Intersection Departures

[Slipped_Surly_Blonde]

Heres a quick question for all those in the know regarding wake turbulence and intersection depatures....

For a medium aircraft departing from a runway intersection behind a heavy using the full length, is the time delay always three minutes or does it depend on how far the intersection is from the end of the runway??

If so how far does the interesction have to be inset before it is deemed an intersection and whereis it written?

i.e. using H/G on 08L or B/C on 26L at LGW.

Couldn't find it in any of the manuals on the flight deck .... you guessed - another long sector!!

Cheers!

SSB