LOT Polish Airlines Flight 7 increased engine wear, since the engines were under greater load. NK-8-4 engines were not reliable enough. Warranty service life was only 5000 hours, and about half of LOT engines failed after 2000–3000 hours. Because of this, Polish pilots often called the Il-62 "flying coffins". In spite of the low reliability, the airline decided to increase overhaul life intervals to reduce the frequency of repairs, which were carried out in Soviet factories and quite expensive. LOT sent a letter to the Ilyushin Design Bureau containing the results of a test in which it was found that the engines could operate normally
Brand equity superior and which strong, favorable, and unique brand associations should exist in consumers' minds. Both of these issues - brand meaning in terms of products, benefits, and needs as well as brand meaning in terms of product differentiation - depend on the firm's general approach to product development, branding strategies, and other strategic concerns. Any new development in the marketing environment can affect a brand's fortune. Nevertheless, a number of brands have managed to make impressive comebacks in recent years. Often, the first thing to do in revitalizing a brand is to understand what the sources of brand equity were