Sitting in my garden, I saw a plane passing by with quite a big contrail. As a spotter I look at every plane passing by and knew this did not look normal. I got my binoculars and took a look at it. It was a 2-engine British Airways plane(I am a military spotter and did not know the type) which I thought to be a triple 7. The contrails were not coming of the engines, but somewhere between the engines and the tip of the wing. In al my life I have not seen anything like this.
Does somebody knows what this is? And why it happens?
See attached picture, which I took with a small pocket camera, so I apologize for the poor quality.
![Image](http://i1031.photobucket.com/albums/y375/gurbs2002/IMG_5757.jpg)
thnx,
Gerben