Travelers boarded around 5% more flights this year than in 2009, and close to 7% more than in 2008 – good news for the airline industry, yet they don’t seem to be welcoming customers back with open arms.

In Zagat’s 2010 airline survey of over 8,000 frequent travelers taking 139,300 flights, the overarching message was one of dissatisfaction. Travelers feel they’re being squeezed – both financially and physically – by burgeoning ancillary fees and “cattle car” like flying experience; one respondent commented that a particular airline’s treatment was “a violation of the Geneva convention.” 

Here’s a handy cheat sheet if airlines want to improve their free-falling ratings of recent years:

    Avoid charging for formerly-free essential services. Ancillary revenues may be the only bright spot profit-wise for airlines, but what happens when your baggage policy drives customers away? On top of checked luggage, paying for each carry-on bag and an extra cost for larger pieces can put a bad taste in your customers’ mouths. Savvy travelers know how to avoid those pesky (and seemingly arbitrarily enforced) baggage fees: 45% of respondents avoid flying airlines charging extra for large bags, and 42% use their frequent flier status on airlines that waive the fees.

    Follow Southwest’s lead. Frequent fliers love Southwest (LUV) – although the discount carrier may fly to less convenient secondary airports, they won the Best Luggage Policy, Best Domestic Value, Best Check-In Experience, Best Consumer On-Time Estimates (Domestic) and Top Website categories. Larger airlines: time to brush up on Customer Service 101?

    Customers want self-service. 63% of frequent travelers book ticket directly on the airline’s website, while only 3% actually call the airline to purchase tickets. Make your website user-friendly and include valuable day-of-travel information like flight tracking, weather, and parking options so users can easily plan, book and manage their travel through your site.

    Convenience is just one factor. Obviously, a direct route and price are the most important factors for business travelers when choosing a flight, but airlines would do well to note that 50% of respondents cited past experience with the airline as a reason – or not – to book. It all comes back to providing a positive customer experience.

With nowhere to go but up (we hope), airlines have the opportunity to improve the travel experience by looking beyond the bottom line. Though travelers appreciate amenities like a variety of in-flight entertainment options, basic factors – such as easy access to important travel information and treating people well – will win loyalty and business.