Departure weight, say 385 tonnes at TOC F300 .. single engine .. dumping fuel, driftdown altitude probably about 5,000ft, maybe a bit less. Return for ILS 7L. Tricky, but doable. Would also depend on whether you have an inner or outer engine as your plaything.
Depending on where you lose the engines on departure, 2 engines is doable. At 397 tonnes, you'd probably want to be 1,000 ft just starting flap retraction (you might even get away with it a bit earlier). Daylight is a big factor if you want to use ground effect.
You wouldn't want any obstacles, they stuff you right up.
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