This is becoming some what irretating.

Yup, there's a spot going down a ramp on the mission where you get Grunt too, I've been stuck there a few times. It's super irritating and does often require a reload, but sometimes jumping around like a loon will get you free too.

Quick save quick save quick save.

Be thankful you can quick save on the PC... The consoles didn't get that luxury until ME3.

It might be worth a try to do a manual save after the walking on air thing happens.  I'm not certain, but isn't it possible that the game will respawn you on the ground with a reload anyways; and then, at least, you wouldn't have to repeat the battle or other stuff from the point of your last quick save (but I wouldn't risk overwriting the quick save to test it).

Yeah this is an old problem with a lot of speculation on the cause, but never a clear answer that I am aware of. Besides the "krogan bridge" section on Korlus, I used to get this a lot on MSV Estevanico.

I have not had luck with saving in the air. When I load a save made after stuck, I am back in the exact same spot.

That said what I have been able to do if I had no recent save was make the save in the air anyway, then use ME2 Gibbed to edit the player position in the "Raw" tab. There is an x y and z position. The numbers may as well be giberish, but playing around with them can seem to cause you to fall to the ground.