Never, ever, correct a mistake – CASA policy

[OZBUSDRIVER]

Leadie, forget ADS-B! Part61 WILL screw GA out of existence. That and Part42 and Part147 for AME training makes no sense for a whole library full of unnecessary regulation. If there is somewhere the fight is really need...Leadie...it is here. It probably is too late...once 2019 rolls around that's it for learning old school for GA maintenance.

[actus reus]

Lead,
I do not think a 'brain dump' of information makes a compelling point. OZ says it all.

Having flown in the 777 test programme in 1995, I can assure you that 1090 was a 'live'

concept then.

Plus, when we did the FAA/Boeing 'FANS in the Terminal Area' research in the later 90's (the

hook up of the United Airlines DC 10 sim in Denver, the Boeing 777 sim in Seattle and the

FAA ATC sim in Atlanta) which was aimed at Constant Descent and no voice comms

(including no 'clear to land' by voice), UAT was not going to cut it in any way shape or form

for the reasons (refresh rate) that OZ has articulated.

Find something else to go hard on. Excuse the pun.

[LeadSled]

ADS-B for Airbus and Boeing etc

Oz, Actus,
Have a look at the above thread, on Tech Log, re. availability of 1090ES ADS-B on Boeing.

A "live concept" in mid-1990s was not a roll-out, and FANS-1 was/is NOT in any way dependent on ADS-B or, indeed, a transponder --- but I am certain you know, is dependent on a datalink. That trials were held involving "in trail" separation and climbs and descents is a "so what", the first ones, and the whole Tennessee Valley trial used UAT -- as did Capstone. Indeed, one trial just used TCAS II presentations --- it worked, but only when there were only two aircraft in range, as there was no positive identification.

Of course 1090es was being talked about --- a conference I went to, in US, in 1996, was largely devoted to the subject, and all the potential problems, if 1090ES was adopted, instead of the intended (since the 1980s) broadband, either VDL-4 or UAT. As a matter of interest, at that stage, it was VDL-4 that was widely favored,(including IFALPA and IAOPA and most European NAA at ICAO) except by ATA and the US major avionics manufacturer, for reasons already posted.

See if you can get a copy of the article on the latest problems in the 1030/1090 frequencies, in the latest Aviation Week (AWST)--- and the expensive work-rounds proposed, which MIGHT include a retrofit of an entirely new transponder/TCAS (TCAS III??).

All problems, I might point out, created by or exacerbated by 1909ES ADS-B, and yet such a small proportion of the US airline fleet is equipped.

That UAT/VDL-4 is not a transponder has never been disputed, but it is significant that nobody has yet built and sold in large numbers a TCASII that picks up the ADS-B IN functions, because it adds no new functionality to the effectiveness of TCAS II v. 7.x.

FAA simply do not see UAT or 1090ES ADS-B as anything more than a datalink --- as we now have proven (those of us who can add up have always known) keeping the "traditional" transponder, and having ADS-B as a stand alone part of a multi-use broadband transceiver ( as most of GA in US can do) is cheaper by far than mandating 1090ES.

There are some serious attempts to re-write history here --- UAT was developed largely by UPS, who bought an electronics firm that built the original equipment (Apollo Corp.??) , and to suggest that a refresh rate was an inherent limitation is just to laughable for words. VDL-4, the first to go into daily operation for ATC, was unquestionably successful, but lost out in the politics, as did UAT.

That UAT or VDL-4 did NOT impinge on the 1030/1090 frequencies would have been critical to avoiding the problems now (already) occurring, and the fact that they were "stand-alone" systems, compared to producing 1090ES ADS-B OUT (let alone IN) was what made them a fraction of the cost to fit any aircraft.

You do understand, do you, who and what Mitre Corp. is, what it is not is a commercial corporation. It had no commercial interest in the outcomes, but its analysis and forecasts, 20 years later, as blindingly accurate.

As is clear, from the AWST article, the long forecast chickens are coming home to roost, and the cost to the industry is potentially huge.

Funnily enough ( and it is really funny- Ha! Ha!) the cheapest solution to the emerging problems for operations in the US might well turn out to be mandating UAT for all aircraft, and turning 1090ES ADS-B off (back to Mode S only) in US airspace (and western Europe) --- a cheaper solution than developing and deploying a whole new transponder fit, substituting wide area multilateration for SSB, and a few other very expensive tweeks, like a whole new major hardware/software upgrade for the already seriously delayed FAA ATC upgrade.

After all, the ground infrastructure already exists, as does the software --- all FAA ADS-B ground stations are dual 1090ES/UAT.

All so very sad, and bleeding expensive for a not even second rate system.

Tootle pip!!

[OZBUSDRIVER]

In September 1998 there were only a handful of aircraft running gear built by MITRE. In 1999 Capstone started in Alaska...UPS AT were successful with their MX20 and GX60 GPS linked with the UAT datalink. OK...my first error on UAT in a long while...it is the TIS uplink that is delayed. UAT transmits position once a second. History on Leadsled's datalinks

EDIT- MITRE Center for Advanced Aviation System Development 1995 first concept of UAT

The Universal Access Transceiver Digital Data Link

The Universal Access Transceiver, or UAT, is the two-way digital data link employed in the Capstone system. It is a high-bandwidth, multi-purpose, low cost data link. UAT was initially developed by CAASD. CAASD has worked with data link technology for several years, and its work in related areas of aviation research is part of Capstone's legacy. Developed under internal research and development funds at MITRE beginning in 1995, the UAT was originally conceived as a simple, multifunction broadcast data link alternative for small aircraft. Following the successful flight demonstrations of ADS-B, FIS-B and TIS-B as part of CAASD efforts, United Parcel Services (UPS) Aviation Technologies developed a commercial version of UAT. Subsequently, UAT was included in the winning proposal by UPS Aviation Technologies for Capstone avionics and ground stations. RTCA has begun developing UAT standards, with CAASD again poised to play a key role.

EDIT- Whilst UAT is many things....somebody has to pay for it. The FAA justifies UAT to keep GA off 1090ES and contributing to FRUIT. Also to decom some 70% of the 130 SSR facilities across the nation. Compare this with the cost savings put forward by Dunstone here in the early days of ADS-B for a handful of SSR sites in the J Curve.

Regardless. AirServices 1090ES was part of ICAO mandate for full ATM coverage ABV FL280.

[LeadSled]

Folks,
An interesting new post on Tech Log suggests that FAA is going to require dual UAT/1090ES ADS-B, with the 1090ES switched back to Mode S (or C ??) below 18,000, the US transition altitude ----- due the mounting problems with 1090ES frequency saturation.
This is a new one on me, I am not really convinced it is correct, but it would be one answer to all the problem outlined in last week's AWST article.
I have asked the poster for references.
Tootle pip!!

[OZBUSDRIVER]

Interesting...Flightradar24 does use third party receivers. The post proves the need for FDE!

Leadsled can u link that prune thread?

[aroa]

Here's a quote that says it all....

No major institution can expect to preserve a shred of public trust if it manifestly fails to understand such a basic concept of accountability.

Thats our CAsA for ya !!