For many years, airplanes have served as a reliable form of transportation, especially for long-distance travel. Travel — whether for business or for leisure — is supposed to be as fun, easygoing and seamless as possible. However, there are some airlines that are laid-back and some that are strict. The latter obviously is a bummer, but we feel the need to go over such a topic regardless of its negative aspects.

Not only do airline employees have to follow strict yet secret rules, but some airline passengers have to follow stern protocol as well. Obviously, there's a reason why air travel rules remain in place, but we believe they can be a bit overboard with the exception of preventative measures due to the current Coronavirus pandemic around the world.

From United Airlines to Czech Airlines, this list is likely going to make you think twice before boarding your next flight! Now, here are the 15 airlines with the strictest flying rules.

15 Complaining Is A No-No On Frontier Airlines

Let's start with Frontier Airlines. Not only does it allow each passenger one personal item with the maximum dimensions of 8" depth, 18" width and 14" height, it can also boot you off a flight if you're complaining, like, say, the father and daughter who grumbled about an eight-hour delay they had to sit through in 2017.

14 You Can't Wear Leggings On A United Airlines Flight

Remember when a United Airlines gate agent prevented two girls from boarding a flight because they were wearing leggings? Yeah, this rule was reportedly in United's passenger contract, notes Washington Post, but we believe regardless of passenger status, everyone should be allowed to wear what they want as long as they're fully dressed.

13 Czech Airlines' Baggage Fees Differ Based On Flights

Czech Airlines is the flag carrier of the Czech Republic, but that doesn't mean that it's excellent. A traveler wrote on TripAdvisor that the first leg of the flight had no baggage fees, but the second leg had extremely high baggage fees. So that means that the baggage fees depend on the flight, which basically means that travelers must have a lot of money before boarding its flights.

12 Kuwait Airways Prohibits Alcohol On Its Flights

The TSA allows passengers to bring alcohol on airplanes as long as it's stored in a 3.4-ounce bottle or purchased at a duty-free shop, but not Kuwait Airways, which doesn't allow its passengers to carry or consume it on board. This shouldn't come as a surprise as Middle Eastern countries are more conservative, but still, it's super strict for the rest of us.

11 JetBlue Airlines Charges Extra Fees On Surfboards

While most airlines take a direct approach to its baggage fees, JetBlue Airlines is a bit harsh towards its passengers, mainly those who are unaware of their rules. For example, the rule where surfboards, windsurf boards and kitesurf boards weighing over 100 lbs won't be allowed as checked baggage on its domestic flights. That's a bit unnerving for the surfers out there.

10 Emirates May Not Allow Food On Board

Emirates has been ranked one of the top airlines in the world and that's a no-brainer, but I saw on TripAdvisor that you may not be allowed to bring food on an Emirates flight. But per The Independenttheir Cajun chicken sandwich is lackluster, which makes it seem like they want you to eat their food so it doesn't go to waste.

9 El Al Airlines Charges Fees To Transport Bikes Regardless Of Size

El Al Airlines has been dubbed as Israel's national airline due to its customer service, in-flight entertainment, and non-stop flights. However, a TripAdvisor member vented about how El Al transported his bike for free, but later changed their rules to charge a fee even if it weighs less than 50 pounds. That seems a bit pricey.

8 Korean Air Requires A Doctor's Note On Prescriptions

Korean Air provides its passengers with some of the best deals, food, and seats available. Though Korea can be a strict country with excess rules and Korean Air is not an exception. Its passengers can bring prescription medication on board, but customs can check the containers and ask for a doctor's note.

Related: 12 Coronavirus Myths Travelers Believe (That Just Aren't True)

7 Ethiopian Airlines Demands An Exit Ticket Even With A Passport

Ethiopian Airlines is infamous for its 2019 Boeing 737 MAX 8 crash, but it's also known for its unfair rules, according to a TripAdvisor member who wrote about how she had a one-way ticket from Cape Town, South Africa to Rome, Italy and used her US passport, but wasn't allowed to board unless she purchased an exit ticket. That's not cool.

6 Spirit Airlines Charges A Fee If Your Carry-On Has To Fit In The Overhead Bin

Spirit Airlines is a low-cost carrier, but it's not the greatest carrier out there. Spirit can be really strict in terms of baggage rules. A FlyerTalk member wrote that if the carry-on bag can fit under your seat, you don't have to pay, but if it has to go in the overhead bin, they'll charge you between $26 to $55.

Related: 20 Photos Taken By Passengers Aboard Spirit Airlines

5 Air Canada Gift Cards Are Useless

This rule may not apply to each flight, but it's still mind-boggling nevertheless. A traveler expressed her frustration on FlyerTalk writing, "I had a phone agent at the SE desk refuse to accept an AC gift card a couple of days ago. I was trying to pay a change fee and was informed gift cards can't be used to pay fees." Wow, just wow!

4 British Airways Asks Passengers To Turn On Their Electronics

British Airways is rather authoritarian in its electronic rules. You see, the airport security staff may ask you to turn on your electronic and/or battery-powered devices to show them that they can function or else they won't let you take them with you. Also, uncharged devices have to be in your checked bags.

3 Choosing Seats Doesn't Apply on American Airlines Flights

American Airlines is far from a low-cost carrier, but it still has many issues to address in order to go above and beyond. A traveler reported on TripAdvisor about their seating policy calling it "terrible" and claiming that American takes the no choosing seats rule one step further by seating people who are traveling together apart unless if you upgrade to a paid option.

Related: 10 Airlines With A First-Class Experience Worth Every Penny (5 Not Worth Considering)

2 Aeroflot Bans Umbrellas On Its Flights

Aeroflot is Russia's flagship carrier, but they can be a tad bit strict when it comes to its cabin baggage rules. According to a traveler on TripAdvisor, Aeroflot changed its rules in February 2018 and stopped allowing cameras, notebooks, phones, phone chargers and umbrellas in cabin baggage. Now they're only permitted in checked baggage.

1 Water Isn't Allowed On Volaris Flights

Volaris is an ultra-low-cost carrier based in Mexico City, Mexico. Volaris is a great deal for those who want to fly to Mexico and Central America, however, the low fares come with inconveniences. Volaris and most, if not all, Mexican carriers don't allow water bottles to be brought on board even if they've been purchased after the security checkpoint.

Next: 10 Airlines That Treat Their Customers Poorly (10 That Treat Them All Like First Class)