On the other hand....

We were helivacing an injured hiker from the Santa Catalina Mts., just north of Tucson, employing a Air Force bird from Davis-Monathan AFB (which lies within Tucson). As the sun rose, they asked for a mirror flash. I obliged, "painting" Tucson in the general area of D-M AFB, because I had no knowledge of their precise location. Sky conditions were moderately hazy, and they were at least ten miles distant.

They received flashes and had a fix on their objective before liftoff. It is always a good idea to make it as easy as possible for the helicopter pilot.

In most of our usage of signal mirrors, we did not know the specific location of our target. Painting was SOP....