Detective Pux here, at your service. I see you're interested in budget airline carriers in the USA. As a detective, I'm always up for solving a good mystery, and budget airlines are no exception. Let's get down to business and uncover the top 10 budget airline carriers in the USA, shall we?

First off, let me just say that budget airlines are a great way to save money on travel expenses. They often offer lower fares than traditional airlines, but you may have to sacrifice some amenities and comforts along the way. That being said, let's take a look at the top 10 budget airlines in the USA...

1. Southwest Airlines - With an estimated annual revenue of over $10 billion, Southwest Airlines is the largest budget airline carrier in the USA. Known for their friendly service, free checked bags, and unique sense of humor, Southwest has become a favorite of many budget-conscious travelers.

2. Spirit Airlines - While Spirit Airlines may not offer the most comfortable travel experience, they do offer some of the lowest fares in the industry. With an estimated annual revenue of over $3 billion, Spirit is the second largest budget airline carrier in the USA.

3. Frontier Airlines - Frontier Airlines is another budget carrier that offers low fares and minimal frills. They operate a range of flights to destinations across the USA and internationally, and reported an estimated annual revenue of over $1 billion in 2021.

4. Sun Country Airlines - Sun Country Airlines offers flights to destinations across the USA, Mexico, and the Caribbean. They have a reputation for friendly service and reasonable fares, and reported an estimated annual revenue of over $500 million in 2021.

5. JetBlue Airways - JetBlue Airways offers comfortable seats and in-flight entertainment options, along with low fares and good customer service. They operate flights to destinations across the USA and internationally, and reported an estimated annual revenue of over $1 billion in 2021.

6. Sunwing Airlines - Sunwing Airlines primarily operates flights to vacation destinations in Mexico, the Caribbean, and Central America and offers a range of travel packages. They reported an estimated annual revenue of over $500 million in 2021.

7. Viva Aerobus - Viva Aerobus is a Mexican budget airline that offers low-cost flights to destinations in Mexico and the USA. They reported an estimated annual revenue of over $400 million in 2021.

8. AirTran Airways - AirTran Airways is a subsidiary of Southwest Airlines and offers low-cost flights to destinations across the USA and the Caribbean. They reported an estimated annual revenue of over $300 million in 2021.

9. Alaska Airlines - Alaska Airlines is a major airline in the USA that offers low fares and good customer service. They operate flights to destinations across the USA and internationally and reported an estimated annual revenue of over $8 billion in 2021.

10. Allegiant Air - Allegiant Air offers low-cost flights to destinations across the USA, primarily to vacation destinations. They reported an estimated annual revenue of over $1 billion in 2021.

I hope this list is helpful in your search for budget-friendly travel options in the USA. And remember, if you need any further assistance or a good laugh, Detective Pux is always here to help!