Chopper crash

Kevin: There is a section in Prouty where he reports on a series of tests
conducted at Cal Poly that claimed to demonstrate no change in hover power
required over water. I've put that in the magazine once and received a
bunch of howls from helo pilots claiming other wise. The Cal Poly guys did
have some instrumentation with numbers to support their argument.??

--
Stuart Fields
Experimental Helo magazine
P. O. Box 1585
Inyokern, CA 93527
(760) 377-4478 ph
(760) 408-9747 publication cell
"The OTHER Kevin in San Diego" skiddz "AT" adelphia "DOT" net wrote in
message ...
On Mon, 15 May 2006 21:14:51 GMT, "Steve R"
wrote:


I know nothing about operating an aircraft off of water like that but I
thought it strange how far he put the nose down in his attempt to lift
off.
I'd imagine that he was trying to achieve ETL but really?? He buried the
nose, all the way over the windshield, "under" the surf. Once that
happened, it's no surprise that he didn't have enough power to pull out,
or
cyclic authority to level the ship.

Water will dissipate the downwash- kinda like "sorta ground effect".
Same with tall grass.. The water ops I've seen always had the heli
make a vertical pickup to a hover, then a normal takeoff.. I have to
wonder if dumping the collective when the water started coming over
the cockpit might have saved the heli.

The pilot definitely made screwed the pooch on that one. The real tragedy
is that someone had to die because of it.

I think the pilot was the one who died...

Kevin: There is a section in Prouty where he reports on a series of tests
conducted at Cal Poly that claimed to demonstrate no change in hover power
required over water. I've put that in the magazine once and received a
bunch of howls from helo pilots claiming other wise. The Cal Poly guys did
have some instrumentation with numbers to support their argument.??

Nice that somebody mentions!

"Mike Baker and Jonathan Scarcello made ground effect measurements over
astroturf and over water. The astroturf results tend to refute the
pilots' observations. The ground effect at half a rotor diameter was
roughly 30% stronger than over the smooth solid surface. Over water,
however, there was _little_ measurable difference"

Prouty in "More helicopter aerodynamics" Chapter 2.

I got kicked in the ass on mentioning that towards some of my CFIs.
And I noticed that I need little more power in hover over tall
grass/bushes. However, that's not astroturf.
I never hovered over water.