A guppy might be prey, but the Super Guppy is a predator. The bloated aircraft has been retired by every institution in the world except for one: NASA. The U.S. space agency finds the Guppy’s wide dimensions perfect for transporting spacecraft and rocket components.

The first Super Guppy was constructed from a ballooned fuselage taken from a Boeing C-97 Stratofreighter, which first flew in 1965. The turboprop cargo plane was largely replaced by the Airbus Beluga for large and awkwardly shaped cargo delivery, but as long as NASA still has a use for the Super Guppy, it will continue to baffle people in the sky—and NASA loves the Super Guppy.

With a payload capacity of almost 135 tons, the C-5 Galaxy is the largest aircraft routinely operated by the U.S. military. The Air Force announced it was reactivating the monster airlifter in May 2017.

The C-5 has enough cargo space to carry two M1 Abrams tanks, 16 Humvees, three Black Hawks, or a variety of other vehicles. Without cargo, the C-5 can fly up to 7,000 miles without refueling, making it the longest-range military airlifter in the world. When the Air Force needs a lot of tonnage moved quickly, it turns to the C-5.

In the 2000s, Boeing found it needed a cargo plane with an enormous amount of storage to transport components for the 787 Dreamliner, which has parts made all over the world. The solution was to take its biggest plane, the 747, and build a custom cargo hold around it.

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At 65,000 cubic feet, the Dreamlifter has the largest cargo hold in the world, capable of carrying three times the volume of a 747-400F freighter. The four Dreamlifters Boeing made also use the longest cargo loader in the world, and can haul payloads up to 125 tons.

Here’s another monster designed and built by the Antonov Design Bureau. The An-124 Ruslan, operated by the Russian Air Force, is the largest military aircraft in the world. For almost 30 years after its introduction in 1984, the An-124 (NATO reporting name: Condor) was the largest and heaviest cargo aircraft in the world, besides the single An-225. The 747-8F overtook the An-124 in 2011.

With a reported payload capacity of 165 tons, the An-124 can haul even more than the C-5 Galaxy, though its range isn’t as long. A surviving engineering triumph of the Soviets, the An-124 continues to fly airlifting missions for Russia.

The B-52 entered service in 1955, and the first B-52H, the current model, debuted in 1961. The B-52 bomber is the grandfather of the air force: aging, but still capable of delivering a serious punch.

The BUFF (Big Ugly Fat F***er) can carry 70,000 pounds of weapons, from precision-guided conventional bombs to nuclear warheads. While the B-2 stealth bomber and B-1 supersonic bomber could be retired when the B-21 is introduced, the Air Force wants to outfit the reliable B-52 with new engines to improve efficiency and range.

While the giant bomber enters its sixth decade of service, the technology within its hold is ever-evolving, as the Air Force is also planning to equip the B-52 with the Long-Range Stand-Off missile, a stealthy nuclear cruise missile.

This Soviet-era long-range transport aircraft is a certified workhorse. It has a 164-foot wingspan, can transport up to 140 troops, and has a max payload of up to 50 tons.

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Designed to operate in extreme conditions, the Ilyushin Il-76 prototype made its debut in 1971 and went into production three years later. (It can take off and land on short, unpaved runways and can fly through difficult weather with ease.) More than 800 of them were built, according to Military-today.com, and it is still widely used by multiple countries today.

Step aside, Beluga. There’s an even bigger whale in town.

Developed in 2014, the BelugaXL flew its first operational flight in 2020 after more than 200 test flights. It has officially joined Airbus's already behemoth fleet to move certified Big Things around the world.

The plane is massive. It’s 206 feet long and has the largest cross section of any cargo plane in the world. A pair of Rolls-Royce Trent 700 turbofan engines help keep the hulking plane airborne.

It’s got a leg—er, wing—up on the previous A300-600 Super Transporter. The BelugaXL can haul not one, but two of the massive A350 XWB’s wings. (The first generation Beluga can only carry one.)

The Dreamlifter is already on the list, but it only represents a small part of the accomplishments of the Queen of the Skies. Boeing has built over 1,500 Boeing 747s, and the planes have served as the largest passenger and cargo aircraft in the world, a military command center in the sky, Air Force One, and a space shuttle lifter and infrared telescope flier for NASA. Plus, Iron Maiden even has one called Ed Force One.

The aircraft is being phased out of airlines in favor of single-aisle designs that can now fly with enough range to cross the oceans. But as the only U.S. mass-manufactured four-engine jumbo jet, the Boeing 747 has some years in it yet.

The C-5 Galaxy may be the U.S.’s biggest military plane, but the C-17 Globemaster is the primary workhorse. The aircraft took its first flight in 1991, and 279 Globemasters have been built since.

The C-17 airlifter can haul about 85.5 tons into the sky, flying missions around the world to transport troops and cargo, perform airlifts and medical evacuations, and fly airdrop routes.

The Airbus A380 is the European 747, and the A380-800 is the largest passenger aircraft ever made, with room for 850 passengers. It flies some of the longest routes around the planet, but like the 747, it may be starting to get replaced with smaller planes with similar range.

The Airbus A380 is truly the world’s flying bus, flying more people at a time than any other plane in history.