The World’s Heaviest Plane: The Story Of The An-225

The Antonov An-225 is the heaviest and longest operational aircraft today. It was built during the 1980s to serve a specific purpose within the USSR space program, but has gone on to serve a niche role carrying the heaviest of payloads. Already over 30 years old, it has just finished a further refurbishment, and we are likely to see it carrying out special missions for more than another decade.

The An-225 can carry a payload of 250 tonnes. Photo: Getty Images

The world’s heaviest plane

There are several ways that you can measure the largest aircraft. By passenger volume, of course, it is the A380. By fuselage volume, it is the Airbus Beluga XL.

The World’s Heaviest Plane: The Story Of The An-225
Beluga XL. Photo: Airbus

But the Antonov An-225 tops the list in a few areas. It is the heaviest aircraft ever built and can carry the highest payload (with an empty weight of 285 tonnes and a payload of 250 tonnes).

It is also the longest (at 84 meters, beating the new 777-9 by almost eight meters). And it has the largest wingspan of any operational aircraft (the new Stratolaunch beats it, though). If that’s not enough – it also has 32 wheels and six engines.

With a wingspan of over 88 meters, there are many airports where the An-225 cannot operate. Photo: Dubai Airports

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Built for a specific purpose

The Antonov An-225, also known as ‘Mriya’ (meaning ‘dream’), was built by the USSR (within the Ukrainian SSR) in the 1980s. At the time, the USSR was developing a reusable space vehicle known as Buran – similar to the US Space Shuttle. Construction of the Buran spacecraft began in 1980, and it flew once only in 1988. It was launched using a single-use rocket called ‘Energia.’

Just like the US Space Shuttle, Buran needed to be moved from the construction site to its launch area and recovered after its return. The An-225 was designed and built for this purpose. It could transport the Buran spacecraft on top of its fuselage, with internal space used for parts of the rocket.

An-225 with Buran orbiter
The An-225 with the Buran orbiter. Photo: Vasiliy Koba via Wikimedia

The US used a similar solution, of course. NASA had two Shuttle Carrier aircraft, developed from the Boeing 747. These had both previously been in service with airlines and underwent extensive modifications.

The first was a 747-100, acquired from American Airlines. It entered service in 1977. The second was a 747-100SR previously used by Japan Airlines on its high-capacity domestic routes. It first flew with NASA in 1991. The Shuttle Carriers remained in service until 2012, and both aircraft have been preserved in US museums.

NASA Shuttle Carrier
NASA used modified 747-100s as Shuttle Carrier aircraft. Photo: Carla Thomas, NASA/DFRC via Wikimedia

Based on the An-124 aircraft

The An-225 was developed as an enlarged version of the already operational An-124. This was likewise designed by Antonov during the 1980s and first flew in 1982. It entered service two years before the An-225 in 1986. It remains one of the largest aircraft still flying today.

Today, 24 An-124 aircraft remain in use (according to data from Six of these are operated by Ukrainian airline Antonov Airlines, six by Russian airline Volga-Dnepr, six by Voyennaya Transportnaya Aviatsiya and one by UAE-based Maximus Air Cargo. The rest are operated by the Russian Air Force. They fly regular cargo missions all over the world – including plenty of use during the pandemic.

The World’s Heaviest Plane: The Story Of The An-225
The Antonov An-225 was developed from the ‘smaller’ An-124 – still one of the largest aircraft flying today. Photo: Getty Images

Design changes

Basing the design on the An-124 saved development time and cost. The same fuselage structure and engines (Progress D-18T engines) were used. Engines were increased to six and the fuselage was extended by around 15 meters.

To remove weight and better handle the top-loaded payload, Anotonov removed the rear cargo access. But it retained the same opening nose and the lowering nose gear, which allows the aircraft to ‘kneel’ to load cargo. You can see this in action in the video below.

Engineers also changed the tail design from the An-124. The single vertical stabilizer was switched to a twin tail, with two vertical stabilizers and a larger horizontal stabilizer. This would provide better handling with the large payload on top of the aircraft.

An-225 tail
The An-225 has a distinctive twin tail. Photo: Getty Images

Construction of the fuselage, tail and the final assembly took place at Antonov’s facilities in Kyiv. The wings and wing center were built by the state-owned Uzbekistan company Valerii Chkalov in Tashkent and transported to Kyiv using the An-22 transporter.

In service with Antonov Airlines

The Buran spacecraft only flew once on an unmanned launch. It successfully returned, but planned future launches never took place. The collapse of the USSR led to the suspension of the space program. Two further orbiters were never completed, and the one existing Buran was stored in Kazakhstan. It was destroyed when a hangar roof collapsed in 2002.

The An-225 suffered a similar decline – at least initially. After use for the first Buran flight, it made appearances at the Paris Air Show in 1989 and the Farnborough Air Show in 1990. It went into storage in 1994, with the six engines removed and re-used on An-124 aircraft.

By the late 1990s, Ukrainian Antonov Airlines saw potential in returning it to service as a freighter capable of carrying larger payloads than the An-124. Engines were re-installed, and the cabin floor and nose ramp were strengthened (as the original design was to carry external payload). It returned to operations in February 2001.

Antonov Airlines operates the sole An-225. Photo: Dubai Airports

There is a second aircraft

Two An-225 were originally ordered, but only one aircraft (with registration CCCP-82060, later changed to UR-82060) was completed. The first was under construction when the Buran project ended and was never completed.

Ukrainian Antonov Airlines also took ownership of the second aircraft but did not continue construction. Work started again in 2009 and took it to around 60 to 70% complete. There was interest in 2016 from China and reports about a potential sale to the Airspace Industry Corporation of China.

It remains unfinished, and according to comments from Antonov Airline’s CEO Oleksander Donets in 2020, it most likely never will be completed.

The second An-225 remains uncompleted. Photo: Getty Images

Completion remains very expensive, and it is unlikely that anyone would recover the costs with its limited potential operations – despite the increase in freight traffic recently. Donets said:

“According to estimates made in 2012, when our relations with (Russia) were good, (the costs of construction) has reached nearly $460 million for the old specifications it was built with….. Most importantly, nearly 35 percent of (the world’s) airports can’t provide landing space (for Mriya). Because of its dimensions and wingspan, it doesn’t fit runway strips… We will not recoup the costs.”

The An-225 remains well in use today. It was brought back into service to use for outsize cargo charters. This is, of course, a niche market. But with the highest payload possibility of any freighter available, it is something that clients will pay for.

The single aircraft remains owned and operated by Antonov Airlines. It has previously seen operating partnerships with UK-based Air Foyle HeavyLift and Russian cargo operator Volga-Dnepr Airlines (which operates the largest commercial fleet of An-124 aircraft still in service). The restored aircraft received its type certificate in May 2001.

The An-225 carried medical supplies to Germany in 2020. Photo: Getty Images

Plenty of charters

The aircraft sees around several charters each year. This has included plenty of oversize, heavy cargo such as generators and construction equipment, military equipment, and large humanitarian loads. If you are wondering about the cost of chartering it – the BBC estimated it to be around $30,000 per hour in its analysis.

Some of the more interesting include:

  • One of its first missions was to fly food from Germany to an American military base in Oman, in January 2002. It carried 187.5 tonnes of prepared meals for troops.
  • In June 2004, it flew with four pipe-laying machines from Prague to Tashkent, setting a payload record of 247 tonnes.
  • It set the record for the heaviest single cargo item in August 2009 – flying a 189-tonne generator to Armenia for implementation in a gas power plant.
  • It carried the longest ever air cargo in June 2010 – two 41.2 meter wind turbine blades from China to Denmark.
  • Several medical missions have taken place during the pandemic. This included a record for cargo volume on April 14th, 2020, when it carried 1000 cubic meters of equipment from China to Poland. And two weeks later it carried 150 tonnes from China to France.
An-225 cargo
An-225 with military cargo. Photo: Antonov Airlines

Future for the An-225

The An-225 remains actively in use for cargo missions. With the current high demand for cargo (caused in part by fewer passenger aircraft flying and carrying cargo), this looks set to continue. The grounding of Volga-Dnepr Airlines’ An-124 fleet after an accident in November 2020 has also boosted the use of the An-225.

The airframe is, of course, aging – in 2021, it is already 32 years since its first flight. But it has seen much less use than a standard commercial airliner. Antonov Airlines has previously claimed it would have a lifespan of 45 years and is expected to remain in service until at least 2033. An 18-month refurbishment that ended in late 2020 helped to prepare for this.

With lower utilization, the life of the An-225 could easily reach 45 years. Photo: Dubai Airports

There is another use that has been discussed for the An-225. It could carry spacecraft to altitude for launch into space. China was interested in this when it considered purchasing an aircraft. This never happened, though, and it would be an expensive change of use.

It has competition too in this niche area, from a much newer aircraft. The first Stratolaunch (full name Scaled Composites Model 351 Stratolaunch) aircraft took to the skies in 2019 and is now owned by Cerberus Capital Management. It remains in testing but was designed to carry a rocket, weighing up to 250 tonnes, between the fuselages for launch into orbit. Under new owners, its role will shift role to a launch vehicle for reusable hypersonic flight research vehicles.

The new Stratolaunch aircraft will carry other vehicles between its two fuselages. Photo: Stratolaunch

The An-225 is an amazing aircraft and fills a niche role. Have you ever seen it in action? Feel free to share your experiences in the comments.