I have placed antenna inside models for years. But one day I was testing a larger model for a friend. Each time I tried to land the mdoel would go out of control for a moment. At first, I thought I had stalled it. But it happend again on subsequent attempts. Sometimes magnetic anomolies radiate upward from mineral deposites and interfere with radios near the ground. So Ialtered my aproach to avoid the area where "hits" had occured. The plane landed fine. But we discovered that the atenna , inside a tube and straight as a string was being blanked out by the larger engine whenever I flew directly at myself, (such as on approach). Its rare, Its a fluke. But it can happen.