Dimples On Model Aircraft Could Greatly Extend Range

On 9 Nov, 23:22, "Highflyer" wrote:
"Gregory Hall" wrote in message

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| * * * * * I've noticed that when we paint an airplane with the really
| shiny smooth urethane paints, it seems to lose a little cruise speed.

Depending upon the size of the aircraft paint can add a considerable
weight burden. However, when the paint is really smooth it can drag along
with it an increasingly thicker layer of turbulent air building toward the
aft end of the aircraft. Dragging this thick turbulent boundary layer
causes increased drag which seems counter-intuitive to smoothness. This is
why various small surface patterns (seems to me somebody should try
fractals) often decrease drag - they decrease the extent of the turbulent
boundary layer thus the drag caused by it.

--
Gregory Hall

During WWII they decided to repaint the Spitfire with a flat matt finish
paint so it would be harder to see at night.

Eh?
Virtually all RAF combat aeroplanes in WWII were painted in a matt
finish. Why on earth would you paint a Spit so it was hard to see at
night? They did not fly at night - or do you have loads of pics of
Spits in a matt black finish?

Guy
SNIP