SUMMARY OF INFORMATION TO JAS THE B737 PILOT reports that he was over the Pennines, about 8 or 9 NM SE of Manchester Airport, at 4000ft, while being radar vectored by Manchester radar on 119.4. He was flying at 180-210 kt on a N heading and squaking 5734 with Mode C selected. Although it was dark, visibility was over 10 km with a fairly strong NW wind (340/30). While flying just above the tops of some rugged Cu both he and the first officer saw a lighted (see JAS notes) object fly down the RH side of the ac at a high speed from the opposite direction. He was able to track the object through the RH windscreen and side window, having it is sight for a total of about 2 seconds. There was no apparent sound or wake. The first officer instinctively 'ducked' as it went by.
Manchester - 'Well, there's nothing seen on radar. Was it er an ac?'
B737 - 'Well, it had lights, it went down the starboard side very quick.'
Manchester - 'And above you?'
B737 - 'er, just slightly above us, year.'
Manchester - 'Keep an eye out for something, er, I can't see anything at all at the moment so, er, must have,
er, been very fast or gone down very quickly after it passed you I think.'
B737 - 'OK. Well, there you go!'
Pilot sketch of the object: