What are these lines on the nose of the aircraft ?
Radomes are large dome-shaped structures which protect the radars from the bad weather conditions but at the same time allow the electromagnetic signals to be received by the radar without any distortion .
These are called Lightning Diversion Strips or Lightning Diverter Strips.
Since radomes are generally built with composites, they do not transmit static electricity in the same way that aluminum skin would.
Construction of Radome -:
the radome is constructed of fiberglass and is provided with lightning diverter strips on the outside surface.It further states that these diverter strips are constructed of thin gauge aluminum.
The radome (RAdar DOME) is an aerodynamic fairing that houses the weather radar and ILS localiser and glide slope antennas.Fibreglass is non-conductive which would allow the build up of P-static.
This would in turn cause static interference on the antenna within so the radome is fitted with six conductive diverter strips on the outside to dissipate P-static into the airframe.
PURPOSE
1. The lightning diverters on a plane’s nose are metallic, highly conductive strips that are where lightning streamers originate, so that if a strike occurs, the lightning energy is directed down the strip to the metal frame of the aircraft rather than puncturing the composite and non-conductive radome.
2. Lightning diverter strips save the equipment inside a radome from lightning damage, and the segmented button structure causes the lightning to jump from segment to segment in the air, thus creating less heat onto the radome surface itself.
How Does a Lightning Diverter Strip Work?
A segmented lightning diverter is a thin strip of metal discs with gaps between them, that attracts lightning away from vital composite components – such as radomes – that contain sensitive radar and other equipment on aircraft.
Diverters work by directing the flow of lightning away from composite components, which cannot handle the high current and heat generated by lightning.
This allows it to pass harmlessly through the skin of the airplane and back into the air. These are mounted on composite radomes to protect the sensitive instrumentation and radar equipment inside.
How does an aircraft lightning protection system work?
Aircraft have a few lines of lightning protection, but segmented lightning diverters are typically the first defense and the place lightning will first strike.
1. Lightning is attracted to the segmented lightning diverter and strikes it, jumping from segment to segment through the air in an ionized channel.
2. The lightning then is directed to a screw or metal bar diverted that directs the lightning energy into the metal skin of the aircraft.
3. The lightning flows safely through the skin of the aircraft
4. Finally, the lightning leaves the aircraft skin and returns to the air, where it finishes its path to the earth to find ground.
