AA Butterfly versus CNv LCD wind calculation

The Air Avionics Butterfly has developed an outstanding reputation as having a competitive advantage for its ability to "instantaneously" calculate wind direction.

Does the CNv (with latest 3.3.3899 or beta 3.4.4089) calculate wind as quickly as the Butterfly?

T8, what is the wind direction update rate of the CNv?

If anyone has experience using both varios at the same time, please share your opinions.

On Friday, 16 September 2016 21:23:48 UTC+1, wrote:
The Air Avionics Butterfly has developed an outstanding reputation as having a competitive advantage for its ability to "instantaneously" calculate wind direction.

Does the CNv (with latest 3.3.3899 or beta 3.4.4089) calculate wind as quickly as the Butterfly?

T8, what is the wind direction update rate of the CNv?

If anyone has experience using both varios at the same time, please share your opinions.

And how do the LX Nav varios compare? I have LX9000/V9. I am impressed by the way it shows me wind changing with height as I climb in wave etc.

On Friday, September 16, 2016 at 4:36:01 PM UTC-7, waremark wrote:
On Friday, 16 September 2016 21:23:48 UTC+1, wrote:
The Air Avionics Butterfly has developed an outstanding reputation as having a competitive advantage for its ability to "instantaneously" calculate wind direction.

Does the CNv (with latest 3.3.3899 or beta 3.4.4089) calculate wind as quickly as the Butterfly?

T8, what is the wind direction update rate of the CNv?

If anyone has experience using both varios at the same time, please share your opinions.

And how do the LX Nav varios compare? I have LX9000/V9. I am impressed by the way it shows me wind changing with height as I climb in wave etc.

Unfortunately that tells us nothing about how accurate the real time wind calculation is. I have flown with the Butterfly vario for 2 seasons now and can say that the wind accuracy is good, but sometimes goes bonkers (off by 10 kt or more). I monitor while circling and can compare it to my track over the ground. I have also set up the Butterfly to display both true airspeed and GPS ground speed. The difference is the head/tailwind component. I can compare that to the real time wind vector for a sensibility measure.

Tom

Respectfully, please keep comments focused to OP. The question does not address the LX products which are outstanding IMHO.


And how do the LX Nav varios compare? I have LX9000/V9. I am impressed by the way it shows me wind changing with height as I climb in wave etc.

I own a CNv and installed the latest software updates. I also have experience with an Air Avionics Butterfly. But I did not use both varios at the same time.

CNv wind calculations became quicker during the various releases. But in my opinion, it is still slower and less reliable compared to a well compensated Butterfly vario. You will notice the difference especially when flying straight.

The Air Avionics system has a much higher resolution of small wind changes compared to the CNv and it does not need changes in direction for wind updates. But you need to spend some time in setting up the Butterfly sensor unit until it works well. If you did so, it can be very helpful to find lines of lift. I find CNv wind speed calculations sometimes to be inconclusive (too high), but perhaps this is related to my setup.

On Saturday, September 17, 2016 at 5:12:54 PM UTC-4, wrote:
I own a CNv and installed the latest software updates. I also have experience with an Air Avionics Butterfly. But I did not use both varios at the same time.

CNv wind calculations became quicker during the various releases. But in my opinion, it is still slower and less reliable compared to a well compensated Butterfly vario. You will notice the difference especially when flying straight.

The Air Avionics system has a much higher resolution of small wind changes compared to the CNv and it does not need changes in direction for wind updates. But you need to spend some time in setting up the Butterfly sensor unit until it works well. If you did so, it can be very helpful to find lines of lift. I find CNv wind speed calculations sometimes to be inconclusive (too high), but perhaps this is related to my setup.

Great opinions...thanks for contributing. Keep them coming.

On Saturday, September 17, 2016 at 4:38:17 PM UTC-7, wrote:
On Saturday, September 17, 2016 at 5:12:54 PM UTC-4, wrote:
I own a CNv and installed the latest software updates. I also have experience with an Air Avionics Butterfly. But I did not use both varios at the same time.

CNv wind calculations became quicker during the various releases. But in my opinion, it is still slower and less reliable compared to a well compensated Butterfly vario. You will notice the difference especially when flying straight.

The Air Avionics system has a much higher resolution of small wind changes compared to the CNv and it does not need changes in direction for wind updates. But you need to spend some time in setting up the Butterfly sensor unit until it works well. If you did so, it can be very helpful to find lines of lift. I find CNv wind speed calculations sometimes to be inconclusive (too high), but perhaps this is related to my setup.

Great opinions...thanks for contributing. Keep them coming.

I've had both Air and CNv for a year or so now.
The wind display from the Air is amazingly fast. Yes, it changes a lot but so do conditions. The most incredible display of wind is while flying lines of convergence.
While the CNv wind display refreshes much faster in the latest version, the wind itself does not update. Attributed to the difference between using the inertial sensors or not.
But the CNv does an excellent job in choppy thermals.
Jim

On Friday, September 16, 2016 at 4:23:48 PM UTC-4, wrote:

Does the CNv (with latest 3.3.3899 or beta 3.4.4089) calculate wind as quickly as the Butterfly?

No.

T8, what is the wind direction update rate of the CNv?

I don't have a quantitative answer here. Mostly it depends on your flight path. CNv depends on some GPS track variation for vector wind calculation, but it doesn't take a great deal (20 degrees total track seems to do it in most cases). Given sufficient GPS track variation, the fast wind seems to update in just a few seconds ( 10). The auto wind is slower, gives a more stable number. It seems to take a few tens of seconds to update. Either mode is noticeably faster than previous generation flight computers (302, SN-10B). I haven't flown the Butterfly vario. The component head/tail wind is updated very fast (less than a second).

The only difference between "auto" and "fast" winds in CNvXC is the time constant. I see no downside to the fast wind, so I've been lobbying to make this the default. The fast wind is excellent for close in mountain flying.

best,
Evan / T8

On Friday, September 16, 2016 at 1:23:48 PM UTC-7, wrote:
The Air Avionics Butterfly has developed an outstanding reputation as having a competitive advantage for its ability to "instantaneously" calculate wind direction.

Does the CNv (with latest 3.3.3899 or beta 3.4.4089) calculate wind as quickly as the Butterfly?

T8, what is the wind direction update rate of the CNv?

If anyone has experience using both varios at the same time, please share your opinions.

The Air Vario updates the wind once a second and calculates it much more often than that.

When I first began using it, I was skeptical, but have come to pretty much believe what it says. Every time I thought it had a surprising value, in any situation I could confirm, it was correct. I have discovered convergence lines, shear lines, and wave using it. I have also discovered some local weather patterns which can be exploited, no one else seems to know they are there nor did I, until the Air Vario.

I thought accurate straight line glide computer wind accuracy required a fixed compass (aka LXNAv) for the best not thermaling wind detection sensitivity. My S10 is going to have a compass module shortly. But I really can't imagine a need that that much wind accuracy. The wind where you are now isn't the problem. It's accurate anticipation of what the wind is 1, 5 10 and 20 miles ahead, just like sailing, but much less critical.

Am I right or wrong on the compass module?

I believe the butterfly an fixed compass built in, and this is the reason that it is more energetic on updates? Correct?