Flying IMC out of CAS now dangerous?
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Pace,
I would love for there to be an easy answer by means of a universal avoidance system, be it FLARM or transponder based. The trouble is that at the moment there isn't. To ban gliders from cloud is difficult to do unless it widely impacts the sport. Yes it's true that few fly in true IMC, but as I asked earlier, how do you legally define between IMC and cloud flying? Also there are times when a glider may have intended to remain clear but has had to fly through cloud to descend (wave flying?).
It's years since I flew gliders, but I did occasionally cloud fly. I also once climbed up the sunny side of cumulous to a few hundred feet above its base whilst staying out of it. It was fairly near a gliding site, so perhaps I was relatively safe, but having seen SEP's fly straight over glider sites at circuit height ... who knows?
I suppose the only sensible way in the meantime is for any glider flying through or in cloud to be in contact with ATC. That way, at lest any IMC aircraft can be warned. In the original scenario, I don't know the answers, but it certainly shows up the failings of flying IMC outside of CAS.
I know flying is expensive, but it shouldn't have to be priced to a point that excludes all but the very rich. I know the aurgument for reducing chances of a middair is complelling. I for one, would not relish the idea of being killed that way, but you still have to weigh up the odds. I think overhead joins present a far far higher risk, but nobody is jumping up and down about them! I'd hate to see all but the richest glider pilots banned from entering cloud. Maybe it will come, but be careful what freedoms you cry out to ban, one of these days it might be one of yours? Old argument I know, but where do you end with the idea of banning all that is not 100% safe?
SS
I would love for there to be an easy answer by means of a universal avoidance system, be it FLARM or transponder based. The trouble is that at the moment there isn't. To ban gliders from cloud is difficult to do unless it widely impacts the sport. Yes it's true that few fly in true IMC, but as I asked earlier, how do you legally define between IMC and cloud flying? Also there are times when a glider may have intended to remain clear but has had to fly through cloud to descend (wave flying?).
It's years since I flew gliders, but I did occasionally cloud fly. I also once climbed up the sunny side of cumulous to a few hundred feet above its base whilst staying out of it. It was fairly near a gliding site, so perhaps I was relatively safe, but having seen SEP's fly straight over glider sites at circuit height ... who knows?
I suppose the only sensible way in the meantime is for any glider flying through or in cloud to be in contact with ATC. That way, at lest any IMC aircraft can be warned. In the original scenario, I don't know the answers, but it certainly shows up the failings of flying IMC outside of CAS.
I know flying is expensive, but it shouldn't have to be priced to a point that excludes all but the very rich. I know the aurgument for reducing chances of a middair is complelling. I for one, would not relish the idea of being killed that way, but you still have to weigh up the odds. I think overhead joins present a far far higher risk, but nobody is jumping up and down about them! I'd hate to see all but the richest glider pilots banned from entering cloud. Maybe it will come, but be careful what freedoms you cry out to ban, one of these days it might be one of yours? Old argument I know, but where do you end with the idea of banning all that is not 100% safe?
SS
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Shortstripper
Firstly I dont have anything against gliders and stress I brought this up as a discussion point only.
You brought up a sensible point which is that gliders while flying in IMC should be in contact with the ATC unit that would be used by the majority flying IMC in that area. They can then listen out for positions of IMC aircraft and make regular position and level block reports.
Using glider frequencies is not going to help us as its likely we will be busy on the ATC unit covering that area and cannot be locked onto a glider frequency. Communication is vital for seperation but we must all be communicating. Maybe a rule stating that all gliders operating at 4000 feet and above should change from the glider frequency might help.
Picas above 4000 feet would also be of use. Other than flying under CAS its not hard for powered IMC aircraft to fly above 4000 and cruise above the majority of gliders. In my case i was coming down from FL100 but even in this case I held 6000 feet till clear of the gliding site. At some point even we have to come down but shoul know of other aircraft in IMC in that descent.
Pace
Firstly I dont have anything against gliders and stress I brought this up as a discussion point only.
You brought up a sensible point which is that gliders while flying in IMC should be in contact with the ATC unit that would be used by the majority flying IMC in that area. They can then listen out for positions of IMC aircraft and make regular position and level block reports.
Using glider frequencies is not going to help us as its likely we will be busy on the ATC unit covering that area and cannot be locked onto a glider frequency. Communication is vital for seperation but we must all be communicating. Maybe a rule stating that all gliders operating at 4000 feet and above should change from the glider frequency might help.
Picas above 4000 feet would also be of use. Other than flying under CAS its not hard for powered IMC aircraft to fly above 4000 and cruise above the majority of gliders. In my case i was coming down from FL100 but even in this case I held 6000 feet till clear of the gliding site. At some point even we have to come down but shoul know of other aircraft in IMC in that descent.
Pace
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Radio reportage of glider positions and block heights would be about as user friendly as the current NOTAM system - i:e lots of effort in for not much sense out.
In real IMC (or VMC for that matter) the best presentation of conflicting traffic is on a TCAS screen. We can instantly see the position (and preferably level) of any conflicting traffic with minimal distraction.
As Pace stated there is way too much other stuff going on for us to have the chart out looking for crinkly bottom farmstrip or some other obscure VRP.
Remember that if we are flying powered aircraft in IMC we are probably going somewhere and thus we are probably in completely unfamiliar airspace and the local VRPs mean very little to us without a lot of time consuming map reading.
Shortstripper - the financial arguments do not cut any sway. If you can afford to fly you can afford a transponder.
I am not asking you to fit TCAS (which is an expensive item, but one which I place at a far lesser value than that of my own life), just a plain old mode C transponder.
Please fit a transponder (preferably mode C as a minimum) if you plan to be in the clouds - it keeps us all safer.
SB
In real IMC (or VMC for that matter) the best presentation of conflicting traffic is on a TCAS screen. We can instantly see the position (and preferably level) of any conflicting traffic with minimal distraction.
As Pace stated there is way too much other stuff going on for us to have the chart out looking for crinkly bottom farmstrip or some other obscure VRP.
Remember that if we are flying powered aircraft in IMC we are probably going somewhere and thus we are probably in completely unfamiliar airspace and the local VRPs mean very little to us without a lot of time consuming map reading.
Shortstripper - the financial arguments do not cut any sway. If you can afford to fly you can afford a transponder.
I am not asking you to fit TCAS (which is an expensive item, but one which I place at a far lesser value than that of my own life), just a plain old mode C transponder.
Please fit a transponder (preferably mode C as a minimum) if you plan to be in the clouds - it keeps us all safer.
SB
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As will have been apparent I am with Scooter Boy.
Not only do you paint a dreadful primary radar target, you congregate in groups presenting a far greater risk of collision, you do not obey the normal rules for flying in cloud, and your pilots are not rated to be there in the first place (in the conventional sense). On top of all that you want to be made a special case, and you think I am being unreasonable.
Not only do you paint a dreadful primary radar target, you congregate in groups presenting a far greater risk of collision, you do not obey the normal rules for flying in cloud, and your pilots are not rated to be there in the first place (in the conventional sense). On top of all that you want to be made a special case, and you think I am being unreasonable.
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I love the "you" bit. Many on here are both power AND glider pilots 
I'm a current PPL, have done the IMC, and have decided to go back to gliding after a 20 year break. I can see both sides of the argument. However, glider pilots don't want to be made a special case ... they already are!
Come up with a good system (that will fit, has low consumption, doesn't fry balls or cost more than the a/c itself) and I'm sure we'd all happily fit one. In the meantime we can do is use radio, ATC and try to be as conspicuous as practical.
I'm sure you, Pace, SB ect, will, from now on be jumping up and down and doing everything you can to bring the terribly "dangerous" gliding fraternity into line with your idea of what constitutes "safe", or is it controlled? "We" or rather "they" can at present fly in cloud without an IMC or IR rating and have done for a long long time (certainly since before you or I took to the skies). You see no way to compromise, simply repeat what you've already said, and so to be honest are getting quite boring!
SS
I'm a current PPL, have done the IMC, and have decided to go back to gliding after a 20 year break. I can see both sides of the argument. However, glider pilots don't want to be made a special case ... they already are!
Come up with a good system (that will fit, has low consumption, doesn't fry balls or cost more than the a/c itself) and I'm sure we'd all happily fit one. In the meantime we can do is use radio, ATC and try to be as conspicuous as practical.
I'm sure you, Pace, SB ect, will, from now on be jumping up and down and doing everything you can to bring the terribly "dangerous" gliding fraternity into line with your idea of what constitutes "safe", or is it controlled? "We" or rather "they" can at present fly in cloud without an IMC or IR rating and have done for a long long time (certainly since before you or I took to the skies). You see no way to compromise, simply repeat what you've already said, and so to be honest are getting quite boring!
SS
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Shortstripper
I too have flown power and glider and enjoyed both
I don't however want to die just because somebody wants to fly IMC in cloud without a transponder.
So - for the very small minority of glider pilots who fly in cloud (not bothered about those who are close to the cloud base ), why not just say stay out or get a transponder.
I know that you can get decent lift without entering cloud.
I too have flown power and glider and enjoyed both
I don't however want to die just because somebody wants to fly IMC in cloud without a transponder.
So - for the very small minority of glider pilots who fly in cloud (not bothered about those who are close to the cloud base ), why not just say stay out or get a transponder.
I know that you can get decent lift without entering cloud.
I know that you can get decent lift without entering cloud.
When EASA make it prctical to fit a transponder without trebling the cost of the basic unit, I might start investigating how to fit one legally although there is no panel space to fit it, and insufficient power to run it.
Meanwhile, I propose to carry on occasionally climbing in isolated Cu, advertising my presence on 130.4 and hoping that IFR pilots who can comfortably make a minor diversion from track will be sensible (as I see it).
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You refering to intentional or unintentional cloud flying? With the best will in the world we can all suddenly find the gaps closing up, especially when wave flying.
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Shortstripper
I am sorry to bore you.
However, there are times for not compromising.
Those few gliders that fly in cloud are asking the rest of us to cross our fingers and hope when it comes to meeting a glider in cloud, while the rest of us take measures to avoid collision.
We may not like it any more than you, but transponders are the only game in town that is common to the vast majority of those that fly in cloud. Unfortunately the system only works as long as we all agree on the same one.
You know I cant come up with a better system, any more than you - other than the one we have. Defending your position on that basis is not convincing. You could however mandate the fitting of transponders. There are some very small transponders available and I am sure the issues of powering them could be solved - if there was a will to do so.
Indeed you have always had these priviliges, but so have the MPs always had their expenses. It is a dangerous game to rely on precedent when everyone else is playing the game by a different set of rules.
Oh, and it is not a matter of them and us - in fact quite the reverse, we all share the same sky, I love to see gliders up, but I really dont want to find one inside a cloud.
I really wish I could come up with something better - but equally I really hope it does not take a collision in IMC to change the rules because I reckon my guess is pretty good about the way the rules would change - and I dont think you will like the outcome.
I am sorry to bore you.
However, there are times for not compromising.
Those few gliders that fly in cloud are asking the rest of us to cross our fingers and hope when it comes to meeting a glider in cloud, while the rest of us take measures to avoid collision.
We may not like it any more than you, but transponders are the only game in town that is common to the vast majority of those that fly in cloud. Unfortunately the system only works as long as we all agree on the same one.
You know I cant come up with a better system, any more than you - other than the one we have. Defending your position on that basis is not convincing. You could however mandate the fitting of transponders. There are some very small transponders available and I am sure the issues of powering them could be solved - if there was a will to do so.
Indeed you have always had these priviliges, but so have the MPs always had their expenses. It is a dangerous game to rely on precedent when everyone else is playing the game by a different set of rules.
Oh, and it is not a matter of them and us - in fact quite the reverse, we all share the same sky, I love to see gliders up, but I really dont want to find one inside a cloud.
I really wish I could come up with something better - but equally I really hope it does not take a collision in IMC to change the rules because I reckon my guess is pretty good about the way the rules would change - and I dont think you will like the outcome.
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Where has it been solved and how? What was the effect on gliding, GA, helicopters, microlights and so on?
A. For IFR flight in Class G airspace above the higher of 5,000 ft MSL/3,000 ft AGL, as well as within a TIA/TIZ or above a TIA, a flight plan must be submitted and two-way communication with ATC will be required. This allows ATC to provide information to other IFR traffic about areas where IFR soaring is taking place, allowing that traffic to avoid those areas. Transponder is not required.
B. IFR flight in Class C airspace, including in the CTA (i.e., everywhere above FL95), can be done without transponder in designated areas. This is handled by direct, local communication between the local soaring community and the terminal and area control centers. Gliders are given certain agreed sectors where they can fly IFR without transponder, and other IFR traffic is routed around those areas. The sectors are located so they are away from the commonly used IFR routes (SID/STAR etc), and conveniently placed for gliders (in close proximity to the prime gliding airfields).
C. Large areas of restricted airspace is set aside for soaring in clouds. Other traffic is only given permission to pass through those areas in VMC.
D. "Contact IMC" (i.e., IMC with the ground in sight, meaning climbing up to the cloud base) is allowed in Class G airspace up to FL95, and also within designated areas of TMA/CTR. This is a weakness; descending out of a cloud, you could come across a glider 10 ft below the cloud base. Not a problem for CAT though, as their approaches always take place in controlled airspace.
What this means in practice is that gliders have very good opportunities for contact IMC and IFR flying, whereas powered IFR aircraft know what areas are free of IFR gliders and can choose to avoid contaminated areas. It also means IFR and IMC gliders can not go wherever they want (unless they fit a transponder, in which case they just follow the normal rules), while powered aircraft might have to take a sometimes lengthy detour if they want to avoid the gliding areas. It also offers no protection in Class G airspace below 5,000 ft, which might be problematic for the helicopters?
Incidentally, this works very well for VFR as well. Cloud base permitting, I always choose to climb into the TMA wherever therre is one, in order to get information on sectors where soaring is taking place.
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There is no way the Swedish system would be implemented any time soon in the UK.
Some reasons:
1.The UK has a totally different ATM system, there are often more then one unit responsible for one pice of airspace. (Unlike Sweden) It´s funded at a pice-by-pice basis, not like LFV in Sweden that can fund everything from one big budget.
2. It´s doubtful if the soaring community would get the same airspace access today in Sweden, given that Thomas Allard head of ATM in LFV is even worse then NATS with regards to "you play, you pay".
3. Sweden has HUGE expanses of airspace between the east coast and the border with Norway. Allmost no TFC IFR below say FL250. Even a Swedish ATCO I went to college with once called it "a desert". It´s very quiet even by Norwegian standards.
4. I hazard to guess that 95% of all powered aircraft in Sweden have a Mode C/S transponder, easy to accomodate in the busy-ish airspace on the east coast and Göteborg/Skåne.
For someone working or flying in a integrated airspace structure like Norway/Sweden/Finland, it´s hard to appreciate the rather fragmented UK system.
M609
.....with an old swedish ATCO license somewhere....
Some reasons:
1.The UK has a totally different ATM system, there are often more then one unit responsible for one pice of airspace. (Unlike Sweden) It´s funded at a pice-by-pice basis, not like LFV in Sweden that can fund everything from one big budget.
2. It´s doubtful if the soaring community would get the same airspace access today in Sweden, given that Thomas Allard head of ATM in LFV is even worse then NATS with regards to "you play, you pay".
3. Sweden has HUGE expanses of airspace between the east coast and the border with Norway. Allmost no TFC IFR below say FL250. Even a Swedish ATCO I went to college with once called it "a desert". It´s very quiet even by Norwegian standards.
4. I hazard to guess that 95% of all powered aircraft in Sweden have a Mode C/S transponder, easy to accomodate in the busy-ish airspace on the east coast and Göteborg/Skåne.
For someone working or flying in a integrated airspace structure like Norway/Sweden/Finland, it´s hard to appreciate the rather fragmented UK system.
M609
.....with an old swedish ATCO license somewhere....
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There are a few things a bit odd about your report, Pace. I am not saying you are making anything up, but it is strange that:
1) You filed IFR for a flight to the North West at FL 100. You should have filed at FL105 or FL085. This would have significantly reduced the risk of your hitting another aircraft.
2) You state that you were "on top". In that case you were probably VMC, and during that phase of flight you should have been keeping a sharp eye out as per any VFR or uncontrolled flight. If you had, there wasn't much risk of collision in this phase.
3) If you were passing close to Brize and Shawbury, and were heading north-west you could have asked to join CA near Liverpool and undertaken your descent in CA, as presumably you were not that far from the Manchester Control Area? It might have required you to fly 15-20 miles further to achieve this, but at least you would have been safe in descent.
4) I don't think you could have been "dumped" by Air Traffic if you had effectively asked for a direct track to your destination. You presumably came out of CA east of Brize, which would be just about where you should have expected to have left CA. If you have an IR, why didn't you stay inside CA (as another responder has suggested?) If you don't have an IR, I suggest you get one if you are going to be flying inside CA, especially if it is Class A!
Was the twin over 2000kg AUW? If so, you would have paid en route (IRC) charges for the flight. If it was 2000kg or less, you would not be paying IRC, and in those circumstances, I don't think you can grumble about there not being any radar available to you in uncontrolled airspace, as the provision of radar costs money!
You state there was a glider at 6000 ft when there was also layers of cloud down to 2000 ft. It was windy. This would be quite an unusual occurrence as gliders don't normally operate between layers (not much lift between layers for a start), or above layered cloud, or in windy conditions.
So, your report does seem a bit flakey!
RB
1) You filed IFR for a flight to the North West at FL 100. You should have filed at FL105 or FL085. This would have significantly reduced the risk of your hitting another aircraft.
2) You state that you were "on top". In that case you were probably VMC, and during that phase of flight you should have been keeping a sharp eye out as per any VFR or uncontrolled flight. If you had, there wasn't much risk of collision in this phase.
3) If you were passing close to Brize and Shawbury, and were heading north-west you could have asked to join CA near Liverpool and undertaken your descent in CA, as presumably you were not that far from the Manchester Control Area? It might have required you to fly 15-20 miles further to achieve this, but at least you would have been safe in descent.
4) I don't think you could have been "dumped" by Air Traffic if you had effectively asked for a direct track to your destination. You presumably came out of CA east of Brize, which would be just about where you should have expected to have left CA. If you have an IR, why didn't you stay inside CA (as another responder has suggested?) If you don't have an IR, I suggest you get one if you are going to be flying inside CA, especially if it is Class A!
Was the twin over 2000kg AUW? If so, you would have paid en route (IRC) charges for the flight. If it was 2000kg or less, you would not be paying IRC, and in those circumstances, I don't think you can grumble about there not being any radar available to you in uncontrolled airspace, as the provision of radar costs money!
You state there was a glider at 6000 ft when there was also layers of cloud down to 2000 ft. It was windy. This would be quite an unusual occurrence as gliders don't normally operate between layers (not much lift between layers for a start), or above layered cloud, or in windy conditions.
So, your report does seem a bit flakey!
RB
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There are a few things a bit odd about your report, Pace. I am not saying you are making anything up, but it is strange that:
1) You filed IFR for a flight to the North West at FL 100. You should have filed at FL105 or FL085. This would have significantly reduced the risk of your hitting another aircraft.
1) You filed IFR for a flight to the North West at FL 100. You should have filed at FL105 or FL085. This would have significantly reduced the risk of your hitting another aircraft.
The report is factual the incident has been filed with my personal details and the flight details to the relevant authorities.
I notice you do not print your name and address here as it is an anonymous forum and neither do I. Anyone who wants further details can PM me and will be happy to respond when I know who I am talking to.
Frankly I resent your implications that I am some sort of liar I notice on your public profile here you are an ATP well so am I so PM me if you want a more detail.
Pace
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I don't think you can grumble about there not being any radar available to you in uncontrolled airspace, as the provision of radar costs money!
What we should do is sell off our share in NATS and exempt Avgas from duty to level up the playing fields with CAT (who pay no duty on fuel). What we should also do is open up more upper airspace to GA so they can burn a whole load less fuel. Then we can ask GA to pay for en route radar - which I suspect they will be more than happy to do - having rather a load of change left over I suspect.
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Just out of interest as someone who is relatively new to TCAS, how good is the system at resolving collision avoidance of something in a very tight orbit? Or indeed multiple contacts in a very tight orbit?
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TCAS works in the vertical plane only. Consequently it is more interested in whether the conflicting aircraft (ie in the TCAS equipped aircraft's flightpath) is climbing or descending.
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How would that work in a TCAS equipped glider given that they're climbing one moment, descending the next and rarely maintain anything constant for more than a second or so?
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Traffic Collision Avoidance System - Wikipedia, the free encyclopedia
Gives a pretty good description of TICAS and how it works
Pace
Gives a pretty good description of TICAS and how it works
Pace
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On a point of order you will find very few GA aircraft fitted with TCAS - but far more fitted with TAS.
TAS displays the target relative to you and its climb or descend trend but does not provide a RA.
I have no idea the relevance of the earlier comment that TCAS only works in the vertical plane, unless this is a reference to RAs.
Skyforce is probably the most common system in GA used by both Avidyne and Garmin in their glass cockpits.
Skyforce tracks up to 50 targets at any one time so is more than capable of providing enough information to avoid a group of gliders - if only they were transponding!
If you are interested in hearing more about the system this is a useful introduction: TAS600 Series Demonstration
I suspect the long term future is ADS-B, and I suspect gliders will eventually be required to carry ADS-B regardless - and not before time. How long it takes EASA to committ to ADS-B remains to be seen given their infatuation with mode S. Skyforce is already able to track both ADS-B and mode S/C targets.
For all those operators who complain about the weight have a look at something like the Trig
http://www.trig-avionics.com/library/tt31brochure.pdf
the whole units weighs in at 3lb, just a little more than a bag of sugar. I suppose most of us could lose that amount from around our waist if we wanted too.
The unit uses between 0,2A and 0.4A hardly a massive power consumption.
As importantly the unit supports ADS-B should that come to pass.
Of course there is also the T21 - but I guess either the cost (£1,500), the weight 500g, the size, a pack of cards is still too much for some.
TRIG Avionics has introduced a new lightweight Mode S transponder. The TT21 transponder system meets all the Mode S transponder requirements but weighs less than 500 grams.
With an ultra-compact front panel controller and a small transponder block the new TT21 will squeeze into any aircraft. Ideal for light sport and microlight aircraft, as well as conventional light aircraft where there is not much panel space, the TT21 low power design means that it can also run on batteries for gliders and balloons.
The TT21 is a two part system – the front panel controller features an LCD display and conventional controls, and incorporates an altitude encoder, whilst the remote transponder box contains the power supply and the receiver/transmitter. The rear box is not much larger than a pack of cards, and can be mounted anywhere convenient in the aircraft.
Despite the small size the TT21 nominal power output for reply pulses is 130 Watts, and it even supports ADS-B out using 1090MHz extended squitters, which means that it offers a path to future ADS-B based surveillance.
The TT21 will initially be certified in Europe and the USA. The TT21 will be available in February 2009, and is expected to retail for around £1,295 / €1,620 (plus taxes).
TAS displays the target relative to you and its climb or descend trend but does not provide a RA.
I have no idea the relevance of the earlier comment that TCAS only works in the vertical plane, unless this is a reference to RAs.
Skyforce is probably the most common system in GA used by both Avidyne and Garmin in their glass cockpits.
Skyforce tracks up to 50 targets at any one time so is more than capable of providing enough information to avoid a group of gliders - if only they were transponding!
If you are interested in hearing more about the system this is a useful introduction: TAS600 Series Demonstration
I suspect the long term future is ADS-B, and I suspect gliders will eventually be required to carry ADS-B regardless - and not before time. How long it takes EASA to committ to ADS-B remains to be seen given their infatuation with mode S. Skyforce is already able to track both ADS-B and mode S/C targets.
For all those operators who complain about the weight have a look at something like the Trig
http://www.trig-avionics.com/library/tt31brochure.pdf
the whole units weighs in at 3lb, just a little more than a bag of sugar. I suppose most of us could lose that amount from around our waist if we wanted too.
The unit uses between 0,2A and 0.4A hardly a massive power consumption.
As importantly the unit supports ADS-B should that come to pass.
Of course there is also the T21 - but I guess either the cost (£1,500), the weight 500g, the size, a pack of cards is still too much for some.
TRIG Avionics has introduced a new lightweight Mode S transponder. The TT21 transponder system meets all the Mode S transponder requirements but weighs less than 500 grams.
With an ultra-compact front panel controller and a small transponder block the new TT21 will squeeze into any aircraft. Ideal for light sport and microlight aircraft, as well as conventional light aircraft where there is not much panel space, the TT21 low power design means that it can also run on batteries for gliders and balloons.
The TT21 is a two part system – the front panel controller features an LCD display and conventional controls, and incorporates an altitude encoder, whilst the remote transponder box contains the power supply and the receiver/transmitter. The rear box is not much larger than a pack of cards, and can be mounted anywhere convenient in the aircraft.
Despite the small size the TT21 nominal power output for reply pulses is 130 Watts, and it even supports ADS-B out using 1090MHz extended squitters, which means that it offers a path to future ADS-B based surveillance.
The TT21 will initially be certified in Europe and the USA. The TT21 will be available in February 2009, and is expected to retail for around £1,295 / €1,620 (plus taxes).
Last edited by Fuji Abound; 5th Jun 2009 at 07:42.