© Flytec USA, 2003
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numbers on a black field). It is now possible to make goal by leaving the thermal at that point, and flying at the
optimum speed to fly speed. This assumes that there is no net lift or sink on final glide into goal. Of course, it
depends on the pilot’s confidence, of the conditions of the air mass on the way to goal, as to whether or not he/she
decides to leave immediately when a positive
Alt. a. WP
is displayed, or to continue to climb for some reserve
altitude. Naturally, the 5030 does not know whether the net lift or sink will be zero, or whether the wind will change. It
takes into account the present wind and assumes that no rising or sinking air masses will be encountered.
Gliding to Goal
Since the height needed to attain optimum final glide speed is based on the strength of the last thermal, the pilot
should control his/her speed on final glide so that the McCready pointer lines up with Average Thermal Climb
indicator. If a large area of sink is encountered, you will likely have to fly slower with a lower McCready indicator value
(of course after you clear the sink). Under no circumstances should you allow the McCready arrow to go below zero.
Other valuable data should also be monitored such as your altitude over your best glide line (
Alt a. BG
) and required
L/D (
L/D req.
)
If you leave a good thermal when the with
Alt a. WP
reaches zero, this means that you have climbed to an altitude
appreciably higher than that required to make goal at best glide speed. This extra height will allow you to glide to
goal at a higher speed. However, if the average lift in the last thermal is weak, the unit calculates a glide speed that
is just a little more than the best glide speed. Therefore there would only be a minimal extra altitude and a small area
of sink could prevent you from reaching goal without another thermal. For this reason you should climb to an altitude
higher than
Alt a. WP
= 0 if your last thermal is weak.
E7 Total Energy Compensation (TEC)
The pilot converts kinetic energy into height by pushing out. Conversely, the pilot converts the altitude or potential
energy into speed by pulling in. His/her total energy (kinetic plus potential), discounting friction, remains constant.
If an obvious gain in altitude can be achieved by excess speed reduction, the use of TEC makes sense. A hang
glider can gain 60 or more feet of height when pushing out the control bar at high speed. It would be a mistake if this
altitude gain were interpreted by the pilot as lift. The 5030 can suppress these vario swings caused by speed
changes, and will indicate climb or sink caused by the surrounding air, and not by the conversion of speed to altitude.
When flying according to speed to fly, where speed adjustments are continuously necessary, the TEC is of great
help. The TEC also steadies the sounds and vario when centering in a turbulent thermal. The effect of the TEC can
be adjusted in Menu>Basic Settings>TEC
.
We recommend values between 60 and 80%. Complete control (100%)
has not proved useful, because even horizontal wind turbulences can influence the TEC and make the vario a bit
jumpy.
E8 New Regulation for Record Flights or Decentralized Competitions
Since the proof of a completed flight depends entirely on the GPS recording, it is important to ensure that the GPS
receiver has good satellite reception before take off. The 5030 should be turned on several minutes before take off to
help insure that the GPS is full acquired. Please also read section C2 -Flight Memory and Flight Analysis.
A barogram is also included in the recorded IGC data of each flight. Photographic proof and confirmation by flight
observers are no longer required for national performance flights. The data can be sent directly to the judging
committee via the Internet. See section D1 Data Exchange Via PC.
E9 Proof of Flights - Security against Manipulation
The FAI (Féderation Aéronautique Internationale) and its subsidiary, IGC (International Gliding Committee), requires
a recording format, which, besides the continuous recording of time, and position, also includes the flight altitude. In
so doing it, replaces the standard barograph. When transmitting flight data to the pilot’s PC, an IGC file is created,
which includes a digital signature authenticating the flight data, making the file fraud proof. If only one bit in the flight
data were changed, the signature would no longer correspond, and the judging committee would be aware of the
manipulation. Starting with firmware version v2.21 the takeoff and landing point are now written in the IGC file. The
take off position is the lat/long position where the instrument recognizes a flight (10km/h true airspeed or GND speed
