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Technical Paper

11 Rules of Design for Manufacturing when Producing Pre-Impregnated Carbon Fiber-Reinforced Plastic Components - an Application at SAAB Aerostructures

2016-09-27
2016-01-2124
Carbon fiber-reinforced plastic (CFRP) is one of the most commonly used materials in the aerospace industry today. CFRP in pre-impregnated form is an anisotropic material whose properties can be controlled to a high level by the designer. Sometimes, these properties make the material hard to predict with regards to how the geometry affects manufacturing aspects. This paper describes eleven design rules originating from different guidelines that describe geometrical design choices and deals with manufacturability problems that are connected to them, why they are connected and how they can be minimized or avoided. Examples of design choices dealt with in the rules include double curvature shapes, assembly of uncured CFRP components and access for non-destructive testing (NDT). To verify the technical content and ensure practicability, the rules were developed by, inter alia, studying literature and performing case studies at SAAB Aerostructures.
Technical Paper

1953 Paper Jet Operations in Retrospect with Connotations for the Supersonic Transport

1965-02-01
650231
A first attempt to study civil aircraft operations comprehensively, prior to having the airplane, occurred before the initial operation of U.S. subsonic jets. One airline carried out a manual-simulated “paper jet” operation lasting fifteen months. Today, computerized simulation of machines, methods, and operations has become commonplace, and replaces the slide rule and tedious day-by-day inputs of aircraft operational criteria. Computerized simulations are also applied to every aspect of the SST design and operations. These are important, but the results being should be used with caution and judgement.
Technical Paper

1998/1999 AIAA Foundation Graduate Team Aircraft Design Competition: Super STOL Carrier On-board Delivery Aircraft

2000-10-10
2000-01-5535
The Cardinal is a Super Short Takeoff and Landing (SSTOL) aircraft, which is designed to fulfill the desire for center-city to center-city travel by utilizing river “barges” for short takeoffs and landings to avoid construction of new runways or heliports. In addition, the Cardinal will fulfill the needs of the U.S. Navy for a Carrier On-board Delivery (COD) aircraft to replace the C-2 Greyhound. Design requirements for the Cardinal included a takeoff ground roll of 300 ft, a landing ground roll of 400 ft, cruise at 350 knots with a range of up to 1500 nm with reserves, payload of 24 passengers and baggage for a commercial version or a military version with a 10,000 lb payload, capable of carrying two GE F110 engines for the F-14D, and a spot factor requirement of 60 feet by 29 feet.
Technical Paper

1D Modelling of Thermal Management of a Jet Trainer Aircraft

2023-03-07
2023-01-1005
Most of current jet aircraft circulate fuel on the airframe to match heat loads with available heat sink. The demands for thermal management in wide range of air vehicle systems are growing rapidly along with the increased mission power, vehicle survivability, flight speeds, and so on. With improved aircraft performance and growth of heat load created by Aircraft Mounted Accessory Drive (AMAD) system and hydraulic system, effectively removing the large amount of heat load on the aircraft is gaining crucial importance. Fuel is becoming heat transfer fluid of choice for aircraft thermal management since it offers improved heat transfer characteristics and offers fewer system penalties than air. In the scope of this paper, an AMESim model is built which includes airframe fuel and hydraulic systems with AMAD gearbox of a jet trainer aircraft. The integrated model will be evaluated for thermal performance.
Journal Article

2-Stroke High Speed Diesel Engines for Light Aircraft

2011-09-11
2011-24-0089
The paper describes a numerical study, supported by experiments, on light aircraft 2-Stroke Direct Injected Diesel engines, typically rated up to 110 kW (corresponding to about 150 imperial HP). The engines must be as light as possible and they are to be directly coupled to the propeller, without reduction drive. The ensuing main design constraints are: i) in-cylinder peak pressure as low as possible (typically, no more than 120 bar); ii) maximum rotational speed limited to 2600 rpm. As far as exhaust emissions are concerned, piston aircraft engines remain unregulated but lack of visible smoke is a customer requirement, so that a value of 1 is assumed as maximum Smoke number. For the reasons clarified in the paper, only three cylinder in line engines are investigated. Reference is made to two types of scavenging and combustion systems, designed by the authors with the assistance of state-of-the-art CFD tools and described in detail in a parallel paper.
Book

2009 Ultimate GD&T Pocket Guide 2nd Ed

2017-03-27
The Ultimate GD&T Pocket Guide explains the most common rules, symbols, and concepts used in geometric dimensioning and tolerancing. ...This one-of-a-kind reference guide includes over 100 detailed drawings to illustrate concepts, more than 40 charts for quick reference, explanations of each GD&T symbol and modifier and much more...Written by standards expert Alex Krulikowski, this valuable on-the-job reference clarifies how to interpret standard-compliant technical drawings that use ASME Y14.5-2009.
Article

2050 aircraft engine designs go radical, part 1

2018-10-23
The search for ever-lower emission technology for future generations of aircraft engines is actively progressing on both sides of the Atlantic. Tucked away on a modest-size stand at this year’s Farnborough International Airshow was a highly varied collection of unconventional engine technology displays – a clear indication of radical innovation already being investigated as a part of Ultimate, the European Horizon 2020 research and innovation project.
Article

2050 aircraft engine designs go radical, part 2

2018-10-24
In part two of a two-part series, Richard Gardner discusses various aerospace propulsion innovations and continued work by aerospace engineers and scientists to advance aircraft engine technologies to increase efficiency and lower emissions.
Technical Paper

21st Century Aircraft Potable Water Systems

1999-10-19
1999-01-5556
Aircraft potable (drinking) water systems haven’t changed significantly in the last half-century. These systems consist of cylindrical water tanks pressurized by bleed air from the jet engines, with insulated stainless steel distribution lines. What has changed recently is the increase in the possibility of aircraft picking up contaminated drinking water at foreign and domestic stops. Customer awareness of these problems has also changed - to the point where having reliable drinking water is now a competitive issue among airlines. Old style potable water systems that are used on modern aircraft are high maintenance and exacerbate the growth of microbes because the water is static much of the time. The integrity of some pressurized water tanks are also a concern after years of use. Cost-effective mechanical and biological solutions exist that can significantly reduce the amount of chemicals added and provide good potable water.
Technical Paper

21st Century Lunar Exploration: Advanced Radiation Exposure Assessment

2006-07-17
2006-01-2106
On January 14, 2004 President George W Bush outlined a new vision for NASA that has humans venturing back to the moon by 2020. With this ambitious goal, new tools and models have been developed to help define and predict the amount of space radiation astronauts will be exposed to during transit and habitation on the moon. A representative scenario is used that includes a trajectory from LEO to a Lunar Base, and simplified CAD models for the transit and habitat structures. For this study galactic cosmic rays, solar proton events, and trapped electron and proton environments are simulated using new dynamic environment models to generate energetic electron, and light and heavy ion fluences. Detailed calculations are presented to assess the human exposure for transit segments and surface stays.
Technical Paper

26 X 6.6 Radial-Belted Aircraft Tire Performance

1991-09-01
912157
Preliminary results from testing of 26 X 6.6 radial-belted and bias-ply aircraft tires at NASA Langley's Aircraft Landing Dynamics Facility (ALDF) are reviewed. These tire tests are part of a larger, on going joint NASA/FAA/Industry Surface Traction and Radial Tire (START) Program involving three different tire sizes. The 26 X 6.6 tire size evaluation includes cornering performance tests throughout the aircraft ground operational speed range for both dry and wet runway surfaces. Static test results to define 26 X 6.6 tire vertical stiffness properties are also presented and discussed.
Standard

265°F Vacuum Cure, Epoxy Prepregs

2017-11-08
WIP
AMS6566
The purpose of this specification is to allow procurement of a defined material corresponding to statistically derived material properties published in CMH-17. This material is intended for use in laminate applications with a service temperature up to 180 °F. They are typically used in structural applications requiring high strength and stiffness. This is the base specification and it will have one slash/detail specs.
Standard

265°F Vacuum Cure, Epoxy Prepregs Type 42, Class 2, Grade 193, Style 12K-193-SFP-OSI

2017-11-10
WIP
AMS6566/1
The purpose of this specification is to allow procurement of a defined material corresponding to statistically derived material properties published in CMH-17. This material is intended for use in laminate applications with a service temperature up to 180 °F. They are typically used in structural applications requiring high strength and stiffness. This is the base specification and it will have one slash/detail specs.
Standard

265°F, Autoclave Vacuum Bag Cure, Epoxy Prepreg, Type 33, Class 1, Grade 148, Intermediate Modulus Carbon Fiber

2017-11-10
WIP
AMS6568/1
The purpose of this specification is to allow procurement of a defined material corresponding to statistically derived material properties published in CMH-17. This material is intended for use in laminate applications with a service temperature up to 180 °F. They are typically used in structural applications requiring high strength and stiffness. This is the base specification and it will have three slash/detail specs.
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