737 Inboard/outboard anti-skid
 

Hello guys,

I just want to make. one thing clear in my mind that in the situation of "Loss of both engine driven generators", we stay with only standby Electrical Power and in that case, AFM states only INBOARD ANTI-SKID SYSTEM will be operative.

To my understanding, it means two of four -number 2 & 3- tire skid system will be working. Is that correct?

If it is so, what's the logic behind it?
Anyone has information about that, appreciate to lighten me up.
Thanks in advance

That is correct. As to the logic behind it, I can only assume that Boeing made a decision way back that having antiskid operable on two wheels is better than on none at all, and the engineers designing the standby electrical system had a few amps to spare...

System isolation - the inboard and outboard anti-skid have different systems - that way if one fails you still have some anti-skid and it's symmetric. With complete loss of all power generation you go to the battery which is obviously load limited. So only one anti-skid system gets powered (and as STBYRUD notes, one is better than none). There are many 'redundant' systems were only one gets powered by the battery (e.g. Air Data/ADIRU).

Thanks guys for the help, now it's more clear.