The 170A is a pre test test, basically it makes sure you are up to standard for the test real so you are not wasting the time of all those involved by not being up to standard.
There are two CAA standards documents which refer, you should look at the IR(H) and 170 A
This is the full link of l standards documents including the CPL(H)
http://www.caa.co.uk/application.asp...e=sercat&id=22
This is the standards document for the 170A
http://www.caa.co.uk/docs/33/SRG_FCL_06_H.PDF
This is the IR(H) Initial standards document
http://www.caa.co.uk/docs/33/srg_fcl...licopters).pdf
They are a flight and not a theory test