Re: fudge factor question

From: Don Slusarczyk <don5490_at_sbcglobal.net>
Date: Mon, 23 Jan 2006 17:46:58 -0500

Mark,

Since you posted here I will answer here.

I dont recall ever hosting a ministick postal in the past so not sure
where Jeff got that one from . If Jeff said I made it then I can dig in
and tell you how I calculated it. I recall at one time graphing the
ministick postal flight times vs ceiling height and may have adjusted
the constants that Bud Tenny created to fit a ministick better than the
factor use to be. I recall that a 22 minute ministick flight in 120 feet
would be beaten by a 6 minute flight in 8 feet. I thought that was
wrong. The other linear fudge factors are the ones I used for years for
the other events and are based on actual flight results and a
compilation of contest results and current AMA records. I graphed them
and found a rough linear relationship for ceilings less than 60ft and
that is what I used. Very rarely did a person fly in a postal in a
ceiling higher than about 50 feet.

The EZB factor was determined during the USA vs Japan postal. Having
flown a lot of Cat I EZB at the time, I knew how long a flight would
last based on the time it touched the ceiling last. If I scrubbed for 15
minutes then I would get a 20 minute flight. If I scrubbed for 12 I got
17. It was always 5 minutes for a 20 foot drop. So in a 10 foot site the
model still scrubbed for 15 minutes, but only got 2 more coming down. So
a 17 minute flight in 10 feet equaled 20 in a 20 ft site. A 1 ft site
would get 16 minutes. That is the logic I used . If a HLG drops one
second per foot, and the ceiling is 10 feet higher, you can expect in
reason that the flight time will be about 10 seconds higher (plus a
little more for climb). That is the math and reason behind it. I felt it
better to customize the fudge tp each event instead of the universal
blanket factor which is plain wrong but was used so many years. You may
recall in the past I used to make the fudge factor about half way
through the postal once flight times were entered for new events. There
is no way to equate it exactly, you can then argue for fudge factors for
altitude and temperature, then you go crazy. I figured used real flights
and graphng it and seeing what fell out was the best approach, and I
will say I think they are close based on past postals and how close they
have been in the past. Especially on HLG and CLG, the competition was
great the past few years, guys squeezing in the extra few tenths to get
the high time. That told me the factors were good. I never had to deal
with competative high ceiling height flight times in any of the postals.
Most guys are in a 20 to 30 ft gym. Not a 150ft hangar. So I am not sure
if the linear factors hold up for sites like USIC.

Hope this helps.
Don

.

> Don, I understand you provided the fudge factor formulas for the postal
> contest now hosted on Indoornews.com.
>
>
>
Received on Mon Jan 23 2006 - 14:50:49 CET