FLARM question

[Eric Bick (1DB)]

I'm trying a portable FLARM unit for first day today. Two issues on fitting it into the cockpit arose (I fly a Pegase101A).

1. There is insufficient room between panel top and canopy for both antennas to stand up straight. If I put the unit so the taller antenna is on canopy centerline, then I can get both antennas up at about 15 - 20 degrees off vertical.

Question 1 is whether this off-angle is an issue or not for xmt/rcv. Articles I've read indicate it well might be.

2. I can't see the tow plane out the front over or around the unit. The panel top is pretty close to the canopy (hence the antenna issue), so adding the height of the unit obscures the view out front terribly.

Question #2 & 3: So has anyone else (flying a Pegase) found a way around this with a portable unit so that it is still usable? Or is my panel layout/height in cockpit unique? I don't think flying with the FLARM in my lap is the answer, nor is flying tow in a constant slip.

Eric Bick

[Sierra Whiskey]

I just did a portable PF installation on my LS-3A. This link is a great place to start. Download the PDF and read through it a few times. It was provided by the manufacturer and provides details and reasoning behind the antenna installation requirements.

https://www.google.com/url?sa=t&source=web&rct=j&ei=G7h0U6__M832oASZ7YCYBw&url=https://www.cumulus-soaring.com/flarm/PowerFLARM_Application_Note_ANTENNAS1.pdf&cd=1&ved=0CCQQFjAA&usg=AFQjCNFn_qBoUjcX-p9nWwW6tmqWu8cCmg

You will notice in the document, the standard dipole antenna is considered to have medium performance, and as you saw they can get in the way. I went ahead and bought the remote center fed dipole antennas (be sure to pay attention to the SMA polarity) and have found that my units sensitivity to other FLARM signals is very high, and I was able to place the antennas out of sight and in a spot that has an optimal view in all directions. The only standard dipole antenna on my unit now is the ADS-B/ Transponder antenna, and with nothing else around it I have a lot of flexibility to angle it safely away from the canopy. The key there is that the PF antennas are listening for a relatively weak signal where the ADS-B antenna is looking for a very strong signal.

I hope this helps!

[[email protected]]

On Wednesday, May 14, 2014 8:55:14 PM UTC-7, Eric Bick (1DB) wrote:
> I'm trying a portable FLARM unit for first day today. Two issues on fitting it into the cockpit arose (I fly a Pegase101A).
>
> 1. There is insufficient room between panel top and canopy for both antennas to stand up straight. If I put the unit so the taller antenna is on canopy centerline, then I can get both antennas up at about 15 - 20 degrees off vertical.
>
> Question 1 is whether this off-angle is an issue or not for xmt/rcv. Articles I've read indicate it well might be.
>
> 2. I can't see the tow plane out the front over or around the unit. The panel top is pretty close to the canopy (hence the antenna issue), so adding the height of the unit obscures the view out front terribly.
>
> Question #2 & 3: So has anyone else (flying a Pegase) found a way around this with a portable unit so that it is still usable? Or is my panel layout/height in cockpit unique? I don't think flying with the FLARM in my lap is the answer, nor is flying tow in a constant slip.
>
> Eric Bick

The recommendation is to have the antennae as close to vertical as possible - at least not more than 15 degrees off - or the range can be affected. If I had to pick one to compromise on I'd pick the ADS-B antenna to put off-vertical because ADS-B systems and transponders put out a lot more power so you'll likely pick them up anyway. I'm also assuming you care more about picking up the Flarm traffic, but that may not be the case.

I've seen some Schleicher mounts that put the unit in front of the glare shield so you can have canopy clearance and not have it in front of your instruments. Not sure if this works for a Pegase. I think Rex Mayes at Williams Soaring developed it.

Hope that helps,

Andy
9B

[[email protected]]

When you are circling in a 45 bank, the antennae are far from vertical and seem still to work....

mj

[darrylr]

On Thursday, May 15, 2014 1:52:15 PM UTC-7, wrote:
> When you are circling in a 45 bank, the antennae are far from vertical and seem still to work....
>
>
>
> mj

Yes but the signals is vertically polarized (vertical relative to the antenna) and your job as installer is to get the antennas as vertical as possible so that that average the signal transmission/reception is maximized.

Antenna design 101, they are linear/vertical polarized antennas, get the antennas as vertical as possible.

[Mike the Strike]

On Thursday, May 15, 2014 7:41:25 PM UTC-7, darrylr wrote:
> On Thursday, May 15, 2014 1:52:15 PM UTC-7, wrote:
>
> > When you are circling in a 45 bank, the antennae are far from vertical and seem still to work....
>
> >
>
> >
>
> >
>
> > mj
>
>
>
> Yes but the signals is vertically polarized (vertical relative to the antenna) and your job as installer is to get the antennas as vertical as possible so that that average the signal transmission/reception is maximized.
>
>
>
> Antenna design 101, they are linear/vertical polarized antennas, get the antennas as vertical as possible.

....and don't bank while you are flying!

Mike

[[email protected]]

On Thursday, May 15, 2014 9:04:22 PM UTC-7, Mike the Strike wrote:
> On Thursday, May 15, 2014 7:41:25 PM UTC-7, darrylr wrote:
>
> > On Thursday, May 15, 2014 1:52:15 PM UTC-7, wrote:
>
> >
>
> > > When you are circling in a 45 bank, the antennae are far from vertical and seem still to work....
>


Now that we are starting to get AHRS into the cockpit, you can gimbal the antenna so it's always vertical.

:-)

9B

[Richard[_9_]]

On Friday, May 16, 2014 9:24:15 AM UTC-7, wrote:
> On Thursday, May 15, 2014 9:04:22 PM UTC-7, Mike the Strike wrote:
>
> > On Thursday, May 15, 2014 7:41:25 PM UTC-7, darrylr wrote:
>
> >
>
> > > On Thursday, May 15, 2014 1:52:15 PM UTC-7, wrote:
>
> >
>
> > >
>
> >
>
> > > > When you are circling in a 45 bank, the antennae are far from vertical and seem still to work....
>
> >
>
>
>
>
>
> Now that we are starting to get AHRS into the cockpit, you can gimbal the antenna so it's always vertical.
>
>
>
> :-)
>
>
>
> 9B

I sell an antenna with a hinge and a cat. Throw the cat and watch (a cat always comes down feet first) then adjust the antenna.

Richard
www.craggyaero.com

[bumper[_4_]]

On Friday, May 16, 2014 10:01:11 AM UTC-7, Richard wrote:
> On Friday, May 16, 2014 9:24:15 AM UTC-7, wrote:

> I sell an antenna with a hinge and a cat. Throw the cat and watch (a cat always comes down feet first) then adjust the antenna.
>
>
>
> Richard
>
> www.craggyaero.com

I tried the "hinge and cat kit" and found it to have serious flaws. The hinge was loose so the antenna flops around in turbulence. Not being a helicopter pilot, I found it difficult to stay in a tight thermal while using stick and rudder trying to keep the antenna up straight. The cat didn't help much, the one I received was freeze dried with a label clearly stating "Best Use Before Sept. 2008" Richard, you need to rotate stock.

bumper

[[email protected]]

Now that's not fair. I know for a fact that Richard turns his stock on the shelves through 90 deg every third Thursday in the month.



On Wednesday, May 14, 2014 9:55:14 PM UTC-6, Eric Bick (1DB) wrote:
> I'm trying a portable FLARM unit for first day today. Two issues on fitting it into the cockpit arose (I fly a Pegase101A).
>
>
>
> 1. There is insufficient room between panel top and canopy for both antennas to stand up straight. If I put the unit so the taller antenna is on canopy centerline, then I can get both antennas up at about 15 - 20 degrees off vertical.
>
>
>
> Question 1 is whether this off-angle is an issue or not for xmt/rcv. Articles I've read indicate it well might be.
>
>
>
> 2. I can't see the tow plane out the front over or around the unit. The panel top is pretty close to the canopy (hence the antenna issue), so adding the height of the unit obscures the view out front terribly.
>
>
>
> Question #2 & 3: So has anyone else (flying a Pegase) found a way around this with a portable unit so that it is still usable? Or is my panel layout/height in cockpit unique? I don't think flying with the FLARM in my lap is the answer, nor is flying tow in a constant slip.
>
>
>
> Eric Bick

[JS]

Probably a typo. The kit has serious claws.
Jim

On Tuesday, May 20, 2014 10:01:14 AM UTC-7, bumper wrote:
>
> I tried the "hinge and cat kit" and found it to have serious flaws.

[Eric Bick (1DB)]

Thanks for the inputs - witty & straight. I got it figured out.
Eric Bick -

[Don Johnstone[_4_]]

At 17:01 20 May 2014, bumper wrote:
>On Friday, May 16, 2014 10:01:11 AM UTC-7, Richard wrote:
>> On Friday, May 16, 2014 9:24:15 AM UTC-7, wrote:
>
>> I sell an antenna with a hinge and a cat. Throw the cat and watch (a
>cat=
> always comes down feet first) then adjust the antenna.
>>=20
>>=20
>>=20
>> Richard
>>=20
>> www.craggyaero.com
>
>I tried the "hinge and cat kit" and found it to have serious flaws. The
>hin=
>ge was loose so the antenna flops around in turbulence. Not being a
>helicop=
>ter pilot, I found it difficult to stay in a tight thermal while using
>stic=
>k and rudder trying to keep the antenna up straight. The cat didn't help
>mu=
>ch, the one I received was freeze dried with a label clearly stating
"Best
>=
>Use Before Sept. 2008" Richard, you need to rotate stock.
>
>bumper
>
You need to ensure that the cat is supplied by Schrodinger, it is then
vertical and not vertical at the same time, and you do not need to feed it.

[Mark628CA]

Schrodinger's cat is an excellent example of a situation where time (the fourth dimension) is not considered. The cat is in a box. You don't feed it. Eventually, the question of live or dead reaches an inevitable conclusion. I am not sure how this relates to soaring, but I am sure that some pedantic OCD participant will clarify.

To reply to the original poster, I have a Pegase with the Core PF installed.. I don't like the antennae in my view, so I fabricated a couple of simple brackets from Adel clamps and plastic that mount to the instrument panel support tubes and hold the antennae vertically, protruding through holes bored through the glare shield.

You might consider using your portable mounted behind the panel with brackets available from Cumulus Soaring and use short adapter cables to the antennae.

FYI, I flew a 530 km flight yesterday from Moriarty, while dealing with a transponder malfunction (fixed now) and I saw all the XPDR equipped sailplanes, Flarm users and "heavy iron" that used ADS-B or Mode C equipment. I felt comfortable with the information I was receiving from the Power Flarm, as I was aware of traffic in the vicinity long before I was able to acquire the target visually. In every case, the Butterfly display gave me indications of aircraft I often did not see for several minutes after getting an alert or just a traffic indication.

I found that a quick glance at the Butterfly was enough to give me an indication of where I should look for the traffic that showed on the BF. Generally, I was able to pick up a visual track quickly. I only had trouble with XPDR Mode C, as no bearing is available. However, the altitude differential as displayed, along with the Black vs. Red range circle was helpful in determining whether the contact was at or near my altitude, climbing or descending and whether it was approaching or retreating from my position.

As I get used to the Power Flarm, I am able to get a quick reading on possible traffic conflicts, most of which I would have been blissfully unaware. I also spend MORE time with my head out of the cockpit, and with a sense of where a possible conflict might appear.

This is cool technology. I highly recommend it.

Mark Mocho
MSM