As startling as the claim in the title to this post may seem, I know it to be true. For you see, I was that skeptic. This is how it happened. I had to fly from Brisbane to Sydney and back again a few weeks ago. I boarded the aircraft, but I took no notice of its particular configuration, distinctive features etc. To compound my error, I also took no notice of the emergency spiel from the flight attendants, and did not (as instructed) take out the laminated card from the seat pocket to help me locate the emergency exits (the laminated card also always identifies the aircraft).
So I flew in the aircraft, but I did not know (or care) what kind of aircraft it was. So for me, it was, and remains, an Unidentified Flying Object (UFO).
While flying, I did notice some of the passengers talking in languages other than English. Further, some other passengers, while talking in English, were doing so in non-Australian accents. The chances are very good therefore, that some of my fellow-travellers were aliens (i.e. belonging to a foreign country - OED).
So, I literally, and verifiably travelled with aliens in a UFO. But I couldn't interest the newspapers in my story. Go figure.
Tagged - UFO, Alien, Skepticism.