When you pull on the yoke to increase pitch, you’re actually dumping lift*. Yes, it is at the tail which means you will also set up a rotation. Yes, this rotation will eventually mean a larger AoA and more lift. Yes, this will – eventually – reduce the rate of descent.
But right now you are dumping lift.
That is just as if you were extending spoilers. Less pronounced, but the same thing, and just when the main problem that you are trying to sort out is that you should have flared (more) a few seconds earlier to have that small extra amount of lift.
Yes, technically that is precisely what you are doing. I think the discussion here is around
how much lift are you actually getting rid of, or to simplify, what is the change in the force applied?
Ground spoiler deployment pretty much destroys the lift over a large percentage of the wing. I would not be at all surprised to hear that it was somewhere between 25% to 50% less than a 'clean' wing. (Any experts care to comment?) That means up to half of the weight of the aircraft is now trying to accelerate it downwards.
The tailplane is a 'trimming' device. It doesn't generate anywhere near the forces the the mainplane does, nor can it. In cruising flight in a well loaded aircraft, it may not be producing any lift at all!
The aircraft (mass
m) is approaching the ground at velocity
v. To reduce the vertical component of
v you must apply a force
F over a time
t. You have a choice of applying a large
F over a small
t or vice-versa. As we are close to the ground,
t is, unfortunately, destined to remain rather small. So we need as large an
F as possible in order to have an
appreciable effect on
v. Yes?
You are just not going to get enough force from the tailplane to have much effect on the momentum of the aircraft. If somehow you did, the primary effect would be to somersault the aircraft over it's nose or to do a complete back flip. It's about moment arms and inertia.
I think you need a lot more than a 'small amount of extra lift' to reduce a high rate of descent, and the
only place that is coming from is the wings themselves with a higher AoA.