Totally depends on what kind of voltage drop you will tolerate, and what load you will have to create the voltage drop.
A 50 amp RV has 240 volt supply but I have never seen one that supplies any 240 volt equipment. Generally they have more than one A/C but they are 120 volt units on opposite lines of the 240 so those will balance out, but most other load could easily end up being mostly on one side or the other in some cases, just something to consider. If you used a cheater to plug this into a 30 amp circuit - both AC units will run but there is no extra capacity to run much of anything else at all.