Aircraft Foams
When you think of flying in comfort, your mind may not automatically go to foams. But, in reality, it is the materials you do not see that make the greatest impact on your flying comfort and experience. Below, OmnAvia Interiors’ CEO, Robin Butler, shares his specialized industry knowledge on aircraft foams, how they are designed, and the comfort options OmnAvia Interiors provides.
Q & A
Q: I know foam is a big deal in the aviation industry. Can you give me some background on foam and how it has developed?
A: Before the days of oil burner testing of seat cushion assemblies, seat cushions were made from high-resilience polyurethane (HRPU) foams. Regulations changed in the early 1980s. There was an on-board fire caused by a cigarette dropped into a lavatory trash can that fatally injured Curtis Mathes, the Canadian television manufacturing magnate. The Air Canada DC-9 made an emergency landing in Cincinnati, and moments after the plane rolled to a stop and the doors were opened for the passengers to escape, a flash-over occurred inside the cabin that took the lives of 23 passengers who had not yet escaped. The post-crash investigation resulted in significant changes in regulations designed to reduce the release of smoke and toxic gases of burning materials on board, which was determined to be the cause of most of the fatalities.
One of the new regulations requires all passenger seat cushions to withstand an 1,800-degree flame for 2 minutes. The solution was to wrap the foam cushions with a fire-retardant fabric that would protect the cushion from ignition. This construction added weight to the aircraft that increased fuel consumption and carbon emissions. A flammability testing company in Illinois named Skandia recognized that a flame retardant foam could eliminate fire block fabric layer. Skandia found a source for flame retardant foam and obtained an exclusive right to sell certain versions of that particular foam, known as DAX foam, to the private aircraft and business jet market. Many OEMs and seat manufacturers adopted this foam for installation on their seat assemblies. DAX became the leading foam in the industry among US aircraft producers.
When seat frame assemblies are certified to FAA standards today, they undergo dynamic testing, otherwise known as “sled testing” which involves crash test dummies, impact test measurements, weight and center of gravity measurements and so forth. There are a multitude of values that are electronically measured for each test and each seat assembly. Many of these values can change when foam is changed due to changes in foam density. If a seat is certified to 16G standards with a particular seat cushion foam assembly, the only way you can change the foam on that seat is to perform dynamic (sled) testing. This test can approach $100,000 for a single test, which makes it economically unfeasible to change the foam manufacturer once the seat is FAA certified.
If a seat assembly is certified to 16G standards using DAX foam sold by Skandia, that foam cannot be changed without recertification.
The board foot price for DAX foams has increased from about $7.00 to about $14.50 in just a few years due to a change in ownership of the company. Our OmnaFoam Platinum is made of Recticel foam. Our price for Recticel foam, depending on the firmness and depending on the volume, is anywhere from $8.50 to $9.25 a board foot.
Q: Let’s go more in-depth on the fire testing of foams. How is that test constructed?
A: For oil burner flammability testing, there are three parameters and pos that are measured – weight loss, burn-through length, and flaming drips of foam duration after the test is stopped. Three sets of vertical and horizontal specimens that replicate the complete seat cushion assembly, are all wrapped with the materials. Each set of specimens is weighed prior to testing. Those specimens sit in a steel frame. A “flame thrower” emits an 1,800 degree flame for two minutes. The flame is stopped and the specimens are observed for an additional five minutes.
The three parameters that they measure for pass/fail are:
- What is the length of burn across and burn through this specimen? That burn through can be no longer than 17 inches average.
- After the test is finished, you weigh each set of specimens again. You cannot exceed 10% weight loss average among the three sets of specimens. Two of the three sets must be less than 10% loss.
- The third parameter is after the flame has been taken away; how long do the specimens continue to drip flaming bits of foam and other materials? These flaming drips cannot continue past 5 minutes.
Q: Other than flame-resistance, what are the other important factors that are considered when specifying foams?
A: Comfort is the next most important consideration, and firmness differences are the factor that allow us to customize seating comfort. All seating foams will have different options for firmness to be utilized depending on their end-use. Most cushions are built up with different firmnesses of foam to maximize durability and comfort. You may have a base foam that is very firm, with a softer foam that’s glued to the top of the base for additional comfort. Additional foam is used for padding and shaping the final cushion design.
The firmness of all foams is rated by their ILD or IFD (Indentation Load or Force Deflection). How is this value determined? A four-inch cube of foam is placed in a testing apparatus and compressed to two inches. The amount of force in pounds required to compress that foam to a certain percentage of its original thickness determines the ILD/IFD value. A firmer foam requires more force, and thus receives a higher numerical value.
Q: I know OmnAvia offers a range of foam products. What are some of the foam products you offer and what sets OmnAvia apart as an alternative supplier of foam products?
A: From a seating standpoint, OmnaFoam Platinum is our graphite-impregnated foam. We also sell OmnaFoam Gold, which is a HRPU urethane foam that qualifies for Part 91 aircraft that are for personal/private use. Gold is not flame retardant like our Platinum foam, but you can make it flame retardant by wrapping it in a fire blocker material. We provide OmnaPad carpet padding. It’s made of foam and an FR fiber layer that provides thermal insulation and fire protection – the fiber is O-Pan and will not burn – ever. We also offer a variety of different panel foams in our collection. OmnAvia’s range of foams cover nearly every application in the aircraft from seat cushions to panel coverings foams that not only provide padding, but also thermal and acoustical insulation.
In those instances where users can select the foam of their choice, they often come to us. We don’t have a minimum order requirement, we offer a wide variety of foams, and our pricing is very competitive. Best of all, it’s much easier for them to place one purchase order and take care of all their requirements. And if somebody wants to buy one sheet, we’ll sell them one sheet. Whatever the customer needs from a foam perspective, OmnAvia has got them covered.
High Quality Comfortable, Insulating, & Fire Protecting Foams
OmnAvia specializes in providing a range of high quality comfortable, insulating, and fire protecting foams for aircraft interiors. The team at OmnAvia will work with you to understand your needs and applications to find the foam that is perfect for your aircraft.
Want more information on OmnAvia’s foam options? Contact Us today!