Portable Collision Avoidance Systems

[mattd_C152]

Folks

Does anybody have any experience of the Zaon Collision avoidance systems? if so how good are they? do they become a pain when flying in the circuit or do they pick up that aircraft that is cutting into the circuit? i know they rely on the transponder squawking mode chalie and i know theres no substitute for the old MK1 eyeball, but nobody is infallible. I'd be looking to use one as a stand alone piece of kit.

[Rod1]

Get hold of a copy of the Summer 09 edition of flyer. There is an article that covers this in some detail, including a flight test of the Zaon. The short answer is quite good.

Rod1

[Fuji Abound]

Well worth using the search function as this one has been done to death.

[XX621]

Yes it has been done to death, but here's three brief pointers from my use.

1. Recently had to send mine MRX unit back as it developed a fault (plastic bit fell off) -got it back within 10days and they had upgraded and replaced the case for the newer design :). Excellent customer service, I liaised with only person who took personal ownership of the process.
2. It's a real eye opener (no pun intended) how much traffic is out there not transponding, I frequently visually identify Cessnas/Pipers within the range of the unit and no report on the unit at all.
3. It can be a distraction, you have to be manage the attention you give it, and be very clear on how to interpret the information.

Hope helps:ok:

[englishal]

I have the XRX interfaced to the G496 and it works very well.

[Ryan5252]

" Recently had to send mine MRX unit back as it developed a fault (plastic bit fell off"

I hear the plastic bit is critical to the whole operation of the unit! :\

[MichaelJP59]

I've had the MRX a couple of weeks now and I like it even though non-transponding traffic doesn't show, if nothing else it reminds you that you're not the only one in the sky even if you can't see anyone! As you say though, build quality is suspect, I had to get a new aerial and retaining nut after the first one just wouldn't stay on.

Also just got to read Rod's article - interesting stuff, Rod, and the combined unit mentioned including ADS-B and FLARM would be great in the panel.

[SNS3Guppy]

The XRX is subject to a lot of potential errors, and it's very easy to get wrapped up in gimmicks in the cockpit that distract from the more important task of flying the airplane (and looking for traffic). That said, I've had at least four recent near mid-air's of which I was alerted using a Zaon PCAS. Each occurred at night in areas with poor control and an unusual method of control, and in each case I would have had no way of knowing about the traffic, save for that unit.

I've also had hundreds of false warnings, "ghost" images, etc. Given the circumstances, I'm very certain the near midairs (which were same altitude, less than a tenth of a mile) were genuine warnings. In two of those encounters I saw the other aircraft in the dark...one as it's wing passed under mine.

My assessment is that it's better than nothing. I'm more familiar with TCAS equipment, and the PCAS doesn't come remotely close to the quality and capability of TCAS...but it doesn't come close to the cost, and is a whole lot easier to install, too. Realistically, few (if any) are going to install TCAS in their light single engine airplane...but PCAS offer an option.

An important difference with PCAS is that it's not active; it's passive. Whereas TCAS interrogates other aircraft's transponders, PCAS does not. If you're not in an area where other aircraft are being interrogated by either ATC radar or TCAS units, then you won't see them on PCAS.

[Fuji Abound]

If you're not in an area where other aircraft are being interrogated by either ATC radar or TCAS units, then you won't see them on PCAS.


Not much of a problem this side of the Pond.


I've also had hundreds of false warnings, "ghost" images, etc.


You were probably using one of the earlier units. I have run mine alongside TAS and over around 10 hours I did have a single false warning.

[englishal]

The XRX is subject to a lot of potential errors
Mine seems very accurate and displays the traffic on the 496 very accurately.

Perhaps it is how you have it mounted?

[Rod1]

“very easy to get wrapped up in gimmicks in the cockpit”

Provided you are using the unit in VFR, and use the audio to get you to look out the front before you look at the unit (as per the recommended use), this should not be a problem.

Rod1

[IO540]

One must not take these baits.

This "head down in the cockpit playing with the knobs" has been done to death.

If the ZAON directional unit could be mounted out of sight, I'd go for it too. Presumably it needs to have a direct view around, not obstructed by metal.

I looked into getting the full Ryan/Avidyne 600 system installed, a few times (£10-15k) but could not bring myself to have the plane taken apart over several weeks, with the relocation of most of the existing antennae and rewiring etc. Right now everything is working perfectly and I don't want to mess with it :)

[Heliplane]

In short, it's not a bad unit - I'd even venture to say it's pretty good. The distances shown are slightly suspect but the general direction of traffic and altitude has been pretty accurate. We bought one between 4 of us for our group aircraft so it was not a serious financial outlay. I'm not sure whether I would have spent £1k on one alone though.

It has shown traffic that I have not picked up with my eyes but it has also not picked up traffic that I have otherwise seen (perhaps these aircraft were not transponder equipped).

Personally, and some may disagree, I think the best traffic avoidance measures are, in this order:

1) The pilot (keeping a good lookout, flying at proper altitudes - although nobody seems to do this in the UK - alternatively flying at strange altitudes such as 3,700 as opposed to 3,500 or 4,000). Fly to the right of roads, tracks, etc. Keep your lights on.

2) Radar services - no reason not to always request at least a traffic service. I usually get this service provided it is not a Sunday.

3) Devices like the Zaon.

[Fuji Abound]

1) The pilot (keeping a good lookout, flying at proper altitudes - although nobody seems to do this in the UK - alternatively flying at strange altitudes such as 3,700 as opposed to 3,500 or 4,000). Fly to the right of roads, tracks, etc. Keep your lights on.




and some may disagree


I am one of those some.

Flying at odd altitudes has been done to death. Nearly everyone does and you are probably better not flying at odd altitudes.

Most pilots dont keep line features on their left. In fact if you fly regularly along the coast you will find regardless of what direction they are going they fly just off the coast for the views. I am not even convinced how many people know the "rule" or, if they do, are aware they are flying along a line feature.

See and avoid doesnt work when you need it most - you will see all the ones that just miss you but you will not see the one that is going to hit you.

In my view anyone who believes in see and avoid should go fly with someone who has TAS - it is an eye opening experience (excuse the pun :ok:). You will never again believe you can totally rely on see and avoid.

Your other ideas are sound!

If the ZAON directional unit could be mounted out of sight, I'd go for it too. Presumably it needs to have a direct view around, not obstructed by metal.

You can - they do an external aerial and a panel mount kit - although as you know you will never get approval for the panel mount. With the external aerial I dont see the problem mounting the unit somewhere convenient but of course it does need to be vaguely in your line of sight even if the audio function is linked to your headset.

Personally I would never fly without either TAS or PCAS after a couple of bad experiences. Given PCAS is relatively so cheap I think people are nuts not to use technology like this when it is available particularly as it only takes one mid air to almost certainly kill you.

All that said I know the risk is very small so I equally understand those who dont use these units and I recognise my bias arises from a couple of incidents too close for my own comfort. :)

[SNS3Guppy]

Not much of a problem this side of the Pond.

I'm on the same side of the pond as you...just a little farther downrange.

In my view anyone who believes in see and avoid should go fly with someone who has TAS


I have no idea what TAS is..traffic alert systems, perhaps...but I generally use TCAS II...and I'm the missionary of see and avoid. Moreover, it's not just a good idea. It's the law.

Provided you are using the unit in VFR,...


It's very VFR presently, operating under VFR...but night, dark, few references, and a LOT of traffic, much of which isn't reporting, much of which can't. Simply being VFR means very little...because a VFR night here is still hard instrument conditions.

You were probably using one of the earlier units.


I was not.

I have run mine alongside TAS and over around 10 hours I did have a single false warning.


I have run them for several hundred hours in a variety of different aircraft and different units...not earlier ones...and have had hundreds of false warnings.

[englishal]

I'd be happier if we could fly at proper semi-circular altitudes in the UK, and everyone stuck to it. Unfortunately airspace prohibits this in certain areas and where it doesn't we have this silly quadrantal rule.

This "head down in the cockpit playing with the knobs"
So you saw the video of the porn star and the helicopter pilot over San diego too :}

[Fuji Abound]

I'm on the same side of the pond as you...just a little farther downrange.



I was going by your profile.


and a LOT of traffic


downrange of the UK at night VFR - I doubt that very much.

I have run them for several hundred hours in a variety of different aircraft and different units...not earlier ones...and have had hundreds of false warnings.

If that is so why would you persevere with an obvioulsy faulty unit that clearly is purely a distraction. If I were you I would send it back and have it replaced under warranty or check to see if there were issues caused by the aircrafts you are operating - you have read the manual that came with it, have you?

[Rod1]

You get any PCAS system to give faulty alerts and advisory’s by simply arranging for iffy power. If you use the small unit and rechargeable you get about 4 hours, and then it will give you lots of spurious results. Hardly a fault it the unit though.

Rod1

[Fuji Abound]

You get any PCAS system to give faulty alerts and advisory’s by simply arranging for iffy power.


Why would you do that?


If you use the small unit and rechargeable you get about 4 hours, and then it will give you lots of spurious results.


Presumably after ignoring the low battery warning.

Hardly a fault it the unit though.

True. Maybe that is SNS3Guppy's problem - low batteries or iffy power - anything is possible I suppose if you try hard enough.

[SNS3Guppy]

If that is so why would you persevere with an obvioulsy faulty unit that clearly is purely a distraction. If I were you I would send it back and have it replaced under warranty or check to see if there were issues caused by the aircrafts you are operating - you have read the manual that came with it, have you?


I don't get to choose what's put in the aircraft. I get assigned, I fly it. It's that simple. And yes, I've read the manual. It's on this computer, in fact.

downrange of the UK at night VFR - I doubt that very much.


What you believe or doubt is very much irrelevant.

It's also very much night VFR here, no matter what the conditions. We're somewhat southeast of you.

True. Maybe that is SNS3Guppy's problem - low batteries or iffy power - anything is possible I suppose if you try hard enough.


I certainly don't try to make the unit fail, and it's hardwired into the aircraft power. Batteries are not an issue.

The PCAS is better than nothing, but just barely...and where it may lead one to distraction, it may be worse than nothing in some cases.

I was going by your profile.


I'm international. Always have been.

[englishal]

but just barely
You shoudl check your installation then because I have the XRX interfaced to my G496 and in my experience it is very accurate, and often shows me traffic I haven't seen, as part of my normal instrumentation/GPS scan.

[Fuji Abound]

and it's hardwired into the aircraft power.


In which case it is probably an illegal installation. :) I wouldnt just accept what is in the aircraft either, it is your responsibility as commander to "accept" the aircraft or otherwise. I wouldnt "accept" an aircraft with a "TAS" installation that is giving as many erroneous readings as you suggest - I would want the unit placarded u/s.

However in the event I would have the operator replace the unit as it is clealry faulty and not representative.

[SNS3Guppy]

In which case it is probably an illegal installation.


No, it really isn't.

I wouldnt just accept what is in the aircraft either, it is your responsibility as commander to "accept" the aircraft or otherwise.


There are probably a lot of things you would or wouldn't do, and you have the luxury of doing that.

Here in a combat zone, it's a little different.

[englishal]

WOW, do they use the Zaon in combat zones? I can't really see the Eurofighter with a Zaon sat on top of the dash :} I'm sure we have IFF transponders in our military. Must be Obama's defence spending cuts :}

[SNS3Guppy]

It's not in a eurofighter, and it's an easily procurable, replacable supplementary device...with which I'm not impressed.

[Pugilistic Animus]

In my view anyone who believes in see and avoid should go fly with someone who has TAS


I hope you mean as an adjuct to see and avoid it even applies in 'VFR' conditions with TCAS I or II on TA mode





Here in a combat zone, it's a little different


You Stay Safe over there y'hear SNS3Guppy:)

PA

[Rod1]

When I did the 3500 words for flyer on this I did some research. Of the people I spoke to a very small number had had trouble with spurious alerts, and about ½ of these had traced it to power. I know from my own experience that this can case the problem, but I have had no issues with mine, which were not attributable to poor power. Having said this the device was intended to be used in GA aircraft, so if you put it in something with a lot of EM interference who knows what would happen.

My local flying club had just bulk purchased some units (at considerable discount) and the comments received back indicate a great deal of surprise at the number of aircraft which were getting close to them which were not spotted until after the unit had detected them. If any of your local flying clubs are interested in a talk on collisions avoidance, I would be happy to oblige as we lose far too many people to collisions and see and avoid needs all the help it can get.

Rod1

[Fuji Abound]

I hope you mean as an adjuct to see and avoid it even applies in 'VFR' conditions with TCAS I or II on TA mode



That I do mainly because I like the scenery. Having flown a fair amount of aeros I reckon my look out is as good as most but I know to my cost it is vey poor at spotting the one that is going to hit you, but not too bad at the rest. The trouble is that doesnt help much.

The great thing about TAS and including a large MDF in your scan which also produces an audible warning is that the combination of old fashion technology (the mark 1 eyeball) and modern technology produce, IMHO, is a far more reliable means of detecting the enemy.


Here in a combat zone, it's a little different.


Hmm cant imagine that much traffic around in a combat zone, I guess you lot arent doing your job very well if you havent managed to supress most of it. :)

[IO540]

Great idea that... I'd like all traffic below 3000ft "suppressed" except under the LTMA where I would like all traffic below 2400ft "suppressed".

That would deal with at least 99% of GA.

[SNS3Guppy]

Hmm cant imagine that much traffic around in a combat zone, I guess you lot arent doing your job very well if you havent managed to supress most of it.


Air superiority isn't an issue with respect to suppressing traditional threats. The real threat are unmanned aerial vehicles, and thus far every incident I've had has been a UAV. The air is thick with them. It's worse in other locations. Unfortunately, radar is sporadic, as is traffic that reports or talks. The way airspace is assigned is very different, too.

In the case of PCAS, it won't detect another transponder unless it's being actively interrogated by either a TCAS unit, or radar. This means that targets can suddenly pop up inside the range settings of the PCAS unit without warning, and disappear, quickly as well. The update rate on them isn't good, which probably isn't a problem if one isn't doing much maneuvering or turning. The unit also delivers only very rough approimation as to azimuth or bearing from the user, and even with the screen displaying a dot for the position of the intruder...the refresh rate is slow enough that traffic is often not where the unit says it is because the angular difference has changed in a turn.

A frequent error I see is traffic appearing to change altitudes. Sometimes it's obvous and rapid, but sometimes not. A change of five hundred feet or so instantaneously can be identified as an instrumentation error, but when watching the traffic being monitored descending a few hundred feet and going back up again...one can't really be sure. In some cases I wasn't sure if the warnings I received were real or not..but a few times now I've verified it visually...in the dark.

Point being...these devices are probably better than nothing, but in my opinion, not much more so. Certainly installing TCAS is prohibitive in most cases, but I think knowing the limitations of the equipment is every bit as important as knowing what it *may* be able to dofor you.

[englishal]

The unit also delivers only very rough approximation as to azimuth or bearing from the user, and even with the screen displaying a dot for the position of the intruder...the refresh rate is slow enough that traffic is often not where the unit says it is because the angular difference has changed in a turn.
I still reckon that the errors you see are either because of your location or the location of the PCAS.

I use mine in the southern UK where there is pretty much 100% radar coverage, and in my experience in straight and level flight the azimuth info in a 270 degree forward arc is very accurate. Update is as per the radar sweep, as per the other day I was flying parallel to the air ambulance chopper and it's position was exactly as indicated on the 496 screen, when they started to descend into their landing site, altitude changed immediately as they went down.

I was taking to a military controller with a traffic service and he warned me of some military aircraft performing instrument training. It was 2000' over cast and the PCAS picked up the two recovering aircraft before they broke through the base of the cloud. The PCAS had told me exactly where they were, I'd been following they yellow spots on the gps screen, and low and behold they appeared as expected.

The only inaccuracies I have experienced tend to occur when the traffic is right behind, and I guess this is due to the "blind spot" of the rear fuselage. The Zaon can determine azimuth to 45 degrees, I guess based upon received signal strength on two of the 4 quadrants of the antenna. It would be better with a hull mounted antenna of course, but what would be even better is if we all fitted FLARM and started squirting our GPS coordinates out.

[2high2fastagain]

Matt, I have the XRX and I always use it when I'm flying. It does seems to give the odd spurious reading and the voice alert system seems to have a habit of cutting in just when I'm talking to ATC. However, I do think it is invaluable and it has picked up a number of close flying aircraft that frankly I was not in danger of hitting, but I was really grateful to know were there.
If you are vigilant and scan with the Mk 1 eyeball obsessively, then the Zaon gives you the odd helpful cue which I think makes you safer. If you rely on the Zaon and don't keep your head outside the aircraft, then it's probably less safe than not having one.

[liam548]

is the XRM a lot poorer than the XRX?