PCAS collision avoidance

[robin]

Quote:
Look at the proposal for Jersey Zone, for example. In future when you ask for a Traffic Service it will be downgraded to a Basic Service - ie non-radar derived information.
I missed that. How can that be? All traffic in the Jersey Zone is special VFR, which means positive control (and seperation) by ATC. How could you get a traffice or basis service while ATC provides seperation?

Is the proposal to downgrade the class A?

I totally missed whatever it is you're refering to. A link would be much appreciated

dp

http://www.pplir.org/images/stories/...seyatsocas.pdf

[Sciolistes]

I used to use Zaon PCAS (the cheap and highly transportable one). It is good, but not the be and end all. If you rent aircraft then you may have issues with false alerts. The reason is that the unit makes assumptions about attenuation of the signal to determine range and sometimes thinks the host aircraft's transponder is a threat. Once you have figured out the best placement then it should be OK or else the host transponder is weak and needs a seeing to.

No issues in my cub though, no tranny I have to say by and large it didn't detect that many other aircraft that I wasn't aware of from R/T, in the time (albeit just a few months) I flew with it there weren't any significant threats. It was certainly reassuring when in IMC to get traffic information and then see it on the PCAS.

[europaflyer]

One of the major arguments against PCAS is that there is no way that all aircraft can be fitted with transponders, or that the unit will function reliably. I started this thread about PCAS, but how about now looking at the possibilities of FLARM? It is a low-power unit, which is quite cheap, and could certainly be installed in all aircraft - and provide a reliable traffic warning all the time. How about trying to get this made mandatory? If GA took the initiative on this one (it is, after all, mainly of benefit to us) then it would be ages before the next attempt by anyone to get us to fit expensive and useless equipment. FLARM may also be able to provide warnings in airliners. I certainly dont think we should base our opinion on the post from 'vihai', unless he gives us more reasons.

Surely FLARM is what we've been looking for?

[philipnz]

I use a Zaon XRX and swear by it but it does have it's limitations

Firstly of course it relys on other aircraft having their transponder on and it amazing how many GA aircraft you see in TM zones that don't and i'm not talking specials but cessna 172's etc

secondly it does pick up yourself when you alter course and sees you as a threat, that can get a little annoying but easily dismissed as it appears very close out of the blue......

......which means it is of limited use in the circuit. you just get too many warnings and convince yourself you have another or multiple aircraft within feet. It actually freaks me out.

It is fantastic though approaching an airport and transit lanes, high use areas.

[Rod1]

As I said in my previous post I am very keen on FLARM. It is far lower cost than a transponder and PCAS, it is portable, battery powered and light. Almost all flying machines could carry it today. It has limitations in terms of range, but it is proven to work in our environment. There are many other potential solutions, but right now this one appears to be the only likely one if we want high take up.

Rod1

[chrisN]

Vihai of Milano, Italy,

If you grieve for a friend, I am sorry; as you request that we don’t ask you for details, I won’t, but you can’t expect me to take any notice of your objection to Flarm either, when I don’t understand how intellectual property rights can cause a death.

I’m with Rod on this.

Chris N.

[dublinpilot]

Thanks Robin.

So it's only outside the Jersey Zone that is being effected. The zone stays class A, and SVF and full control & seperation service.

Outside, they will only offer a basic service. From memory, they always dumped me once outside the Zone anyway, so I never got a RIS from them.

dp

[europaflyer]

So what we've basically concluded is that PCAS is useful, but has limitations (lack of transponders in many aircraft, unreliability), but FLARM seems to work (in a limited range), the only obstacle being that the idea may never catch on to the extent that there is a point in having one installed.

So a rather contravertial idea - how about petitioning the CAA to make FLARM (or a similar system) mandatory? Midairs would become a thing of the past, and it would greatly improve the image of GA in many eyes. At 500 pounds a shot (or much less when demand picks up) this would seem to be a very real solution to this massive problem.

Who's with me?

[Rod1]

The problem with any system is that it can get you into trouble. In the case of the Staffs incident see and avoid worked, the vintage machine turned to miss the micro and that put it into the path of the turboprop. I think this could happen with any system. If you also consider formation mid airs and Gliders you will never get to zero. The FLARM system could offer valuable assistance, but why not try to get the various bodies to recommend it initially?

Rod1

[S-Works]

I use a Zaon XRX linked to a Garmin 496. Works well enough for my needs which is to give me alerts while I get from a private strip into the airways.

[Fuji Abound]

So a rather contravertial idea - how about petitioning the CAA to make FLARM (or a similar system) mandatory? Midairs would become a thing of the past, and it would greatly improve the image of GA in many eyes. At 500 pounds a shot (or much less when demand picks up) this would seem to be a very real solution to this massive problem.

As I understand the matter there is no generic FLARM. A regulatory authority should not approve FLARM for this reason alone.

It also cannot make sense to have two incompatible systems in use. Transponders are already so well established there is no possibility of FLARM becoming a widespread alternative.

I feel sure that eventually ADS-B or son of will eventually replace both.

[robin]

I feel sure that eventually ADS-B or son of will eventually replace both.

Only up to a point. Our dear friends at the CAA would only permit ADS-B when linked to a fully approved GPS - not a Skymap III/Garmin 196 etc. So although it might well be a good thing, the devil (and massive cost) is in the detail.

[Robin400]

ads-b

Information from my sbs-1 shows how many modern aircraft do not transmit ads-b data. It seems strange that although equipped with mode s transponders, they are not fully configured.

[Rod1]

“Transponders are already so well established there is no possibility of FLARM becoming a widespread alternative.”

Do you think so? In aircraft which typically fly around below 5000ft VFR? I would have thought Transponders the exception. The Micros, LAA, Gliders etc have much bigger numbers and are mostly not Transponder equipped. The CAA tried to force Transponders on them and failed, this is a much better alternative, and you could of course have both in your IFR wonder ship…

Rod1

[Fitter2]

Information from my sbs-1 shows how many modern aircraft do not transmit ads-b data. It seems strange that although equipped with mode s transponders, they are not fully configured.

To feed 1090ES ADS-B info into a extended squitter capable Mode S transponder (most are capable, the Garmin 328 and Funkwerk TRT600 are exceptions) requires the position/vector information to supplied by a IFR certified unit.

The vast majority of GA aircraft don't have appropriate equipment, so won't have ADS-B data.

[421C]

“Transponders are already so well established there is no possibility of FLARM becoming a widespread alternative.”

Do you think so? In aircraft which typically fly around below 5000ft VFR? I would have thought Transponders the exception.

No way. Transponders are the norm in VFR under 5000', not the exception. You do tend to mythologise sport aircraft (gliders, micros etc) as dominating private aviation and I think this simply isn't true. Whatever the number of aircraft is by category, the sporty ones must simply fly less. I don't ever recall a flight in which the majority of other movements I encountered were non-transponder. I am sure there are bubbles of airspace around in which this is the case, but no way are transponders an "exception".

I understand the issue with gliders, but I am confused about micros and LAA. You are always extolling the virtues of these aircraft compared to "spamcans" that will be resigned to history's dustbin. Suddenly a "spamcan" able to carry a transponder and supply it with power becomes a "wonder-ship". Which is it? Are Micros and LAA types able to carry sensible loads and useful avionics, or not?

The CAA was wrong to over gold-plate the transponder requirement with mandatory Mode S for everything. FLARM sounds useful for the hot spots of sport aviation, but a certified technology is the only universal solution. Just squawking Mode C is massively useful to all the TCAS, TAS, PCAS fitted aircraft and ATC SSR and should be encouraged for anyone who can fit one.

brgds
421C

[europaflyer]

So, the bottom line...

Is there a system superior to the FLARM-type system, which A) does not require a power source other than battery, B) costs as little as the FLARM and C) is always effective in alerting to nearby traffic?

If there is, then tell us about it. However, I havn't seen one - transponders and their receiving equipment are costly (particularly the active receiving boxes - 10,000-pounds) and consume a lot of power. ADS-B and ADS-B receivers will probably be similarly expensive and power-hungry. Neither, as far as I can see, could form a system capable of being fitted in all light aircraft at a low enough cost.

There will always be some new 'wonder unit' just around the corner. But some time, we need to take the plunge and settle on one type of unit. I understand that there are a number of companies producing FLARM-compatible equipment, so there is no monopoly problem. Maybe making them mandatory is a bit radical, but strongly encouraging their use by various means, perhaps followed by making them mandatory, would seem to be a good idea. They seem to be proven in the gliding community.

Any thoughts?

[IO540]

Of course there is no such box but you knew that

The point here is that technologies exist which are a lot better than the traditionalist-favourite Mk1 eyeball.

If people who can have transponders (the great majority of planes that actually fly for real, and I don't mean the 1-in-a-million Thruster pilot/adventurer who flew all the way to Kahtmandu) put in a straight Mode C unit, we would get

- a meaningful RIS, without the useless "level unknown" majority of reports

- TCAS activation in commercial aircraft, protecting GA's interests against the regulators

- TCAS activation in private aircraft whose owners have chosen to spend the money

- less resistance to CAS transits

- less resistance to CAS expansion (to a large degree because non-mode-C traffic flying under CAS has to be assumed to be OCAS, and thus far the luck in that daft assumption has held up, despite the hundreds of known CAS busts each year...)

As 421C says, it is completely misleading to suggest that non-powered ultralights or whatever make up the majority of GA. They do occassionally bust some piece of airspace as a group of 20+, all flying together, but that isn't quite the same thing

[Fuji Abound]

Trig TT21 Transponder

Very small, and compact, minimal power with battery power only around the corner. Combine the new generation of mode S units with PCAS and a TAS system is a reality. Price is still a factor and FLARM clearly has more than the edge in this respect, but sadly aviation was never cheap - but you knew that anyway.

[bookworm]

Is there a system superior to the FLARM-type system, which A) does not require a power source other than battery, B) costs as little as the FLARM and C) is always effective in alerting to nearby traffic?

FLARM has low power consumption because it transmits at low power and is therefore low range. It costs less than a transponder because it does not meet a certified standard. If you mandate FLARM, and therefore require certification, and increase its power to something more generally useful, you end up with something that is as expensive and power hungry as Mode S.

What we need is a low power, uncertified system that works over 1090ES and is therefore compatible with the vast installed base of Mode S and TCAS.