and best-loved planes ever built.

Like many great designs, the aircraft was the product of competition -- a fierce rivalry between Douglas aircraft and Boeing years before the two manufacturers would merge.

A marathon phone call with the head of American Airlines gave Donald Douglas his brief: build a plane for passengers to compete with trains, and the Boeing 247 being flown by United Airlines.

The result was airborne in December 1935.

The DC-3 was one of the first airplanes designed with passenger comfort in mind.

Some of the originals had flat beds and curtains on the windows. Although it was noisy by today's standards, in its day it was one of the quietest around.

It had the latest in technology, an autopilot, a retractable undercarriage and an aerodynamic nose.

But its biggest assets were reliability, safety and durability -- the wings were so strong that not even a bulldozer could crush them.

A bigger dent was made in U.S. travel, providing airlines with their first profits independent of subsidies or mail contracts.

"Prior to the advent of the DC-3, crossing the States was something of an obstacle race and certainly an endurance race. It took around 18-20 hours," aviation historian Hugh Cowin told CNN.

"The DC-3 took it down to 14 trans-Atlantic and that made air travel a lot more credible in a lot more people's eyes."

Soon, orders were mounting as the DC-3 carried the global surge in commercial aviation.

Military orders pushed production beyond 10,000, mainly with the DC-3 modified as the C-47, also known as the Dakota.

It also gained a permanent place in the hearts of passengers and crewmen like World War II mechanic Alan Hartley.

"They were a wonderful aircraft and so safe. As a mechanic, we had very little to do, they were so reliable the Dakota," he said.

And today, 70 years from their first flight, about 200 of the planes remain in operation -- a tribute to this legend of the skies.

CNN's Jim Boulden and Andrew Demaria contributed to this report.