Two subjects mix here: one is law, the other's marketing.
In legal terms, such an ad would suggest a law firm specializing in the law of torts, in Federal aviation laws and in suing according to the (now revised) Warsaw convention. Luckily, commercial airliners' crashes are not very common, so hopefully related lawsuits would be rare. Not only that, but the Warsaw convention - which is relevant to all int'l flights - protects the airline by setting a limit to all lawsuits. Therefore, you will not find a multi-million dollar lawsuit when a plane - god forbid - crashes, unless there has been serious negligence on behalf of the airline (a good example is Pan Am, that went bankrupt following a lawsuit that broke the convention's barriers).
Having said all that, we should analyze the matter from a marketing point of view. IMHO, the ad was there to be heard by people who'll remember the law firm whenever an aviation related dispute arises. There are millions of lawsuits against airlines every second. Wherever there's a lawsuit, there are lawyers and there's money for lawyers to make. By exposing your audience to the fact that the you deals with airline crash related lawsuit, you make sure the listeners know you're serious and professional. I guess those are some of the thoughts behind that ad.