No. You misunderstood.,
EGBB
This airport required a minimum climb gradient of 4.5% . All the sids are either that gradient or higher.
Looking at the topography, the airport is surrounded by flat land. Therefore, I am assuming the required climb gradient is for noise abatement. Maybe some towers around the airport area...
If I can't meet that gradient with 1 engine (Departing full of fuel for a long haul flight), does that really restrict me to depart from that airport? There is no ODP on the airport chart.. So, I am in a loss here...
Thanks