ADS-B Changes for LSA and Experimental!

here's one trap - who is qualified to determine that the equipment meets the performance requirements of the TSO? Do we just accept the datasheet for the box?

This isn't quite like putting a non-certified glass panel or non-certified flight instrument in a single aircraft. ADS-B is a system of equipment in multiple aircraft and ground equipment. Bad data can impact multiple parties in the overall airspace system.

Of course, the possibility of bad data for a non-certified box/installation needs to be balanced against the certainty of no data if the aircraft owner choses not to install ADS-B at all.
 
here's one trap - who is qualified to determine that the equipment meets the performance requirements of the TSO? Do we just accept the datasheet for the box?

This isn't quite like putting a non-certified glass panel or non-certified flight instrument in a single aircraft. ADS-B is a system of equipment in multiple aircraft and ground equipment. Bad data can impact multiple parties in the overall airspace system.

Of course, the possibility of bad data for a non-certified box/installation needs to be balanced against the certainty of no data if the aircraft owner choses not to install ADS-B at all.

Do you typically get bad data from Mode C transponders in E-AB aircraft?

Why would ADS-B be any different?
 
They need to approve portable ADSB out devices for the smaller aircraft. There are such devices available with WAAS GPS receivers for $1500. Put that in a stratus 3 and I'd buy it.

Not only LSA and Exp aircraft, but what about "Restricted" Catagory, like our Pawnee glider tug.
 
It will be interesting to see how quickly new portable and non-TSO'ed panel mount devices appear. I suspect Garmin, Trig, Dynon, and others have their devices ready to go and were just waiting for the word that they'd be legal.
 
It will be interesting to see how quickly new portable and non-TSO'ed panel mount devices appear. I suspect Garmin, Trig, Dynon, and others have their devices ready to go and were just waiting for the word that they'd be legal.

+1 agree completely,the big boys,want all the money.
 
They need to approve portable ADSB out devices for the smaller aircraft. There are such devices available with WAAS GPS receivers for $1500. Put that in a stratus 3 and I'd buy it.

Not only LSA and Exp aircraft, but what about "Restricted" Catagory, like our Pawnee glider tug.
is it restricted ? mine is standard if the booms are off. I assume you don't have booms.
 
I'm ready for affordable solution for my experimental glider.
current I am invisible to just about everyone but other gliders (FLARM)

Brian
 
is it restricted ? mine is standard if the booms are off. I assume you don't have booms.

Restricted, glider and banner tow.
Technically you can't tow gliders (or banners) on a restricted agricultural certificate.
 
It will be interesting to see how quickly new portable and non-TSO'ed panel mount devices appear. I suspect Garmin, Trig, Dynon, and others have their devices ready to go and were just waiting for the word that they'd be legal.

And the rest of us are still under the Certificated rules.

bah humbug. 2019 will probably sell the cherokee and return to sailing.
 
I've been working on a Field Approval to add ADSB-Out to my motor glider. The FA will be based on a STC using the Trigg Mode S transponder and the FreeFlight GPS. I will be using the Dynon variant of the Trigg transponder thus the following discussion over on the Dynon forum-

http://dynonavionics.com/cgi-bin/yabb2/YaBB.pl?num=1418963161/36#36

I believe the FAA is being very careful to make sure ADSB-Out installations function as a system (GPS antenna all the way through to transponder antenna). This would make sense given their experience with helicopters in the Gulf.
 
here's one trap - who is qualified to determine that the equipment meets the performance requirements of the TSO? Do we just accept the datasheet for the box?
So far, the answer appears to be "yes". The FAA is willing to accept less stringent verification for the non-TSO'd units. However, the manufacturers want specifics. for the "less stringent verification."

One advantage is that the ADS-B system apparently has a "self test" that *completely* checks out the unit. So the individual can verify that they installed it properly. Don't know if checks, etc. are going to be needed like a transponder. If they use the GPS altitude readout instead of an encoder, maybe not.

[Edit: Looks like they still use the encoders...see a few posts below]

They're trying to arrange lower-cost units, but the problem is, aircraft owners are under a barrel. They *have* to buy a box in the next five years... so the mfgs know they have a captive market.

Ron Wanttaja
 
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So far, the answer appears to be "yes". The FAA is willing to accept less stringent verification for the non-TSO'd units. However, the manufacturers want specifics. for the "less stringent verification."

One advantage is that the ADS-B system apparently has a "self test" that *completely* checks out the unit. So the individual can verify that they installed it properly. Don't know if checks, etc. are going to be needed like a transponder. If they use the GPS altitude readout instead of an encoder, maybe not.

They're trying to arrange lower-cost units, but the problem is, aircraft owners are under a barrel. They *have* to buy a box in the next five years... so the mfgs know they have a captive market.

Ron Wanttaja
Fortunately with this new ruling, more market forces can be brought to bear on both price and innovation. Unfortunately, certificated planes will pay a premium for the luxury of ... whatever it is that makes certificated aircraft better. :rolleyes:
 
We have to test and re certify transponders and encoders every 24 months...

Is that required for the ADS-B units???

Yes, its part of transponder. Also FAA can monitor validity in use and after implementation date will tell you if its hosed up, not ATC another compliance unit. Now you can request a report from them to get a status of your ADSB transmissions.
 
FAA wanted EAA off their backs, looks like. They know AOPA won't play. It'd hurt their biggest magazine advertisers more.
 
Yes, its part of transponder. Also FAA can monitor validity in use and after implembentation date will tell you if its hosed up, not ATC another compliance unit. Now you can request a report from them to get a status of your ADSB transmissions.
From what I gather, ADS-B is completely independent of the current transponder systems. The FAA justified the system, in part, because it will allow eliminating about half the radars. Wouldn't be the case if they expected to keep using transponders.

I've got a system block diagram for ADS-B, and it does show "Baro Altitude" as an input to the ADS-B equipment. So this would mean we'd still be carrying the altitude encoders and thus still have to do recerts.

Ron Wanttaja
 
Just to be clear, the FAA's transmission check just checks that you are transmitting messages with all the right content. The service does not-

(1) verify that system latency meets specification
(2) the system is transmitting accurate data (no check of transmitted position against observed position

Right now, the only way the FAA can affect overall system installation quality is to make the manufacture of the equipment and the person responsible for installation to test the system and submit data proving the overall installation is accurate. This is why the original requirement was for an STC. Of course, that level of proof was simply not practical if the FAA wanted much of anyone to install the equipment thus it was relaxed to STC or Field Approval based on an existing STC.

This is still a mess and is going nowhere anytime soon.
 
From what I gather, ADS-B is completely independent of the current transponder systems. The FAA justified the system, in part, because it will allow eliminating about half the radars. Wouldn't be the case if they expected to keep using transponders.

I've got a system block diagram for ADS-B, and it does show "Baro Altitude" as an input to the ADS-B equipment. So this would mean we'd still be carrying the altitude encoders and thus still have to do recerts.

Ron Wanttaja


Wouldn't the baro altitude input be for the GPS and not necessarily for the transponder?
 
GPS calculates it own altitude (though subject to the usual 10M accuracy limitations).

The baro altitude can be used as a check of the GPS calculated altitude.
 
I thought GPS horizontal resolution was about 10m, but altitude was lower accuracy due to satellite visibility issues...WAAS notwithstanding, I guess.
 
From what I gather, ADS-B is completely independent of the current transponder systems. The FAA justified the system, in part, because it will allow eliminating about half the radars. Wouldn't be the case if they expected to keep using transponders.

I've got a system block diagram for ADS-B, and it does show "Baro Altitude" as an input to the ADS-B equipment. So this would mean we'd still be carrying the altitude encoders and thus still have to do recerts.

Ron Wanttaja

Hi Ron!

I think you're batting 50% on the 'completely independent' thing. We're using the KT76A transponder we had prior to ADS-B without modification after installing a GDL88 ADS-B. The other technology is 1090 ES ADS-B out format, which uses an enhanced Mode S transponder. Two different ways to accomplish the same thing.

From memory when studying, I believe the GDL 88 ADS-B unit includes it's own encoder, also.

Jim
 
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From what I gather, ADS-B is completely independent of the current transponder systems. The FAA justified the system, in part, because it will allow eliminating about half the radars. Wouldn't be the case if they expected to keep using transponders.

I've got a system block diagram for ADS-B, and it does show "Baro Altitude" as an input to the ADS-B equipment. So this would mean we'd still be carrying the altitude encoders and thus still have to do recerts.

Ron Wanttaja

Mode-S extended squitter? What transmits AdSB in this config? Its What the high flyers use and some us low guys also. I dont see transponders going away, especially as radar backup in the terminal area.
 
Woot! My new panel, installed in 2014, appears to now be 100% ADS-B compliant, under this new interpretation.
:)
 
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