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The “Rigidization-on-Command”™ (ROC™) resin development has focused on the development of resin systems that use UV light cure for rigidization. Polymeric sensitizers have been incorporated into the resin formulations to promote cure using Pen-Ray lamps and UV light-emitting diodes (LED's). Formulations containing the polymeric sensitizers were examined by FTIR and DSC. Complete cure was observed after 15 min. exposure with the Pen-Ray lamps. Performance of the Pen-Ray lamps and UV LEDs was thoroughly characterized. Thermal models were developed to optimize the performance of the of the MLI insulation thermal oven used for orbital cure of the boom. Results show that -12°C is the lowest temperature required for cure of the ROC™ resin systems.

This paper describes the engine design details of the Pratt & Whitney JT15D-1 engine as related to noise generation. Design principles and factors contributing to the very low-noise levels on the Cessna Citation aircraft are illustrated. Noise testing experiences and data from static tests on the United Aircraft of Canada Ltd. (UACL) flight test aircraft and from both static and flight tests on the Citation aircraft are discussed. Lessons learned from these tests and some future probabilities are outlined.

THE FIRST YEAR of jet airline operation has brought many problems — and satisfactions — to the industry. Here the author discusses some of the more serious problems: 1. Scheduling. American Airlines used the “Monte Carlo” method to calculate payloads and flight times. 2. Baggage handling. Almost nothing annoys a passenger more than long waits for baggage at the end of a flight. One approach to the problem is the baggage expediter system. 3. Mechanical shutdowns. 4. Runway length. 5. Noise. Noise suppressors have not been effective enough, from the standpoint of communities surroundings airports. Development of the turbofan engine offers some hope in this area.*

THIS PAPER outlines progress to October, 1958, on the new Shock and Vibration Manual. At that point, the methods of solving vibration isolation problems had been established. After further refinements and expansion, the manual will be issued by SAE Committee S-12 on Shock and Vibration. The manual will set up procedures to be followed by engineers who don't have extensive experience in the field. It will give procedures for problems having up to six degrees of freedom. The procedure, as described in the paper, now consists of three steps: 1. Specification of the data required for the solution of a given problem. 2. Calculating whether vibration isolators are needed. 3. Determining the dynamic properties of the isolation system when the above step indicates isolation mounts are needed.

This specification covers a zinc alloy in the form of die castings.

(From Standards Proposal No. 2358, formulated under the cognizance of the EIA Quality and Reliability Engineering (QRE) Committee.)

Conventional attribute sampling plans based upon nonzero acceptance numbers are no longer desirable. In addition, emphasis is now placed on the quality level that is received by the customer. This relates directly to the Lot Tolerance Percent Defective (LTPD) value or the Limiting Quality Protection of MIL-STD-105. Measuring quality levels in percent nonconforming, although not incorrect, has been replaced with quality levels measured in parts per million (PPM). As a result, this standard addresses the need for sampling plans that can augment MIL-STD-105, are based upon a zero acceptance number, and address quality (nonconformance) levels in the parts per million range. This document does not address minor nonconformances, which are defined as nonconformances that are not likely to reduce materially the usability of the unit of product for its intended purpose.

This specification covers a zinc alloy in the form of die castings.

The X-38 vehicle will be used to demonstrate the future technology on durable TPS for the CRV. Astrium has produced two large CMC Nose Skirt side panels for the current X-38 configuration. The design of the 3 dimensional curved and large side panels comprises a light-weight, stringer stiffened concept which compensates the thermal expansion by a system of flexible metallic stand-offs. An optimum in flexibility and stiffness to fulfil all requirements had to be found: strong and stiff enough to carry the thermo-mechanical loads, but flexible enough to realise a fastening concept which does not fail due to thermal expansion. The fastening concept has been tested on development test level. Some thermal and mechanical tests on sub-structure level confirmed the design and analysis work of the complete TPS concept.

LiquidPiston Inc. has developed a new engine that can run on multiple fuels, including diesel, jet fuel, and gasoline. This platform uses an optimized thermodynamic cycle and a new rotary engine architecture and could increases flight endurance over conventional UAV engines by greater than 50%.

As part of its educational experience, the Noise & Vibration Conference begins with focused instructor-led workshops designed for those new to NVH or those looking for a refresher on a given topic.

Performance of Avionics systems is dictated by the timely availability and usage of critical health parameters. Various sensors are extensively used to acquire and communicate the desired parameters. In today's scenario, sensors are hardwired. The number of sensors is growing due to automation which increases the accuracy of intended Aircraft functions. Sensors are distributed all over the Aircraft and they are connected through wired network for signal processing and communication. LRUs (Line Replaceable Unit) which are integrating various sensors also use a wired approach for communication. The use of a wired network approach poses challenges in terms of cable routing, stray capacitances, noise, mechanical structure and added weight to the structure. The weight of cables contributes significantly to the overall weight of the aircraft. As the weight of Aircraft increases, the required fuel quantity also increases. The Key driver for Airline operational cost is fuel.

This specification covers one type of bronze in the form of round wire 0.500 inch (12.70 mm) and under in nominal diameter (see 8.5).

High-contrast IR wire grid polarizers from Edmund Optics are suited for broadband infrared applications that require high transmission and contrast, including spectroscopy and thermal imaging.

This paper discusses the importance of enroute wind conditions and the need for a wind measurement system which provides accurate and timely observations of wind and temperature conditions aloft. Recent advances in remote measurement of winds, temperature, and humidity such as the Stratospheric-Tropospheric radars and profilers developed at the National Oceanic and Atmospheric Administration’s Environmental Research Lab form the basis of such a system. A domestic system could and should be established using these devices together with a near real time winds aloft data dissemination network. Estimates of the saving in aircraft fuel consumption benefits range from 1 to 3 percent per year, or from $ 100 to $ 300 million for U.S. aviation system users at current prices and consumption.

This paper is concerned with the development of statistical models for the gust field in the lowest 300 ft of the atmosphere. It presents some of the highlights of the underlying physics principles, what is known about gusts, and how gusts affect aircraft. The difficulties of developing gust models are accounted for by the lack of data in particular areas and thus direct attention to the work required to provide the needed information.

THIS paper presents a brief historical review of the quest for information concerning the mechanism of aircraft noise generation. It is shown that, after a number of false hypotheses, the noise of propellers was finally traced to the principal aerodynamic loads of the blades. The intensity and characteristics of the noise can now be predicted theoretically from knowledge of the geometry and operating conditions of the propeller. With regard to jet noise, the picture is not so clear. The actual mechanism of noise generation is still somewhat obscure. Included here is a resume of United States and British work on determining the actual source of noise. Experiments on devices for reducing noise are also discussed.

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