lightning?

Do you mean in real life or in the sim?

Because they are not grounded. They have to have a place for the electricity to flow through in order to be hit.

My girlfriend is an air hostess and a couple of years ago she was on a flight form the UK to Portugal. Just airborne form NCL they got struck by lightning, no major problem but she was sitting blow where it was hit (front end) in the forward galley and could smell burning. Reported to the Capt who opted to return. After inspection the smell had been the burning of the paint there was something like 13 pin prick holes with scorch marks in that area alone. Exit point which is where the damage is generally found was via the tail but no major damage. It possibly does happen in the sim, not always noticeable even for real until you land and see a big scorch mark!

In real life, if a plane is struck by lightning, there is a rod near the middle of the plane that dissipates the energy to the back of the plane and out into the air.

I have read somewhere that on average a commercial jet will be struck 10 times per year
There was a video showing a 747 being struck shortly after takeoff(and Ive searched and searched for it with no luck...............yet)
I have found this article which has 2 photos at the bottom of page 2 (it opens as a PDF file,so give it a little while to load)➡

Im off to find that video

The reason the lightining doesnt kill everyone is not because it isnt grounded or earthed its because of the shape of the plane the shell of the plane deflects the electricity around the interior just like cars.