A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Soaring
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

PowerFlarm and transponders while towing?



 
 
Thread Tools Display Modes
  #1  
Old February 21st 12, 04:57 PM posted to rec.aviation.soaring
bumper[_4_]
external usenet poster
 
Posts: 434
Default PowerFlarm and transponders while towing?

While aero-towing a Mode-C transponder equipped glider, and using
PowerFlarm and transponder in the tow plane, most of the time the
glider will show up on the PF as a threat aircraft. Since the PF
prioritizes threats, this precludes another more distant "intruder"
aircraft as being displayed as a threat. I'm not entirely sure how PF
really deals with this, but it did prompt the idea of turning the
glider's transponder to standby during the tow. And how best to
accomplish this while minimizing the risk of the glider pilot
forgetting to switch the transponder back to ALT after release?

It’s accepted practice to turn off all but one transponder when
formation flying with power aircraft. This to prevent each transponder
from replying to ATC or TCAS at the same time and each stepping on the
other so the receive end gets interference. This probably has not been
much of a problem with a tow plane and glider because traditionally
few tow planes have had transponders.

At Minden, NV, near a busy terminal area and near approach paths into
Reno, all of the tow planes have transponders, and most of the gliders
do as well. Yet we have not adopted a policy of leaving the glider
transponder in standby mode until tow release so as to prevent the
multiple transponder proximity conflict.

Perhaps a change in our normal tug to glider “radio check” prior to
launch: Tug says “transponder on standby” to glider prior to launch,
glider responds, “on standby”. At tow release, glider uses the term,
“transponder on” instead of the “off tow” or “thanks for the tow” used
currently. If glider does not use that phraseology, tow plane
responds, “check transponder on”.

Comments and suggestions . . .

bumper
zz
Minden, NV
  #2  
Old February 21st 12, 06:38 PM posted to rec.aviation.soaring
bumper[_4_]
external usenet poster
 
Posts: 434
Default PowerFlarm and transponders while towing?

On Feb 21, 9:14*am, Tim Newport-Peace ] wrote:


Not sure about PowerFlarm, but on EU Flarm the is an option to suppress
visual and audible warnings, but still Tx data.

Are you operating in 'Nearest' or 'Collision' mode?

Perhaps the answer is RTFM



No, PowerFlarm doesn't have a "collision" mode that is manually
switched. It does use logic to suppress non-collision likely gliders
that are sharing a thermal, but this is an automatic function. Also,
we are not yet dealing with PowerFlarm vs. PowerFlarm, and I've only
done ground tests with two portable units on a collision course in
golf carts :c) as in the US we are just starting to equip and there
are very few airborne PF's, except at contests.

My use of PF so far, is using only the PCAS functions (where the PF
displays only range and altitude of a Mode-C equipped threat
aircraft).

BTW, I did RTFM . . . several times, honest.

bumper

  #3  
Old February 21st 12, 08:47 PM posted to rec.aviation.soaring
Mark Zivley[_2_]
external usenet poster
 
Posts: 1
Default PowerFlarm and transponders while towing?

If the PowerFlarm had an option to surpress 1202 transponder codes in
the US that might help. You eliminate the false alarms from gliders
with the hope that those same gliders adopt powerflarm. Knowing the
adoption rate of PowerFlarm at your gliderport of those gliders with
transponders would allow an informed/calculated decision which would
eliminate false alarms and therefore preserve the value of the PCAS
warnings.


On Feb 21, 11:38*am, bumper wrote:
On Feb 21, 9:14*am, Tim Newport-Peace ] wrote:



Not sure about PowerFlarm, but on EU Flarm the is an option to suppress
visual and audible warnings, but still Tx data.


Are you operating in 'Nearest' or 'Collision' mode?


Perhaps the answer is RTFM


No, PowerFlarm doesn't have a "collision" mode that is manually
switched. It does use logic to suppress non-collision likely gliders
that are sharing a thermal, but this is an automatic function. Also,
we are not yet dealing with PowerFlarm vs. PowerFlarm, and I've only
done ground tests with two portable units on a collision course in
golf carts :c) as in the US we are just starting to equip and there
are very few airborne PF's, except at contests.

My use of PF so far, is using only the PCAS functions (where the PF
displays only range and altitude of a Mode-C equipped threat
aircraft).

BTW, I did RTFM . . . several times, honest.

bumper


  #4  
Old February 21st 12, 11:25 PM posted to rec.aviation.soaring
Chris Nicholas[_2_]
external usenet poster
 
Posts: 197
Default PowerFlarm and transponders while towing?

I suggest a second sticker on the vario.

My first sticker says “gear”. I stick it on the vario when launching.
If it still there when I come off tow and start thermalling etc., it
impedes my view of the vario and reminds me to raise the
undercarriage. When I have done the latter, I move the sticker to the
airbrake/spoiler handle. If it is still there when I approach for
landing, I have forgotten to lower the gear. When I do lower the gear,
I move the sticker back to the vario as I don’t need it for approach
and landing.

For the USA transponder/PowerFlarm, I would have a second sticker on
the vario saying transponder/PowerFlarm. If still there when looking
for lift, it would mean I forgot to switch them on after pulling off
tow.

Cheap, fairly foolproof, and the only time it let me down (or rather I
goofed) was when I forgot to put the sticker on the vario in the first
place, and ended up landing without lowering the gear.

Chris N.
  #5  
Old February 22nd 12, 01:19 AM posted to rec.aviation.soaring
Dan Marotta
external usenet poster
 
Posts: 4,601
Default PowerFlarm and transponders while towing?

But, but, but... A glider on tow is not on a collision course with the tug.
So why is PowerFlar alerting on the glider trailing behind? Why wouldn't it
alwo alert on a glider behind you in a thermal?

I'm still not convinced...


"Chris Nicholas" wrote in message
...
I suggest a second sticker on the vario.

My first sticker says “gear”. I stick it on the vario when launching.
If it still there when I come off tow and start thermalling etc., it
impedes my view of the vario and reminds me to raise the
undercarriage. When I have done the latter, I move the sticker to the
airbrake/spoiler handle. If it is still there when I approach for
landing, I have forgotten to lower the gear. When I do lower the gear,
I move the sticker back to the vario as I don’t need it for approach
and landing.

For the USA transponder/PowerFlarm, I would have a second sticker on
the vario saying transponder/PowerFlarm. If still there when looking
for lift, it would mean I forgot to switch them on after pulling off
tow.

Cheap, fairly foolproof, and the only time it let me down (or rather I
goofed) was when I forgot to put the sticker on the vario in the first
place, and ended up landing without lowering the gear.

Chris N.

  #6  
Old February 22nd 12, 02:14 AM posted to rec.aviation.soaring
Ramy
external usenet poster
 
Posts: 746
Default PowerFlarm and transponders while towing?

On Feb 21, 4:19*pm, "Dan Marotta" wrote:
But, but, but... *A glider on tow is not on a collision course with the tug.
So why is PowerFlar alerting on the glider trailing behind? *Why wouldn't it
alwo alert on a glider behind you in a thermal?

I'm still not convinced...

"Chris Nicholas" wrote in message

...
I suggest a second sticker on the vario.

My first sticker says “gear”. I stick it on the vario when launching.
If it still there when I come off tow and start thermalling etc., it
impedes my view of the vario and reminds me to raise the
undercarriage. When I have done the latter, I move the sticker to the
airbrake/spoiler handle. If it is still there when I approach for
landing, I have forgotten to lower the gear. When I do lower the gear,
I move the sticker back to the vario as I don’t need it for approach
and landing.

For the USA transponder/PowerFlarm, I would have a second sticker on
the vario saying transponder/PowerFlarm. If still there when looking
for lift, it would mean I forgot to switch them on after pulling off
tow.

Cheap, fairly foolproof, and the only time it let me down (or rather I
goofed) was when I forgot to put the sticker on the vario in the first
place, and ended up landing without lowering the gear.

Chris N.


To clarify, Bumper is only talking about the mode C alert, NOT flarm
alert. Mode C only alerts you of the nearest transponder equipped
aircraft (the glider in this case), not of a collision alert. Would
have been great if it was capable of displaying more than one threat,
than there wouldn't be an issue.

Ramy
  #7  
Old February 22nd 12, 03:12 AM posted to rec.aviation.soaring
Chris Nicholas[_2_]
external usenet poster
 
Posts: 197
Default PowerFlarm and transponders while towing?

As Ramy says. Also, if both have PowerFlarm and Transponder, the
glider PF will only show the tug transponder as the nearest and will
not alert to a possible approaching transponder.

As the combination is one entity in air law (I assume it is in the USA
as it is in the UK) it is logical to leave all unambiguous alerts to
the tug pilot. Once separated, the glider needs its own alerts, and
the tug will soon be away.

(Because I have separate PCAS and Flarm in my glider, and no
transponder, I don’t have the problem.)

Not that you can’t still have collisions – I know of at least one UK
fatal collision between a tug and the glider it had not long since
towed up. Be careful out there.

Chris N.
  #8  
Old February 22nd 12, 03:51 AM posted to rec.aviation.soaring
bumper[_4_]
external usenet poster
 
Posts: 434
Default PowerFlarm and transponders while towing?

A possible solution would be to have the PF ignore a constant close-
in, almost same altitude threat (i.e.the glider) after a reasonable
period of time, say a couple of minutes. After staging, this would
have the tow plane PF start to ignore the glider's Mode-C either on
the take off roll or early in the climb. Additionally a software fix
might be tied in to the aircraft type and function only if the "tow
plane" option is menu selected.

I've contacted PowerFlarmUS re. this and some other suggestions and
they are responsive. I wasn't meaning to do an end run, but rather
wanted input from others to confirm if what I'm experiencing is indeed
a problem needing addressing. The seperate issue of tug and glider
transponders interfering with one another while on tow has no fix, I'm
aware of, other than leaving one transponder in standby for the
duration of the tow.

bumper
  #9  
Old February 23rd 12, 07:40 PM posted to rec.aviation.soaring
bumper[_4_]
external usenet poster
 
Posts: 434
Default PowerFlarm and transponders while towing?

At SoaringNV's staff meeting yesterday, we discussed the PowerFlarm
and transponder issue. It was quickly decided that having the glider
transponder on STBY until release would not be workable due to the
fact we often have non-pilots sitting behind the main instrument
panel.

So, yesterday we tried having the tow plane squawk standby until tow
release, then switch to ALT. This works fine in terms of not having
the transponders interfere with each other . . . but does nothing to
resolve the PF beng in constant alarm due to the collision it thinks
might occur at any time between tug and glider.

But, this thread brought elicited a private response reminding me what
I already knew, and that is that the FARs require a transponder be on
at all times if its installed, except as directed by ATC etc. ATC will
almost always direct that all but the "lead" aircraft squawk standby
when formation flying, something that we do often while towing.

To try and resolve this I called Reno Approach who quickly shuffled me
off to NorCal Approach. Talked with a front line manager there who
advised us to do exactly what I suggested. i.e. Leave the tug
transponder squawking STBY until tow release and then don't forget to
switch to ALT. Now he did say that even if we left both on ALT, they
would probably still be able to see us*. But then added that the data
displayed would be confused and would potentially cause conflict
alarms as well.

*A secondary concern is that TCAS equipped aircraft will get good data
from our transponder/s.

bumper
zz
Minden
  #10  
Old February 24th 12, 12:47 AM posted to rec.aviation.soaring
Dan Marotta
external usenet poster
 
Posts: 4,601
Default PowerFlarm and transponders while towing?

Not to sound like a smartass, but have you considered leaving the PowerFlarm
off until release? Is the collision potential so great over your usual tow
route/altitude that you don't feel safe without it?


"bumper" wrote in message
...
At SoaringNV's staff meeting yesterday, we discussed the PowerFlarm
and transponder issue. It was quickly decided that having the glider
transponder on STBY until release would not be workable due to the
fact we often have non-pilots sitting behind the main instrument
panel.

So, yesterday we tried having the tow plane squawk standby until tow
release, then switch to ALT. This works fine in terms of not having
the transponders interfere with each other . . . but does nothing to
resolve the PF beng in constant alarm due to the collision it thinks
might occur at any time between tug and glider.

But, this thread brought elicited a private response reminding me what
I already knew, and that is that the FARs require a transponder be on
at all times if its installed, except as directed by ATC etc. ATC will
almost always direct that all but the "lead" aircraft squawk standby
when formation flying, something that we do often while towing.

To try and resolve this I called Reno Approach who quickly shuffled me
off to NorCal Approach. Talked with a front line manager there who
advised us to do exactly what I suggested. i.e. Leave the tug
transponder squawking STBY until tow release and then don't forget to
switch to ALT. Now he did say that even if we left both on ALT, they
would probably still be able to see us*. But then added that the data
displayed would be confused and would potentially cause conflict
alarms as well.

*A secondary concern is that TCAS equipped aircraft will get good data
from our transponder/s.

bumper
zz
Minden


 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
PowerFLARM Paul Remde Soaring 9 November 6th 10 05:30 AM
PowerFlarm response to transponders Mark Soaring 1 November 1st 10 04:07 PM
transponders in EU Sandro Soaring 2 February 2nd 07 02:02 PM
Transponders [email protected] Home Built 2 March 2nd 05 03:39 AM
Transponders Mil80C Soaring 64 February 12th 04 06:46 PM


All times are GMT +1. The time now is 04:39 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AviationBanter.
The comments are property of their posters.