In the last five years, advances in materials, electronics, sensors, and batteries have fueled a growth in the development of microunmanned aerial vehicles (MAVs) that are between 0.1 and 0.5 m in length and 0.1-0.5 kg in mass . A few groups have built and analyzed MAVs in the 10-cm range , . One of the smallest MAV is the Picoftyer with a 60-mmpropellor diameter and a mass of 3.3 g . Platforms in the 50-cm range are more prevalent with several groups having built and flown systems of this size -. In fact, there are severalcommercially available radiocontrolled (PvC) helicopters and research-grade helicopters in this size range .