kevin tibbles reports. >> reporter: a warehouse on wings, cargo let me ask you flight 7004, a giant 747, lumbers into chicago's o'hare airport following an over the pole flight from europe. the ground crew that has just four hours to empty this whale of an aircraft and reload it. >> especially if you have temperature controlled product you need to move the product as quickly as possible >> reporter: and it's this same system we will count on to supply the world with any future covid vaccine. the logistics of delivering it to your corner pharmacy are daunting everyone, including myself, needs a temperature check to enter dhl's massive 400,000 square foot airport warehouse, which buzzes 24/7. >> we have different zones, different temperature zones for pharmaceutica pharmaceutica pharmaceuticals. >> reporter: most vaccines require refrigeration says ben hubbard. >> if there's a break in what they call the cold chain that vaccine can lose its potency and really it's life-saving potential. >> it's a lot colder in here. >> reporter: specially designed containers can be set to maintain colder

we get more now from nbc's kevin tibbles. >> reporter: this flight, a giant 747, luvers into chicago's over the pole flight from europe. the ground crew has just four hours to empty this whale of an aircraft and reload it >> especially if you have temperature controlled products you need move the product as quickly as possible. >> reporter: it's this same system we will count on to supply the world with any future covid vaccine. the logistics of delivering it to your corner pharmacy are daunting everyone including myself needs a temperature check to enter dhl's massive 400,000-square-foot airport warehouse which buzzes 24/7. >> we have different zones, different temperature zones for pharmaceuticals. >> reporter: most vaccines require refrigeration to maintain their integrity says ben hubbard whose company monitors vaccine safety. >> if there's a break in the cold chain that vaccine can lose its potency and really life-saving potential. >> reporter: it's a lot colder in here. specially designed containers can be set to maintain colder temperatures during the flight >> extremely cold. r