Traveler, 27, tests ALL major domestic airlines and private jet carriers in the US to create ultimate ranking in week-long saga that left him in TEARS - and revealed very surprising results

A YouTube prankster decided to try out every airline based in the United States, a rollicking adventure that kept him confined to 'the airport system' within the country for a week straight.

Eric Decker, 27, who goes by Airrack on YouTube, where he boasts nearly 15 million subscribers, decided to 'dedicate however many days of my life it takes to try every single airline in the country.'

All the while, he teased in his latest video that he had the 'best seat' in the country booked for the final leg of his journey, on an American Airlines flight, that would take him home to Los Angeles.

He embarked on the sky-high endeavor, with an itinerary spanning all 28 domestic airlines, with 'three simple rules' in place. 

First rule: He was 'not allowed to leave the airport system' - that is, all the action must be confined to planes and airports - until the mission was complete. 

Second rule: He must 'buy the nicest seat' the airline will sell him, and then will rate the experience on: price, comfort, service, and 'the X-factor,' adding of the latter that he wanted 'to leave these airlines room to surprise me.'

Third and final rule: All eating, drinking, bathroom usage and sleep must be done on a plane or in an airport.

'Live by the plane, die by the plane,' Eric declared.

He also hauled along a carry-on filled with trophies, including 'Flight Attendant of the Year Award,' 'Best Captain Award,' and 'Coolest Person To Sit Next To Award,' to be distributed appropriately amidst his travels.

At the same time, Eric recruited friends on the ground to help him assess each airline - with Tyler Blanchard assigned to check out corresponding airport lounges, and Jack to review airplane bathrooms.

The goal was to put forth the most well-rounded possible assessment of each airline in assigning them a letter grade, from A to F.

With that, just above the A-grade level was an 'S-tier,' for extraordinary, above and beyond experiences. 

Departing out of LAX, first up was a United Flight. 

While Tyler gave the LAX United lounge a B, Eric decided to rank United a C thanks to delays.

Next up was a flight on Horizon. Almost as soon as everyone boarded the plane - which Eric 'immediately noticed… was about 120 degrees inside' -  the crew asked everyone to disembark. 

'This entire schedule relies on an extremely calculated flight plane, and one delayed flight could throw this entire thing off,' Eric fretted.

But, instead, the worst case scenario happened, and the Horizon flight wound up being cancelled outright.

'Two flights in, Horizon Air had already destroyed my meticulous plan, which means I think that this is going to take longer than I thought it was going to,' Eric sighed.

Elsewhere, Jack was testing out bathrooms on Avelo and JSX, giving budget airlines Avelo a B and the private-jet charter airline JSX, with the fare at more than $1,000, earning a C. Then, still going primarily on the bathrooms quality, Jack rated Allegiant an A.

Meanwhile, Eric embarked on a Southwest flight - acquiring 'the best seat' in the first row on the plane.

On-board, the crew was polite, but Eric still rated Southwest a C, due to a four-hour delay.

Next up was the 'infamous' Spirit, the much-maligned budget airlines notorious for its absolutely no-frills approach to air travel.

Eric, however, had a good experience, sleeping 'like a baby' - and adding that the Spirit flight was the 'cleanest, smoothest, nicest staff I have interacted with this entire time.'

'I cannot believe I am saying this, but Spirit Airlines is B-tier,' he concluded.

Meanwhile, Contour, with a 'comedically small' plane, garnered a C. 

Envoy Airlines, owned by American, made it to the B-tier. 

The regional Silver Airways boasted as its mascot a pink flamingo, with their airplanes, uniforms, and even traffic cones on the tarmac, colored to match.

Though Silver seemed to start off strong, they lost serious points after deplaning everyone due to a mechanical issue. They then re-planed everyone for take off, only to stop the airplane, disembarked everyone, and cancelled the flight. 

Despite the pretty in pink aesthetic, Silver landed at an F.

Eric had a better experience at Frontier, where he sat next to a flight attendant named Tamisha - to whom he ultimately gave his 'Coolest Person To Sit Next To Award.'

Given the positive experience, he also awarded Frontier an A. 

Next up was the iconic Delta, of which fellow travelers Eric interviewed across airports consistently spoke highly. 

Seated on the Delta flight, Eric admitted that he felt weird filming given the 'classy' environment. Delta would have made it to S-tier, but, thanks to the higher price, Eric ultimately ranked it an A. 

Happily, at the end of the Delta leg of his trip, Eric landed in Chicago O'Hare, which has a Hilton on the premise.

'I immediately fell asleep,' he said.

However, by this point in his journey, Eric admitted he was starting to feel alone and isolated, like he was 'in purgatory.'

Elsewhere, Tyler's parents had surprised him at the airport for his birthday, and Tyler soon after gave up on reviewing airport lounges in favor of celebrating at a rented Malibu mansion.

On catching up with Tyler, Eric admitted his morale was at an all-time low.

But, as he'd done throughout the video, he continued to tease that the 'most comfortable seat in the country,' on an American Airlines flight, was awaiting him on the final leg of his travels. 

Another well-known airline, JetBlue, earned C-tier due to its 'jenky' seats.

He then took Sun Country to Las Vegas, noting the 'comfortable' seating and the 'unbeatable' price. 

From there, Eric was off to an Alaska Airlines flight. On this flight, he'd booked a seat near the exit door in a nod to the recent Alaska flight on which a cargo door flew off mid-flight.

Luckily, the terrifying incident was not repeated, and Eric thought his Alaska Airlines warranted an A.

Next up was Boutique Airlines - tagline, 'Fly Private for the Cost of Commercial.'

Indeed, the fare cost only $146 - 'one of the cheapest tickets for the entire video, for the nicest seat. It doesn't make any sense!'

The pilot also let Eric put a GoPro in his cockpit.

'If there's such a thing as an S-tier airlines, this was it,' Eric gushed. 'Free snacks, amazing service.'

Eric further presented the pilot with his 'Best Captain Award' trophy.

Last up was supposed to be the final  - and most luxe - leg of Eric's journey: the first-class seat on an American Airlines flight.

But, prior to boarding the final flight, which would have taken him back home to Los Angeles, Eric began getting emotional. 

'Tyler and I ended up talking on the phone for a while and it was sort of in this moment that I realized that something actually was wrong,' Eric admitted.

'I don't know why I'm emotional right now. I was just thinking about all of the people that we've met over the last six days.'

'They remind me so much of my own friends and family,' Eric continued, adding that his friends had also send him a video from a hot tub.

'And it makes me think about the fact that I've actually been gone for so long. Not just the six days that I've been doing this video, but the four years that I've been doing YouTube. 

'And it makes me think of my mom. My mom's name is Jean. She is the coolest lady I've ever met. Since I was a little kid, I wanted to do YouTube. And there's not a person that has supported me in whatever I want to do more than my mom, Jean. 

'And since I really started grinding on YouTube, I have not seen her nearly as much as I should.

'What I'm trying to say is, I think I decided that I'm going to cancel my flight home and book the first flight I possibly can to go find my mom,' he explained while tearing up.

'So I ended up giving up the best seat in the country, but at this point it didn't really feel like a sacrifice.

'I'm going to be honest, after flying 30 flights in a week it's all the same.

'The thing I feel like I learned over the last seven days was not which airline is the best in the US. I learned that if you're lucky enough to still have a mom you should call her. Or, if you can, book a flight!'

His video concluded with Eric surprising his mom at her front door.

Jean admitted she didn't like American, saying that they'd previously lost her baggage and determining that the airline should land at the E-tier, just one level above F.

'Let's go spend some time together,' Eric said to his mom, while embracing her.