Here are some things for the Air Hogs Reflex helicopter that have worked for me to kill the death spiral:
Background: Bought Blue Reflex online 19 Feb 07 from Toys R US for $44.99 with $10 Google pay discount. It flew too fast forward out of the box, so I wrapped a 2.5 inch wire tie from the container it came in to the end of the tail. I had good hover and control after that. I flew it daily. Mainly inside, some outside when there was no wind or just a slight breeze. My Reflex heli, or my current skills, don't do well in any kind of even gentle breeze...The usual occasional crashes ensued over the days. They were all fairly minor and I was able to chop power to minimize gear damage. One of the things you might want to check is for stripped gears. This would not be easily, if at all fixable, so do chop power immediately when you see a potential crash about to happen. OK, lets do a little inspection. Line up the bottom blades with the body. When you do this, the top blades should be perpendicular. If they are not, that would indicate a possible stripped gear, probably accompanied by a rough grinding-like noise in the worst cases. If that is your problem, then you will likely have to do major surgery to fix this...or see if it can be returned...good luck with that. To further minimize damage to delicate and hard to find blades, I applied 2 inches of clear packing tape over the leading edges of all four blades. It still flew just fine. Then, after one minor crash a few days ago, the spiral of death, as described here and other r/c forums, reared its ugly head. These were ever increasing widening circles and speed that if left to continue would smash the little heli into anything in its wild path with possible further damage. I applied several "fixes" that worked for some others: First, I oiled the shafts at the bearings. I used 3-in-1 oil applied with a toothpick. Others have used WD-40. This is probably good maintenance, but it did not seem to correct the spiral for me. Second, I noticed the tail was very slightly twisted, so I straightened it. There still was no noticeable fix on the spiral. Third, I tightened the hub snugly all the way to the right and flew with the body spinning. I noticed it would stay in a hover this way...hey, some progress! Then I started turning the hub to the left one or two notices at a time and hovering it with the spinning body. I did this gradually until it stopped spinning. At this point, the spiral of death seemed to be reduced, but not eliminated. Then, upon close inspection, I noticed that the top of the bearing that the outer blade shaft goes into at the body of the heli, was sticking out of its hub, ever so slightly. I put the heli in my left hand and pushed down on the bottom blades hub with my right hand's fingers, forcing it back into the bottom of its seat. It really didn't take much pressure, so if you hit the gym everyday and lift the 60lb dumbbells’ in order to grow massive biceps to wow your girlfriends as you fly this little heli with its tiny controller, well then be gentle Reseating the bearing seemed to do the trick for me so far. It flies as stable as it did when new and has for the last few days now. I do not see any cracking in the plastic around this hub, but I might try a very carefully placed small amount of superglue to keep it in place. I have had to push it in a couple of more times after some crashes when the spiral returned. The good news is that reseating it did stop the spiral every time! Now, all of this said, any one of the above might work for you. I may have just hit on a lucky combination, but give'em all a try. Please add more fixes to this forum string if you come across or find any that work for you.
Good luck and happy hovering!
Jim