Thanks
Broadreach. Considering I did my own 707 base-training with AA at DFW, I was a bit slow on that one!
But, by then, the JT3D (turbofans) were producing a lot less smoke than the stove-pipes in that photo.
Quote from
PAXboy:
"...it was the action of Gear Up - that
produced the Positive Rate of Climb."
On a more serious note, that's unlikely. The opening of the gear doors adds so much drag that - as a general rule - it will take even longer to reach screen height, because maintaining V2 (or whatever) will require a lower pitch angle. So selecting the gear up is not going to get you over the perimeter wall: the benefit will be delayed until retraction is almost completed.
By the way, even the 707-320C (with the turbofans) could struggle out of LAX on a hot day at MTOW. Passing Vr, you couldn't afford to rotate too enthusiastically (as I once did) or the a/c could sit on the runway.