Abstract: A method of creating a water resistant, silicate-based ceramic composite article is disclosed. The method comprises depositing the silicate-based ceramic composite article in a container; immersing the silicate-based ceramic composite article in a solution comprising water and a soluble chemical that reacts with high alkali ions present in the silicate-based ceramic composite article and reduces the pH of the silicate-based ceramic composite article; soaking the silicate-based ceramic composite article in the solution for a period of time; removing the silicate-based ceramic composite article from the solution; and drying the silicate-based ceramic composite article.

Abstract: A collision alerting and avoidance system for use in an aerial vehicle is presented herein. The system comprises a one low profile antenna array disposed on the aerial vehicle. A transmitter/receiver probe is coupled to the antenna array. The transmitter/receiver probe is configured to transmit electromagnetic waves and to receive an echo signal reflected from a threat obstacle. At least one transmitter/receiver module is coupled to the transmitter/receiver probe. The transmitter/receiver module is configured to produce electromagnetic waves for transmission and to receive the echo signal. A processor coupled to the plurality of transmitter/receiver modules controls the transmission of electromagnetic waves from the antenna array and processes the echo signal to provide an output signal containing information regarding the obstacle.