Atlanta-based Delta Air Lines is worth $37billion (£28billion) and flies to 370 destinations on six continents with state-of-the-art aircraft.
But it started life as a crop-dusting outfit in 1924.
And when it expanded to passenger transportation it used planes that could only hit 90mph, with the wind behind them.
Delta has been on quite a journey, then and these fascinating pictures illustrate the carrier’s dramatic transformation over the decades.
Pictured is a restored 1931 Curtiss-Wright 6B Sedan, first-ever passenger aircraft, the Travel Air S-6000-B, which flew Delta’s first passengers on June 17, 1929.
Air speeds jumped in 1936 with the 190mph Lockheed Electra 10, Delta’s first all-metal plane.
It had the capacity for 10 passengers and had 450 horsepower, thanks to two Pratt & Whitney Wasp engines.
It also had retractable wheels – which practically rendered it space-aged for the time.
Passenger comforts included hat nets, window curtains, reading lamps and ashtrays. And with the Lockheed 10, Delta introduced its first onboard meal service box lunches and coffee, served by the co-pilot.
Air travel with Delta took a big step forward in 1940 with the Douglas DC-3.
It could hit 170mph, had to room for 21 passengers and had a range of 500 miles.
It revolutionized commercial aviation.
By 1940, DC-3s carried 80 percent of the world’s airline traffic
This had a relatively huge range of 2,000 miles and could cruise with up to 44 passengers on board at 215mph.
A Delta DC-4 flew the world’s first nonstop scheduled flight between Chicago and Miami on November 1, 1946
It’s 1953, the pressurized cabin, thanks to the Lockheed Constellation, which had, Delta says, ‘nonstop transcontinental capability’.
It operated between 1953 and 1958, could hit 327mph and had a range of 1,800 miles.
It flew domestic and Caribbean routes.
It had a range of 2,760 miles, a top speed of 360mph and developed 3,250 horsepower.
The cabin features were quite something for the time gold window curtains, typewriters for those who wanted to work, complimentary Champagne, entrees at mealtime and canapes and cocktails on afternoon flights.
A 1956 Convair 440, which had a range of 580 miles and a top speed of 284mph.
Delta’s last Convair 440 retired in 1970 when its fleet became 100 percent jet-engined.
It launched in 1947 with Douglas C-47 freighters and had grown by 724 percent by 1956.
In 1957 new Curtiss C-46 aircraft (pictured) were delivered.
Delta boasted that they were big enough to load a Cadillac automobile without scratching the paint job.
The Curtiss C-46 remained in service until 1966.
On delivery day, July 22, 1959, flew the 2,497-mile route from the Douglas plant in Long Beach, California, to Miami in 4 hours and 43 minutes.
The previous record on the route had been 5 hours and 50 minutes set by a Douglas DC-7.
The DC-8 produced a hefty 13,500 horsepower and could reach 590mph.
Two years later a Convair 880 set a new Delta speed record – hitting 715mph on a flight from Chicago to Miami and taking just one hour, 50 minutes and 55 seconds to complete the 1,258-mile flight.
After almost a 16-year absence, the DC-9 rejoined Delta’s fleet during the Northwest merger in 2008 and flew until January 2014.
Delta was the first and the last U.S. airline to fly scheduled DC-9 commercial flights.
They had a top speed of 575mph and a range of just over 2,000 miles.
Its top speed was 361mph.
Delta 747s offered the ‘world’s first flying penthouse apartment’, located above the First Class cabin and adjacent to the First Class lounge.
It had seats for six passengers and was sold as a unit.
It had its very own flight attendant.
The 747 has a range of 6,000 miles and a top speed of 625mph.
They were retired in 2003.
They could cruise at 566mph and had a range of 1,950 miles.
They had the capacity for 250 passengers, could cruise at 552mph and in-flight entertainment included ‘seven mood-matching channels of Deltasonic stereo words and music programs’.
Delta’s first movies were shown on its transatlantic L-1011s in 1978.
Delta says the 767-200’s technical advances included a new advanced wing design that allowed for a more efficient lift for a quick climb to cruising altitude, a digital “glass cockpit” with 40 computers and engines that were 30 percent more fuel efficient’.
The first model, the 757-200, was 45 percent more fuel efficient than the Boeing 727 it replaced.
In 1992, Delta received the 500th 757 made by Boeing and since 2007 has operated the largest 757 fleets in the world.
It had a cruise speed of 543mph, a huge range of 8,460 miles and aerodynamic enhancements, including winglets.
The cabin, meanwhile, has optimized pressure, temperature, and humidity.
Delta says that the customer service at the time was ‘industry-leading’.
Even in economy, passengers had personal in-seat videos, adjustable footrests, headrests, and lumbar support.
And the pilots were in another world, too.
They had satellite communications, GPS, predictive windshear and collision avoidance systems and enhanced ground proximity warning systems.
The 777 is still going strong today.
It has a carbon-fiber-reinforced plastic fuselage with increased resistance to corrosion and the pilots have all sorts of gadgets at their fingertips.
For example, ‘brake to vacate’, which applies the correct amount of braking automatically to bring the aircraft to taxiing speed at the desired runway exit, graphics of the ‘wing shape’ and screens that display everything from fuel levels to runway layouts.
Introduction: 15 January 2015
Status: In production, in service
Produced: 2010 – Present
Number built: 265 as of 30 April 2019
Program cost: €11 Billion
Unit cost: US$317.4 Million