Mission 47 is one of the repeated missions. Its goals are identical as the ones from mission 21. All of the details can be found in the description of it. The biggest change is the fact that the Big Boss cannot be spotted by the enemies. If he is, you fail the mission. This however doesn't apply to his sidekicks. Two more changes involve forbidding the usage of Reflex Mode and Chicken Hat.
It is the best to do this mission during the night-time. It will be easier for you to hide whilst on the airport. Make D-Dog your sidekick as he is able to tag and attack enemies without raising the alarm and, thus failing the mission.
If completing the main objective is all you want to do, you can bring a sniper rifle with yourself. In any other case, take a rocket launcher which will be vital for shooting down the chopper with a VIP and a plan inside of it. Make sure that your rocket launcher is powerful so it can neutralize the chopper in one hit. Whether you want to shoot down the chopper or not, equip yourself with a best version of the Sneaking Suit.
The main objectives of Orders The War Economy stay intact. All of the minor changes are listed below.
Infiltrate Nova Braga Airport the same way as you did the first time you were doing this mission. Get to the gate in the northern-western area of the airport and wait until there are no enemies around, as soon as this happens, open it. Head to the main building.
If you want to end this mission with an S rank, sneak into the room ion the first floor immediately and kill the gun seller. Even though it isn't your main target per se, it will unable your main enemy to hold a meeting. Then you will be left with leaving the area.
However, if you want to complete more objectives, you will have to carefully get rid of each enemy before the chopper arrives. Here again, if you want to shoot down the chopper, you will have to be equipped with a powerful rocket launcher.