2 Improved the quality of the title of this post (http://meta.aviation.stackexchange.com/q/1485/19)
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Braking Contributions What are the relative braking contributions from Wheel Brakes / Spoilers / Reverse Thrustwheel brakes, spoilers and thrust reversers?

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Braking Contributions from Wheel Brakes / Spoilers / Reverse Thrust

What is the relative contribution to braking forces in a typical large commercial aircraft from the three different devices contributing to braking after touchdown:

  1. Wheel brakes
  2. Speed brakes / Spoilers
  3. Reverse Thrusters

The relative contribution should change with velocity so even nicer if we have the velocity depended thrust contributions. e.g. Reverse Thrusters provide more braking at the initial high velocity part of the roll out.

I'm posting a illustrative (but totally made-up) graph to clarify for what I was looking for:

enter image description here

I am looking for either empirical data or theoretical predictions for the thrust. Qualitatively I'd expect the spoiler contribution to fall off with a square law dependence on velocity. I'd think the reverse thrust offers a somewhat constant component but perhaps higher initially due to parasitic drag by the clamshells? Not sure, and this is what I'm trying to get: A quantitative relationship.

In case the answer will vary hugely depending on aircraft, I'm open to any specific case being illustrated.

Let's use the limiting case of full brakes with anti skid on.

PS. Since spoilers directly add to drag as well as indirectly help braking by dumping lift teasing out their braking thrust contribution might be harder?