I know this questions has been asked many times before. This seems to answer it. Although some may question the articles credibility. I do not find it too difficult since one of the elders in my congo used to be sent around as a CO rep and has travel internationally on behalf of the WT and he claims to have done so in first class.
http://jwsurvey.org/cedars-blog/no-expense-spared-governing-body-members-do-fly-business-class