Lasers Produce Shark Skins on Aircraft

Alsdorf, Germany-based laser specialist, 4JET, and aircraft paint supplier Mankiewicz are introducing a new laser process for the creation of fuel saving riblets automatically lasered onto painted aircraft surfaces.

The technology – dubbed LEAF for Laser Enhanced Air Flow – uses the principle of laser interference patterning to quickly create fine lateral grooves in the uppermost layer of aircraft paint.

Such riblets have been proven to reduce drag by up to 10 percent which results in fuel savings for commercial long-haul airlines by more than 1 percent – equaling large potential savings on total global kerosene spending of $150 billion annually.

The process – while still in the development stage – already yields industrial throughput levels and has passed initial qualifications for durability.

Working Principle

Removing paint by lasers is a well-known technology but so far proved to be too slow to create the high density of riblets required to achieve “shark skin” effects. Instead of creating the riblet grooves with one focused laser spot line by line, 4JET has now found a way to speed up the process by a factor of about 500 using the principle of laser interference patterning:

The laser beam is split up and recombined on the surface in such a way that the electric field oscillations of the light waves superpose in a controlled manner. This superposition creates a distinct pattern of dozens of alternating equidistant lines of high and almost no intensity within one single laser spot. This enables to create 15 kilometers of riblets – equal to about 1 m2 of riblet surface – within less than one minute.

LEAF is working dry without any consumables. It allows to adjust riblet geometries depending on their location on the aircraft. The paint dust and vapor created during the process is evacuated and the process does not require post processing. The technology enables to process curved or riveted surfaces and, thanks to its long focal distance, can be integrated with existing robotics used for paint removal or printing operations in aircraft maintenance.

“We are looking forward to actively writing another chapter in the history of aviation coatings and shaping the future of sustainable aircraft. With 4JET we are glad to have such a competent partner of the laser industry at our side and look forward to the future cooperation and commercialization of this ground breaking new method to save fuel and thus contribute to a greener future,” says Andreas Ossenkopf, director – head of Aviation.

4JET CEO Jorg Jetter points out: “We are excited about the progress so far and the tremendous opportunities of our new partnership with Mankiewicz. LEAF could not only be opening up an entirely new market for our company, but deliver a significant contribution to cut down CO2 emissions in the aviation sector.”