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Concluding remarks
Published in Doramas Jorge-Calderón, Aviation Investment, 2020
Reliable estimates of user willingness to pay to reduce trip duration are important for aircraft manufacturers in estimating the underlying demand potential for new products, particularly when they are innovative. The money value of time is central to inform decisions about: (i) whether to produce smaller aircraft aimed at direct services between secondary airports, or larger aircraft serving hub networks; (ii) whether to go for faster, more comfortable but more expensive regional jets versus turboprops; (iii) the extent to which engine technology should prioritise fuel-saving over speed; or (iv), and more innovatively, whether to invest in more expensive aircraft that fly closer to, or beyond, the sound barrier. The analyst may wish to enhance estimates of values of time readily available from governmental agencies with further analysis on the variance of recommended average estimates, particularly how values of time may change with income levels of different traffic segments. For example, the analysis of variance in values of time would be helpful when justifying investments in private aviation or in exploring the prospects for reintroducing supersonic commercial air travel.
The Challenge of Performing Research Which Will Contribute Helpful Engineering Knowledge Concerning Emergence
Published in Larry B. Rainey, Mo Jamshidi, Engineering Emergence, 2018
The existence of the phenomenon of emergence has been observed since ancient times and has been exploited in the practice of engineering throughout history. The history of the development of engineering knowledge until the rapid development of engineering and the parallel development of the sciences from the industrial revolution era was largely one of building according to known good practice with the occasional more ambitious project. From time to time an ambitious project would prove to have been too ambitious, with an ensuing disaster. The disaster often led to investigation and discovery of means to pre-empt a disaster of that class. Classically this pattern is recorded in the development of medieval cathedrals, but even in the “scientific” era of engineering of the past century there are many similar examples. A few, randomly selected examples include the Tacoma Narrows bridge failure, the collapse of the original box girder design of the Westgate Bridge in Melbourne, the loss of the first ancestor of the B-17 which proved too much for one pilot to handle, and the loss of several aircraft attempting to break the sound barrier. In each case additional research was done and means to successfully address the causal issues were found.
Higher-Order Linear Ordinary Differential Equations
Published in David V. Kalbaugh, Differential Equations for Engineers, 2017
When jet aircraft were first introduced military pilots flew trajectories similar to that shown in Figures 6.8 and 6.9 to minimize time to climb. Note that speed levels off when the aircraft is transiting through Mach 1 (the “sound barrier”). Recall the steep rise in drag coefficient at Mach 1 shown in Figure 6.5. Through advanced mathematical methods using a differential equation model very similar to the one we are employing here, including use of angle of attack as control, engineers found that a trajectory similar to that marked Trajectory II in Figures 6.10 and 6.11 was optimum and should greatly reduce time to climb. The dive midway in the trajectory assists the aircraft’s transit through the high-drag-coefficient region. Pilots were understandably dubious, but flight tests proved remarkably successful.
The transfer and exploitation of German air-to-air rocket and guided missile technology by the Western Allies after World War II
Published in The International Journal for the History of Engineering & Technology, 2020
Nevertheless, there were some scientific and technical shortcomings in the nascent German technology. The Anglo-Americans had a considerable lead in electronic warfare and microwave radio research, which had ramifications for German guided AAM development – the designers of the X-4 were forced to use a wire-link control system to prevent jamming of the radio frequencies. Also, the British plastic rocket propellants that were in development towards the end of the war (the propellant in the 5-inch LAP rocket was one such example) were superior in performance to German double-based solid propellants which consisted of nitrocellulose and diethylene glycol dinitrate as the principal constituents. But in the US and the UK, the technological evolution from aircraft cannons to rockets to guided missiles still had to be achieved. After the war, the American and British leap forward towards guided missile technology – with the aid of scientific and technical intelligence from Nazi Germany – became more complex as jet aircraft with greater performance and manoeuvrability were developed to reach and break the sound barrier.