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Your Thoughts on UAT vs ES ADSB

DennisRhodes

Well Known Member
I've been rather surprised on both the market response and the availability of UAT ADSB equipment. Both seem to be rather low. All the Ads are for the high $$$$ ES equipment with total replacement of transponders along with the latest display of Wx and Traffic. I never fly higher than FL180!!! ,rarely ever get over 10,000 and can never recall being outside the USA boundaries. Is there just that much market for the Higher end ES in this sector of GA? The price for UAT is less than ES ( but not that much), but could be, with a better market and a few more customers. Aside from the small hand full of suppliers of UAT equipment, do you thing that is just result of where the market is being driven? We all continue to complain about the High cost of ADSB compliance equipment but we are only choosing the most expensive products. Check the used market price of the Garmin 327 transponder which you would think be great for UAT service but instead there seems to be a failing market for those. You can get one off VAF for $350. Your thoughts?
 
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I think the price difference between UAT and ES technology is too close for many who are Planning on replacing their 20 year old KT76 anyway.

It's probably to soon settle the "VHS/Betamax" argument anyway. We'll see what Santa brings us in 2019.
 
UAT is only recognized

in the US. Everyone else on the planet has adopted 1090 ES as THE solution. Personally, I could 'get by' with UAT, but there is always the possibility that I might want to go somewhere that requires ES. Cost is already down pretty well, at least in 'aviation monetary units', sort of where we were when the mode C transponder was mandated. UAT is starting off as a worldwide orphan, and will not get a wider audience... ever.
 
Initially I hoped to get $1K for my 327. Then $850 seemed more realistic. By the time I actually was ready to sell it was $600. Now less. At prices like these can Garmin be selling ANY new ones?
I suspect a lot of pilots are like me: already owned a TSO'd gps source (G420W); already owned an ADSB-in that I liked (SkyRadar D2). With selling the 327 plus the FAA rebate my cost for adding a TT22 mode SES transponder (remote mounted, controlled thru the GRT HX) was down to $1100. And no new antennas, no new coax runs needed. Was hard to see how a UAT would be cheaper, once you add in antennas, coax, etc. Plus, maybe someday the wx will be horrible enroute but will top out at 18000, and I'll want to cruise in the flight levels. Or go to Bermuda (or maybe Mexico). Who knows what they'll require but it almost certainly will not be UAT. Plus a UAT antenna would have slowed me down 1/2 knot. -:)
 
There are pros and cons to both:

UAT Pros:
- anonymous mode
- cheaper in general if NavWorx starts producing again

UAT Cons:
- no flightradar24 tracking
- no 18k+'
- no international

ES Pros:
- may replace old transponder in the process
- flight tracking via flightradar24
- easier installation (in my experience)

ES Cons:
- possibly more expensive in general, although in some situations not much
- no anonymous mode

There are more, but that is the summary from where I stand.
 
Two reasons to go 1090 Mode S/ES:
1) if other nations mandate ADSB, it will almost certainly be 1090 as this is the standard already adopted by other countries (think of flying to Canada, Mexico or the Bahamas)

2) From a Search and Rescue perspective, the Aireon satellites are committed to being able to monitor, track, and report last known track and position of 1090 S/ES ADSB-equipped aircraft, and to provide that information to Search and Rescue coordinators when requested. This is a satellite-based ADSB monitoring capability riding on Iridium satellites, designed to be able to provide ADSB capabilities around the world. While we currently see the USA using ground-based ADSB, other nations, particularly those with responsibility for oceanic ATC, see satellite-based ADSB as the only means by which to move forward. This makes 1090 S/ES the only viable option from and ADSB-OUT perspective.
 
1090ES

I agree with Canadian Joy....
At some point in the future the FAA will decide that UAT is obsolete & not supportable.
Aapareo Stratus 1090ES ESG or ESGi Out & In--via Foreflight to I-Pad is definitely worth looking into and the best value for your money. I checked with Aircraft Spruce & they will build your harness for the ESG or ESGi.
 
I agree with Canadian Joy....
At some point in the future the FAA will decide that UAT is obsolete & not supportable.
i.

I'm not so sure. Remember the whole reason we have this two-frequency system is that the FAA was afraid that if everyone was on 1090 MHz there would be problems with frequency congestion.
 
Satellites and belly antenna?

Two reasons to go 1090 Mode S/ES:
1) if other nations mandate ADSB, it will almost certainly be 1090 as this is the standard already adopted by other countries (think of flying to Canada, Mexico or the Bahamas)

2) From a Search and Rescue perspective, the Aireon satellites are committed to being able to monitor, track, and report last known track and position of 1090 S/ES ADSB-equipped aircraft, and to provide that information to Search and Rescue coordinators when requested. This is a satellite-based ADSB monitoring capability riding on Iridium satellites, designed to be able to provide ADSB capabilities around the world. While we currently see the USA using ground-based ADSB, other nations, particularly those with responsibility for oceanic ATC, see satellite-based ADSB as the only means by which to move forward. This makes 1090 S/ES the only viable option from and ADSB-OUT perspective.

Question:

Does the satellite tracking work with our small planes that only have a transponder antenna on the belly?

The full ADBS system for the larger planes use a second transponder antenna on the upper surface for satellite communication.
 
The short answer is that satellite monitoring is capable of picking up belly-mount antenna signals. It's sub-optimal, but it does function.
 
Jesse,

That's a very objective comparison. Honest analysis. Each system has it's pros and cons.

I might add to UAT Pros:

If you already have a GTX 327/32 Mode C transponder then the 2020 UAT box can be installed and interfaced without loosing the value of the existing transponder on the flat used market and the static system need not necessarily be touched.

And add to the 1090 cons:

Take the following for what it is from somebody who lives within eye shot of the border fence with Mexico and within the reduced civil right zone within 30 miles of our international boundary to the South. While being a huge supporter of law enforcement and the highest respect for our AMOC team in Riverside, CA who track threats to our society....

A. Right to travel within the boundaries of our country unfettered by government..... It's a right. Having to cross border patrol checkpoints on a weekly basis can sharpen one's interest in our civil rights. Even for a patriotic farm boy like me.

B. User fee ready. Perfect device for tracking and billing GA aircraft if user fees like ATC fees, landing fees come to fruition, which the privatization of ATC push by the current administration has some people thinking about.

C. Red light cameras. Clip the corner of airspace, inadvertently stray into a popup TFR, turn the wrong way on a taxiway and FAA software catches it instantly and a computer automatically generates a form letter mailed to the registered owner's address. Maybe even when formation flying without all wingmen squawking standby (the "standby" squawk of which is against the regulations when ADS-B equipped). This correspondence will be mailed probably without a real person at the FAA even being aware of it, initially. Kind of like the IRS does if you make a typo on a form (I have my "dumb farmer letter" ready in my top desk drawer at the ready for such things). I don't know of one pilot, no matter the experience and/or skill, set that hasn't learned from some mistake in their past and uses that event to make sure it never happens again. All on their own without having some bureaucrat giving them a lecture at the least, or a fine or revocation at the worst. This results in little more than revenue generation through fines and the affirmation of a government job with pension.

40% of the business in our shop is for aircraft based out of Mexico. Both X numbered and N numbered and we get to visit with these savvy customers on a weekly basis. They laugh at ADS-B and don't plan on an installation for international flying South any time they can forsee. They are quick to point out that the majority of Mexico doesn't even have radar coverage unless at flight level with continental radar. If you've ever done much flying in Mexico then you know even at large airports like Juarez when talking to ATC you have to give them a VOR radial and distance as they have to plot your location manually until the tower can see you visually. These Mexican customers say they don't see the adoption and implementation of an ADS-B mandate in Mexico in their lifetime.

Does anybody regularly fly their RV above 18,000 feet?

Normally I would say if you don't have 12" N Numbers the international point is mute anyway. But then again about 1/3 of those same Mexico-based airplanes regularly clear customs both ways with 3" registration numbers and they just give me blank stares when I ask them about it.

There is no question that Canada will likely adopt 1090ES ADS-B out. I recently attended a Garmin technical training class in Kansas City and sat next to a bright young lad from up North who does avionics installations in Twatters and business class jets and he told how Canada's initial idea was to only require ADS-B out in very limited areas including some of the Northwest Territories. Even then it will be only on IFR flight plans above a certain flight level. He surmised Mode C only will be around for quite some time for the balance of Canada. Very bright nice fellow. I have yet to meet a Canadian I didn't like.

In summary I am not bashing the idea of 1090ES ADS-B out. In fact I am putting GTX 345 in my Piper Comanche. There should really be no detectable difference between UAT and 1090ES on a day to day operational basis and a straight transponder swap out (with wiring etc) can be easier than adding a stand-alone UAT box. But as a rule UAT is more appealing to me for sport flying and coyote chasing at a lower compliance cost while maintaining a modicum of privacy with anonymous mode.

Jim

P.S. Every day I am sounding more and more like my late father. Laissez-faire my friends.

There are pros and cons to both:

UAT Pros:
- anonymous mode
- cheaper in general if NavWorx starts producing again

UAT Cons:
- no flightradar24 tracking
- no 18k+'
- no international

ES Pros:
- may replace old transponder in the process
- flight tracking via flightradar24
- easier installation (in my experience)

ES Cons:
- possibly more expensive in general, although in some situations not much
- no anonymous mode

There are more, but that is the summary from where I stand.
 
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I was an early adopter of ADSB and chose UAT because it was the only affordable option at the time.

The discussions about airspace legalities are all good to know.

I wanted to add my practical experience with UAT only.

First, it is not infallible. It is by design, dependant on ground station line of sight. At my home base of Asheville which is the busiest GA airport in North Carolina, I get ZERO traffic from FIS-B because AVL is not compliant yet. My friends with 1090ES IN can see me just fine. Some days on my commutes there is so little traffic showing in areas I DO get FIS-B that I am sure the system is lying to me. Just to confirm, my onboard system works. Some days there is a beehive.

I know there are some units that receive both UAT and 1090. IF I was to do over, that is what I would choose.
 
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Or better yet. Hard install a 2020 compliant "out only" on board the aircraft. Out (transmit) is the only direction needed for 2020 compliance. Then choose a separate nice inexpensive dual-band "in" receiver covering both 978 and 1090. I suggest a quality portable with a battery backup and attitude built in as an added feature. GDL-30 3D, Stratus, iLevel etc. Whatever suits your fancy this year. A dedicate external "in" antenna and coax that can be used with any of the full capability portable in units. Nobody says you have to have one permanent mounted box be both "in" and "out". The installed in and out combo units are very expensive and limit your options to certain software and hardware for weather and traffic. Fooey. Keeping the transmit and receive systems separate helps avoid buyers remorse by allowing any display or software one prefers all the while making it an easy and cheap change to a different in box as technology improves or one's tastes change.

Jim
 
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