Would you volunteer to go on a cruise ship right now, even if it was free?Major cruise line Royal Caribbean is currently looking into arranging trial cruise voyages to convince regulators it can run successful Covid-era trips.And it says it's been inundated with interest from would-be cruisers keen to volunteer.If it sounds like a precarious proposition, that's because it is. The US Centers for Disease Control and Prevention, which recently lifted its ban on cruise ships operating in US waters, says in its latest guidance that "sailing during a pandemic is an inherently risky activity."But the CDC's framework for conditional sailing also stipulates cruise lines must run "simulated voyages" designed "to replicate real world onboard conditions of cruising" if they want to get permission to recommence regularly scheduled cruises.