Mode S meeting with CAA

[bookworm]

But in airspace where TCAS carriage is not mandatory, the majority of other aircraft have no way of detecting you.

Of course they do. You can buy a number of simple transponder detectors for a few hundred quid. As the carriage of transponders becomes more widespread, the sophistication of such devices will increase and the price may fall.

Maybe we should have a regulation for all Commercial flights operating outside CAS to have airborne radar fitted - it is proven technology, it would be paid for by the beneficiaries,

They do have radar fitted. It's called TCAS. But it's a secondary radar, and it needs cooperation from the other aircraft flying in the space. Suggesting that they carry primary radar is analogous to suggesting that they should carry massive searchlights capable off lighting up other aircraft in their path to save the others from having to display lights.

[Rod1]

bookworm

“But in airspace where TCAS carriage is not mandatory, the majority of other aircraft have no way of detecting you.”
“Of course they do. You can buy a number of simple transponder detectors for a few hundred quid. As the carriage of transponders becomes more widespread, the sophistication of such devices will increase and the price may fall.”

If you are saying that the majority of airspace users carry such devices now then I think you live in a very different world to me! Most airspace users could not carry such devices if they wanted to,

Rod1

[QDMQDMQDM]

Indeed it's not. It exists for exactly the same purpose as mandatory transponder carriage: so that other aircraft can detect you in time to avoid a collision.

Oh you narrow person. Not everyone is operating in CAS and this regulation throws up endless absurdities like a Luton Minor in remote North Devon being unairworthy because its Mode S transponder isn't working. It's unenforceable and for the majority of us pointless. And anyway we don't have a big problem with mid-air collision in this country.

[bookworm]

If you are saying that the majority of airspace users carry such devices now

No, I'm not. I'm saying they could, which appears to be at odds with

Most airspace users could not carry such devices if they wanted to

Why not? The current generation are light, battery-operated and reasonably effective. They're not TCAS, but they're out there and available.

[bookworm]

And anyway we don't have a big problem with mid-air collision in this country.

Well let's just send NATS packing and save us all a lot of money, shall we?

If you're not prepared to play along to de-risk sharing the airspace, commercial air transport, whose operators believe that there is a problem with the potential for mid-air collision, is simply going to grab more and more of the air until you have nowhere to fly your Minor. And Joe Public is going to be with them all the way.

[Rod1]

“The current generation are light, battery-operated and reasonably effective.”

OK, well the one I have looked at (which the owner sent back as it was not much good) was about 2kg and quite big. If there is a new generation the size and weight of a mobile then I stand corrected.

Rod1

[Single Spey]

If you're not prepared to play along to de-risk sharing the airspace, commercial air transport, whose operators believe that there is a problem with the potential for mid-air collision,

I'm all for de-risking sharing the airspace - as I said get all commercial operators to fit an airborne primary radar. As you say, they are the ones who believe there is a problem.

To put your points into another perspective - passenger trains have been known to hit vehicles on level crossings. So, lets mandate that all privately owned cars must fit a transponder that alerts a train driver to the presence of a vehicle on a level crossing in enough time for him to stop. De-risking the journey for the fare paying passenger as you would describe it. Alternatively we should embark on a programme to close all level crossings and force private vehicles to make a detour.

[QDMQDMQDM]

Spot on, Single Spey.

Tell you what, bookworm, why not mandate Mode S for everything that flies AND add in the requirement for a VFR flightplan for every flight, like they do in Spain. That would give even more 'de-risking', wouldn't it?

[Rod1]

CAA presentation now available at;

http://www.pfa.org.uk/

Rod1

[tmmorris]

Are Mode S transponders self-monitoring?

If not, and you fly NORDO (and no-one is proposing mandatory radio carriage or use OCAS) how do you know if it's working?

Tim

[IO540]

You don't know.

But let's face it, your existing Mode C doesn't get checked unless some ATC unit tells you that you are at 65,000ft and should descend immediately

[JBGA]

Perhaps the ideal hardware doesn't exist right now but don't you think that when the CAA/EASA publish the technical specifications, avionics companies will be clambering over each other to produce new equipment designed specifically for our requirements? After all, if everyone is going to have to buy one there is a HUGE potential market and competition will be strong.

I'm certain that by the time this all happens in 2021, Mode S transponders will be the size of a fag packet, will run for several days non-stop on a single charge and probably include traffic awareness information to help us stop bumping in to each other. And they will all be 'ADS-B Ready' which opens up a whole world of possibilities like availability of real-time graphical and textual weather and 'Virtual radar' etc. in the cockpit.

[JBGA]

But let's face it, your existing Mode C doesn't get checked unless some ATC unit tells you that you are at 65,000ft and should descend immediately

Reminds me of that little anecdote about a Scottish controller who recieves a request from a private aircraft to change to FL650. Thinking the chap has made an error he wittly asks 'How are you going to get up there then' and the response comes 'We're not.....we'd like to DESCEND to FL650 please'. Yep, it was an American U2!

[IO540]

So much bull in this thread.

Spain requires flight plans for VFR only for flights in controlled airspace. Look in their AIP, rather than propagate this disinformation yet again.

Airborne radar which can pick up other aircraft is massively expensive. Only some military planes have it.

The case for transponders in GA is to ensure that TCAS systems carried by commercial traffic (this is mandatory for anything of any size) can detect the GA aircraft, should it get too close. And 'getting too close' usually means somebody got lost and busted controlled airspace. Had there been no CAS busts I doubt we would be seeing this situation, but they continue because lots of GA traffic is unable to navigate.

A small piece of the case for transponders is that some commercial traffic also flies in Class G. One can moan about this but the obvious solution is to have more controlled airspace! Now, do you want more CAS, or mandatory transponders?

Now, to trigger somebody's TCAS one needs only Mode C; no need for Mode S. If Mode C had been made mandatory years ago, or the UK and Europe adopted US-style Mode C veils around major airports, the fuss would have died down long ago and GA would probably not be compelled to fit Mode S.

But, GA has successfully lobbied against transponders and when it finally lost the battle (the Mode S battle is now lost; it's just a matter of time before they are a practical must-have for VFR or IFR touring) Mode S was the technology of choice because it enables ATC to selectively interrogate traffic.

IMHO it is unnecessary to mandate Mode S for the sector of GA that carries Elementary Mode S (basically anything below 250kt TAS and below 5700kg; above these Enhanced Mode S is required) - Mode C would have been perfectly fine and would have delivered most of the benefit to ATC. But this is what we have and we are stuck with it.

[robin]

>>>Perhaps the ideal hardware doesn't exist right now but don't you think that when the CAA/EASA publish the technical specifications, avionics companies will be clambering over each other to produce new equipment designed specifically for our requirements? After all, if everyone is going to have to buy one there is a HUGE potential market and competition will be strong.

I'm certain that by the time this all happens in 2021, Mode S transponders will be the size of a fag packet, will run for several days non-stop on a single charge and probably include traffic awareness information to help us stop bumping in to each other. And they will all be 'ADS-B Ready' which opens up a whole world of possibilities like availability of real-time graphical and textual weather and 'Virtual radar' etc. in the cockpit. <<<<

Oh you optimist, you

The CAA has been working on Mode S for around 15 years and we still don't have a spec. The CAA will not do so, as they consider the market will develop one.

I have lost count of the times I've been told that the low-powered, small, low-cost TX is just around the corner. It isn't

[Rod1]

“the Mode S battle is now lost; it's just a matter of time before they are a practical must-have for VFR or IFR touring”
I do not think anybody thought that some sort of box would not be mandatory at some point in time, so the battle was about timeframe and what box.

It will be possible, for sure, to tour in the UK, post 2012 without a transponder. It MAY be possible to tour parts of Europe, nobody knows for sure at this time. If this situation continues for a small number of years post 2012, then we will be talking about fitting ADS-B, so the requirement for Mode S may never happen.

The aim of the lobbying was to remove the requirement for all flying machines to have a Mode S box by 2005 (I think this was the original date). The current situation is you do not need Mode S to fly, so we have already won!

The future is still open and no date has been set for a requirement to fit Mode S to everything. The second consultation is coming soon, take part! The longer the debate goes on, the cheaper the box we eventually have to fit will be.

Rod1

[mm_flynn]

Don't get hopes up around ADS-B. In the US for CAT and high altitude flight it is just Mode-S ES with GPS/FMS fed extended squitter - and this is what Europe has indicated it will go for. The US (lobbied extensively by AOPA) are also going for ADS-B based on UAT, which will provide greater bandwidth and allow uplinking of weather METARS, etc (i.e. the same stuff they up link with TIS).

So, going to ADS-B probably will mean, a software upgrade to your Mode-S transponder, and approved GPS for position data (maybe Galileo with a mega£ subscription just to p!ss people off , and maybe some major mod paperwork.

[IO540]

I agree ADS-B is a loooooooong way down the road in Europe.

"The longer the debate goes on, the cheaper the box we eventually have to fit will be."

Possibly. The problem is that a minor transponder manufacturer will wait until they are mandatory before out something too revolutionary. This is because the company which owns the market (Garmin) could knock out a cheap Mode S very fast, if they thought there would a lot of demand, so if a small mfg brings one out they will have to move fast. If they play their card and the units are not made mandatory, they will just sell the usual low volumes (made lower still by the massive loyalty to Garmin in the avionics distribution / installation pipeline) and then Garmin will come along and kill them (or buy them and then kill them ).

Garmin haven't done anything, most likely because there is enough demand at the current ~ £2000 price. But they could.

However, if/when transponders become mandatory then price will not be important because you will have to buy one anyway

So there is really no case for waiting, unless one's flying pattern is entirely in airspace which doesn't need one.

[tggzzz]

Mode S in gliders

The batteries required to drive a transponder, for several hours flying, would weigh several kilograms

That's quite incorrect and is just another Mode S scare story going around. My GTX330 draws about 0.5A at 28V. Two little sealed lead acid batteries in series would weight about 1kg total, dimensions 140x80x20mm (I have one in my hand) and at 2Ah would drive the unit for about 4 hours. But this is old technology and a laptop-type lithium battery would do several times the time for about 1/3 the weight; I have one of those in my hand too.

1) gliders regularly stay up for much longer than 4 hours. In addition, they are frequently used continuously during daylight hours for training (and just plain fun, mustn't forget that!).

2) do your power consumption figures include being interrogated at realistic intervals?

3) lithium ion batteries have a reputation for spontaneously igniting quite spectacularly. Look on YouTube for some videos.

Does anyone know what (airliner cabin crew are trained to do if a laptop starts burning?

[JBGA]

Originally Posted by IO540

The problem is that a minor transponder manufacturer will wait until they are mandatory before out something too revolutionary

I don't see the problem with that. The government will approve the proposals at the end of next year. Carriage won't be mandatory until 2012 (According to current proposals). That gives manufacturers around 4 years to come up with something. And all we are talking about is taking an ordinary Mode S transponder (Of which there are already several manufacturers) and making it a bit smaller and lighter and probably battery powered. Hardly 4 years worth of work. This is going to be red letter day for transponder manufacturers so they probably have ideas on the table for how to accomplish the task already.

The weakest link is EASA and the time it takes for them to approve specifications.