View Single Post
  #85  
Old September 12th 03, 05:57 AM
Mike Marron
external usenet poster
 
Posts: n/a
Default

(Peter Stickney) wrote:
Mike Marron wrote:


Not to mention the Superfort's extra *4,000* total horsepower and four
humongous four-blade 17-ft. diameter props!


Seems that this has come up before. Actually, no, the extra power
really down't enter into it.


Cruise (Max L/D) occurs at the Equivalent Airspeed where the drag is
at a minimum. This occurs at the point where the Induced Drag, which
is decreasing as the speed increases(4th root of EAS), and the Profile
Drag, which is increasing with the square of the EAS. That's the
point where the minumum amount of thrust/power to keep flying occurs.
Note that the amount of installed power doesn't enter into it at all.


High power is useful, however, for times when more power than that
requiring maintaining cruising flight is important, such as when
climbing, or for takeoff, or maneuvering flight.


Interesting stuff. So lemme get this all straight: if you removed and
replaced the B-29's four R-3350's with R-1830's, that would NOT
reduce the cruise or top speed and although the Shackleton dropped
bombs from time to time it was NOT a bomber and the variable
incidence wing on the F-8 did NOT to enable it to maintain the slower
speeds necessary for carrier landings and the flat, raised portion of
the wing assembly directly above the F-8 fuselage did NOT serve
as a speed brake. Gotcha...

-Mike (mucho gracias!) Marron