Download or read book Advanced Subsonic Transport Approach Noise written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-30 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: With current engine technology, airframe noise is a contributing source for large commercial aircraft on approach, but not the major contributor. With the promise of much quieter jet engines with the planned new generation of high-by-pass turbofan engines, airframe noise has become a topic of interest in the advanced subsonic transport research program. The objective of this paper is to assess the contribution of airframe noise relative to the other aircraft noise sources on approach. The assessment will be made for a current technology large commercial transport aircraft and for an envisioned advanced technology aircraft. NASA's Aircraft Noise Prediction Program (ANOPP) will be used to make total aircraft noise predictions for these two aircraft types. Predicted noise levels and areas of noise contours will be used to determine the relative importance of the contributing approach noise sources. The actual set-up decks used to make the ANOPP runs for the two aircraft types are included in appendixes. Willshire, William L., Jr. and Garber, Donald P. Langley Research Center RTOP 537-03-21-04...

Download or read book Advanced Subsonic Transport Approach Noise The Relative Contribution of Airframe Noise written by and published by . This book was released on 1992 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nasa s Subsonic Jet Transport Noise Reduction Research written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-21 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although new jet transport airplanes in today s fleet are considerably quieter than the first jet transports introduced about 40 years ago, airport community noise continues to be an important environmental issue. NASA s Advanced Subsonic Transport (AST) Noise Reduction program was begun in 1994 as a seven-year effort to develop technology to reduce jet transport noise 10 dB relative to 1992 technology. This program provides for reductions in engine source noise, improvements in nacelle acoustic treatments, reductions in the noise generated by the airframe, and improvements in the way airplanes are operated in the airport environs. These noise reduction efforts will terminate at the end of 2001 and it appears that the objective will be met. However, because of an anticipated 3-8% growth in passenger and cargo operations well into the 21st Century and the slow introduction of new the noise reduction technology into the fleet, world aircraft noise impact will remain essentially constant until about 2020 to 2030 and thereafter begin to rise. Therefore NASA has begun planning with the Federal Aviation Administration, industry, universities and environmental interest groups in the USA for a new noise reduction initiative to provide technology for significant further reductions. Powell, Clemans A. and Preisser, John S. Langley Research Center

Download or read book Noise and Economic Characteristics of an Advanced Blended Supersonic Transport Concept written by John K. Molloy and published by . This book was released on 1982 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Subsonic Long haul Transport Terminal Area Compatibility Study Volume 1 Compatibility Assessment written by and published by . This book was released on 1974 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Quantitative Assessment of Advanced Take off Trajectories for Supersonic Transport Noise Reduction written by Laurens Jozef Amandine Voet and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis (a) establishes the design trades and limitations of supersonic transport propulsion systems in terms of take-off noise reduction, (b) identifies the attributes, quantifies the potential, and assesses the impact of advanced take-off trajectories designed for noise reduction, and (c) formulates a reduced-order model to scale these results for supersonic transport of different size classes and cruise Mach numbers. The propulsion system design trades established in this thesis show that clean- sheet engines do not enable supersonic transport to meet current subsonic transport noise limits when using conventional take-off trajectories. The impact of derivative engines on the cumulative noise levels is found to be small (1.4 EPNdB). In fact, regardless of whether a clean-sheet or derivative engine is selected, a Mach 1.4 business jet is shown to exceed the current cumulative noise limit by at least 15.5 EPNdB. Further noise reduction of the jet noise dominant engines is prevented by the fan size constraint imposed to limit wave drag during supersonic cruise. Advanced trajectories are proposed to reduce take-off noise by capitalizing on excess engine thrust and improved aerodynamic efficiency at higher take-off speeds. These novel trajectories use (i) automatic continuous control of thrust and high-lift devices, (ii) increased take-off speed, and (iii) reduced cut-back altitude, compared to conventional trajectories currently used for subsonic transport. For the aircraft examined, although these trajectories reduce the 65 dB-A community noise contour area by 63.8%, they only reduce cumulative certification noise by 10.6 EPNdB, which is insufficient to meet current subsonic transport noise limits. Additionally, advanced trajectories with the lowest community noise do not yield the lowest certification noise, which warrants re-examination of supersonic transport noise standards. On the contrary, engine NO[subscript x] standards are representative for supersonic transport using advanced take-off trajectories and thus do not need to be modified, as the impact of these trajectories on the mass of NO[subscript x] emissions during climb-out is small (16.1%). Last, a first-of-its-kind reduced-order model for supersonic transport take-off noise scaling shows that, as cruise Mach number increases, supersonic transport take-off noise levels increase while the thrust cut-back noise reduction potential decreases. This scaling rule enables equally stringent standard setting for noise certification of supersonic transport across a broad range of size classes and cruise Mach numbers.

Download or read book Airframe Noise Studies written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-15 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report contains the following information: 1) a review of airframe noise research performed under NASA's Advanced Subsonic Transport (AST) program up to the year 2000, 2) a comparison of the year 1992 airframe noise predictions with those using a year 2000 baseline, 3) an assessment of various airframe noise reduction concepts as applied to the year 2000 baseline predictions, and 4) prioritized recommendations for future airframe noise reduction work. NASA's Aircraft Noise Prediction Program was the software used for all noise predictions and assessments. For future work, the recommendations for the immediate future focus on the development of design tools sensitive to airframe noise treatment effects and on improving the basic understanding of noise generation by the landing gear as well as on its reduction. Rackl, Robert G. and Miller, Gregory and Guo, Yueping and Yamamoto, Kingo Langley Research Center NAS1-97040; 23-781-20-12

Download or read book Evaluation of the Advanced Subsonic Technology Program Noise Reduction Benefits written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-15 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents a detailed evaluation of the aircraft noise reduction technology concepts developed during the course of the NASA/FAA Advanced Subsonic Technology (AST) Noise Reduction Program. In 1992, NASA and the FAA initiated a cosponsored, multi-year program with the U.S. aircraft industry focused on achieving significant advances in aircraft noise reduction. The program achieved success through a systematic development and validation of noise reduction technology. Using the NASA Aircraft Noise Prediction Program, the noise reduction benefit of the technologies that reached a NASA technology readiness level of 5 or 6 were applied to each of four classes of aircraft which included a large four engine aircraft, a large twin engine aircraft, a small twin engine aircraft and a business jet. Total aircraft noise reductions resulting from the implementation of the appropriate technologies for each class of aircraft are presented and compared to the AST program goals. Golub, Robert A. and Rawls, John W., Jr. and Russell, James W. Langley Research Center 23-781-20-12

Download or read book Advanced Subsonic Long haul Transport Terminal Area Compatibility Study Volume 2 Research and Technology Recommendations written by and published by . This book was released on 1974 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Airframe Noise Studies written by Robert G. Rackl and published by BiblioGov. This book was released on 2013-07 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report contains the following information: 1) a review of airframe noise research performed under NASA's Advanced Subsonic Transport (AST) program up to the year 2000, 2) a comparison of the year 1992 airframe noise predictions with those using a year 2000 baseline, 3) an assessment of various airframe noise reduction concepts as applied to the year 2000 baseline predictions, and 4) prioritized recommendations for future airframe noise reduction work. NASA's Aircraft Noise Prediction Program was the software used for all noise predictions and assessments. For future work, the recommendations for the immediate future focus on the development of design tools sensitive to airframe noise treatment effects and on improving the basic understanding of noise generation by the landing gear as well as on its reduction.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1993 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recent Developments in U S Engine Noise Reduction Research written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-19 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aircraft engine noise research in the United States has made considerable progress over the past 10 years for both subsonic and supersonic flight applications. The Advanced Subsonic Technology (AST) Noise Reduction Program started in 1994 and will be completed in 2001 without major changes to program plans and funding levels. As a result, significant progress has been made toward the goal of reducing engine source noise by 6 EPNdB (Effective Perceived Noise level in decibels). This paper will summarize some of the significant accomplishments from the subsonic engine noise research performed over the past 10 years. The review is by no means comprehensive and only represents a sample of major accomplishments. Bridges, James and Envia, Edmane and Huff, Dennis Glenn Research Center NASA/TM-2001-211083, NAS 1.15:211083, ISABE-2001-1017, E-12927

Download or read book Some Technical Aspects of Advanced Subsonic Transport Aircraft written by Albert J. Evans and published by . This book was released on 1965 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Improved NASA ANOPP Noise Prediction Computer Code for Advanced Subsonic Propulsion Systems written by and published by . This book was released on 1996 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Analytical Assessment of Nasa s N 1 Subsonic Fixed Wing Project Noise Goal written by Nasa Technical Reports Server (Ntrs) and published by BiblioGov. This book was released on 2013-07 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Subsonic Fixed Wing Project of NASA s Fundamental Aeronautics Program has adopted a noise reduction goal for new, subsonic, single-aisle, civil aircraft expected to replace current 737 and A320 airplanes. These so-called "N+1" aircraft--designated in NASA vernacular as such since they will follow the current, in-service, "N" airplanes--are hoped to achieve certification noise goal levels of 32 cumulative EPNdB under current Stage 4 noise regulations. A notional, N+1, single-aisle, twinjet transport with ultrahigh bypass ratio turbofan engines is analyzed in this study using NASA software and methods. Several advanced noise-reduction technologies are empirically applied to the propulsion system and airframe. Certification noise levels are predicted and compared with the NASA goal.

Download or read book ASME 68 GT 61 written by J. J. Kramer and published by . This book was released on 1968 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technologies for Aircraft Noise Reduction written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-24 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Technologies for aircraft noise reduction have been developed by NASA over the past 15 years through the Advanced Subsonic Technology (AST) Noise Reduction Program and the Quiet Aircraft Technology (QAT) project. This presentation summarizes highlights from these programs and anticipated noise reduction benefits for communities surrounding airports. Historical progress in noise reduction and technologies available for future aircraft/engine development are identified. Technologies address aircraft/engine components including fans, exhaust nozzles, landing gear, and flap systems. New "chevron" nozzles have been developed and implemented on several aircraft in production today that provide significant jet noise reduction. New engines using Ultra-High Bypass (UHB) ratios are projected to provide about 10 EPNdB (Effective Perceived Noise Level in decibels) engine noise reduction relative to the average fleet that was flying in 1997. Audio files are embedded in the presentation that estimate the sound levels for a 35,000 pound thrust engine for takeoff and approach power conditions. The predictions are based on actual model scale data that was obtained by NASA. Finally, conceptual pictures are shown that look toward future aircraft/propulsion systems that might be used to obtain further noise reduction. Huff, Dennis L. Glenn Research Center