ADS-B

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GAHorn
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Re: ADS-B

Post by GAHorn »

flyboy122 wrote:...No, it is not misleading. ...No, it is not instant. But it is orders of magnitude faster than the way we used to do it.

DEM
It is misleading because their immediate response is only a telephone-call... it is NOT the actual sighting/rescue of the airplane/occupants.
juredd1 wrote:Your knowledge level on this subject is way beyond mine so please over look my stupidity in these questions....More towers to come I am sure but that system called cellular service has a lot of towers and we all know how consistent that is.

Not trying to shot it down just trying to understand it better.

Justin
The ADS-B system WILL have a cellular-phone type system of towers....to gather the transmitted data from aircraft and supply it to ATC.

A simple and graphic description of the entire ADS-B system can be found here: http://adsbuniversity.com/ads-b-university
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
flyboy122
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Re: ADS-B

Post by flyboy122 »

gahorn wrote:
flyboy122 wrote:...No, it is not misleading. ...No, it is not instant. But it is orders of magnitude faster than the way we used to do it.

DEM
It is misleading because their immediate response is only a telephone-call... it is NOT the actual sighting/rescue of the airplane/occupants.
Gahorn, with all due respect I don't quite understand where you are coming from here? The phone call is Step 1 in the process, followed by appropriate search and rescue measures. It's not like they call you on the phone asap and then kick back and twiddle their thumbs for 3 hours. The phone call is a vital first step in either expediting the search ("Yes my husband was flying up to Smith Lake, go find him!") or alleviating the search ("Oops, dropped it during annual inspection. Thanks for the heads up.") And no matter what the response, it is orders of magnitude faster than the way we used to do it.

If you don't want to buy a 406 ELT, don't. It's your money and your hiney. But don't try to justify it by saying they don't work. If it makes you feel any better, I have a hard time swallowing airframe parachutes. Seems overkill to me. But the guys who have rode one down are believers! And the numbers are there....they work. Doesn't mean I'll buy one, but I'm not gonna tell someone else don't waste their money.

DEM
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GAHorn
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Re: ADS-B

Post by GAHorn »

The point I'm attempting to make is.... That ELT performance-expectations are outdated in an ADS-B system.
ELT activation merely notifies authorities that an ELT is activated....for whatever reason... and the system-response for either a 406 OR a 121.5 unit is a telephone call to attempt contact with someone who may, or may not, have anything to do with the flight in question.
That is not an active search and rescue matter, it's a clerical matter, and it makes absolutely no difference on what frequency the ELT transmits to accomplish that.

While 406 ELTs certainly transmit more accurate location ....and despite the fact that 121.5 ELTs have been relegated to near-obsolescence purely because they "can"......) then 406 is the future despite the fact that the notification capabilities are only marginally better than the previous 121.5 system ....and that the notification-system is much WORSE and LESS-capable than an ADS-B OUT system in which everyone will soon be required to be equipped in order to fly in most controlled airspace.... therefore ELTs, including 406 units are obsolete if the authorities will simply wake up and recognize the applicability of ADS-B to search-and-rescue operations. IN a fully functional ADS-B system, no ADS-B OUT equipped aircraft will be better equipped with an ELT than without .... if the system designers will merely acknowlege this simple capability.
That ONE additional feature alone.... would do more to promote ADS-B than anything else. (And it is ridiculous to encourage GA owners to "upgrade" to 406 ELTs while simultaneously insisting they purchase ADS-B OUT equipment which can more reliably accomplish the same tasks as well as many MORE.

I am NOT BAD-MOUTHING 406 ELTs. I am only pointing out that their usefulness is negated by a well-designed ADS system that takes full adavantage of its capabilities....and THEREIN lies the (presently-ignored) incentive to participate in ADS-B for small operators.
'53 B-model N146YS SN:25713
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An originality nut (mostly) for the right reasons. ;)
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GAHorn
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Re: ADS-B

Post by GAHorn »

Simple.... require non-ADS-B OUT aircraft to have ELT's.... but that's no reason to make ADS-B OUT aircraft to waste addt'l money on it. (and it would encourage more people to go to ADS-B ...which would also make that technology as affordable as a simplistic ELT.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
bagarre
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Re: ADS-B

Post by bagarre »

Exactly why do we need WAAS as a requirement of ADSB?
I'd think you'd only need the precision of WAAS for IFR traffic. ADSB or not, VFR is still see and avoid.
I'd like to see a cheap non WAAS ADSB out option that restricted me to VFR below 10,000 feet. Heck, could be a handheld at that point.

I don't see the point of that much precision unless you're flying in the system.
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DaveF
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Re: ADS-B

Post by DaveF »

NavWorx has a one-box solution with GPS that can wifi to portable devices. No panel-mount installation required. I hope more of this kind of thing comes along in the next five years.
flyboy122
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Re: ADS-B

Post by flyboy122 »

gahorn wrote:The point I'm attempting to make is.... That ELT performance-expectations are outdated in an ADS-B system.
ELT activation merely notifies authorities that an ELT is activated....for whatever reason... and the system-response for either a 406 OR a 121.5 unit is a telephone call to attempt contact with someone who may, or may not, have anything to do with the flight in question.
That is not an active search and rescue matter, it's a clerical matter, and it makes absolutely no difference on what frequency the ELT transmits to accomplish that.

.
With all due respect, that's not true. 121.5 is a low power, passive system. IF (big if) someone happens to detect the signal, all they know is that somewhere in the general area an ELT went off. Then they go through a homing process to find it. In reality they way it usually works is an aircraft is reporting missing, they go to the general area, and then they start looking for the signal. When your 121.5 ELT goes off, NOBODY IS GOING TO CALL YOU. They may start a search, but they don't what they are looking for.

406 is an active system. It pings a satellite which sends a command to a constantly monitored center. Embedded in this signal is a code specific to your ELT. Each code is registered, and when the pull it up they know all kinds of info (based on the form you fill out when you register) such as aircraft type, colors, who to call, etc... This gives the responders a massive heard start on figuring out who, what, when, or where. Thus the biggest difference is actually on the clerical side.

Truth be told, once they get our searching in the general area, other than knowing what they are looking for, there probably isn't that much difference in homing signals (unless you had the GPS hooked up to your 406, in which case it broadcasts last known GPS position). The biggest difference in the 406 is the head start they'll get on that search.

As to your ELT vs ADSB argument, you are correct. A properly equipped and monitored ADSB system could be used to pinpoint a downed aircraft.....or someone who landed in the field in his backyard (like I do in winter...skis are fun!), or someone who's transponder crapped out, or...well you get the point. I'll take my chances with the ELT. :)

DEM
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GAHorn
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Re: ADS-B

Post by GAHorn »

I believe the major difference between the two systems is that the SAR folks can more easily determine if the ELT-alert is merely a "nuisance" alert as opposed to an actual aircraft down....because they can quickly identify the owner of the registered 406 unit (something they've never bothered to do with 121.5 units.) Of course, the coordinates of the alert is also a major advantage, as is the method of reception (satellite).
But that does not validate the expense of the system and most authorities recognize that point, I believe, as evidenced by the lack of forced requirements for installation (in the U.S.)

There is nothing the 406 system will do that cannot be accomplished with a properly monitored ADS-B system, and since the 406 is not required equipment ...but ADS-B is soon to be.... I'm waiting for the historical drop in price of new-technology. (I've already been burned by the mandated HD-TV ($5K)and my 1961 lap-sized calculator ($450) and 1985 Radio-Shack Cell phone ($1800 puchase, plus $1100/mo. service fees) I'd never have bought that attache'-case sized cell phone if the employer hadn't mandated and paid for it.

Hopefully ADS-B in/out will also plummet as competition heats up.

BTW, there are several ADS-B OUT units which will work with present, common transponder/encoders.... i.e., no need to replace the txdr also. My Narco AT-150 might make it another decade. :lol:
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
bagarre
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Re: ADS-B

Post by bagarre »

How would the ADS-B system know the difference between an aircraft that just crashed vs one that just landed on a sand bar or grass field or lost electrical power?

There would need to be some way of alerting the system that there was an impact or something out of the ordinary...other than it just dropped off the screen.

I think the ELT system should be an opt in as well. If I want an ELT, I should be able to buy and pay for whatever service I want.
That's like requiring every car and motorcycle on the road be retrofitted with OnStar.
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GAHorn
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Re: ADS-B

Post by GAHorn »

All it would require would be an ATC software item. ATC computers know terrain and landing areas. ADS-B tracking will update aircraft position every 3 seconds, so if ATC computers detected a rate-of-deceleration (such as sudden stoppage or such as an altitude conflict with terrain coupled with sudden-stoppage).... a deceleration greater than ordinary.. it would trigger an alert.....on an aircraft whose position was known by WAAS-GPS and whose registration is also known. An aircraft travelling 80 mph which is travelling at zero on the next update will have hit something, especially if it's ADS-B position has stopped transmitting. It's a dirt simple matter. (sorry for the pun)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
bagarre
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Re: ADS-B

Post by bagarre »

I think that software would cost more than the ObamaCare website.
voorheesh
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Re: ADS-B

Post by voorheesh »

I talked about this with an ATC specialist who I work with and he told me he often hears comments from general aviation pilots that a common sense solution is "just a software change" or another is "my IT guys could fix this in an afternoon". According to him, most GA pilots do not have a clue as to the structure and depth of the ATC system we work with today let alone what is gradually evolving in next gen. To start, take a look at the screen on Flight Aware that shows all the IFR traffic existing in one moment of time and then extend that workload indefinitely, 24/7. And we are not talking PCs and Macs here but gangs of computers that function world wide and deal with amounts of data that would make Obamacare pale in comparison just on the basis of size. Another important aspect of the ATC system is that lives depend upon it on a real time (instantaneous) basis, quite literally.

The FAA was faced with upgrading its ATC system in the mid 1990s. In fact, that system was continually being updated but the tipping point came when it was clear the industry was moving ahead of the agency in technology. UAL, which has been in the forefront of aviation introduced Future Air Navigation System (FANS) that allowed it to save hours of flight time between Eastern US and Asia by sending accurate position reports to its dispatch and ATC via satellite. The US Military was already using the satellite system and it became very obvious that this would be the next evolution of modern air transportation. The decision to replace the radar based ATC to satellite based was financially driven because the industry demanded it and efficient maintenance of an aging system that dates back to late 50s would not be possible. DOT/FAA uses long term, 25 year planning and then translates action plans into the shorter term 3-5 year congressional budget cycle. Everything this department does must be approved and funded in that manner. It evolved from a concept to a viable nuts and bolts system through a comprehensive engineering exercise that dealt with long term goals, transition, system integration, and rule making. ICAO was involved from the beginning and the system will be in place worldwide (Vietnam for example is fully operational Nextgen).

In this process, system design characteristics were specified and I do not believe that an ELT function was ever part of it. I could be mistaken, but it would involve more than a software change. Aviation systems require reliability and what engineers refer to as "elegance" in that they account for multiple variables and provide solutions that will work to nearly 100% of the stated goal. Solutions can not interfere with other functions and should also be as independent as possible. So if your goal is to have automation that will identify the location of a crash, the first thing you want to define is the crash. The accepted technique for that is the identification of "G" forces which, from an engineering point of view, are common in crashes. That is the basis of ELT design. An ELT has a simple switch activated by a force consistent with a accident. The next part is the where. The 406 ELT contains a gps and a simple transmitter that sends the information to a satellite that is monitored by SAR. This system is relatively inexpensive and is highly reliable. It is stand alone and does not need ATC or any other entity which would introduce an unnecessary variable in the system. Most GA aircraft are currently equipped with ELTs and this requirement has been around for a long time. This translates into minimal impact on GA pilots who have been using ELTs in one form or another for over 40 years. Why change now? I can not see the benefit, but (knowing me) I may be missing something.

One other interesting airline story, because we must remember that the billion dollar airline industry is driving this evolution. In the 1980s Southwest Airlines was perfecting an airline business model based on high aircraft utilization and its resultant lower costs. They used B737 aircraft exclusively and strived to have a standardized fleet which lowered maintenance and crew training costs. At the same time, the industry was moving ahead and introducing FMS equipment, IRUs, AHRS, digital stuff. Southwest resisted. CEO, Herb Kelleher was reported to say "I don't need FMS, that is what I pay pilots for". True enough, but then Boeing came back and told one of their best customers that if he wanted to keep buying airplanes with round gauges, it was going to cost more. Technology was driving the train. Then he started to hear that some of his equipment might not be compatible with some of the new fangled approaches such as a charted FMS visuals, and dad gummit, some of his flights might be delayed which does not fit in with the high utilization model. So guess what? Southwest which is probably one of the finest aviation companies ever, made adjustments and they now fly one of the most advanced fleets in the world. In fact Southwest found that the GPS based technology allows them to fly Required Navigation Performance (RNP) based routes which save time and money, thus ensuring their company's success. Southwest has an open mind. It is ready for change and then makes the best of it. Good lesson for the rest of us, I think. To me this story epitomizes how the aviation system is evolving and I believe GA will look back on all this 20 years from now and will remember radar and VORs the way old-timers now reminisce about A N ranges and airway beacons.
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Bruce Fenstermacher
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Re: ADS-B

Post by Bruce Fenstermacher »

So I'm enroute to convention. I unbox my ADS-B (I had it ready to sell) that I've never really used. Fired it up and off into the blue I went. Pretty soon I had weather (which pretty much matched the internet weather I was still receiving over 4G) and there where those airplanes representing traffic. What, holy crap there is a plane ascending right up under me. Evasive maneuver to the left. Boy was that close as I'm looking out the right side of the aircraft. What, holy crap the dam traffic has turned right for me. Evasive maneuver to the right, I'll lose that sucker for good this time. Where is he anyway. Waaaa the boogie is right under me again.

That's about when I realized. I'm trying to loose my own shadow. My target as broadcast to the other planes. :oops:
CAUTION - My forum posts may be worth what you paid for them!

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voorheesh
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Re: ADS-B

Post by voorheesh »

Last post, I promise. I am retiring from this. If we are talking about a portable device that has ability to get traffic (TIS-B or ADS-B where available/FIS or FIS-B), I do not consider those part of the equation. They are nice to have. Help with Situational Awareness. But they are not Next Gen.. Not even close. Not what I have been yaking about. Hope you guys enjoy the get together. Wish I could be there! :)
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GAHorn
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Re: ADS-B

Post by GAHorn »

OK, then.... add a G-switch to the ADS-B OUT transmitter and ....VOILA!...no more need for ELT! (ADS-B uses a cell-phone-tower system to communicate to ATC.) The point is.... unnecessary and useless, expensive, out-of-date equipment requirements are being placed upon GA.... Why? so that the "airline driven" ATC system can operate.

CAPITAL B...CAPITAL S. The truth is they (airlines) want little airplanes out of the sky...and AOPA is not defending the little guys anymore.

ADS-B is not necessary for the vast majority of GA airplanes who operate under 10K and under Mode-C veils. But it is being forced upon them.

(And, BTW, while it makes for an expedient way to explain it by saying Herb Kelleher said so... the real reason SWA resisted modern avionics was because the vast majority of his pilots...former A.F. F-16/F-15 types didn't understand FMS. They were used to flying TACAN and being directed using targeting radar. Glass cockpits befuddled them.
I just completed teaching a recent F-18 pilot what FMS is all about and frankly, I'm appalled that the military is so far behind in technology. I had thought they'd have the latest and greatest....but, not so. 8O
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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