can't seem to figure out how to make this mission work

[rocket302]

i have created a simple mission which i am trying to make a bombing run on london. i then want to add a bunch of interceptor to fight the bombers as they come in, i'm also trying to get the 109's to protect the bombers. 

here is what i have working:

1. the bombers come in and drop bombs

here is what does not work:

A. i cannot get Flak to fire at bombers when they get close.

B. i have set a p-51 to intercepter the bombers but all it does is fly around that then want to land.

i'm trying to get it to fight the bombers. 

 

i'm trying to learn this so if you look at my mission please let me know what i missed.

i've tried looking at other mission but can't figure out why they work but mine does not... so providing a different mission and saying try this has not been helpful since i can't figure it out.  any chance you can just point out my mistakes on this will be helpful

 

 

London_bliz.miz