Trig TT21 Transponder ... reports?

On Fri, 20 Aug 2010 07:14:01 -0700, Andy wrote:

draws 0.8 amps @ 12v

I've not been near an airfield for 10 years now, but are there no
advances in solar power/battery technology since then that improve a
glider's power supply? What is a typical glider's current requirement?

--
Alex

On Aug 20, 11:33*am, Alex Potter wrote:
On Fri, 20 Aug 2010 07:14:01 -0700, Andy wrote:
draws 0.8 amps @ 12v

I've not been near an airfield for 10 years now, but are there no
advances in solar power/battery technology since then that improve a
glider's power supply? What is a typical glider's current requirement?

--
Alex

I run my whole panel on less than 0.8 amp average. PDA, logger,
vario, radio. I use a 14 AH battery, useful capacity about 10 AH,
adding 0.8 amp would take me down to about 6 hours duration. I'd have
to add another battery somewhere to get my target 10 hour capacity.
Solar would be an option... but dang those things are ugly on a pretty
glider.

0.8 amps isn't a deal breaker for me... but less is better.

The Navworx product isn't generating any interest here because there
is at present no way to build a complete system out of the thing that
will work in a glider flown in proximity to other gliders. Possibly
someone like Flarm could do this... but the price point is going to be
difficult, $2500 transceiver, plus whatever additional for a display
and software... I don't see that catching on.

-Evan Ludeman / T8

It's a no-brainer. Everyone who flies gliders with other gliders
needs to get a PowerFlarm. Everyone who shares airspace with
airliners needs to get a transponder. It's just that simple.

The SSA rules committee needs to immediately adopt a mandate for
PowerFlarm in 2011 sanctioned contests so that the Flarm folks
understand their mission and can get production ramped accordingly.
Let's not have any more mid-airs -- they are ruining the fun.

A big thank you to Darryl for his extrodinarily clear explainations of
a complex subject.

On Aug 20, 11:09*am, Steve Koerner wrote:
It's a no-brainer. *Everyone who flies gliders with other gliders
needs to get a PowerFlarm. *

I, for one, don't think it is that simple.

I agree that FLARM is the best available technology for glider on
glider collision avoidance. That part is the no brainer.

The situation as I understand it is that one manufacturer of devices
that uses FLARM technology has expressed an intention to launch a
product (PowerFLARM) in USA. If this produduct is FLARM compatible it
must mean that the company holding the rights to the FLARM technology
has authorized the use of it in USA. That is something that they
have, in the past, prohibited.

PowerFLARM includes features that are not included by other
manufacturers of equipment using FLARM technology. There is no
indication in the specifications, or elsewhere on their website, how
these additional features will be integrated with the well proven
FLARM functionality.

If the holder of the rights to the FLARM technology has authorized its
use in USA what is to stop other companies launching a FLARM product
to the US market. Perhaps such a product would not have the
additional features of the Power FLARM unit but would support only the
basic FLARM functionality that has a proven track record. Perhaps that
device, or family of devices, would be far less expensive than
PowerFLARM. Perhaps these devices already exist and just need a
firmware change to assign the correct frequencies for use in USA.

The SSA rules committee needs to immediately adopt a mandate for
PowerFlarm in 2011 sanctioned contests

No rule should require the use of a particular manufacturer's
product. The rule that should be considered is one that requires the
use of a FLARM compatible device.

so that the Flarm folks
understand their mission and can get production ramped accordingly.

Who are the FLARM folks that you refer to? In an earlier post you
said "Andy -- have some faith. The Flarm designers are glider pilots
and have been at this for years. The track record is that of
remarkable
success". Do you mean the manufacturer of PowerFLARM, or perhaps the
holder of the FLARM rights. To the best of my knowledge these are not
the same company. (Maybe someone that knows the relationship between
the various companies and the people involved could comment)


Andy

On Aug 20, 12:15*pm, Andy wrote:
On Aug 20, 11:09*am, Steve Koerner wrote:

It's a no-brainer. *Everyone who flies gliders with other gliders
needs to get a PowerFlarm. *

I, for one, don't think it is that simple.

I agree that FLARM is the best available technology for glider on
glider collision avoidance. *That part is the no brainer.

The situation as I understand it is that one manufacturer of devices
that uses FLARM technology has expressed an intention to launch a
product (PowerFLARM) in USA. *If this produduct is FLARM compatible it
must mean that the company holding the rights to the FLARM technology
has authorized the use of it in USA. *That is something that they
have, in the past, prohibited.

PowerFLARM includes features that are not included by other
manufacturers of equipment using FLARM technology. *There is no
indication in the specifications, or elsewhere on their website, how
these additional features will be integrated with the well proven
FLARM functionality.

If the holder of the rights to the FLARM technology has authorized its
use in USA what is to stop other companies launching a FLARM product
to the US market. *Perhaps such a product would not have the
additional features of the Power FLARM unit but would support only the
basic FLARM functionality that has a proven track record. Perhaps that
device, or family of devices, would be far less expensive than
PowerFLARM. *Perhaps these devices already exist and just need a
firmware change to assign the correct frequencies for use in USA.

The SSA rules committee needs to immediately adopt a mandate for
PowerFlarm in 2011 sanctioned contests

No rule should require the use of a particular manufacturer's
product. *The rule that should be considered is one that requires the
use of a FLARM compatible device.

so that the Flarm folks
understand their mission and can get production ramped accordingly.

Who are the FLARM folks that you refer to? *In an earlier post you
said "Andy -- have some faith. * The Flarm designers are glider pilots
and have been at this for years. *The track record is that of
remarkable
success". *Do you mean the manufacturer of PowerFLARM, or perhaps the
holder of the FLARM rights. *To the best of my knowledge these are not
the same company. *(Maybe someone that knows the relationship between
the various companies and the people involved could comment)

Andy

Flarm and Butterfly (the actual manufacturer of PowerFLARM) are
cooperating very closely to bring this first Flarm based product to
the USA market. As with all other Flarm products the core technology
is developed by Flarm. Urs Rothacher the guy posting on r.a.s in these
threads is the CEO and one of the founders of of Flarm and is very
technical. He is clearly buried working to get the PowerFLARM out.

No existing Flarm devices are FCC approved in the USA and therefore
none of them can be legally sold. Unfortunately there is confusing
information put up on some web sites (yes you Paul Remde :-)) implying
some Flarm devices are available in the USA, there just are no FCC
approvals AFAIK. Some of us have had conversations with Urs about this
and one of the things that Flarm is working on in this whole project
is really clean FCC approval of the new generation hardware inside the
PowerFLARM product. That takes time, effort and $$$.

I also see no reason to specify a "powerFLARM" device for USA contest
rules. Specifying "Flarm" based product or similar likely achieves
what may be desired. And I tend to believe that is what USA rules
folks might do in any language that allowed/required etc. this
technology.

Darryl

Andy:

I agree. It should be a "Flarm compatible device" that is mandated
for 2011 contests not PowerFlarm per se.

I don't understand the nit picking about rights holders vs
manufacturers.

On Aug 20, 12:44*pm, Steve Koerner wrote:

I don't understand the nit picking about rights holders vs
manufacturers.

It's a question of what flexibility a manufacturer has to modify the
core technology/firmware to make it compatible with new features that
are not supported by other FLARM products. The new features need to be
integrated not just stuffed in the same box.

If, as Darrly says, the holder of the rights and the manufacturer are
working together on PowerFLARM then I agree it should be a non
issue.


Andy

On Aug 20, 8:33*am, Alex Potter wrote:
On Fri, 20 Aug 2010 07:14:01 -0700, Andy wrote:
draws 0.8 amps @ 12v

I've not been near an airfield for 10 years now, but are there no
advances in solar power/battery technology since then that improve a
glider's power supply? What is a typical glider's current requirement?

--
Alex

On Aug 20, 8:33 am, Alex Potter wrote:
On Fri, 20 Aug 2010 07:14:01 -0700, Andy wrote:
draws 0.8 amps @ 12v

I've not been near an airfield for 10 years now, but are there no
advances in solar power/battery technology since then that improve a
glider's power supply? What is a typical glider's current requirement?

--
Alex

With gliders we fly you cannot easily stick solar panels over large
areas of the glider because of cost and critical aerodynamic concerns
and concerns about solar heating the underlying composite structure.
There are specialized solar project exceptions. The manufacturer who
dominates solar panels for gliders today is Strobl (http://www.strobl-
solar.de ) and their panels are available preinsalled from all leading
glider manufacturers or as add-on for a large number of gliders. See
my blog at http://www.darryl-ramm.com/2007/01/s...or-sailplanes/
for what a retrofit kit looks like.

They typically deliver 15-30 watt maximum for several thousand dollars
outlay. The Stobl systems use crystalline wafers in a semi-flexible
ETFE (hey that what is used on Trefzel wire, oops another thread...)
type plastic encapsulation. Likely all hand-built. The panels are
attached with 3M ultra-high-bond double sided tape. Some installations
will have molded in recesses for the panels some use hand applied
filleting, some wedge trim strips around the panels. The crystalline
cells give relatively high efficiency even with only partial fill
factor on the panels. Other options emerging might be to use amorphous
thin film panels but you are typical starting with low efficiency. I
have the larges set of Strobl panels I can get on my ASH-26E engine
bay doors that gives a peak spec of 30W (2.5A @ 12V). The actual
delivered power is *much* lower. And you should rely not plan on solar
panels to significantly boost battery capacity for a single flight as
output drops dramatically under cloud streets, overcast sky etc. I
really like the Strobl panels but it may be more useful/safer to think
of them for use for ground charging of a tied down glider (e.g. some
airports have issues with separate panels near the aircraft when tied
down) and as a way of stretching capacity over several days when usual
ground charging infrastructure is not available.

Although it obviously varies widely a typical power consumption number
for a glider avionics is roughly around 0.8 amp (as Evan noted his is)
for what I am guessing is a typical setup of C302 style computer, a
PDA, and VHF radio. Owners should measure and calculate the loads in
the glider and estimate the battery capacity needed or run time
available from the batteries they have. Do not just divide the nominal
"Ah capacity" by amp load, especially at higher loads, you need to use
the discharge curves data from a manufacturer to estimate the
available run time of a battery at a particular load (most good VRLA
batteries are close enough to use another manufacturers spec sheet for
a similar sized battery).

Transponders (and their encoders) used to be considered a large power
hog. And in the days of horse drawn buggies, steam locomotives and
traveling wave tube amplifiers etc. they were. While they are much
more efficient nowadays, you do need to make sure they fit within a
ships power budget. Modern transponders range in power consumption
from ~0.5A for a Becker 4401 175W and ACK A30 encoder to around ~0.3A
for a Trig TT21 (with built in encoder). Transponder power consumption
will vary depending on interrogation rates and temperature (for the
encoder heater). i.e. The Trig TT21 uses less power than large PDAs
like the iPAQ 4700. The numbers here are realistic for typical glider
operations.

The NavWorx ADS600-B specs implies it consumes 0.8A at 12V. I have no
idea if this is accurate or not, it may be less in practice. Today you
need a separate display with third party software to get traffic
information/warnings from the device, so guess around 0.45A (e.g. for
a iPAQ 4700 PDA dedicated to the UAT data display).

Most gliders have some combination of one or more "7Ah" or "12Ah" VRLA
batteries. So to give a rough idea of maximum run time from typical
single batteries ... (These number are very rough, I don't have my
discharge spreadsheet handy that will do this properly, but they give
the flavor.)

2.0A load = guess of typical glider load + NavWorx ADS-600B + iPAQ
4700 for UAT traffic display
@2.0Ah load a typical "7Ah" VRLA battery ~ 2.7 hours
@2.0Ah load a typical "12Ah" VRLA battery ~ 5.2 hours

---

Since one scenario is people with Mode C might go UAT vs. buy a new
Mode S/1090ES capable transponder. A UAT is does not make a glider
visible on TCAS, so if you fly near airliners or fast jets that
transponder is a good idea. If you do not then just look at the
numbers above)

2.5A load = guess of typical glider load + Becker Mode C + ACK30 +
NavWorx ADS600-B + iPAQ 4700 for UAT traffic display
@2.5Ah load a typical "7Ah" VRLA battery ~ 2.2 hours
@2.5Ah load a typical "12Ah" VRLA battery ~ 4.1 hours

---

All these are numbers are for effectively fully discharging the
battery, you should really not plan on running down batteries this
much on typical flights and having no safety margin. Some fudge (20%)
should be deducted from these numbers for typical battery aging. For
very cold flights (e.g. wave) then maybe halve these run times. And
again do the real calculations for your actual setup.

How much battery capacity do you need? My longest flight was 8-9 hours
(in my old glider with no solar panel). A typical "serious" XC flight
for me is around 5-6 hours.

This all assumes the the NavWorx ADS600-B nominal 0.7A spec at 14VDC
nominal (i.e. 0.8A at 12VDC) is correct. It could be lower in
practice. I'm not even sure why we are down this rat hole. None of
this is not a slight on NavWorx, their UAT transceiver was not
designed for the glider market, NavWorx does not claim it is intended
for the glider market, or target any marketing to the glider market
AFAIK. And issues with incompatibility with all existing (Flarm serial
display protocol based) glider traffic display/software, lack of any
third party traffic display/warning product tuned for glider specific
type environments (esp. gaggles), lack of traffic collision/alert
warning from the receiver box etc. are also issues for use in the
glider market. I am convinced that a company who wanted to target the
USA glider marker with a UAT product would have no deep technical
issues addressing these items, or reducing the power consumption
significantly today. The issue is justifying a business case for a
company to do that for the intersection of the relatively small USA
UAT market and the much smaller USA glider market.

BTW some older slides and spreadsheets on glider batteries at
http://www.darryl-ramm.com/glider-batteries/ but I don't think these
make much sense unless you've seen me present them. I originally made
that presentation because of confusion around batteries and
transponders. That confusion went both ways, people way under capacity
for their loads (BTW interestingly often with PDAs and ClearNav type
devices not just transponders) and people thinking they could never
use a transponder, often based on out of date info on transponder
power requirements.

Darryl

On Fri, 20 Aug 2010 12:11:21 -0700, Darryl Ramm wrote:

[ much snippage of useful and interesting post ]

Thanks for that, Darryl. Still not too much progress then....

--
Alex

On Fri, 20 Aug 2010 12:11:21 -0700, Darryl Ramm wrote:

Although it obviously varies widely a typical power consumption number
for a glider avionics is roughly around 0.8 amp (as Evan noted his is)
for what I am guessing is a typical setup of C302 style computer, a PDA,
and VHF radio. Owners should measure and calculate the loads in the
glider and estimate the battery capacity needed or run time available
from the batteries they have. Do not just divide the nominal "Ah
capacity" by amp load, especially at higher loads, you need to use the
discharge curves data from a manufacturer to estimate the available run
time of a battery at a particular load (most good VRLA batteries are
close enough to use another manufacturers spec sheet for a similar sized
battery).

I'd seriously suggest a visit to your local RC model shop to look at
battery chargers. $60 - $100 gets you a cycling charger that can not only
peak charge a partially discharged SLA battery without harming it, but
can measure its capacity. Record the measured capacity every year and bin
the battery when it shows a 30% drop and you may even save money.

Slinging an SLA battery every three years is common wisdom here, yet last
winter my three year old batteries still had 90% of their nominal
capacity. Bin them? I think not!

FWIW these batteries have always been charged with a peak charger.

PS; sorry for hi-jacking the thread, but it seemed appropriate.

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