fly + haste + heavy armor = ???

[KarinsDad]

But, the maxium is for the "normal speed." So, max is +30. 20+30 = 50 Speed.

The normal speed encumbered is 20, not 30.

It all depends on interpretation (since it is not crystal clear).

 

[ThirdWizard]

After looking through the SRD it does look like normal speed refers to current or modified speed. I have to wonder why they chose the word "normal" to mean "modified" though. It is very counter-intuitive. Also it looks like they sometimes use "normal speed" and "speed" interchangably, only confounding clarity.