When your airplane’s in annual, you probably monitor the caller ID with dread, living in fear of a call from your A&P that portends something expensive. If your airplane has de-ice boots—approved for known icing or not—they could easily be this year’s money hole. A full-up replacement set can cost, installed, anywhere from $11,000 for a single to $20,000 for twins.
We’ll talk about expected boot life in just a moment, and there are ways to extend it. However, what we did learn from our investigation was that when it’s time to replace one or all of the boots on your airplane, procrastinating is likely to increase the cost. When boots have significant air leaks, it not only means the vacuum pump works harder to inflate them, but the entire system is working constantly to keep them sucked flat against the airframe. That means that moisture is getting sucked into the system.The result is that the valves, hoses, relays and other components, which ordinarily last longer than the boots themselves, are more likely to suffer from early retirement.