I believe DOG misread your question... Passanha was asking which mode is the default setting for the ESC in the heli.
I was unable to find an answer just reading the various manuals for the heli or the individual parts ( Heli, ESC or Flight controller ). So I'd ask Align support in an email if no one else comes in with a direct answer. The following is also not to give a direct answer...
Most ESC's are by default set to linear ( Align refers to this as Airplane mode ). There are two 300X models, one is the Combo and one is the RTF. I would assume Align would have already setup their recommended setting for the ESC for the RTF but that is a guess and I don't know if that would apply to the Combo or not. So if you do contact Align support, mention that you got the Combo or the RTF so they also know. I can say this ESC has 3 modes, the Airplane ( linear ), Helicopter 1 and Helicopter 2. The manuals that I skimmed through were not clear as to the differences and as I said, didn't list the defaults in any case ( unless I missed them ).
There are programming utils / accessories like the ASBOX which are mentioned. I also saw mentioned the Flight Controller ( MiniGRS ? ) can be setup using a smartphone but was unable to find more information on that. The ASBOX is used to configure various ESC's and also can be used to update firmwares but again the info was not very informative on how to use it and only listed a few models of ESC's that it works with despite it being mentioned in the 300X's manuals.
If you haven't already tried searching for Youtube video's on setting up the 300X that you got... do that, no doubt some good info would be found there also.