These are the world's 7 worst aircraft carriers that are currently in service

China's Liaoning (16).

Commissioned in 2012, the Liaoning is a Kiev-class aircraft carrier that Beijing tricked Ukraine into selling by sending a Hong Kong businessman to purchase it under the guise of it being used as a casino in 1998.

The Liaoning was later commissioned in 2012, becoming China's first aircraft carrier.

But just a few years later, the Liaoning was spewing steam and losing power, and in at least one incident, a steam explosion blew out the ship's electrical power system.

Since then, the Liaoning has been rather unreliable, like most Soviet Kiev-class carriers, and used mostly as a training carrier.

Russia's Admiral Kuznetsov (063).

The Kuznetsov is a Kiev-class carrier that is currently undergoing repairs and won't be ready for service until 2021.

In October 2016, the Kuznetsov was sailing to Syria through the English Channel on a combat deployment when it was spotted belching thick clouds of black smoke.

"The main problem with the ship is that is has a very problematic propulsion system," Dmitry Gorenburg, a senior research scientist at the Center for Naval Analyses, previously told Business Insider. "It's just unreliable."

Commissioned in 1995, the Kuznetsov experienced a serious breakdown in 1996, and wasn't available again until 1998.

The National Interest recently even placed the Kuznetsov on its list of 5 worst aircraft carriers ever built.

Take a tour of the Kuznetsov here.

Thailand's Chakri Naruebet (911).

Commissioned in 1997, the Chakri Naruebet was once a fleet carrier, but was later relegated to a helicopter carrier in 2006, mostly because of budgetary issues.

Although the Chakri Naruebet was used after the 2004 Indian Ocean tsnuami and in rescue operations after flooding in Thailand in 2010 and 2011, the carrier has mostly resided in port for much of its 20-year career with the Thai Navy.

So while the Chakri Naruebet has not necessarily suffered from design flaws or repeated maintenance issues, we included it on the list because it's simply not being used for what it was supposed to.

Read more about the Chakri Naruebet here.

America's USS Wasp (LHD-1).

The Wasp is an amphibious assault ship that was recently fitted to carry F-35Bs.

But until then, the Wasp was conspicuously absent from major deployments from at least 2004 to 2011.

A Navy spokesman said in 2013 that it was because the ship was being "configured to serve as the Navy's Joint Strike Fighter test platform," but that reason only accounted for the years 2011-2013.

"That's a CYA [cover-your-ass] reason. That is not the reason it's not deploying," a retired Marine general told the Marine Times in 2013. "It doesn't seem to make sense to keep one of these ships out of the deployment rotation for so many years."

Although F-35Bs have since touched down on the Wasp, and it departed its homeport in Japan for a mission in the Pacific in early August, something might still not be exactly right with the ship.

"If people are worried about a hollow force, this is a hollow ship," a congressional analyst told Military Times in 2013.

Australia's HMAS Canberra (L02).

Commissioned in 2014, the HMAS Canberra is a Landing Helicopter Dock carrier, and one of two for the Royal Australian Navy.

Although the Canberra took part in RIMPAC 2018, it was sent back to port in March 2017 with serious propulsion problems.

It was expected to take only about seven to 10 days to resolve, but in May 2017, the Canberra was still undergoing repairs in dry dock.

"It may well be a design issue," Rear Admiral Adam Grunsell told ABC in May 2017.

One of the problems appeared to have been that faulty engine seals were leaking oil into different engine areas.

HMAS Adelaide (L01).

Commissioned in 2015, the HMAS Adelaide is Australia's other Landing Helicopter Dock carrier.

The Adelaide also took part in RIMPAC 2018, but it was sent back to port at the same time in 2017 as the Canberra with the same problems.

Given that both ships, which were commissioned around the same time, had similar problems at the same time, might very well hint at design problems.

America's USS Gerald R. Ford (CVN-78).

Commissioned in July 2017, the USS Gerald R. Ford is the most powerful and capable supercarrier ever built — but it's been dogged by repeated problems and is still not ready for combat a year after it entered service.

In April 2017 and January 2018, the Ford was sent back to port after experiencing a “main thrust bearing” failure.

In May 2018, the Ford was at sea undergoing trials, when its propulsion system malfunctioned, forcing back to port again after only three days.

The Ford has also had issues with the state-of-the-art Electromagnetic Aircraft Launch System and Advanced Arresting Gear systems designed to launch and recover airplanes, which have suffered repeated delays, despite recent reports of progress.

The Ford's AAG caught its first C2-A Greyhound aircraft in late May, according to General Atomics Electromagnetic Systems.

When we reached out to renowned ship expert Eric Wertheim about our inclusion of the Ford in this piece, he pushed back.

"It's important to give new complex warships and weapon systems time to mature through operational experience," Wertheim told Business Insider in an email. "If you had looked at many of the most successful weapons and warship designs, they often might have looked like miserable failures early in their life cycle, but they eventually turned a corner."

"If a warship is still underperforming its mission after a decade or more, it's probably not a very sound design," Wertheim added.

You can take a tour of the Ford here.