On June 23, more than 1500 international passengers will move through Queenstown Airport in the space of three hours as the 2012 winter season moves into full gear.
However, airport operations will be pushed to their limits in August when 12 international flights and 30 domestic flights arrive on the same day.
Ten international flights will land on June 23, coinciding with the first full day of Queenstown Winter Festival activity.
Queenstown Airport chief executive Scott Paterson said the international arrivals and departures hall was still being upgraded and the full benefits of that investment would not be realised until next year.
"Ideally, we would have started the build last year. We started in February this year, but it wasn't possible, given all the work ahead, of bringing those things on line.
"There were some delays in the steel getting here, but we're still targeting July to open up, or re-open [the] areas," Mr Paterson said.
Logistically, the busy winter season, peaking about August, would pose some problems.
Airport officials, carriers and agencies would meet regularly.
"If everyone arrives on time and leaves on time, it's going to be tight, but it's not that difficult.
"The challenges are when things go off schedule - and in winter, things go off schedule.
"It's not an if, it's a when.
"There's this apprehension out there at the moment, mixed with excitement.
"The apprehension is that it's going to be really busy ... and stressful, and there's excitement because there is going to be a lot of people here, which is great for Queenstown."
At Queenstown Airport last month total passenger numbers grew 11.6% on the same period last year.
A total of 59,567 domestic passengers moved through Queenstown Airport to the end of May, and 6398 international passengers took that total to 65,965 for the year to date, up from 59,111 to May 2011.
Growth was driven by domestic passenger numbers, up 13.6% for the period.
Driving the increased numbers were Jetstar's Queenstown-Wellington daily service and Air New Zealand's increased operation of its larger capacity A320.
