Black circles on BA 737s

[splonguk]

I do know what they are, but can't remember exact.

What exactly do the black circles on the nose cones of some BA 737s mean. I know it shows that they are fitted with some new system which is currently being tested by BA, but what system is it?

See the link below for example:

http://www.airliners.net/open.file?id=161056

Cheers

[Lucifer]

MLS: microwave landing system

[This message has been edited by Lucifer (edited 19 May 2001).]

[splonguk]

Sorry but MLS means???

Sorry - not quite up on all my aviation abbreviations!

[stagger]

Microwave landing system?