I have had several different answers to this situation:
A mariner holds a Master of Towing Western Rivers and wants to increase his scope to Inland. What are the reuirements in order to increase the scope and can you find a CFR to back that up? Thanks, Gretchen
You would have to complete the TOAR for that route, right?
…minus the common elements between the two.
The NMC just told me 90 days on that IN route and that was it!!! hard to believe thats why I am asking. I thought it was 90 days, TOAR, and a partial exam
That’s what they told you today. I’m sure they’ll have a completely different answer tomorrow.
I know, I know. I left a message with the lovely Nadine in Mandeville…she may have the answer I am looking for. I originally thought it was only 30 days of observation and training, toar, and partial…then I was told 90 days to increase the scope. I thought the 90 was only for western rivers. He already holds a Master of Towing WR…its a curious question…hopefully Mr. Cavo can give me the answers 
It should be 90 days on the route, the TOAR applicable to the route, and a limited exam.
The other option is:
<SUP>1</SUP>If you hold an endorsement as master of towing vessels you may have an endorsement-as mate (pilot) of towing vessels for a route superior to your current route [I]on which you have [B]no [/B]operating experience[/I]—placed on your MMC after passing an examination for that additional route. After you complete 90 days of experience and complete a Towing Officer’s Assessment Record on that route, we will add it to your endorsement as master of towing vessels and remove the one for mate (pilot) of towing vessels.
Which implies you can just take the partial exam and sail as Mate forever w/o ever doing the TOAR for the Master’s endorsement.