Flarm

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C Rule
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Flarm

Post by C Rule » Wed Mar 22, 2017 9:53 am

I fly in airspace with in excess of 300 gliders based within 50NM of my base Popham. On a fine weekend day a significant number are off flying cross country. It is a known fact that they don't show up well visually when head on. The vast number of them are equipped with FLARM and talking to glider pilots they report it is a great aid to collision avoidance.
Does anyone have any experience of operating FLARM/PowerFlarm in our types of A/C?
Colin Rule
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Ian Melville
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Re: Flarm

Post by Ian Melville » Thu Mar 23, 2017 12:06 am

I have a Flarm mouse and have been disappointed at the range that it will see gliders. Not used it enough to form a firm opinion yet, it looks to have it's best range at about 3km. antenna installation is absolutely critical, but difficult to do in GA aircraft. Despite the fanfare from Flarm many gliders still do not have it fitted.
Power Flarm has a more powerful transmitter, but you will see gliders at the same distance.
Ian Melville
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C Rule
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Re: Flarm

Post by C Rule » Thu Mar 23, 2017 9:22 am

Ian.
My understanding was that Flarm only alerted for traffic who's vector was going to produce a collision or near collision (just miss) and was not intended to be a PPI "radar"
Cheers
Colin
Colin Rule
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Ian Melville
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Re: Flarm

Post by Ian Melville » Thu Mar 23, 2017 5:06 pm

I wonder if I have misunderstood something? I though that would depend on your display type? I am watching the data stream from the Mouse, which I understood to be all FLARM traffic it detects, hence can be used as a pseudo Radar :-)

From the Mouse Manual
Display of nearby FLARM traffic with warning visually and acoustically of approaching other aircraft or fixed obstacles (where database has been installed)
intelligent motion prediction which minimizes nuisance alarms and supports situational awareness
From that, I read that it displays all traffic it detects, but give additional visual and audio alerts to traffic it deems to be in conflict.
The FLARM data port specification supports that with messages that have no threat level.

My display does not use the algorithms developed by FLARM, because they were developed for gliders, not GA.
Ian Melville
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C Rule
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Re: Flarm

Post by C Rule » Fri Mar 24, 2017 3:02 pm

Ian
I think it proves that all the traffic avoidance aids are just that and in the end it comes down to a good look out and the Mark 1 eyeball
Colin
Colin Rule
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Ian Melville
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Re: Flarm

Post by Ian Melville » Fri Mar 24, 2017 6:45 pm

Absolutely
Ian Melville
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gdbird
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Re: Flarm

Post by gdbird » Wed Apr 12, 2017 7:24 pm

I have a PFLARM core in my Europa and am based next to London Gliding Cub.
So I transmit FLARM, Mode S, and ADS-B. I am very pleased with it.
I use skydemon on a nexus to display traffic and it shows a small planes, a line with their track with distance markers and the height difference in numbers. You can set the band of similar height interest.
The PFLARM core picks up Mode S/C, ADS-B and FLARM. Mode C traffic is displayed as circles around ones position; green, white or red.
I submitted an airprox recently having seen the whites of a C152s pilot (and instructors) eyes near Booker.
They had elected to keep their transponder switched off.
Graeme Bird
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C Rule
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Re: Flarm

Post by C Rule » Wed Apr 12, 2017 8:31 pm

Its very interesting to hear from a PFlarm user .
I would be interested to hear where you mount the various aerials you need with the PFlarm core. I had thought of using a PF portable . I was put off the Core because of the need for external aerials and the need to submit a Mod.
Colin Rule
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gdbird
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Re: Flarm

Post by gdbird » Thu Apr 13, 2017 3:11 pm

There is a baggage bay wall in the Europa behind the seats, the core module is fixed to that; I have bonded one antenna is to each side of the GRP fuselage and the GPS antenna overhead. I didn't submit a mod, didn't think one would be required. A Butterfly unit transmits the serial messages to the nexus via Wifi. All the core needs is 12V.

Sometimes a mass of gliders are displayed like a swam of bees and you still cant see them with your eyes. Similarly planes are reported a couple of miles away and nearly always impossible to see them.
Graeme Bird
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C Rule
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Re: Flarm

Post by C Rule » Fri Apr 14, 2017 5:17 pm

Graham
Many thanks for the information. I have a metal airframe (RV6)
I will give some thought to how to use a PFcore as I think the range will be better than with a PF portable.
Cheers
Colin
Colin Rule
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Rob Swain
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Re: Flarm

Post by Rob Swain » Wed May 03, 2017 3:51 pm

If you have a definite, pressing and immediate need to see gliders then I guess PowerFlarm is the expensive answer.

However...

PilotAware is gaining a form of Flarm detection.
http://forum.pilotaware.com/index.php/topic,885.0.html

This is in addition to all the PilotAware/P3i, ADS-B, Mode S and Mode C conspicuity with display on your tablet GPS navigation system of choice!

Yes, this latest development will require some buy-in from gliding clubs, airfields and other ground stations, but in the name of conspicuity the will seems to be there!
More than can be said for certain other parties: I'll say no more as it will only get 'moderated' (and probably correctly, from a purely legal standpoint)!
Rob Swain
If the good Lord had intended man to fly, He would have given him more money.

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Re: Flarm

Post by [email protected] » Thu Jul 13, 2017 10:53 am

Keith Vinning
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AlanB
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Re: Flarm

Post by AlanB » Mon Jul 24, 2017 7:51 pm

I operate between Lasham, Wycombe and Abingdon Gliding sites and have a PFLARM in a Europa mounted in the rear like GBird describes with a clear view of the area around the airframe. I also broadcast Modes S and ADS-B out.

The display is via a V3+ unit which provides indications of targets potentially in conflict and also I can feed the data to my Panel mounted GPS via a serial connection for an overall view. Both are in my line of sight while scanning outside.

Very pleased with the result and have detected gliders and other traffic at descent ranges but am dismayed at the number of visually acquired targets who appear not to have anything thransponder wise turned on.

I have tried various portable devices but find that unless the antenna is mounted away from the pilots and engine there is too much screening of the signals and a detrimental effect on range. Hence why I settled on PFLARM and permanent mounted antennae in the rear of the fuselage.
Alan Burrill
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GrahamFraser
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Re: Flarm

Post by GrahamFraser » Mon Sep 04, 2017 2:50 pm

Very interesting topic, I have for many years flown gliders both in the UK and in the French Alps. Flarm in the Alps is essential and I can vouch for its benefits as trying to see a glider against a mountain head on at 200 knots closure is tricky!

Having moved across to GA (now flying an RV8) with no collision avoidance I feel somewhat vulnerable and have been looking into the various options. With the all metal build of the RV I believe the aerial location of a permanent fit is essential but costs for Power flarm etc are high and the portable version is appealing. As GA tends to use transponders and gliding uses Flarm a system that covers both is critical and it looks to me that Power flarm is the only current viable option but how will it work on an all metal airframe?

Any further thoughts on this as the technologies is moving on fast with the likes of Skydemon and Runway HD offering a FLARM option on there moving maps which is appealing.

C Rule
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Location: South of 70 north

Re: Flarm

Post by C Rule » Mon Sep 04, 2017 8:36 pm

Graham
I have mounted a Power Flarm portable on the coming of an RV6. I out put it to Skydemon on a Ipad mini on the panel so get both head up and head down traffic information. I find it works very well. Checking on the Flarm website and using the range analysis tool I find the polar diagram of the portable aerials is satisfactory. The new firmware for FLARM Ver 9.4 if memory serves has introduced the ability to plot the aerial response in both planes.

Colin
Colin Rule
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