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Significant environmental and economic benefit could be obtained if spark ignited (SI) engines could be made more efficient. Engine operation using leaner fuel air mixtures at higher power densities and pressures promise higher thermal efficiencies. Mixtures required for such operation are often difficult to ignite with traditional spark plugs. In pursuit of better ignition sources, this paper presents a high-level model of an alternative microwave plasma ignition source under development. In this publication, atmospheric measurements of a pulsed microwave ignitor are used to derive an empirical model that will allow for control and increased energy delivery to the device. The model accounts for a simplistic plasma formation delay, a drop in resonance frequency as a result of plasma formation, and a subsequent change in associated microwave reflection coefficient.

At flight levels above the ceiling of 10,000 feet, during the operational phase of a sensor deployment system for a C-130 aircraft, it becomes necessary to seal the cargo hold to maintain pressure for the safety and comfort of the crew and operators. In order for the sensor deployment System to have full mission support capabilities for DoD reconnaissance needs, a system must be designed where-by the cargo area may be sealed once the system has been deployed. Currently, with the sensor pod in position, the ramp can be closed to within a few inches of the locked position. The door in this position, for stability during flight, must be locked and structurally supported to maintain the aircrafts design requirements. This presents the first of a series of issues that must be examined for the success of the final design. To seal the remaining area, an expanding “bladder-seal” has been developed.

Previous studies have shown that using blowing slots can reduce the effects of the rotor downwash on the main wing of a tilt-rotor aircraft, particularly the V-22 Osprey. The current study investigates the placement and air velocity of the leading edge blowing slot for optimization of the download reduction. The realizable turbulent kinetic energy - rate of dissipation (rke) numerical model available in Fluent 6.2.12 was used to model the flow involved under the rotors and the subsequent downwash around the main wing. It was found that the leading edge blowing slot is most beneficial when it is placed just upwind of the separation point without blowing slots. In the current investigation the optimal configuration is found between 0 percent and 1 percent of the chord length.

When designing the Oculus sensor platform, many safety issues such as designing fail safes, adapting to flying situations, and examining situations produced by exposure to real-world conditions were taken into consideration. When predicting maintenance issues, environmental conditions that the platform will have to encounter were assessed. A material that was lightweight and strong enough to withstand the harsh environmental conditions experienced outside the C-130 aircraft was needed. In addition to the material used, another issue addressed was the ability to repair the platform easily and efficiently. Normal operations expose the components to significant wear and tear, which requires the replacement of parts to maintain safe operations. Oculus was constructed to allow for component replacement without deconstruction of the entire platform. While environmental factors were a concern, mechanical design and functionality, along with safety, was vital to the project.

Enhancing the capabilities of established airframes to meet expanded mission requirements is preferential to the design of specialized aircraft. The high cost associated with the research and development of a specialized aircraft platform has shifted the concentration towards the modification of existing aircraft to support multiple C4ISR missions. The recently developed Oculus sensor deployment system is one such example of this trend, providing a fully integrated aerial visual enhancement platform with multi-mission capabilities. This paper provides a short survey of the Oculus sensor pallet system and overviews some of the multiple guidelines used which ensure that various remote sensing technologies may be securely and simultaneously deployed.