Save Your Money
Make sure you save the money you earn in the game as Project Wingman gives you access to progressively better planes as you progress throughout the campaign. Initially you will be given T-21 and T/F-4 trainer planes, and they will suffice for the first few missions. After that you will need to invest in a better plane which you will be able to afford. It is not until you reach Mission 8-9 that the planes start to become really expensive, so it is recommended that you try and save up as much cash as possible for when planes such as the F/S-15 and SK.37 become available for purchase as they will make the later missions in the game easier.