The plane is starting from a much higher height than the bridge jumper. I think the plane altitude was 400 feet or so at the point of impact. The Golden Gate Bridge is 220 feet. You do get some of the parachute not opening cases where the person survives, but I would think the extra 180 feet is significant (even if the forward momentum is canceled out)
More to the point, I am not aware of anyone ever surviving a plane crash when the plane has fallen straight down. When the plane crashes at an angle to the ground it can absorb some of the impact. Are you aware of any plane crashes where anyone survived impact from a straight vertical fall of 400 feet?
1. I don't know. I don't follow plane crashes. I do vaguely recall instances where a handful of people survived crashes that killed everyone else, but I couldn't tell you anything about them.
2. Yes, the additional altitude would likely be significant, though not necessarily. It would depend on the terminal velocity. I don't know the terminal velocity of a human body in the air. For a plane, it would depend greatly on the shape of the fusilage after explosion.
3. This plane almost certainly did not fall straight down. There would be no force strong enough to change its horizontal velocity to zero. I doubt it has any significance, though. In fact, my instinct would be that you'd have a better chance of surviving a crash at a vertical velocity X if the plane landed nose-first and fully vertical, than one where the plane is more horizontal. There would be more crumpling along the axis of the body, I would think.
You might be confusing two different concepts. Maybe not. When a plane comes in at an angle, less of its velocity will be in the vertical plane. So if you have a plane going 150 mph and impacting at a 30 degree angle, only 75 mph of that speed is going to be vertical. Assuming it's not running into the ground and a mountain at the same time, we can safely disregard (or at least de-emphasize) the horizontal velocity. And so it's a comparison of 75 mph versus 150 mph if the plane's velocity is fully vertical.
Now, if we assume that there are no wings, then the vertical velocity will primarily be a function of the height of falling. If a plane at 0 mph falls from 400 feet, its vertical velocity would be the same as one that is moving 200 mph horizontally, at least to a first approximation. But air resistance could play a role. Air resistance is usually modeled as a force proportional to the speed of an object (not the velocity). So a plane with horizontal velocity could reach its terminal velocity more quickly than one with no horizontal velocity. And if so, it could mean that the terminal velocity will be smaller in the vertical plane than the plane falling straight down. But there are a lot of factors that would influence that, and it's beyond my ability to evaluate them.
