A compact radar for helicopters

The pilot of a Hiller UH12 helicopter engaged on crop-spraying in Lincoln- shire failed to see the spur of a power line to a farm. The helicopter hit the wires which damaged the con- trol rods and caused it to climb out of control until it crashed into a field. Over the last six years the number of United King- dom registered helicopters sustaining damage from hitting power cables has run into double figures. Helicopter accidents oc- cur during a diversity of tasks. Many happen while crop-spraying, but others happen on surveys, low- level photographic work, and military operations. Such examples of ac- cidents to helicopters are repeated in international air accident statistics. Wherever this type of air- craft operates at low altitude, it is vulnerable to the hazards of poor visi- bility and unseen ob- stacles, particularly power lines, or both. Even when power lines have been clearly visible to the pilot, accidents have happened because he has been unable to estimate ac- curatel...