If you're flying on the equivalent of a friends/family ticket (discounted but standby), you may not clear the standby list until the flight is about to leave. We had one with Delta, and went to Hawaii form Washington, DC. You will, of course, have to get a visa ahead of time and hope you get on the flight (you'd be at the lowest of the standby lists). Doubt a travel agent will work up an itinerary for you since you won't buy the ticket through them. Ask the consulate or embassy, as suggested, or ask US Airways. Remember, your flight back will also be on standby. Will you get a hotel room just upon arrival? I hope this isn't for during Carnaval of the World Cup.