Planning a trip this summer? You may want to walk. Drive. Boat. Take a train. ANYthing but fly.

So far this summer air travel has pretty much been a recipe for disaster. Crashes are up, service is down. (Don’t believe me on that last? Check USA Today’s passenger ratings, or JD Power & Associates’ 2007 North American Airline Satisfaction Study.) I know that once-glamorous airlines have become the steerage version of a Greyhound bus, but this week air travel’s woes seem to be reaching new heights.

Yesterday a computer blew at United Airlines, paralyzing its flights for several hours and causing schedule delays for thousands of travelers that will likely reverberate for a couple more days.

Then there are the poor passengers on Continental Flight 71 who spent the hours between Amsterdam and Newark literally sitting in sewage when the toilets overflowed. It seemed someone stuffed latex gloves down the john, and for the next seven hours more than 200 passengers fumed (or were fumed, take your pick) while the flight attendants asked them to wait until the plane landed.

The problem started early; Flight 71 detoured to Shannon in Ireland to fix it once, the effort was deemed successful and the flight allowed to proceed. Oops.

Continental, by the way, is the highest-ranked airlines in JD Power’s study.

Jeez. What gives?