Bleaklow: low flying jets

I have been used to low flying military aircraft but under the flight path to Ringway you get passenger planes low over the hills. I think the wingspan of this one is 80m. If my finger subtends 1 degree, the 80m is worth about 2 degrees. In radians that is 0.035 radians. Small angle in radians = arc length/radius. Here radius means height of plane so 0.035 = 80/height. Height above me = 2285 metres. That sounds far too big. I thought it seemed quite low. Even if my finger was only 50cm from the camera the height stubbornly refuses to come much below 2km.