Expert: Matthew Smith - 6/10/2009

Question
TOPIC: Legality and Ramifications of side-stepping ridiculous fare structures by interrupting a multi-city flight itinerary to get off the plane where my car is parked.
BACKGROUND:  Live in Philly.  Needed to fly PHL to DTW on short notice.  Main PHL carrier wanted $400 each way for 2-day advance fare, or $143 each way for 14-day advance.  So, I tried BWI.  Same carrier, due to competition from Southwest, offered 2-day advance of $143 each for for BWI-DTW VIA PHL.  So, I booked flight, drove to Philly's 30th street station, parked, took Amtrak to BWI, took flight from BWI to PHL to DTW, and intend to return from DTW to PHL, but will EXIT the plane in PHL to pick up car at 30th Street Station.
QUESTIONS:  1) Is this "illegal"?  I doubt it, but I am SURE the airline doesn't approve of this method for "beating their fare structures."  2) Can airline "come after me" for getting off a plane in the middle of the itinerary?  3) I know you can't "get on" the plane in the middle of the itinerary, because they will CANCEL the reservation if you don't start in the origination city, but WHAT CAN THEY DO if you get OFF on the 3rd leg of a 4 leg itinerary?  4) Can they "blacklist you" for doing this to beat their fares?  5) Can/will they report you to the TSA or other authorities?  6) Can/will they follow up with you to find out "what happened to you" when you started on on Leg 3, but never finished Leg 4?

BTW, this convoluted reservation scheme saved me nearly $500, and taking AMTRAK to BWI from Philly was quite pleasant.  I'll do it again, provided your answers don't tell me that I am headed for a confrontation.  BWI is ALWAYS cheaper than PHL due to LOTS of competition at BWI.

Please ADVISE.

Answer
Rick, I cannot offer any legal advice and what I say here MUST not be construed as such.

1) Technically you are breaking a contract of carriage with the airline.  I suppose the airline could possibly file a civil suit against you if they noticed that you are trying to cheat their pricing system.
2) I have never heard of an airline coming after a person who skipped a leg of an itinerary.  
3) As you noted, skipping a leg on an out-bound flight can cause serious problems like having your entire reservation canceled, but if it's the last leg of a return, then it's difficult to see what they could do.
4) I've never heard of a blacklist of passengers for this kind of activity, although that doesn't mean one doesn't exist.  I think that one would have to do it all the time in order for anyone to even notice it.  That's an interesting one I'll have to ask a friend who is still in the Yield and Tariff Management business.
5) Skipping a leg is outside of the TSA's scope of work.  Just make sure you don't have any bottles more than 3.4 ounces.  ;)
6) Probably only if someone were to call them looking for you.

I cannot recommend doing this all the time, although I see why you would want to. (Who wouldn't want to save that kind of money?)  To keep it perfectly legal, you can just drive to BWI each flight and park there.  I haven't been to BWI in ages.  It seemed like a nice enough airport, whereas PHL is perhaps my least favorite airport.

Oh...if you check a bag, it will go all the way to BWI, so you need to do only carry-on.

Hope this has helped, and I also hope that you can understand why I am being non-committal.  I simply cannot advise anyone to do this because I know it is against the contract of carriage and I do not want to have some reader sue me for doing so.