UFO sighted on SW flight out of Salt Lake Cit

Reported by Bill from c-69-140-211-17.hsd1.md.comcast.net (69.140.211.17) on Saturday, July 07, 2007 at 10:43PM :

On Friday June 22 I took off on Southwest flight 499 from Salt lake City to Portland, OR at around 6 PM. I sat on the left side of the plane.

About 10 minutes into the flight a saw A plane in the distance heading in the opposite direction. I could not take my eyes off of it because of the unusual exhaust it was leaving. Instead of a long jet exhaust, the craft was followed by a triangular shaped exhaust which was about 2 times the length of the vehicle and 3 times the height.
I watched and quickly (I mean real fast)the craft turned and was heading straight for us. It looked like a large torpedo out of water. I did not panic yet as it was so far away. Then it just disappeared.

The whole sighting lasted about one minute.

I sat by the window with my camera phone ready, but I knew I would probably never see something like that again in a lifetime.

Did anyone else see this craft? I thought about asking people but feared I'd be kicked off the plane.

Also, it may have been an experimental government plane?

Any helpful input is appreciated.