What is EPO/EPS foam?
Eventually everyone comes across the term EPO foam, when it comes to RC Jets, and with this guide we are going to help everyone understand what EPO foam is. The first thing we are going to do is define EPO foam, EPO stands for Expanded PolyOlefin. The official name might not exactly help you understand what it does compared to other foams used in model aircraft. EPO foam is a tougher and more durable foam that will return to it original form with much more exaggerated stresses. Below is a image that was posted in an RCgroups forum showing the flexibility of EPO foam on a glider.
As you can see the nose of this glider is being forcefully manipulated, and it is able to resist cracking or snapping under higher stresses than standard foams.
So why is EPO foam used in RC EDF jets? What are the advantages over other foams? Well the reason EPO foams are a good fit is because of the speed of these jets and the violence of some of the crashes. EPO foam is heavier than more simple lightweight foams, like EPS or EPP foams, but it is much stronger and durable. In theory a lighter RC jet is a better RC jet for a number of reasons, but with the amount of thrust and power in a ducted fan jet, EPO is applicable.
The fact that your EDF RC jet might be made up of EPO foam in some sort of way, doesn't mean you can fly it with reckless abandon. Your jet with still break in a high speed or violent crash, but what it does do is reduce the chances of damages while handling, or at lower speed crashes, such as take -offs and landings. So next time you see EPO in a product description, you will know what its all about.