Place the ice screw at 45 deg to the ice and then remove. The longer the
ice screw the stronger the thread will be.
a second hole again at 45 Deg less than the length of your screw away from the first
hole. The tricky bit is then to aim so that it reaches the end of the
a sling or piece of cord into one of the holes (thin spectra sling works
well). Then attempt to hook the end of it through the other hole and pull
it out. A drive in ice screw is suitable for this use and likely to be at
hand, or you could carry a piece of coat hanger wire specifically for this