Ideal Variometer

I have a few suggestions for the way my vario, an LX1600 should work,
ideally.

I would like it to switch between "STF mode" and "Climbing mode" when
I hit lift or sink. Ideally it should switch to climbing mode when I
hit lift that equals or exceeds my MC setting. Of course there would
still be a manual override switch when you are low and/or scratching.

Do other vario manufactures set up their varios to work the way I
describe? If so, which ones?

Currently it switches between modes using three methods all of which I
think are inferior. It will switch to Climbing mode when I start
turning, when the speed drops below a set value, or when I manually
switch modes.

How do other manufactures do it?

Thanks, Ryan

On Aug 20, 9:21*am, ryanglover1969 wrote:
I have a few suggestions for the way my vario, an LX1600 should work,
ideally.

I would like it to switch between "STF mode" and "Climbing mode" when
I hit lift or sink. Ideally it should switch to climbing mode when I
hit lift that equals or exceeds my MC setting. Of course there would
still be a manual override switch when you are low and/or scratching.

Do other vario manufactures set up their varios to work the way I
describe? If so, which ones?

Currently it switches between modes using three methods all of which I
think are inferior. It will switch to Climbing mode when I start
turning, when the speed drops below a set value, or when I manually
switch modes.

How do other manufactures do it?

Thanks, Ryan

I think you'll find a lot of personal preferences in how to switch
modes with a STF vario.

I use a magnetic reed switch on the flap controls so the vario
switches to climb when I select a climb flap setting which has worked
fine for me since I tend to forget to switch the vario manually.

Some people have added an override toggle switch for cruise climb
situations but I think there is a case to be made for automatic
switching.

On Aug 20, 11:21*am, ryanglover1969
wrote:
I have a few suggestions for the way my vario, an LX1600 should work,
ideally.

I would like it to switch between "STF mode" and "Climbing mode" when
I hit lift or sink. Ideally it should switch to climbing mode when I
hit lift that equals or exceeds my MC setting. Of course there would
still be a manual override switch when you are low and/or scratching.

Do other vario manufactures set up their varios to work the way I
describe? If so, which ones?

Currently it switches between modes using three methods all of which I
think are inferior. It will switch to Climbing mode when I start
turning, when the speed drops below a set value, or when I manually
switch modes.

How do other manufactures do it?

Thanks, Ryan

Borgelt B-500 either switches on manual switch, or can be set to
switch automatically when netto lift exceeds MC.

Dan

On Thu, 20 Aug 2009 08:21:42 -0700, ryanglover1969 wrote:

I have a few suggestions for the way my vario, an LX1600 should work,
ideally.

I would like it to switch between "STF mode" and "Climbing mode" when I
hit lift or sink. Ideally it should switch to climbing mode when I hit
lift that equals or exceeds my MC setting. Of course there would still
be a manual override switch when you are low and/or scratching.

Do other vario manufactures set up their varios to work the way I
describe? If so, which ones?

Currently it switches between modes using three methods all of which I
think are inferior. It will switch to Climbing mode when I start
turning, when the speed drops below a set value, or when I manually
switch modes.

How do other manufactures do it?

I have an SDI C4 that offers three modes:

- a manual switch - I've not fitted it so can't comment on how well
it works for me.

- by GPS. I tried this and didn't like it. The idea is that the C4
switches to climb mode after a 90 or 270 degree turn and back
to cruise when you straighten out. One thing that I didn't like
is that it stays in cruise mode when running a cloud street.
This means that it makes faster/slower noises rather than climb rate
noises even when the lift is weak and you're flying slowly. Also,
I like the vario to be in climb mode when I start to turn.

- on IAS. There are separate speed settings for climb-cruise and
cruise- climb. Typically the first of these is the faster setting.
It takes a bit of trial and error to get the switching speeds
set for your glider and flying style, but when its set correctly the
vario is automatically in the appropriate mode more than 90% of the
time.

IME speed switching is by far the best choice. The only improvement
I can suggest is that an override switch would be nice if it had three
positions:

climb
auto (use speed switching)
cruise

The older C3 had this facility but it was omitted from the C4 for some
reason.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Ryan,

Most varios I know use one of the techniques you mention for
switching.

I think you'll find a lot of experienced pilots essentially ignore
cruise mode by putting a wide dead band on the audio. The view is that
chasing the speed director creates drag more than it optimizes cruise
speed. I generally change cruise speed only for extreme sink. Also I
tend to try to climb straight ahead, even if the lift is a bit below
my McCready setting (again, most experienced pilots I know fly slower
than the speed indicated by McCready theory for a host of reasons).

Given all that I'd set my vario to switch to climb based on airspeed,
and a pretty high one at that. My concern with your suggestion is that
you might get a lot of spurious switching to climb with gusts or
thermals you don't intend to climb in unless you put a time lag on it
- which would create other problems.

9B

On Aug 21, 7:32*am, Martin Gregorie
wrote:
On Thu, 20 Aug 2009 08:21:42 -0700, ryanglover1969 wrote:
I have a few suggestions for the way my vario, an LX1600 should work,
ideally.

I would like it to switch between "STF mode" and "Climbing mode" when I
hit lift or sink. Ideally it should switch to climbing mode when I hit
lift that equals or exceeds my MC setting. Of course there would still
be a manual override switch when you are low and/or scratching.

Do other vario manufactures set up their varios to work the way I
describe? If so, which ones?

Currently it switches between modes using three methods all of which I
think are inferior. It will switch to Climbing mode when I start
turning, when the speed drops below a set value, or when I manually
switch modes.

How do other manufactures do it?

I have an SDI C4 that offers three modes:

- a manual switch - I've not fitted it so can't comment on how well
* it works for me.

- by GPS. I tried this and didn't like it. The idea is that the C4
* switches to climb mode after a 90 or 270 degree turn and back
* to cruise when you straighten out. One thing that I didn't like
* is that it stays in cruise mode when running a cloud street.
* This means that it makes faster/slower noises rather than climb rate
* noises even when the lift is weak and you're flying slowly. Also,
* I like the vario to be in climb mode when I start to turn.

- on IAS. There are separate speed settings for climb-cruise and
* cruise- climb. Typically the first of these is the faster setting.
* It takes a bit of trial and error to get the switching speeds
* set for your glider and flying style, but when its set correctly the
* vario is automatically in the appropriate mode more than 90% of the
* time.

IME speed switching is by far the best choice. The only improvement
I can suggest is that an override switch would be nice if it had three
positions:

* * * * climb
* * * * auto (use speed switching)
* * * * cruise

The older C3 had this facility but it was omitted from the C4 for some
reason.

--
martin@ * | Martin Gregorie
gregorie. | Essex, UK
org * * * |

I believe the LX160 works like that. It has a 3 position switch with
vario, speed command, and auto mode. In auto mode the switch
is done based on airspeed.

I haven't flown with the LX160 yet (I'll let you know in a month or
two maybe).
I did fly with an LX5000 for a few years, but it didn't have a switch
like that.
I found it so annoying as a matter of fact that I would turn the sound
all the
way down and just use the B40 audio at all times.

For that matter, I generally don't switch speed that much. When I'm
cruising
between thermals, I'll just set my airspeed to whatever the PDA tells
me is a
good speed to fly, and I'll only slow up when I get to the next
cloud. I'll drop
to min sink speed and fly some S-turns to pick up energy, and then
speed up
back to the interthermal speed unless I'm low or have hit a corker. I
don't
change the trim while I'm doing that either. Final glide is another
issue.
When doing that my PDA shows a table of airspeeds and glideslopes,
so I adjust my airspeed to whatever the fastest speed to get me home
is.
Then again, maybe that's just the style I developed based on what I
had
to work with. Perhaps I'll change once I only have the LX160 for
audio.

-- Matt

Martin Gregorie wrote:
On Thu, 20 Aug 2009 08:21:42 -0700, ryanglover1969 wrote:

I have a few suggestions for the way my vario, an LX1600 should work,
ideally.

I would like it to switch between "STF mode" and "Climbing mode" when I
hit lift or sink. Ideally it should switch to climbing mode when I hit
lift that equals or exceeds my MC setting. Of course there would still
be a manual override switch when you are low and/or scratching.

Do other vario manufactures set up their varios to work the way I
describe? If so, which ones?

Currently it switches between modes using three methods all of which I
think are inferior. It will switch to Climbing mode when I start
turning, when the speed drops below a set value, or when I manually
switch modes.

How do other manufactures do it?

I have an SDI C4 that offers three modes:

- a manual switch - I've not fitted it so can't comment on how well
it works for me.

- by GPS. I tried this and didn't like it. The idea is that the C4
switches to climb mode after a 90 or 270 degree turn and back
to cruise when you straighten out. One thing that I didn't like
is that it stays in cruise mode when running a cloud street.
This means that it makes faster/slower noises rather than climb rate
noises even when the lift is weak and you're flying slowly.

I always assumed cruise mode was the appropriate mode while running a
cloud street. Isn't that "cruising"? What tactic are you using, if not
the usual McCready speeds?

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* "Transponders in Sailplanes" http://tinyurl.com/y739x4
* Sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

On Aug 21, 7:44*am, Eric Greenwell wrote:
I always assumed cruise mode was the appropriate mode while running a
cloud street. Isn't that "cruising"? What tactic are you using, if not
the usual McCready speeds?

--
Eric Greenwell - Washington State, USA

I don't know that many pilots who fly the speed director anymore.
Under a cloud street when climbing straight ahead most slow down and
use the vario mode audio to find the best place to stop and thermal
when they need it as well as to pick the best line.

In terms of the pure theory it isn't totally clear to me that the same
theory applies to climbing straight ahead as applies to circling
climbs and glides. The classical theory also breaks down a bit when
you start considering the effectiveness of search patterns versus
speed under a street and the losses associated with dolphining
flight.

For me on a good day in the west if the lift is less than 2-3 kts I
keep cruising, if it's more than that I'll pull back to around best
glide and climb straight ahead. If I think it's going to turn into
something stronger or conditions further ahead look less promising
I'll pull back a bit more and perhaps start hunting around a bit. On
the run I have three speeds - in trouble, on the run and booming -
70-75 knots, 80-85 knots and 90-95 knots respectively (dry). If I get
a lot of sink I bump up one speed level more or less. No trying to
chase the speed director needle. I figure mental energy is better
spent on the bigger strategic considerations - like which way to go.

My 2c - I'm sure everyone has their own take on it.

9B

On Aug 21, 7:44*am, Eric Greenwell wrote:
Martin Gregorie wrote:
On Thu, 20 Aug 2009 08:21:42 -0700, ryanglover1969 wrote:

I have a few suggestions for the way my vario, an LX1600 should work,
ideally.

I would like it to switch between "STF mode" and "Climbing mode" when I
hit lift or sink. Ideally it should switch to climbing mode when I hit
lift that equals or exceeds my MC setting. Of course there would still
be a manual override switch when you are low and/or scratching.

Do other vario manufactures set up their varios to work the way I
describe? If so, which ones?

Currently it switches between modes using three methods all of which I
think are inferior. It will switch to Climbing mode when I start
turning, when the speed drops below a set value, or when I manually
switch modes.

How do other manufactures do it?

I have an SDI C4 that offers three modes:

- a manual switch - I've not fitted it so can't comment on how well
* it works for me.

- by GPS. I tried this and didn't like it. The idea is that the C4
* switches to climb mode after a 90 or 270 degree turn and back
* to cruise when you straighten out. One thing that I didn't like
* is that it stays in cruise mode when running a cloud street.
* This means that it makes faster/slower noises rather than climb rate
* noises even when the lift is weak and you're flying slowly.

I always assumed cruise mode was the appropriate mode while running a
cloud street. Isn't that "cruising"? What tactic are you using, if not
the usual McCready speeds?

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* "Transponders in Sailplanes"http://tinyurl.com/y739x4
* * * Sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" atwww.motorglider.org

I use the usual tactics with regards to MC speeds. But my question has
more to do with how other varios switch between Climbing and Cruising
mode. I would rather my LX1600 switched to Climbing mode when I
encounter lift equal or greater than my MC setting instead the way it
currently operates.

With regards to the MC setting I generally set my MC less than the
average climb rate I'm experiencing. If I'm getting 4 knots average
and if conditions look similar up ahead I'll set my MC around 3 knots.
I use a deadband of 1.5 to 2 knots before I get an audio signal to
speed up or slow down. On a typical day here in Oklahoma with good
clouds I tend to thermal in lift that is equal or better than the
average for the day and slow down and do some S turns in the weaker
stuff.

Thanks for the input from everybody.

Ryan Glover

On Aug 21, 2:38*pm, ryanglover1969 wrote:

I use a deadband of 1.5 to 2 knots before I get an audio signal to
speed up or slow down.

!!!!

Okay, this isn't responsive to your question, but...

How about a dead band closer to 20 kts? There just isn't any reason
to strive for "perfection" here, because:

1. The achieved XC speed vs % of "ideal" Mc speed to fly has a very
flat optimum. +/- 10 kts has very little effect on achieved speed.

2. Your attention is better placed on other things, e.g. the sky (or
traffic, possibly). Choosing the best route and choosing the best
thermals has a HUGE effect on XC speed.

3. The danged vario is telling you about the last time constant of
lift or sink, not what happens next.

4. As noted earlier, zoomies are inefficient, possibly very
inefficient depending on what you are flying.

5. Chasing needles isn't fun and in extreme cases it can be
hazardous. We knew a guy -- now retired from soaring I think -- who
was really into his speed to fly vario. My God, the zoomies he'd do
in the clear blue sky... we gave him a lot of room.

Watch how KS flies in "Fine Week of Soaring". That's a better model.

regards,

Evan Ludeman / T8