This plugin will show a health bar of the thing you hit last, somewhere on the screen.

Example:
If you hit (damage) to the Helicopter, for X seconds, a Health Bar will pop-up on the screen and show health amounth of Helicopter.
It could be done for Tank, Minihelicopter, Hot Air Balloon, Boat, RowBoat, Enemy, Animals, Bots, Building Parts etc. 

A photoshop to explain it in a better way:

wau nice idea :-) good and very cool

ya good idea

Good idea. But its performance intensive, if you wish a real-time GUI for more than ~50ppl on a server. (my own experience with that)

Not eveyone on the server will see it. Only the player who damaged it will see it for 60 seconds or until damage to something else.

Anyways - imagine 100 players see different CUIs that need to be built and sent to them from server.
I can do something for you, if you're interested. Discord: 2CHEVSKII#9066

oods are most of us dont have 100+ players active on a moded server only the very lightly modded servers have high population