The Antonov An-124 Ruslan was built in the 1980s as a strategic military airlifter for the USSR.
Both Ukraine and Russia have used the giant quad-engine freighter in the ongoing war effort.
Two engines from Ukraine's destroyed An-225 jet have been salvaged and sent to its An-124 fleet.
The world's largest airplane, the Antonov An-225 "Mriya," was destroyed in February 2022 after Russia's attack on Hostomel Airport near Ukraine's capital of Kyiv.
Ukraine has been busy salvaging what it can of the jet since March 2023, with three engines actually being repaired and sent to the fleet of An-225's sister jet: the Antonov An-124 Ruslan, a heavy-lift plane operated mostly by Russian and Ukrainian carriers.
Take a look at the giant aircraft, which has faced serious headwinds since Moscow's full-scale invasion of Ukraine.
Originally built as a heavy strategic airlifter for the USSR, the Ukrainian-made An-124 took its first flight in December 1982 and eventually entered the Soviet Air Forces in 1986.
Although Ukraine was still part of the USSR when the An-124 was built, the Antonov Company — then known as the Antonov Design Bureau — remained a part of Ukraine after the country's independence in 1991.
Several versions of the Ruslan have since been produced, such as the AN-124-100 commercial transport plane and the 150-tonne-payload AN-124-100M-150 variant.
The original Ruslan was built for military transport, running long-range delivery missions, and air-dropping heavy cargo equipment, as well as troops.
The AN-124-100M-150 commercial freighter is the latest version of the Ruslan airlifter, having been modified to increase the payload capacity to a little more than 330,000 pounds and fly nearly 400 miles farther than its predecessor. Its maximum takeoff weight is about 886,000 pounds.
Its current-day commercial use has seen it carry things such as oil-drilling machines and aircraft engines.
Designed to carry awkward and oversize objects, the huge planes are powered by four Ukrainian-made Progress D-18T engines and sport a total of 24 wheels.
The An-124 was actually the precursor to the An-225, which was built at the request of the USSR to carry its Busan Space Shuttle.
A quick turnaround time required by the Soviets meant it was more efficient just to create a larger version of the already-proven Ruslan.
What makes its missions easier is the plane's unique nose-loading door — something that was also incorporated on the Mriya.
The nose-loading door is only featured on a few other mammoth cargo planes, such as the Boeing 747 freighter, the US Air Force's Lockheed C-5M Super Galaxy, and Airbus' Beluga transporter.
The Ruslan has earned a number of Guinness World Records over the decades, carrying odd objects such as generators and trains.
In 1993, the AN-124-100 carried a Siemens generator weighing 124 tonnes from Frankfurt, Germany, to New Delhi, making it at the time the heaviest single piece of equipment ever airlifted.
A year later, General Motors tapped Antonov to fly a 109-tonne locomotive from Ontario, Canada, to Dublin, Ireland. The journey took 12 hours, including two refueling stops, and set a record for transporting the "heaviest cargo (plus equipment) of 146 tons."
Only about half of the 55 An-124s built between 1982 and 2014 are still in service — most of them flying for Russia or Ukraine.
The Antonov Company subsidiary Antonov Airlines operates five An-124 aircraft out of Germany on behalf of NATO and the Ukrainian government. The jets are also flying on some humanitarian missions.
Data from Planespotters indicates the Kremlin has 21 An-124s across cargo carrier Volga-Dnepr and the Russian Air Force. Several of which, however, have been confiscated after Western nations imposed sanctions against Moscow.
Now that the Mriya is gone, the An-124 aircraft has become the world's largest civil freighter — boasting a 10,000-tonne greater cargo hold compared with the C-5M Super Galaxy.
Ukraine's An-124 stands about 68 feet tall and 227 feet long with a 240-foot wingspan. Its 150-tonne payload is greater than the 140 tonnes of weight the C-5M is capable of carrying.
The An-124 fleet across both Russia and Ukraine has, however, faced significant challenges since the war began.
A handful of the world's fleet of An-124s are either damaged or seized, even forcing Antonov to relocate from Ukraine to Germany after the destruction of Hostomel airport.
According to Antonov, one of its An-124-100s was destroyed at Hostomel, while another was damaged and taken out of service for further evaluation.
The company said in May 2022, "As a result of the Russian attack and occupation of the airfield, significant damage has been caused to its infrastructure, office buildings, hangars, as well as the destruction of the AN-74T, AN-26-100, and AN-225," Simple Flying reported.
Another of the five surviving An-124s actually narrowly avoided destruction when it took off from Hostomel airport just one hour before Russia's attack, Aviacionline reported.
Russia has also faced a string of challenges, including four of its An-124s being seized in Canada and Germany.
Planespotters indicates eight of Volga-Dnepr's 10 Ruslans are parked. Aerotime Hub reported four of these were stuck abroad including one in Canada and three in Germany.
The solo An-124 sitting in Canada was confiscated following Russia's invasion of Ukraine and subsequent sanctions against the Kremlin.
Canada is now set to hand the An-124 back over the Ukraine to help with its continued war effort against Russia.
Even though Ukraine has lost a few of its An-124s, the Ruslan is still an important asset in the ongoing war effort.
Over the months, the An-124 has been used to deliver military cargo like the armored vehicles moved from Australia to the Ukrainian army in May 2022.
And, although the Mriya is now out of commission, it's still able to support the An-124 fleet thanks to some salvageable parts.
Ukrainian journalist and photographer Igor Lesiv, who visited the destroyed An-225 in August, told Insider that three of the jet's six engines could be saved — two of which went to the An-124 fleet.
"D-18T engines were always rearranged between AN-225 and AN-124, so they are now used on Ruslans," he said.
Several other parts from the An-225 have also been saved, which the country hopes can one day be used to rebuild the beloved Mriya.
Ukrainian President Volodymyr Zelensky and the Antonov Company have announced commitments to rebuilding the legendary Mriya — a feat the country estimated in November to cost about $500 million.
Correction: A previous version of this story misspelled Mriya in nearly all instances. It has been corrected.
Read the original article on Business Insider