737 leading edge.
 

I was boarding a 737 the other day and I noticed circular holes on the underside of the leading edge of the wing. One of the other passengers standing beside me said they were for air to pass through. Is that true?

Sounds like vents for the wing leading edge anti-ice system (I think the 737 uses a bleed air system). So, yes, I think your fellow pax was correct.

Spot on!

Cheers :ok:

Yes, of course you are correct.

There are two groups of three holes on each leading edge, as you say, for the anti-ice bleed air to escape.
On the NGs the outboard leading edge each side is not anti-iced, so therefore there are no holes under the outboard LEs.

Just to sum up,

Chers, FD :D

http://www.b737.org.uk/le_slat.jpg
A prize to the person who can spot if this is a Classic or an NG.

Too clean for a Classic:)

Too much paint remaining for a New-Gen!:)

Inboard LE NG.

Now where's me Newcastle ? :}

Gerorf - its mine:)

Inboard LE NG.
And the ptoto is taken at stand B2 in EKCH.
Now where's me Newcastle? :8