SEN-413 May 4 2000
- Category: Archive 2000
- Hits: 290
News and Reports 2000 - First half
SCAT Electronic News 4 May 2000 issue 413
Table of Contents
AIR - O'Dwyer
GPS - Abad
Questions from a kiwi who couldn't make it to Omarama - Magill
SCAT Annual Results ? - Cowley
Fred's Weather Question - Biggles
GPS - Van Wallene
Photographic tips - Gregorie
In the tires! Don , maybe you should switch to photography. Those were
very sharp pictures you sent to SEN.
After arriving at a contest with a flat tire on my bike and borrowing
a can of the pressurized sealant stuff from Russ Snyder several years ago,
I always carry a can in the spare tire well. Sorry I didn't know.
Good news for better model retriving?
Top Headlines from AVweb's NewsWire
U.S. MILITARY STOPS DEGRADING GLOBAL POSITIONING SYSTEM ACCURACY...
With the "flick of a switch" at the Air Force Space Command this week,
your GPS navigation box just got better. As of midnight GMT on Monday,
the Department of Defense turned off selective availability (SA), the
intentional degradation of the GPS signal that has been supplied to
civilian users worldwide. Instead of a 300-foot accuracy, civil GPS
users can now expect accuracy to within 100 feet or better. No changes
are necessary in anyone's GPS nav boxes to take advantage of the
improved signal. Immediate benefits to aviation users include better
situational awareness on the ground at airports while taxiing, and more
reliable performance from GPS-based terrain avoidance systems while in
the approach and landing phase.
..."SA" TURNED OFF, BUT THEY CAN TURN IT BACK ON FOR THE BAD GUYS...
The discontinuation of SA was made possible by the development of
techniques that allow the military to restore the intentional
"dithering" of the timing signal on a regional basis, when required by
national security concerns. This would effectively deny the increased
GPS accuracy to unfriendly users in that particular area. Arthur Money,
assistant secretary of defense, was intentionally vague about how the
regional degradation system would work in times of crisis, but did say
that if the improved GPS signal were denied to a region such as the
Balkans, that users in Athens or Frankfurt would not be affected.
Questions from a kiwi who couldn't make it to Omarama
Hello Roger, my name is Jason Magill,(you may have heard of father my
father Ron) and i'm an F.1.A flier from New Zealand, unfortunatly i
couldn't make it to Omarama, so i missed out on Victor's seminar. I have a
few questions, am already registered to S.C.A.T news, and am not sure how
to ask them in the chat forum. Since i have lost/damaged my two best
gliders recently, i'm building some new ones, and i'm trying to find ways
of reducing the building time of them. My questions are about wing ribs(
cause i detest cutting em out):) I have asked several people who were at
Omarama, and i found they all seemed to have different recollections on how
Victor made his ribs. I have made a form with the bottom rib camber in it,
and made a sample lamination with lotsa layers of 1/32 sheet, stuck with
p.v.a, just to see what it would come out like... what i would like to know,
is how many laminations of what thickness balsa does Victor use?, what
glue does he use?, how does he clamp the laminations down to the form?, and
finally how does he cut them up?. Failing this, i'd really like to know
what methods people use to make their ribs, i think i saw somewhere that a
guy said to make up rectangles of balsa, and hold them together with lengths
of bicycle spoke..hrmm, the only bicycle spoke i've seen here is too thick
for going through the rear of of your typical modern glider section..and it
seems like if you only hold the rib stack at the front, ther'es nothing to
hold the rear of the stack still while sanding em, hrmm, or maybe the guy
uses a real thick airfoil! I don't know about you, but i gave up trying to
cut em round a template while the ends of my fingers were still
there..heheh, anyway, i'd really appreciate some info on the subject, oh,
and also i'd like to correspond with other F.1.A flyers from anywhere, so
we can maybe swap some ideas..., looking forward to hearing from you,
*please note the two underscores after wheels!:)
SCAT Annual Results ?
* Please publish the following:
Check your Glassware Collection:
* We are trying to create a complete listing of results for the SCAT
Annual (which don't ever seem to have been published ?), which took over
from what was formerly the Max Men Annual, so that we can complete the
newly donated event trophies for F1G, F1H and F1J.
* Missing years are 1990, 1991, 1995 and 1996 =AD so please check your
glassware collection or other sources of historical data and contact us
if you think you can lay claim to any of these particular events and
Fred's Weather Question
* In answer to Fred's weather question, I find the best site is via
Paul Trist's Planes Wings and Things web site links:
* Start at "Lost Hills" link and then enter "Rancho Cordova, CA", or
whichever contest site you are interested in.
* Paul sells mainly R/C Glider stuff, but his Shiny tape is good for
Maybe some interesting news for all GPS lovers.
I just read in the paper that Mr Clinton banned the use of deliberate
GPS errors for defense purposes. This means that as from yesterday, all
GPS units will have a ten fold better accuracy. This error used to be
about 100 meters, so now it should be 10 meters or better.
To get optimum model tracking results, it might be best to use an
accurate map with visualized landmarks. Pinpoint the launch site, and
the landmark (if any) the model is heading for. The GPS is then used to
extend this bearing to infinity. Just follow the arrow on the GPS
display and be carefull not to run the model over!
Good hunting, Allard
[Allard - why so simple ?
How about the GPS on the airplane to radio to you with it's
coordinates ... or on the airplane to tell time
the flight. When the plane stops moving as detected by the gps it's down.
Or to use to instrument the flight as the GPS can measure
altitude as well x/y position. ... And a GPS has to be OK
because the sergant-at-arms of Team Luddite has one ! ]
I've noticed that the brightness and contrast of digital camera snaps and
scanned images produced by myself as well as others are often not as good as
they should be. I hope the following tips will help my fellow sportsmen to
make clearer digital pictures of contests and models.
The main problem with digicam shots is that the automatic exposure controls
often give an incorrect brightness and, in some conditions, the contrast is
wrong too. In this a digital camera is like using slide film; what the
camera chose is what you get. This is unlike shooting prints, where exposure
errors on the negative are largely corrected by the colour printing machine.
The viewfinder on almost all cameras shows a little less of the scene than
will appear in the photo so theres often a need to correct the framing of
the picture and to correct those shots where you thought the camera was
level but it wasn't or the page wasn't straight in the scanner.
Fortunately, there is a way to fix both digicam and scanned images on your
PC. Almost all cameras and scanners come with a free image editing program.
This is usually Adobe Photoshop. If yours didn't come with one or you hate
Photoshop, then you can pick up a copy of L-View Pro or PaintShop Pro (why
is there no PaintShop Amateur?) fairly inexpensively off the Net. For ease
of use and cost reasons I prefer L-View for fixing
Whenever I've downloaded shots from my digicam I pull them straight into
L-view and fix the brightness (exposure), which is often too dark. More
rarely I may fix the contrast as well, but this is usually only needed for a
flash shot. Doing these two things gives about a 200% improvement in the
picture. You can see faces shaded by hats for starters.
Following this, I'll probably use cut and paste to get rid of all the boring
surroundings and correct for the off-centre chip in my camera. If I held the
camera crooked I'll use the 'rotate' tool to stand things upright. Finally,
if the image is a little fuzzy (my camera's autofocus isn't brilliant), I
may try the 'sharpen' filter.
I hope this hasn't been preaching to the choir and that it will inspire you
to experiment with the colour correction and filter tools in your image
display program. I also hope you'll enjoy the results and have fun doing it.