Believe it or not, some of the early types (B707-120 for example), simply could not meet the fifty foot requirement anticipated, performance-wise, so the screen height was lowered to 35 feet.
Some of those early models were...lead sleds, in the extreme.
Yes, that was the reason for the lowering to 35 feet.
I can recall quite a few accidents in the KC-135 caused by the failure of the water injection system. One of the worse was in Wichita, Kansas. They lost water injection right at rotation, they immediately started dumping fuel out of the refueling probe, but to no avail. The aircraft crashed and the flames from the resulting crash followed the stream of dumped fuel and caused a lot of homes to be burned down causing the deaths of a lot of people on the ground. A total of 30 people were killed, the seven crew members and twenty three people on the ground.
City of Wichita - 11 - The Reawakening 1965