Portable ADSB-Out...?

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Dana

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there’s NTSB data that already shows a drop in mid-air collisions precisely thanks to the ADSB.
Is that true? I hadn't heard that. Midairs are already so rare is there a valid statistical difference?
 

SpruceForest

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Doesn't change the fact that 24 month transponder check is legally required. Note that includes the static system so is aircraft-specific. I guess if you can get your avionics guy to check the system in both airplanes I guess it could be legal.

Finn
Different requirements...different paragraph... different inspections. 91.413 requires ANY installed transponder to be tested, and this may in reality be done on a bench for something like a cavity tube, non-ADS-B transponder (no data correlation requirements). 91.411 on the other hand requires only those aircraft operating under IFR in Class A-E conduct a biennial check of the static system, altimeter, and encoder. Folks often get both done at the same time, but while the static system, altimeter, and encoder check is optional based on the aircraft's usage (outside of other governing operating part), 91.413 is always required if a transponder is installed.

So to summarize:
- 91.913 requires ANY installed transponder on any airplane or helicopter, without regard to cert part (i.e., applies to non-TSO box on EAB as well as cert box in 23/25/27/29 aircraft) or where operated, be tested and inspected for compliance.
- 91.411 only applies to those aircraft operated IFR and in controlled airspace.

Your avionics guy should be able to clear up any details which are still a little fuzzy, such as the data correlation piece of 91.413.

Further, while you might be able to get permission for a non-ADS-B flight through ADS-B required airspace, a condition of that approval is an operative transponder, which is to say 91.413-compliant installed and operational transponder.
 
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SpruceForest

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Is that true? I hadn't heard that. Midairs are already so rare is there a valid statistical difference?
The studies performed by University of Alaska during/after Capstone Phases 1 & 2 effort did show a statistically significant reduction in both midairs and reported near-miss events, but let's keep in mind that Alaska aviation operations are often conducted over relatively narrow, terrain-constrained routes, during atrocious weather, and to/from lots of uncontrolled landing areas out in the back of beyond. When we did the initial benefits studies for Capstone, midair reduction was definitely a defined benefit, and the UAk folks saw evidence of that... but at the time, Alaska had far more than their share of midair events, so an easier job to suss out reduction from a larger pool of events. The FAA's Basis of Estimate for ADS-B claimed a benefit for reduced midair events, but I'm not sure anyone has since been able to demonstrate a statistically significant reduction in midair events in the Lower 48 that can be tied directly to ADS-B In (versus moving map, other tech or procedure change).
 
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Toobuilder

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Doesn't it say " certified with an engine driven electrical system ? If so, homebuilts are not certified.

My understanding of this context is that if the tail number (factory built or garage built) recieved its AWC "certification" with an engine driven electrical system installed, it can't be removed later and then meet the requirements of "no engine driven electrical system".

I think that if it had one when the "birth certificate" was issued, it forever has that stigma.
 

rv7charlie

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This sounds wrong. There’s no reason why the device cannot show every signal that’s in the range.
There are very real reasons why it won't, if you don't have 'out' in your own plane. Well documented 'whys', in both FAA advisory docs and many articles in the aviation press.

Lots of misconceptions have been posted in this thread. Proceed with caution, if you value your ticket.
 

rv7charlie

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Unless things have changed, you don't need a transponder when flying within the Mode C veil if you call the facility controlling the airspace in advance by telephone. They'll give you a code to mention to the controllers when you make radio contact.
It's not guaranteed everywhere all the time.
Things have indeed changed; you have to request through an FAA website within 24 hrs of accessing the airspace, and get approval.
 

SpruceForest

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I think they are certified ....a "special airworthiness certificate." is still "certified".....
not certified would be Part 103 .....no airworthiness certificate issued?....
Agree... three different FAA certificates defined in Part 21: type, production, and airworthiness (standard or special). I think we use 'uncertified' as 'inside baseball' shorthand for something without type cert, but running on a special airworthiness certificate. That said, everything except 107 (or operating under a LOE for UAS) has some sort of certificate in force when flown. 103 seems like a bit of a gray area to me, in that an inspection requirement may exist if the FAA asks or the owner asks the FAA for inspection, but other than that, it's paperless, so add that to the 'no cert/no way/no how' if you don't see self-cert as creating some sort of virtual paper ;-).

All that aside, I knew what Pops was talking about and - as usual - enjoyed reading it.
 
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Vigilant1

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For those interested, here's the FAA guidance on procedures for requesting authorization to operate within the Mode C veil without the standard equipment. It's a bit of a thicket, and procedures differ based on the requestor (govt or civil), equipment (just no ADSB-out, or also no transponder?).
I think this is the web site referred to by Charlie in Post 29:Service Availability Prediction Tool (SAPT) — Warning Page
The FAA says:
Operators requesting preflight ATC authorization to deviate from ADS-B Out equipage requirements for single or infrequent events should be referred to the FAA's automated authorization request web portal at https://sapt.faa.gov.
But, best to read the guidance before just diving into that web page.
 

bryancobb

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Be aware everyone...the FAA requirement for ADS-B Out in some airspace is not to be viewed as a nifty gadget to serve YOUR needs and wants. It is a very serious system for accurately tracking both "participating" (IFR) and "non-participating" (VFR) aircraft by ATC that is much better than radar. It replaces radar and instead uses a satellite network.

If you choose to enter airspace where it's mandatory, your installed system MUST serve the FAA's intended purposes and in order to do that, it must be installed exactly according to FAR's and manufacturer's guidance. Your ADS-B Out device is married and configured to a SINGLE AIRCRAFT and must be function-tested, in the air, in radar-controlled airspace, and that "box" must be faithfully attached to that aircraft and reporting accurately to the FAA anytime it leaves the ground. If you have a CUB with ADS-B Out, and move the box to your Citation and takeoff, you are sending fraudulent/flawed information to ATC and since they see a Cub on the scope going 350kts, the whole ATC system is a mess. Moral: Do it exactly right or don't do it at all. Stay out of controlled airspace unless you are using ADS-B Out as intended.

Swapping an ADS-B device from one aircraft to another is breaking the law, just like having two cars and swapping a tag from one to the other.
 

Toobuilder

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Well, swapping devices from one airframe to another is not "breaking the law" if you jump through the setup, testing, certification and reporting requirements with the swap - but those hoops are simply not worth it to be practical. I'll buy the handfull of relatively inexpensive shipsets before I'm going to try swap hardware from ship to ship. The "why is it structured this way" ship has sailed. We are where we are.
 

Pops

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91.215 says U.S.-registered civil aircraft. 91.215 says “originally certificated“ and ” not subsequently certified”with an electrical syst
What I am getting to is this. I had my JMR inspected by the FAA and and was" originally certificated" with a Special Airworthiness Certificated
with no engine driven electrical system. If I install a engine driven electrical system, do I need a Transponder since the "originally Certificated" was without an engine driven electrical system. Not your opinion, using the FAR's.
 
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bryancobb

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91.215 says U.S.-registered civil aircraft. 91.215 says “originally certificated“ and ” not subsequently certified”with an electrical system.
Legally flying into controlled airspace requires an ATC REPORTING SYSTEM or some other "prior approval" method that provides controllers adequate position/heading/airspeed/altitude on you, to insure safe separation. The FAA cannot allow an aircraft without an electrical system to create an unsafe situation.

It's clear, even though 91.215 wording was decided on many decades before ADS-B was imagined, that the "performance and environmental" conditions of whatever method a pilot uses as their authority to operate in controlled airspace, must meet FAA's needs pertaining to separation/safety.
 

Wanttaja

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... there’s NTSB data that already shows a drop in mid-air collisions precisely thanks to the ADSB.

Is that true? I hadn't heard that. Midairs are already so rare is there a valid statistical difference?
Old joke about a guy looking for an accountant. "How much is two plus two?" he asks the first guy, who responds, "Four." Asks the second guy the same question, who gives the same answer.

Third guy shows up. "How much is two plus two?" The accountant gets up, closes the door and window, and whispers, "How much would you like it to be?"

Can do pretty much the same trick for aircraft accident statistics.

In 2015, 1.6% of all US aircraft accidents were midairs. In 2019, after the implementation of the ADS-B mandate, the percentage was 1.0%

Yay! Yay?

But like Dana mentions, midairs are rare enough that the statistics can vary widely between years. Not only that, but the statistics count the NUMBER of aircraft involved in midairs. So the actual rate of occurrence of midair collisions as an event is a bit less than half the total.

("A bit less than half"? 2010 saw an ODD number of midairs. A Cirrus hit a glider towplane, thus involving three airplanes).

Plus... we cannot forget that the total number of accidents have decreased over the same period. Fewer midairs, yes, but the total count is down, too.

Instead, let's look a chart that combines the yearly number of aircraft involved in midairs with the total number of accidents. Midairs are tallied based on the left vertical axis, total accidents on the right.
midair comparison to overall accidents.JPG
So since 2008, midairs are trending downward...at about the same rate as overall accidents. So no, I'm not seeing any major effect of the ADS-B mandate. So don't go installing curtains in your aircraft windows.
bonanza curtains.jpg

Ron "Dern* liars, and" Wanttaja

* Curse that obscenity auto-correct! :)
 
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bryancobb

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Doesn't change the fact that 24 month transponder check is legally required. Note that includes the static system so is aircraft-specific. I guess if you can get your avionics guy to check the system in both airplanes I guess it could be legal.

Finn
On an experimental aircraft, or even on most light, certificated aircraft, a transponder is not required, period, regardless of whether or not the aircraft has an electrical system or when an electrical system was put in. In short, the FAA intends and allows simple, minimally-equipped aircraft to fly in the national airspace system. The next qualification is...does the owner CHOOSE TO HAVE A TRANSPONDER. If so, every aspect and rule of installation and operation must comply with FAR's. The third qualifier comes IF THE PILOT CHOOSES TO fly in any airspace where a transponder is REQUIRED (in classes A, B, C, D, or E or under Mode C Veil). If so, the FAA allows minimally-equipped aircraft to be exempt from the requirement IF IT CAN BE DONE SAFELY. It can be done safely in two ways. Get prior approval by requesting it (the FAA will want very complete info on position/airspeed/intentions). Or install an electrical system and transponder. If you choose the transponder route, the install must be IAW regulations and done by an authorized person.

The builder of an experimental cannot legally install radios, especially transponders. An avionics tech is the only one who can test and certify that all FAA required parameters are met. Well, splitting hairs, I suppose the builder can install it but it would be illegal to turn it on and test and certify its installation unless you are a licensed avionics tech.
 

bryancobb

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Old joke about a guy looking for an accountant. "How much is two plus two?" he asks the first guy, who responds, "Four." Asks the second guy the same question, who gives the same answer.

Third guy shows up. "How much is two plus two?" The accountant gets up, closes the door and window, and whispers, "How much would you like it to be?"

Can do pretty much the same trick for aircraft accident statistics.

In 2015, 1.6% of all US aircraft accidents were midairs. In 2019, after the implementation of the ADS-B mandate, the percentage was 1.0%

Yay! Yay?

But like Dana mentions, midairs are rare enough that the statistics can vary widely between years. Not only that, but the statistics count the NUMBER of aircraft involved in midairs. So the actual rate of occurrence of midair collisions as an event is a bit less than half the total.

("A bit less than half"? 2010 saw an ODD number of midairs. A Cirrus hit a glider towplane, thus involving three airplanes).

Plus... we cannot forget that the total number of accidents have decreased over the same period. Fewer midairs, yes, but the total count is down, too.

Instead, let's look a chart that combines the yearly number of aircraft involved in midairs with the total number of accidents. Midairs are tallied based on the left vertical axis, total accidents on the right.
View attachment 130428
So since 2008, midairs are trending downward...at about the same rate as overall accidents. So no, I'm not seeing any major effect of the ADS-B mandate. So don't go installing curtains in your aircraft windows.
View attachment 130429

Ron "Dern* liars, and" Wanttaja

* Curse that obscenity auto-correct! :)
ADS-B didn't become mandatory to help prevent mid-airs. That was only a by-product. ADS-B 's purpose is to replace the antiquated rotating radar system and the pilot-position-reporting system (if not in radar covered areas)...with a more accurate, more modern, less maintenance-intense means of tracking.
 

Pops

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On an experimental aircraft, or even on most light, certificated aircraft, a transponder is not required, period, regardless of whether or not the aircraft has an electrical system or when an electrical system was put in. In short, the FAA intends and allows simple, minimally-equipped aircraft to fly in the national airspace system. The next qualification is...does the owner CHOOSE TO HAVE A TRANSPONDER. If so, every aspect and rule of installation and operation must comply with FAR's. The third qualifier comes IF THE PILOT CHOOSES TO fly in any airspace where a transponder is REQUIRED (in classes A, B, C, D, or E or under Mode C Veil). If so, the FAA allows minimally-equipped aircraft to be exempt from the requirement IF IT CAN BE DONE SAFELY. It can be done safely in two ways. Get prior approval by requesting it (the FAA will want very complete info on position/airspeed/intentions). Or install an electrical system and transponder. If you choose the transponder route, the install must be IAW regulations and done by an authorized person.

The builder of an experimental cannot legally install radios, especially transponders. An avionics tech is the only one who can test and certify that all FAA required parameters are met. Well, splitting hairs, I suppose the builder can install it but it would be illegal to turn it on and test and certify its installation unless you are a licensed avionics tech.
Well said .
 
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