Operating without a transponder still possible post 2020?

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cluttonfred

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According to the font of all knowledge, Wikipedia ;-), "by 2020 all aircraft owners will be required to have ADS-B Out capabilities when operating in any airspace that currently requires a transponder (airspace classes A, B, and C, and airspace class E at certain altitudes)" in the USA.

Has there been any indication that the ability to operate without a transponder in aircraft without an engine-driven electrical system will change after 2020? Will the ADS-B requirement increase the amount of airspace not normally open to aircraft without a transponder?

I am just thinking about whether or not it really makes sense to plan an aircraft without an engine-driven electrical system in the next few years, or whether there will be so many restrictions on where I can fly that I may as well bite the bullet.

Cheers,

Matthew
 

cluttonfred

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Right, but isn't that already the case unless you receive prior approval? Will ADSB change anything in 2020 in that respect?
 

Wanttaja

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Right, but isn't that already the case unless you receive prior approval? Will ADSB change anything in 2020 in that respect?
That's my understanding, that the "What you must have to fly where" rules haven't changed, other than requiring ADS-B out as well as the transponder. ADS-B will be required within the 30-mile veil around Class B, with the exception of aircraft without engine-driven electrical systems (same as the current rule for transponders).

Ron Wanttaja
 

proppastie

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they just did something to the gliders...not sure what, but thought they needed transponders, not sure where or how high. That could be bad news in the future for part 103 or aircraft without engine-driven electrical systems
 

Rockiedog2

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thankfully so far I can avoid that airspace. occasionally tho I want to enter it....I would have gone to meet TFF but he's in the Mem Class B. I got no txp, mode c or comm
 

Arthur Brown

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With the improvement in battery cells and solar PV cells, will moderate avionics inc transponder be possible without an engine alternator?

Can anyone actually give the rated current draw of a 12 or 24/28 volt transponder, and the rest of a set of avionics. I'd be reasonable certain that by then with some technological advances 12v 5a will be supportable from LiPo batteries for very moderate weight and a 40 ish watt solar panel may well be possible to delay discharge. Realistically you only need electricity for the flight duration that a tank of fuel provides.
 

Turd Ferguson

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Has there been any indication that the ability to operate without a transponder in aircraft without an engine-driven electrical system will change after 2020? Will the ADS-B requirement increase the amount of airspace not normally open to aircraft without a transponder?

I am just thinking about whether or not it really makes sense to plan an aircraft without an engine-driven electrical system in the next few years, or whether there will be so many restrictions on where I can fly that I may as well bite the bullet.
If I just have a local flying airplane and live in Class E/G airspace, like I do, no way I'm installing that garbage. It should still be possible to fly coast to coast without an electrical system although they are trying to make it difficult.
 

Wanttaja

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With the improvement in battery cells and solar PV cells, will moderate avionics inc transponder be possible without an engine alternator?

Can anyone actually give the rated current draw of a 12 or 24/28 volt transponder, and the rest of a set of avionics. I'd be reasonable certain that by then with some technological advances 12v 5a will be supportable from LiPo batteries for very moderate weight and a 40 ish watt solar panel may well be possible to delay discharge. Realistically you only need electricity for the flight duration that a tank of fuel provides.
One of the Fly Baby group doesn't have an electrical system, and flies his plane with a radio and a transponder. Just has a moderately-sized motorcycle battery, and it does him fine.

Ron Wanttaja
 

proppastie

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One of the Fly Baby group doesn't have an electrical system, and flies his plane with a radio and a transponder. Just has a moderately-sized motorcycle battery, and it does him fine.

Ron Wanttaja
so after 2020 in order to be seen by radar in a high traffic environment.....radio,transponder,encoder,ADSB out,.....how big a battery for 2 hr. of flight?, Those transmitters squirt out some juice.
 

fly2kads

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With the improvement in battery cells and solar PV cells, will moderate avionics inc transponder be possible without an engine alternator?

Can anyone actually give the rated current draw of a 12 or 24/28 volt transponder, and the rest of a set of avionics. I'd be reasonable certain that by then with some technological advances 12v 5a will be supportable from LiPo batteries for very moderate weight and a 40 ish watt solar panel may well be possible to delay discharge. Realistically you only need electricity for the flight duration that a tank of fuel provides.
I hope that some of our active glider pilot friends will chime in, but I do know that there are an increasing number of sailplanes equipped with transponders, relying on battery power. I recall seeing a pretty slick setup where the sailplane's trailer had a solar panel on top for keeping the battery charged between flights.

One of the retailers of soaring "stuff" has put together this handy comparison chart, which includes power consumption:
https://www.cumulus-soaring.com/transponders.htm#Transponder_Comparison_Table

It looks like "typical" current ranges from .34 to .7 amps. I think this typical current is an average value, since the transponder cycles between standby and transmission modes.
 

Glider

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I wish we could move beyond the system of radars. and transponders. Maybe it is impractical, but I don't see why a terrestrial/space cell infrastructure couldn't be used to receive, and report, positions. Maybe the system wants to geographically distribute controllers to protect the whole system from regional failures.

Ham radio has APRS, and with some simple software, could provide this kind of functionality via terrestrial and space asserts.
 

fredoyster

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With the improvement in battery cells and solar PV cells, will moderate avionics inc transponder be possible without an engine alternator?

Can anyone actually give the rated current draw of a 12 or 24/28 volt transponder, and the rest of a set of avionics. I'd be reasonable certain that by then with some technological advances 12v 5a will be supportable from LiPo batteries for very moderate weight and a 40 ish watt solar panel may well be possible to delay discharge. Realistically you only need electricity for the flight duration that a tank of fuel provides.
That's right. A LiPo battery with a small solar panel and controller will be plenty. Modern transponders and modern comms draw less than an amp average. Transponders put out 250 watts or so, but for microseconds, so the average power is still very low. Comms can draw 5 amps or more on transmit, maybe a couple amps if you're driving a speaker turned up loud, but otherwise less than an amp.
 

Turd Ferguson

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I wish we could move beyond the system of radars. and transponders. Maybe it is impractical, but I don't see why a terrestrial/space cell infrastructure couldn't be used to receive, and report, positions.
Don't throw in the towel just yet. ADS-B won't be required until the date comes with no modifications. There is a lot of push for modification as once again the FAA wants equipment that is already obsolete.
 

cluttonfred

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Personally, I don't mind the idea that ADSB, preferably integrated out and in, would become required for everyone as long as the weight, power consumption and cost are brought down to reasonable levels. With today's technology it just should not require thousands of dollars--that's the TSO and insurance cost driving it up, not the cost to make the equipment. FAA needs to be engaged with manufacturers to create reasonable specs that that can be met without excessive costs to actually encourage everyone to adopt the technology willingly, from Citation jets to gliders.
 
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BBerson

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Invented, or proposed? It would have been very difficult to achieve with 1945 technology.

Dana
I think invented by RCA. Not sure if they demonstrated it. It gives the pilot a radar picture in the cockpit for self seperation.
The FAA went with ground based controllers. The units would have been heavy then. Today is different, a cell phone could do it.
Each airport could have a 5 watt transmitter and small radar unit to broadcast a map that the pilot would use to approach with text instructions to hold if needed. All computer generated.
The whole Teleran system was detailed in Fred Wiecks book. (Ercoupe designer)
 

Pops

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I think invented by RCA. Not sure if they demonstrated it. It gives the pilot a radar picture in the cockpit for self seperation.
The FAA went with ground based controllers. The units would have been heavy then. Today is different, a cell phone could do it.
Each airport could have a 5 watt transmitter and small radar unit to broadcast a map that the pilot would use to approach with text instructions to hold if needed. All computer generated.
The whole Teleran system was detailed in Fred Wiecks book. (Ercoupe designer)

Fred Wiecks was way ahead of the time in several areas. I got the privilege to spent some time talking with him at Osh back in the 70's.
 

Arthur Brown

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Personally I think that today's avionics will be "old" in four years and something will be waiting to replace it, but I suspect that the best of the then "old Tech" will be supportable from dry or rechargeable batteries for long enough to cover a day of flying.

With (now -it may be beaten by then!) good retail technology a 40w solar panel built into the airframe would keep a LiPo battery in good order for all the flying you would want to do in a day while powering some useful nav and coms.

There is a clip on Youtube of a model plane using inbuilt solar panels for flight power.
 
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