When buying a helmet you pay most attention to price, painting, accessories to improve comfort, and very rarely to the design and type of materials from which it was made. On the contrary, it should be quite the opposite because in the event of an accident this helmet is the most important protection of the pilot..
The material in which the helmet shell is made has a great impact on its durability, weight, and above all safety, so our airborne sports helmets are made exclusively of materials offering the highest levels of protection - fiber glass and carbon fiber. For the same reason we do not have ABS, resin, thermoplastic or polycarbonate shell in our offer.
Below we present the main differences between fiber glass and carbon fiber, which knowledge will help in selecting the optimum set.
Manufacturers make fiberglass and carbon fiber helmets in a fairly similar way. The only real differences are the chemical compositions of the solutions used to build the shell. Strands of fibers are gradually built up in layers inside a mold. The manufacturer seals each layer in place with a resin, which is allowed to dry before pasting the next layer over the top. The fibers in each layer run at different angles to each other, creating greater torsional strength between the layers.
Carbon fiber is significantly lighter than fiberglass. It's common in aircraft, sports cars and military equipment for this reason. A lightweight helmet improves pilot safety because it reduces fatigue. Helmet design is usually a trade-off between the different properties of a material. The lighter a helmet is, the easier it is for the rider to wear, but if it's too light, the strength will be compromised..
Fiberglass is a strong and tested material that can provide effective protection. However, compared to carbon fiber it is more brittle and tends to dissipate the impact energy through disintegration. In most cases this is not a problem; The helmet absorbs impact and the pilot is safe. However, when the accident is more complex (which often happens in air sports) and the helmet has to "absorb" several times the impact energy, the fiberglass crust may break prematurely, exposing the user to injury at subsequent stages of the accident. Carbon fiber, with much more flexibility, will better behave in such a situation, providing a higher level of protection.
As opposed to most other materials, carbon fiber has a negative coefficient of thermal expansion. This means that it expands when the temperature lowers. This is a desirable quality for applications that have to operate in a wide range of temperatures. For this reason, the helmet is made of carbon fiber much better suited for year-round use than its fiberglass counterpart.
Nothing is eternal. During operation, the shell of the helmet is affected by many external factors such as temperature, UV radiation, moisture. This makes the material from which the shell is made is subject to gradual degradation decreasing its original parameters. In this respect, carbon fiber is much more resistant to ?aging" than its glass counterpart. NAVCOMM recommends, depending on the intensity of use, to replace the fiberglass helmets every 3 to 5 years, and carbon fiber at the latest after 7 years.
Fiberglass has always been the cheaper option for airborne sports helmets. Carbon fiber is a "prestige" material and commands a high price tag due to its higher costs of production and manufacturing. In some ways, this reflects the appropriate market for each type. The high-priced carbon helmets are more likely to be purchased by people riding high-performance race-ready machines, that are more likely to be involved in high-speed crashes that would require the additional protection. Fiberglass helmets are more than adequate for those riders on slower machines, more likely to be involved in minor spills.
As the DEKRA experts has shown, the gluing or painting of the helmet, due to the fact that the solvents contained in the stickers and varnishes damage the surface of the helmet can be a reason of violates shell's stability. The same effect results in the execution of additional holes in the shell, for example under the brackets for cameras.