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This document establishes the minimum criteria for effective training of air carrier and contractor personnel to deice/anti-ice aircraft to ensure the safe operation of aircraft during ground icing conditions. Appendix D specifies guidelines for particular airplane models.

Abstract More than a decade ago, we proposed combined use of direct injection (DI) and jet ignition (JI) to produce high efficiency, high power-density, positive-ignition (PI), lean burn stratified, internal combustion engines (ICEs). Adopting this concept, the latest FIA F1 engines, which are electrically assisted, turbocharged, directly injected, jet ignited, gasoline engines and work lean stratified in a highly boosted environment, have delivered peak power fuel conversion efficiencies well above 46%, with specific power densities more than 340 kW/liter. The concept, further evolved, is here presented for unmanned aerial vehicle (UAV) applications. Results of simulations for a new DI JI ICE with rotary valve, being super-turbocharged and having gasoline or methanol as working fuel, show the opportunity to achieve even larger power densities, up to 430 kW/liter, while delivering a near-constant torque and, consequently, a nearly linear power curve over a wide range of speeds.

Abstract Constant area section length downstream to the fuel injection point is a crucial dimension of scramjet duct geometry. It has a major contribution in creating the maximum effective pressure inside the combustor that is required for propulsion. The length is limited by the thermal choking phenomenon, which occurs when heat is added in a flow through constant area duct. As per theory, to avoid thermal choking the constant area section length depends upon the inlet conditions and the rate of heat addition. The complexity related to mixing and combustion process inside the supersonic stream makes it difficult to predict the rate of heat addition and in turn the length. Recent efforts of simulating the reacting flow inside scramjet combustors are encouraging and can be useful in this regard. The presented work attempts to use simulation results of scramjet combustion for predicting the constant area section length for a typical scramjet combustor.

Abstract Jet engine hot parts (e.g., jet nozzle) are a crucial source of aircraft’s infrared (IR) signature from the rearview, in 1.9-2.9 μm and 3-5 μm bands. The exhaust nozzle design used in a jet aircraft affects its performance and IR signature (which is also affected just by performance) from the engine layout. For supersonic aircraft (typically for M ∞ > 1.5), a converging-diverging (C-D) nozzle is preferred over a convergent nozzle for optimum performance. The diverging section of the C-D nozzle has a full range of visibility from the rearview; hence, it was not considered a prudent choice for low IR observability. This theoretical study compares the IR signature of the C-D nozzle with that of the convergent nozzle from the rearview in 1.9-2.9 μm and 3-5 μm bands for the same thrust.

Abstract The preliminary gas turbine combustor design process uses a huge amount of empirical correlations to achieve more optimized designs. Combustion efficiency, in relation to the basic dimensions of the combustor, is one of the most critical performance parameters. In this study, semi-empirical correlations for combustion efficiencies are examined and correlation coefficients have been revised using an experimental air-blasted tubular combustor that uses JP8 kerosene aviation fuel. Besides, droplet diameter and effective evaporation constant parameters have been investigated for different operating conditions. In the study, it is observed that increased air velocity significantly improves the atomization process and decreases droplet diameters, while increasing the mass flow rate has a positive effect on the atomization—the relative air velocity in the air-blast atomizer increases and the fuel droplets become finer.

To inform users on proper use, procedures and common errors when using electronic compensation for tooling on horizontal and vertical balancing machines

Provide guidance on how balance machine vector data is captured and reported. Provide an understanding of how to transform balance machine vector data to alternate locations. Provide guidance on how vector imbalances may be used to evaluate and diagnose balance process performance.

Set forth dimensions and specifications for Nickel Alloy N07718 100 deg csk 0.114” to 0.3750” diameter screws with AS6305 recess.

This document establishes process parameters for gas turbine rotor balancing. Adherence to the recommendations made herein will facilitate attainment of the usually high degree of accuracy and precision required for jet engine rotor balance.

The scope of these standards will relate to single-axis moment scales only. Topics covered include dimensional characteristics of single-axis moment scale interfaces, general tooling requirements, scale and tooling accuracy, and display instrument accuracy requirements. Additionally, general guidelines for qualification of equipment and tooling are included, as are general requirements for single-axis blade distribution software.

A guide to maintenance procedures in test cells. A suggested equipment monitoring and/or inspections to reduce the probability of unanticipated failures and associated test cell down time. Guidelines for using typically available data acquisition capabilities in a test cell are provided to utilize normally available trending capability to monitor the testing equipment in addition to using these tools for the usual monitoring of the test article. For the common types of test cells (turboshaft, turboprop, turbojet, and turbofan) test facilities, lists of typical systems with their associated components are provided with suggested inspection intervals and key items to look for in the inspection. A template risk assessment form is provided to facilitate the customization of the assessment of the test cell components to help predict recommended spares.

This new Aerospace Recommended Practice will serve as a practical resource that offers guidance to both the machine operator and Process Engineer for isolating the source(s) of non-repeatability in measured unbalance data. The content of this standard addresses: • Vertical Dynamic Machine Capability to achieve the specified unbalance tolerances and repeat within those tolerances • Tooling Capability to repeat within the specified unbalance tolerances • Rotor characteristics that may preclude repeating within the required unbalance tolerances.

This specification and its supplementary detail specifications cover para-aramid materials in the form of thread.

The report shows how the methodology of measurement uncertainty can usefully be applied to test programs in order to optimize resources and save money. In doing so, it stresses the importance of integrating the generation of the Defined Measurement Process into more conventional project management techniques to create a Test Plan that allows accurate estimation of resources and trouble-free execution of the actual test. Finally, the report describes the need for post-test review and the importance of recycling lessons learned for the next project.

An infrared laser absorption technique has been developed to measure in-cylinder concentrations of CO in an optical, automotive HCCI engine. The diagnostic employs a distributed-feedback, tunable diode laser selected to emit light at the R15 line of the first overtone of CO near 2.3 μm. The collimated laser beam makes multiple passes through the cylinder to increase its path length and its sampling volume. High-frequency modulation of the laser output (wavelength modulation spectroscopy) further enhances the signal-to-noise ratio and detection limits of CO. The diagnostic has been tested in the motored and fired engine, exhibiting better than 200-ppm sensitivity for 50-cycle ensemble-average values of CO concentration with 1-ms time resolution. Fired results demonstrate the ability of the diagnostic to quantify CO production during negative valve overlap (NVO) for a range of fueling conditions.