What is the function of zip cords installed around some panels?

The function of zip cords installed around some panels is primarily to aid in gap filler removal. These cords assist maintenance personnel in easily accessing and removing the gap fillers during routine maintenance or repairs. Gap fillers are typically used to cover seams and joints in low observable aircraft to prevent radar waves from bouncing off these areas, and having a method to efficiently remove them is vital for both maintenance and ensuring that the surface remains as low observable as possible.

The design of zip cords allows for a quick release, reducing the time and effort needed to remove the gap filler while minimizing potential damage to both the filler and the surrounding surfaces. This is particularly important in maintaining the stealth characteristics of the aircraft.