View Single Post
  #11  
Old August 12th 03, 05:41 PM
Bob Johnson
external usenet poster
 
Posts: n/a
Default

!doctype html public "-//w3c//dtd html 4.0 transitional//en"
html
Hi Chris --
pDue to the high 0.45 USD cost of the stuff, I agree that a careful look
should be made of the rollers, etc. that an existing winch is equipped
with. The photos of our winch on the PSA web site shows the care that has
Craig put into his design. Two large diameter, grooved aluminum sheaves,
running in permanently lubed bearings are set opposed in a close-fitting
housing. Two vertical rollers are arranged to handle cross-wind side loads.
The entire sheave/roller element is free to rotate in sleeve bearings in
the vertical plane in order to keep the pull as uniform as possible. The
narrow  6-inch wide, large diameter drum eliminates any need for a
level-wind, or as you call it, pay-on gear.  
pIt's been my observation that the upper sheave receives most of the
action during climb to release and the lower sheave, as you would expect,
comes into play on the pull-back. The rollers work really well during chute
retrieve, since the wind is seldom exactly favoring. Speaking of the retrieve,
I find that the chute "flew" somewhat better with steel than it does with
Plasma, which is certainly not what I was expecting. 
pAs for the guillotine, we're still working on that one. The 1320-lb.
"Blue" Tost weak links we are using seem to let go easily when the Blanik
encounters a thermal just prior to release, so this is some consolation,
at least.
pAt the risk of splitting the threads, I would like to make the observation
that the unique Blanik bridle tow system allows us to advance the throttle
of our 325-hp engine smartly to the limit on the start, with no complaints
from the flying end of the rope as to "pitch-up" or excessive G's for that
matter . Of course, the throttle has to be just as smartly retarded to
keep things running at about 3500 engine rpm and 410 drum rpm to maintain
a 55 kt climb to transition to release.
pI have no Blanik or Plasma financial interest, but I must confess attempting
to find Cortland's stock ticker symbol.
pBJ
pChris Nicholas wrote:
blockquote TYPE=CITEDo any changes have to be made to the pay-on rollers,
to avoid the
brlighter rope slipping and potentially overheating locally?  On
our
brwinch, the rollers are heavily scored where generations of steel cable
brhave slipped a bit and cut into the surface.
pThese rollers are now about 40 years old, maybe older.  While they
could
brperhaps be renewed with a good surface, they do have considerable
brinertia, and a free-running cable suddenly coming into contact with
one
brof them is bound to take some time to whirl it up to speed.  Steel
brstands up to that - would Spectra/Dyneema?
pChris N./blockquote
/html