Role of Winglets in Lightning Attachment to Aircraft

Abstract:
Lightning has been a serious electromagnetic threat for aircrafts. One of the first steps towards designing an efficient lightning protection system would be to identify the possible attachment points where lightning can strike the aircraft. The most common mode of attachment to the aircraft, known as the aircraft-initiated mode, is caused by aircraft-initiated bipolar leaders. Previous research has indicated that aircraft components, such as the nosecone, wingtips, and vertical stabilizer tips, play a crucial role in the initiation of connecting leaders. Today, all modern day aircrafts come with winglets. Winglets are aerodynamic bent of aircraft wing tips. The normal wing tips are usually not active in the cruising position, but the same may not be true with winglets. Hence, in the present work, an assessment of the possible role of winglets in lightning attachment to aircraft is taken up. It is found that in the normal cruising mode, unlike the tips of the regular wings, the winglets can also be the initiation points for upward discharge.