As far as missouri is concerned, here is the rule from
http://www.boat-ed.com/mo/handbook/index.htm




Skier Down Flags
A flag indicating a "skier down/person in the water" is required
equipment for a motorboat (other than a PWC) towing a person behind on water
skis, inner tubes, sleds or similar devices. This flag is to be displayed
when the person is in the water before or after being towed on water skis or
similar devices or when a swimmer leaves the confines of the vessel.
Displaying of the flag is required from 11:00 AM to sunset and is effective
only on the Mississippi River, Missouri River and the lakes of this state.
The color of the flag must be either red or bright orange.
The flag must be square in design and measure at least 12 inches on
each side.
When displayed, the flag must be visible for 360 degrees.
All vessel operators in the vicinity of a displayed skier down flag are
required to operate at idle speed if closer than
50 yards to the vessel displaying the flag. It is suggested, when
operating in the vicinity of a displayed skier down flag, that operators
immediately start scanning the water for the downed skier.
Skier Down Flag
A rectangular orange or red flag, at least 12 inches by 12 inches

All vessel operators are encouraged to maneuver away from the area in
which a ski flag is being displayed.
This flag is to be displayed only when the skier (or person being towed
on inner tubes, sleds, etc.) is in the water before or after being towed.
Once the skier is up and being towed, the flag must be lowered. The flag
must be raised again when the skier falls or stops skiing and enters the
water in order to return to the motorboat.
PWC and moored or anchored motorboats are exempt from displaying the
skier down flag.


--
Steve (here to have fun) Barker

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Remove the not dot from my address to abuse my email box
"Rural Knight" wrote in message
nk.net...
Is the flag displayed while towing the skier?

"CraigM" wrote in message