Operation Manual

V3 Version 1.0 November 2012
Page 21 of 29
6 Variometer and Altimeter
All signals from the pneumatic sensor (altitude) is derived from high quality pressure sensor
which mean that no flask is necessary. The vario signal is derived from the altitude signal.
Altitude sensor has temperature compensation. Mechanical needle and colour display show
the vario information as well as many other parameters.
The display is user configurable. The variometer can be configured to show:
• Range 5, 10 and 2.5 m/s or 10, 20 and 5 kts.
• time constants 0.1 s to 5 s, in addition there are 4 settings for electronic processing
for the vario signal.
Vario indications can be corrected for total energy with a TE probe. The quality of the TE
compensation depends entirely on the location, size and dimension of the TE tube. The
installation must be leak-proof.
Compensation with TE probe
6.1 Altimeter
The altimeter of the LXNAV V3 is temperature compensated from -20ºC up to + 60ºC. The
altimeter is calibrated up to 20000 m.
6.2 Speed to fly
Speed to fly is based on the MacCready theory is a very useful tool to optimise cross-country
speed. The pilot must follow Speed to fly value on pneumatic airspeed indicator. Speed to
fly is calculated from polar of glider, actual sink rate (vario), MacCready setting, Ballast and
Bug setting.
TE (Pst)
LXNAV V3