A Bomber Stream was the enmassed aircraft of one raid that headed

towards a target on a given heading. Each aircraft flew by itself,

without the aid or assistance of any of the nearby aircraft. The steam,

which if you visualize a rectangular block would be approximately 30

miles wide by may be 20 miles deep and several miles high. Turning back

would require an aircraft to cross either in front of or though the

middle of this large formation.

Also note that there were never any fighter escorts for the bomber stream at night. What was done was the RAF sent out night intruders, mainly Mosquitos, to attack the night fighters as they took off and landed at their bases.

A Gaggle is best described as being similar the the formation that Geese

fly in. one behind the other, slightly to one side of the bird ahead of

them.