Electronic vs. Pneumatic TE

[SoaringXCellence]

Just got a LX V7 and was wondering about opinions regarding the TE function. I have a pneumatic TE in the glider, but was just wondering if the electronic might be better.

The whole TE concept is really a mathematical process and if the unit has a good Pitot and Static source it should be able to get the TE without a probe, just by calculation.

I've had false reading with some pneumatic system due to yaw (poor coordination, I know), which the electronic system may be able to avoid.

What's your opinion?

[[email protected]]

W dniu poniedziałek, 9 czerwca 2014 07:49:33 UTC+2 użytkownik SoaringXCellence napisał:
> Just got a LX V7 and was wondering about opinions regarding the TE function. I have a pneumatic TE in the glider, but was just wondering if the electronic might be better.
>
>
>
> The whole TE concept is really a mathematical process and if the unit has a good Pitot and Static source it should be able to get the TE without a probe, just by calculation.
>
>
>
> I've had false reading with some pneumatic system due to yaw (poor coordination, I know), which the electronic system may be able to avoid.
>
>
>
> What's your opinion?

many years ago i made such analog device for hang-glider based on speed (propeller fan) and hang-glider loads (transfer kinetic and geopotential energy)
and compensation worked well
sensitiveness was about 10 cm/s

[7C]

On Monday, 9 June 2014 06:49:33 UTC+1, SoaringXCellence wrote:
> Just got a LX V7 and was wondering about opinions regarding the TE function. I have a pneumatic TE in the glider, but was just wondering if the electronic might be better.
>
>
>
> The whole TE concept is really a mathematical process and if the unit has a good Pitot and Static source it should be able to get the TE without a probe, just by calculation.
>
>
>
> I've had false reading with some pneumatic system due to yaw (poor coordination, I know), which the electronic system may be able to avoid.
>
>
>
> What's your opinion?

My experience how well your pneumatic TE depends a lot on the instruments you connect to it. I had a lot of trouble with an LX160 and a Winter connected on the same line. Removing the Winter and replacing it with a Borgelt resolved the issues nicely. (Flow vs Pressure sensing)

I would guess that if you want a flow unit as well as your new LX then you may be better using electronic compensation.

Mel

[s6]

Le lundi 9 juin 2014 03:18:28 UTC-4, 7C a écrit*:
> On Monday, 9 June 2014 06:49:33 UTC+1, SoaringXCellence wrote:
>
> > Just got a LX V7 and was wondering about opinions regarding the TE function. I have a pneumatic TE in the glider, but was just wondering if the electronic might be better.
>
> >
>
> >
>
> >
>
> > The whole TE concept is really a mathematical process and if the unit has a good Pitot and Static source it should be able to get the TE without a probe, just by calculation.
>
> >
>
> >
>
> >
>
> > I've had false reading with some pneumatic system due to yaw (poor coordination, I know), which the electronic system may be able to avoid.
>
> >
>
> >
>
> >
>
> > What's your opinion?
>
>
>
> My experience how well your pneumatic TE depends a lot on the instruments you connect to it. I had a lot of trouble with an LX160 and a Winter connected on the same line. Removing the Winter and replacing it with a Borgelt resolved the issues nicely. (Flow vs Pressure sensing)
>
>
>
> I would guess that if you want a flow unit as well as your new LX then you may be better using electronic compensation.
>
>
>
> Mel

Hi

I have flown a lot with both system, probe and electronic on a LX 5000 and now LX7000. It is equally good on both system but the LX 7000 is the only vario I have so no interference from other source.

S6

[son_of_flubber]

Read this for basic knowledge. http://www.clearnav.net/Technical/Variometer%20pneumatics.pdf

If you plumb all three lines, then you can try both approaches and see which works better FOR YOU ON YOUR GLIDER. Your results will depend on the location and accuracy of your static ports and glider type, so anecdotal opinions may not be conclusive.

I have a V7 and I love it. A more interesting question to me is 'what do I display?" I set the analog pointer to display average. That forces me to listen to the beep and keep my eyes off the panel. I keep the backup vario turned off. The average lift indication is a very good indicator of when to stay and when to leave a thermal. It objectively confirms my bad old habits of taking too long to center and staying in a thermal for too long.

What is the real value of displaying short term lift on an audible variometer? For me it would only be a reinforcement of bad old habits developed with non-audible variometers.

I'd like to see the Soaring Safety Foundation take a hammer to all of the old non-audible variometers. That would be a great cost-effective boon to soaring safety (and boost the price of used B40s).

I expect that my V7 will pay for itself by reducing my re-light tows and my average tow height.

[Dan Marotta]

I'll keep my PZL mechanical vario, thank you. It's plumbed as a netto
and gives me good information to compare to my 302 to decide whether to
stop or continue. No hammers allowed near my glider...

Dan Marotta

On 6/9/2014 12:00 PM, son_of_flubber wrote:
> Read this for basic knowledge. http://www.clearnav.net/Technical/Variometer%20pneumatics.pdf
>
> If you plumb all three lines, then you can try both approaches and see which works better FOR YOU ON YOUR GLIDER. Your results will depend on the location and accuracy of your static ports and glider type, so anecdotal opinions may not be conclusive.
>
> I have a V7 and I love it. A more interesting question to me is 'what do I display?" I set the analog pointer to display average. That forces me to listen to the beep and keep my eyes off the panel. I keep the backup vario turned off. The average lift indication is a very good indicator of when to stay and when to leave a thermal. It objectively confirms my bad old habits of taking too long to center and staying in a thermal for too long.
>
> What is the real value of displaying short term lift on an audible variometer? For me it would only be a reinforcement of bad old habits developed with non-audible variometers.
>
> I'd like to see the Soaring Safety Foundation take a hammer to all of the old non-audible variometers. That would be a great cost-effective boon to soaring safety (and boost the price of used B40s).
>
> I expect that my V7 will pay for itself by reducing my re-light tows and my average tow height.
>

[kirk.stant]

Having had both near midairs due to too much time looking at non-audio mechanical varios, and TE probe failures, I now have one of each. My SN10 uses a nice Ilec TE probe (pointed up, by the way ;^), and my backup is a Westerboer 1020 with electronic TE.

And yes, I have two separate redundant battery systems, which has never failed in over 14 years in the same glider...keep it simple and check often.

I also have a big hammer in my trailer (for tiedown stakes) ready to be used on any loose mechanical, non-audio varios...

Kirk
66

[son_of_flubber]

On Tuesday, June 10, 2014 8:15:23 AM UTC-4, kirk.stant wrote:
> My SN10 uses a nice Ilec TE probe (pointed up, by the way ;^), and my backup is a Westerboer 1020 with electronic TE.

Interesting. I think I will set my V7 to computed (electronic) TE and B40 on the TE probe, set both on average and compare the results. You can set a jumper on the B40 to get continuous average on the pointer.

[[email protected]]

My glider doesn't have a TE source so my mechanical vario is uncompensated and the VP-4E uses electronic compensation. I've found that at least in my particular case (ASW-15b + VP-4E) the electronic compensation works very well. As good or better than any pneumatic TE setup I've flown with. By this weekend I should know if the LX8080/V5 combo works well or not with electronic TE as that's what's replacing the old Peschges.

Another pilot in my club got good results using electronic TE on the Cambridge in his DG300. The LX5005 in the club DG-505 uses electronic TE and works fine too. The TE probe on these gliders is only connected to the mechanical vario.

[[email protected]]

I fly an LS8-18 with a 302 and Sage.
The 302 is 100% electronic compensation.
The Sage is on the TE tube.
They read essentially the same. The Sage is just more twitchy.
I will be replacing the 302 with an S80 and it will be 100% electronic.