In the course of just a few months, Delta Air Lines (DL) made headlines numerous times for several fleet-related news.

Delta was in the spotlight for completion of their Bombardier CSeries order, the entry-into-service of their first Airbus A350-900, and most recently, for the order of 100 new Airbus A321neos.

As new aircraft continue to flow into the Atlanta-based carrier’s fleet, these appear to be replacing nearly every last corner of an elder, diverse squad of airliners, both on the domestic and long-haul front.

Delta’s short/medium-haul fleet consists of 171 MD-80/90 planes, averaging 24.8 years old; 91 Boeing 717s, averaging 15.7 years old; 125 Boeing 757-200/300s, averaging 20 years of age; and 64 A320s, which average 22.3 years old.

Furthermore, their widebody fleet consists of 82 Boeing 767-300/400s, averaging 20.3 years; 18 Boeing 777-200(ER)/(LR), averaging 13 years of age; and 42 Airbus A330-200/300, averaging ten years of age.

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Adding up all these numbers, the Delta fleet hovers around 17 years of age—by far the oldest of any American legacy carrier.

Delta also tends to catch some attention by purchasing many of their aircraft second-hand—a rarity for a large American carrier.

All of their Boeing 757-300s, and Airbus A320-200s—some of the oldest, yet prominent, aircraft in the Delta fleet—were obtained through a merger with Northwest Airlines in 2009.

The rear fuselage section of the first Boeing 757-300 is lifted into place on the assembly line at the Boeing factory in Renton on March 19, 1998. The 757 production line is now the site of the 737’s 2nd production line. (Credits: Boeing)

Likewise, the Boeing 717s in Delta’s fleet are mostly on a lease agreement with Southwest Airlines, who acquired these jets following their merger with AirTran Airways.

Looking down upon a 717 from the Concourse A ramp tower

Rejuvenating Motion

The past few years have seen a series of changes in how Delta operates their fleet. Beginning in September of 2013, the airline started to make a flurry of orders from numerous manufacturers.

On September 4 of that year, an order was placed for 30 Airbus A321s, and 10 Airbus A330-300s. About nine months later, 15 more A321 orders were set, followed by 25 A330neos and 25 A350-900s.

In late 2015, 20 Boeing 737-900(ER) aircraft were booked, which preceded a great order for 75 Bombardier CSeries CS100 aircraft with options for 50 more.

The first flight of the 737-900 on August 3, 2000. Launch customer Alaska Airlines received the first of 10 airplanes in May 2001. This model was replaced in 2005 with the 737-900ER. (Credits: Boeing)
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As if things weren’t enough, Delta booked an additional 37 A321s and ten 737-900(ER)s, followed by a further 40 A321ceos one year later.

And a couple weeks ago, Delta closed its order books by booking 100 A321neos—considered a major blow to Boeing and its 737 MAX program.

PHOTO: Airbus.

During these few years, orders for Embraer E190s and Boeing 787-8s were canceled.

An Impressive Tally

Throughout these four years, a total of 387 brand new aircraft were ordered, consisting of narrow-body and wide-body, short-haul and long-haul alike.

These aircraft were brought in not only as supplements to the current fleet but also as replacements. The A321s and 737-900(ER)s will replace Delta’s aging fleet of MD-80/90s, Boeing 737-700/800s, and Boeing 757s.

The new A330neos and A350s will replace their Boeing 747s and 767-300(ER)s.

Delta also seeks to refurbish many of their existing aircraft, adding DeltaOne Suites to their widebodies (excluding the 767), and currently completing interior renewals of their A320 aircraft.

The Bombardier CSeries CS100 aircraft will also replace some short-haul planes in the airline’s regional division, as well as the oldest McDonnell-Douglas MD-88s. However, following the heated Boeing vs. Bombardier spat that aroused after Delta decided to purchase the CSeries instead of the 737, replacing the venerable Maddog might be indefinitely postponed.

aerial view of Lausanne and Lac Leman (Bombardier CS100).
READ MORE: Delta Orders 100 Airbus A321neos, Says No to Boeing’s 737 MAX

Among some other assorted retirements of individual aircraft, Delta’s 767-300s, older 767-300(ER)s, and MD-80s are all on the list to be retired over the next two to three years, and will likely be followed by the MD-90s, 757-200/300, and A320s in the years after.

A Delta Air Lines Boeing 757-200 parked at the gate in CCS.

While these aircraft remain functional and hardy, their logbooks are full, and many just cannot keep up with the efficiency being brought by Delta’s newer airplanes or justify their continued presence in the fleet.

While these soon-to-be rare and sparse aircraft will undoubtedly be missed by passengers and aviation enthusiasts alike, it can undoubtedly be said that Delta is in the middle of a huge fleet revival, one that is only just beginning.

For an airline accustomed to these historic aircraft, such a makeover may be difficult to swallow – even if the tradeoff is countless new “Delta bellies” filling the skies for years to come. However, one thing is sure: these brand-new aircraft will be shining with history – and with a touch of progress.