Transponders

[skyraft]

Will ADS-B out be required for experimental aircraft?

[cub builder]

Yes... ADS-B-Out will be required if you fly in:



Class A, B, and C airspace.
All airspace at and above 10,000 feet Mean Sea Level (MSL) over the 48 contiguous United States and the District of Columbia.
Within 30 nautical miles of airports listed in 14 CFR §91.225 (Class B), from the surface up to 10,000 feet MSL.
For Class E airspace over the Gulf of Mexico from the coastline of the United States out to 12 nautical miles, at and above 3,000 feet MSL.


By equipping with ADS-B out, you also get TIS-B (Traffic Information Service) which is also quite useful if you plan to travel in your Experimental Aircraft.

If you're building a low altitude puddle jumper and flying the local grass strips and small airports, then ADS-B-Out might very well be a waste of money for you.

As an example, I have it in my gofast travelling E-AB aircraft. But my SuperCub clone only has an ADS-B weather receiver that allows me to pick my way around the T'storms here in the summer. I rarely fly high enough in the SuperCub to mix with other aircraft outside of the traffic pattern, so for the most part, don't care about seeing traffic that's well above me.

-Cub Builder

[FlyingRon]

Essentially the rules are pretty much the same as the transponder rules. If you fly places requiring a transponder, you'll need ADS-B out.


By equipping with ADS-B out, you also get TIS-B (Traffic Information Service) which is also quite useful if you plan to travel in your Experimental Aircraft.

Only if you also equip the plane with some ADS-B in solution. What does travelling have to do with it. Most collision threats happen near the airport.

[cub builder]

Essentially the rules are pretty much the same as the transponder rules. If you fly places requiring a transponder, you'll need ADS-B out.


Only if you also equip the plane with some ADS-B in solution. What does traveling have to do with it. Most collision threats happen near the airport.

I mentioned a traveling plane to contrast the types of flying that might be done by the SkyRaft since he didn't mention the type of plane or where he plans to fly, and the E-AB world encompasses all types. While I'm sure there are lots of exceptions, most folks that travel a lot in their planes end up in airspace that will eventually require ADS-B-Out, while if you do nothing but low altitude rural puddle jumping, odds are that you won't need or even have much use for it. When I started flying with ADS-B Out and receiving traffic information, I was shocked at how much traffic is out there that I was blissfully unaware of flying around me. I've also been mildly surprised at how much traffic passes near me that I would have otherwise never known about. I love having it in the traveling plane. But for the puddle jumping I do in my Cub, having traffic displayed on the GPS wouldn't be very beneficial to me.

The difference is that in my SC, I'm rarely even at pattern altitude, so 1. there usually isn't any traffic at my altitude, and 2. ADS-B reliability is pretty poor at low altitudes in more rural areas for a variety of reasons, although a dual channel receiver will at least get the UAT and 1090-ES traffic. The single channel receivers will only see UAT-Out traffic.

As you said, mid airs usually happen within 5 miles of the airport. But when you're close in, it's time to get your head outside to watch for traffic. Also, when you're at low altitude in the traffic pattern in more rural areas, ADS-B becomes relatively useless as the mode-C traffic isn't seen by radar, and often times at or below 1000', you also lose the ADS-B stations, so you aren't receiving traffic. Of course if you're near a major metropolitan areas, it all works, but ADS-B out will be required there anyway.

-Cub Builder

[FlyingRon]

The whole point of ADS-B out is so that it works without the absolute reliance on ground based systems.

The best description of needing ADS-B is whether you could fly without a transponder today (with exception of the mode C veil requirements) the rules are the same.
You seem constantly confused over the requirements for ADS-B out (MANDATED) and what might be useful for ADS-B in (TIS and TAS).

[Al Burgemeister]

ADS-B Out can be provided by either UAT or 1090-ES. The former is a transceiver that can also provide TIS-B and FIS-B, as well as ADS-B In. The latter is provided by a properly-equipped Mode S transponder and only privides ADS-B In and Out. TIS-B and FIS-B are broadcasts provided by FAA only on the UAT frequency. FIS-B takes the radar and ADS-B Out positions from other aircraft (both UAT and 1090-B) and provides them to you. FIS-B provides local weather.

[cub builder]

The best description of needing ADS-B is whether you could fly without a transponder today (with exception of the mode C veil requirements) the rules are the same.
You seem constantly confused over the requirements for ADS-B out (MANDATED) and what might be useful for ADS-B in (TIS and TAS).

I'm not confused about it, but since I use both the In and Out, I do tend to reference them together which may indeed be confusing. Sorry if anyone is still confused about what is mandated, vs what is a useful flight information tool. But to be clear, ADS-B-OUT is the only requirement, and will be required in the airspaces listed above in post #2. If you plan to fly in those airspaces, Jan 1 of 2020, you will be required to have ADSB-OUT. You may provide that either by Mode-S transponder with 1090-ES or UAT Out (978 MHZ). Either will require a high accuracy WAAS GPS as a position source.

Any type of ADS-B IN is merely a nicety provided by the ADS-B system, and in many ways, is badly broken. Previous ramblings on my part about TIS-B and FIS-B has to do with the way I used them operationally and should not be construed as part of the mandate. However, the point that was apparently missed by FlyingRon and probably poorly made by me is that without ADSB-Out, you don't get Traffic Information Service (TIS-B) broadcast from the ADS-B ground station, so at best, you are getting an incomplete picture of the traffic.


The whole point of ADS-B out is so that it works without the absolute reliance on ground based systems.

Now that's funny! Some vendors (one is the leading vendor for E-AB aircraft) only sell single channel ADS-B receivers that use 1090-ES Out, but only receive UAT. They can't even see a like equipped aircraft without a ground based ADS-B tower to retransmit the data.

Actually, I do agree with you. In an ideal world with 100% implementation and dual channel receivers for those of us that want to see traffic displayed in the cockpit (NOT MANDATED), it could be an awesome tool. Unfortunately, the reality lies somewhere in between. It should work well in major metropolitan areas where ADS-B Out will be required, but with a number of vendors selling single channel receivers, those with single channel receivers optionally choosing to use the TIS-B data will be heavily dependent on ground based stations for complete TIS-B data. Outside of areas where ADSB-Out will be required, for the foreseeable future there will be a significant amount of traffic with Mode-C with no ADS-B out, which makes both radar and ADS-B ground stations a requirement to display the traffic (operationally this is pretty flaky). And there will always be the non-electric Cubs, Champs, Taylorcraft, etc that you will have to find with your eyes.

-Cub Builder

[FlyingRon]

It's not "funny." Just because you chose not to avail yourself of ADS-B in doesn't mean that others flying in the same airspace are as cavalier with their safety.

[Frank Giger]

With nothing but profound respect, Ron, I'd say you're overstating things a bit.

Not having ADS-B isn't being cavalier with with the pilot's or other aircraft's safety. We don't really have a huge problem with mid-airs as it is. ADS-B is another tool to reduce it even further, which is a good thing.

The mandates for where it's required make sense, too; it's a good thing in busy airspace with mixed types of aircraft. But that's not where a lot of pilots fly.

Personally, I fly in low traffic areas at around 1-3,000 feet AGL puttering along at 55 MPH (IAS). The Champ has a transponder that might as well have the knobs safety wired to 1200. My Nieuport has no transponder at all. Am I being cavalier with my safety? Not at all. I just don't fly in areas where it's needed or would put a big difference in the safety calculations.

[FlyingRon]

What makes you think a discrete code is necessary for traffic avoidance systems to work?

[Frank Giger]

I think we're typing past each other, which is most likely my fault.

I don't really have a dog in the ADS-B hunt, but I can think of a couple reasons for discrete codes.

First, it can assist by giving out type of aircraft and normal speeds. You know what makes me concerned? Both the airports I frequent occasionally get business jets, and they don't fly the pattern. They sometimes talk jibberish, giving their position by instrument check points (and some sound a bit miffed when I ask them to state their position to the airfield). I'm coming around base to final at 50 mph and they're screaming in at 150. I have a tiny plane, and they might not physically see me or understand that I'm gonna take some time to land and turn off at the first taxiway....and I get a business jet up my rear or landing on top of me.

Second, and most likely, is institutional inertia. Transponders have unique codes, so therefore ADS-B does, too. No thinking required, because it's Transponder Plus, and so it flows naturally.

[Mike M]

What makes you think a discrete code is necessary for traffic avoidance systems to work?

Nothing. Any more than I think a traffic avoidance system like ADSB would have prevented the over 13000 midair collisions in the USA that were reported in the latest data I could find, 2013.

[Marc Zeitlin]

Nothing. Any more than I think a traffic avoidance system like ADSB would have prevented the over 13000 midair collisions in the USA that were reported in the latest data I could find, 2013.Don't want to jump into the middle of whatever this discussion is about, but I have to ask - given that the 24th Nall report for 2012 indicates that there were a total of 6 mid-air collisions for GA aircraft that year (3 fatal and 3 non-fatal), and that even if we assume that level of mid-air collisions every year that airplanes have been flying, it would take 2,167 years to have 13,000 mid-air collisions. This seems somewhat unlikely, given when aircraft started flying and when more than two of them might have been in the air at the same time at the same place.

So unless you're including bird strikes as mid-air collisions, and unless you're counting some indeterminate # of years worth of them, I'd be interested to know where that 13,000 # came from...

Curious minds want to know.

[Mike M]

So unless you're including bird strikes as mid-air collisions, and unless you're counting some indeterminate # of years worth of them, I'd be interested to know where that 13,000 # came from...

Curious minds want to know.

I couldn't re-find the ref for the 13,000+ number, so I'll drop back to the number I was able to find this time. Over 11,000. My apologies for not saving the original ref.

Of course that includes bird strikes. They're midair collisions with the proven capacity to render the aircraft unairworthy. Not to imply that an AIRCRAFT traffic avoidance system isn't a noteworthy accomplishment. Just to remind that ADSB will do nothing to avoid the most prevalent collisions, nor to ameliorate the growing risk of collision with sUAV air vehicles which are not participating in ADSB technology.

FAA Wildlife Strike Report. Figure 1, the graph on page 66. 2013 bar.

[cub builder]

It's not "funny." Just because you chose not to avail yourself of ADS-B in doesn't mean that others flying in the same airspace are as cavalier with their safety.

OK. It's not funny. But it is a fact. Your statement about "it works without the absolute reliance on ground based systems" is incorrect. It is possible, if only we all lived in the FAA's ideal world. But that isn't reality.

I don't know why you would think I "choose" not to avail myself of that ADS-B data or am "cavalier" with my safety. In fact, I use a dual channel transceiver in the plane I use in busy airspaces and am highly critical of the vendors that are selling single channel receivers as the end all solution. That would be why I mentioned the issue with single channel receivers. Before buying an ADS-B unit or locking yourself into a vendor, one has to read very carefully to see what is not included.

-Cub Builder

[Helipilot]

Frank's post about 1-3,000 AGL makes me wonder about the MSL altitudes being used for ADS-B. If I take off at Gunnison, CO I'm already at 8,000+ MSL and I too usually poke around under 3K AGL. Therefore I am at 11k MSL, what are your opinions Guys?