Date: 15 Apr 97 03:22:43 From: Chuanga@cris.com (H Andrew Chuang) Organization: Concentric Internet Services References: 1
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In article <airliners.1997.910@ohare.Chicago.COM> john r. (firstname.lastname@example.org) wrote: > > Can anyone give me some approximate guidelines to compare jet engine > thrust and rotating shaft power. power = force x velocity Thus, 1 lb thrust @ 375 mph (or 550 ft/sec) is equivalent to 1 shp. > We were recently looking over The Queen Mary at Long Beach and in the > engine room it said that the four turbines produced about 260,000 horse > power between them. About as much as a modern Jumbo I said but was > greeted with disbelief. > > Was I that far out ? Well, pardon my ignorance. How fast can (or could) the Queen Mary travel? 40 kts perhaps? If so, then the equivalent thrust at cruise will be: 260,000 * 375 / (40 * 1.15) ~ 2,200,000 lbf The total thrust of a B747 with four PW4056 engines is 224,000 lbf. Nevertheless, I do not think the thrust comparsion of two objects moving at very different speeds is meaningful.