what TSA considers a "light jacket"
 

One layer?
Not very thick?
Not containing down?
Not worn by an attractive person?

Best guess, Screener Discretion.

From personal experience, I can tell you that I've never been asked to take off sportcoats, suit jackets or windbreakers when going through PreCheck or PreCheck Light lanes.

Which is pretty much the only answer to any question involving TSA policies.

which is why I stuff my jacket in my carryon. One less thing for them to get fixated on.

In my experience, a denim jacket/windbreaker has been fine. As a matter of fact, a screener waived me along in a denim jacket with lots of metal buttons . . . crickets from the machine. If it's suitable for wearing while shoveling snow, take it off.

No idea what that means, as I have never done that

Brilliant choice, let the. stupidest use their "discretion"

That's the TSA WAY©!

After being stationed in Maine wife said we would go south until people couldn't identify a snow shovel. Ended up south of San Antonio.

There are enough snow birds south of San Antonio to tell you the make and model of the snow shovel. :D



I have seen an attractive women asked to remove a very thin sweater as the TSA agents gathered for a better view to gawk. There is no rhyme or reason to the TSA agent's interpretation of the rules. I have had to hand a printed copy of the TSA rules concerning scissors when I had a wound to redress. The safety scissors were less than 2" in length which is under the listed 4".

+1.

I flew with a jacket where I was unsure whether it would be considered "light" or not. It could be considered either light or medium depending on whom you asked. I asked the TSA person running the BP scanner if my jacket would be considered light and she said that was a good question and if she were doing the screening she would consider it light which I took to mean that it was in the grey area between light and medium and someone else might have a different opinion and it is up to the screener to decide. I took my jacket off to avoid any potential issues.

I've walked through with fleece jackets and down vests before.

Typically I put my jacket and anything in my pockets in my carryon just to avoid any hassles.

I've had to take an unlined windbreaker off. After that, I just started stripping to my base layer and stuffing everything in my bag before I approach the TDC. Aside from the risk of drawing unwanted attention, I really don't like putting my clothing, even outwear, in the bins.

It's a minor hassle that I shouldn't have to engage in, but at least I never travel in business attire, so I'm not messing up a suit jacket by stuffing it in my bag.