Don't you still need metal bullets for the 3d printed gun?
The evidence is in US law. Because they would be undetectable, 3d printed guns are required to have some metal inserted into it to be legal (https://en.wikipedia.org/wiki/3D-printed_firearm#United_Stat...). I think a guy who can 3d print a gun and wants to bring it onto a plane could probably skip that step;)
Taken in a strict boolean sense, yes, but real-world policy is rarely boolean, and mostly about tradeoffs and how many nines of reliability you want to spend on.
Metal detectors will catch the vast, vast majority of guns ever produced, which is their whole point of existence.
also the rails on the lower, the barrel, etc.
That said I will note that it is generally illegal to possess such nonferrous weapons regardless of circumstance.
How does a plastic pistol open the cockpit door? It is proof to small calibers. You might shoot someone in the plane and then you will be subdued and ghaddafied with a SkyMall magazine. Not the most effective form of terrorism.
Countries that didn't create the TSA also had a reduction in terrorism.
But upthread it was suggested that metal detectors are sufficient to stop weapons and a discussion of 3D printed guns followed. Nonmetallic weapons (and other tools) of all sorts are possible, 3D printed or otherwise.