Dr. Kaveh Azar quotes1-2 Quotations of 2
I advise engineers to start by performing first-order calculations to see where a heat-transfer problem lies. You can quickly estimate the heat-transfer answer to within 20 percent to 30 percent. After you have a first-order solution, use computation or experimentation to perform another, independent analysis, but do not use results from the first-order solution as boundary conditions. You want two independent answers.
~ Dr. Kaveh Azar
All our recent initiatives are very successful because they answer to what our customers are telling us they want and that is a more comfortable, enjoyable flying experience, ... If other airlines like American do not realize that this is important to fliers – especially the most frequent flyers – then they must not be listening to their customers as closely as we are.