B737-800 roof antenna?

[1900]

Hi all,

Please could somebody answer this...the large,raised white antenna that is found on the roof of all the 737-800s I've seen, approximately in line with the 2nd row of windows, seems to come in two shapes-a raised seemingly ROUND one on some a/c, and a raised seemingly RECTANGULAR shape on others...first, please could someone tell me what antenna this is, and secondly, are there two types, or just the one that seems to look different on different -800s?

Thanks!

190

[SeldomFixit]

Guessing upper TCAS antenna

[enginair]

737-800 roof antenna

I am only in GA but take an interest in the airliners I thought that antenna was for the entertainment system is live tv

[Nightrider]

1900, you may want to look at this

[LME (GOD)]

If it's about the size of a wheelie bin lid, then it's probably the SATCOM antenna

[SeldomFixit]

What did I win ?