Netto bis

[bish]

Hi
When I set my Lx 7000 to Netto, my vario needle indicate +1.8 kt on
the ground.
When I choose vario or relative vario the needle indicate 0.
Why is that?
Thank you,
Gilles

[Dave Hoppe[_2_]]

On 8/13/2011 3:25 PM, bish wrote:
> Hi
> When I set my Lx 7000 to Netto, my vario needle indicate +1.8 kt on
> the ground.
> When I choose vario or relative vario the needle indicate 0.
> Why is that?
> Thank you,
> Gilles


Because it's adjusting for your sink rate. On the ground you're not
sinking. If you were flying the sink rate adjustment should have your
needle at zero.

[Dave Hoppe[_2_]]

On 8/13/2011 3:45 PM, Dave Hoppe wrote:
> On 8/13/2011 3:25 PM, bish wrote:
>> Hi
>> When I set my Lx 7000 to Netto, my vario needle indicate +1.8 kt on
>> the ground.
>> When I choose vario or relative vario the needle indicate 0.
>> Why is that?
>> Thank you,
>> Gilles
>
>
> Because it's adjusting for your sink rate. On the ground you're not
> sinking. If you were flying the sink rate adjustment should have your
> needle at zero.
>


In calm air with appropriate polar information entered.

[Mark Burton]

On Aug 13, 9:25*pm, bish > wrote:
> Hi
> When I set my Lx 7000 to Netto, * my vario needle *indicate +1.8 kt on
> the ground.
> When I choose vario or relative vario the needle *indicate 0.
> Why is that?
> Thank you,
> Gilles

Mine does the same. I assume that it is because it does not realise
you are not flying, and the sink rate at minimum flying speed would be
about 1.8 knots; since you are not descending, it thinks you are in
air which is rising at 1.8 knots.

This is what I have always believed, but it is just a guess on my
part. I like netto mode for the cruise.

Mark Burton

[Heinz]

The LX7000 in NETTO-mode is trying to compute what the air around you is doing.

Since your ship's (Computerized)polar tells the LX that it it should be sinking at 1.8 kt and the Vario information tells the computer that is is at zero sink, it tells you that the "airmass" around the ship is moving up at 1.8k.

Note that once you have some airspeed (above the point where the polar-curve makes sense), the LX will take the sink at that speed from the polar and compare that sink to the Vario-indicated sink to compute air vertical motion.


Heinz