change in ADS-B rule interpretation!

from https://www.federalregister.gov/arti...rt-air-traffic


Under paragraph (b)(1) of that section, in order to operate an aircraft below 18,000 feet MSL and in identified airspace described subsequently in § 91.225, an aircraft must be equipped with equipment that "meets the requirements of TSO-C166b; or TSO-C154c . . .". In reviewing these paragraphs, the FAA notes that the regulatory text implies that the equipment must meet all the requirements of the referenced TSOs. As the ADS-B Out rule is a performance-based rule, it was not the FAA's intent to arguably limit operators to only install equipment marked with a TSO in accordance with 14 CFR part 21, subpart O. The FAA's intent was to permit equipment that meets the performance requirements set forth in the referenced TSOs.


In the NPRM, the FAA proposed in § 91.225(a)(1) and (c)(1) that the equipment installed "Meets the performance requirements in TSO-C-166a" (72 FR 56947, 56971). The inadvertent removal of the word "performance" in the paragraphs implementing these provisions in the final rule was in error and resulted in confusion as to whether the regulation permits other than equipment marked with a TSO, provided that equipment met the specified performance requirements.


So it looks like the equipment must meet the TSO performance requirements, but it doesn't necessarily have to be TSO'd

This is great news!

On Tuesday, February 10, 2015 at 7:10:40 AM UTC-6, Bob Pasker wrote:
from https://www.federalregister.gov/arti...rt-air-traffic


Under paragraph (b)(1) of that section, in order to operate an aircraft below 18,000 feet MSL and in identified airspace described subsequently in § 91.225, an aircraft must be equipped with equipment that "meets the requirements of TSO-C166b; or TSO-C154c . . .". In reviewing these paragraphs, the FAA notes that the regulatory text implies that the equipment must meet all the requirements of the referenced TSOs. As the ADS-B Out rule is a performance-based rule, it was not the FAA's intent to arguably limit operators to only install equipment marked with a TSO in accordance with 14 CFR part 21, subpart O. The FAA's intent was to permit equipment that meets the performance requirements set forth in the referenced TSOs.


In the NPRM, the FAA proposed in § 91.225(a)(1) and (c)(1) that the equipment installed "Meets the performance requirements in TSO-C-166a" (72 FR 56947, 56971). The inadvertent removal of the word "performance" in the paragraphs implementing these provisions in the final rule was in error and resulted in confusion as to whether the regulation permits other than equipment marked with a TSO, provided that equipment met the specified performance requirements.


So it looks like the equipment must meet the TSO performance requirements, but it doesn't necessarily have to be TSO'd

This is great news!

AOPA and EAA have been lobbying for such a change for quite some time now. I wonder if this also applies to operating GA aircraft and gliders in and under B and C airspace. If in fact TSO'd equipment is NOT necessary under 18,000', that would open the door to cheaper, even portable ADS-B out equipment, just what the doctor ordered.

the way I read (b) [amended as per my original email] and (d) is that yes, this includes Class B and C airspace


(b) After January 1, 2020, and unless otherwise authorized by ATC, no person may operate an aircraft below 18,000 feet MSL and in airspace described in paragraph (d) of this section unless the aircraft has equipment installed that--
(1) Meets the requirements in--
(i) TSO-C166b; or
(ii) TSO-C154c, Universal Access Transceiver (UAT) Automatic Dependent Surveillance-Broadcast (ADS-B) Equipment Operating on the Frequency of 978 MHz;

(d) After January 1, 2020, and unless otherwise authorized by ATC, no person may operate an aircraft in the following airspace unless the aircraft has equipment installed that meets the requirements in paragraph (b) of this section: (1) Class B and Class C airspace areas;

I believe that the GPS reciever still needs to be WAAS compliant to provide ADSB out data. The key would be to approve portable ADSB out devices, currently available for about $1500 with WAAS GPS built in, for use in glider tow and gliders. It sure would save out club a heap of $$$ for the tow plane, we are under the class b shelf.

BillT

On Tuesday, February 10, 2015 at 12:20:37 PM UTC-8, Bill T wrote:
I believe that the GPS reciever still needs to be WAAS compliant to provide ADSB out data. The key would be to approve portable ADSB out devices, currently available for about $1500 with WAAS GPS built in, for use in glider tow and gliders. It sure would save out club a heap of $$$ for the tow plane, we are under the class b shelf.

BillT

I thought most GPS units installed in gliders (at least in the last few years) were WAAS compliant.

Most GPS units in gliders may be WAAS compliant, but with the previous language they were not approved to provide adsb out because they do not have the TSO Certification.
BillT

On Tuesday, February 10, 2015 at 8:17:50 PM UTC-8, Bill T wrote:
Most GPS units in gliders may be WAAS compliant, but with the previous language they were not approved to provide adsb out because they do not have the TSO Certification.
BillT

It appears in the new rules that it only has to meet the performance requirements. Furthermore the wording would suggest it is up to the installer to decide that it does until the FAA indicates otherwise? Which is reversed from TSO. Almost any GPS engine is WAAS compliant now. But I don't know what else is involved in meeting the 'performance requirement'. It seems like there is hope though, given that the spec was written while vacuum tubes were still in common use.

I'm sure Darryl will jump in at any moment and set me straight.

On Wednesday, February 11, 2015 at 12:39:47 AM UTC-6, jfitch wrote:
On Tuesday, February 10, 2015 at 8:17:50 PM UTC-8, Bill T wrote:
Most GPS units in gliders may be WAAS compliant, but with the previous language they were not approved to provide adsb out because they do not have the TSO Certification.
BillT

It appears in the new rules that it only has to meet the performance requirements. Furthermore the wording would suggest it is up to the installer to decide that it does until the FAA indicates otherwise? Which is reversed from TSO. Almost any GPS engine is WAAS compliant now. But I don't know what else is involved in meeting the 'performance requirement'. It seems like there is hope though, given that the spec was written while vacuum tubes were still in common use.

I'm sure Darryl will jump in at any moment and set me straight.

More on the subject this morning on the AVweb website:
http://www.avweb.com/avwebflash/news...e223533-1.html

I'm also eager to see what Darryl will make of this.

On Tuesday, February 10, 2015 at 5:10:40 AM UTC-8, Bob Pasker wrote:
from https://www.federalregister.gov/arti...rt-air-traffic


Under paragraph (b)(1) of that section, in order to operate an aircraft below 18,000 feet MSL and in identified airspace described subsequently in § 91.225, an aircraft must be equipped with equipment that "meets the requirements of TSO-C166b; or TSO-C154c . . .". In reviewing these paragraphs, the FAA notes that the regulatory text implies that the equipment must meet all the requirements of the referenced TSOs. As the ADS-B Out rule is a performance-based rule, it was not the FAA's intent to arguably limit operators to only install equipment marked with a TSO in accordance with 14 CFR part 21, subpart O. The FAA's intent was to permit equipment that meets the performance requirements set forth in the referenced TSOs.


In the NPRM, the FAA proposed in § 91.225(a)(1) and (c)(1) that the equipment installed "Meets the performance requirements in TSO-C-166a" (72 FR 56947, 56971). The inadvertent removal of the word "performance" in the paragraphs implementing these provisions in the final rule was in error and resulted in confusion as to whether the regulation permits other than equipment marked with a TSO, provided that equipment met the specified performance requirements.


So it looks like the equipment must meet the TSO performance requirements, but it doesn't necessarily have to be TSO'd

This is great news!

Unfortunately this is just non-news. Kind of as the notice implies this is just a minor typo correction and really does not mean what you are hoping it means.

Many CFR 14 regulations that specify carriage of a TSO device use similar "meets requirements" wording. e.g. 14 CFR 91.215 which mandates transponder carriage, there you go opening paragraph... "...must meet the performance and environmental requirements...". What this means if you end up in an argument with an FAA inspector over an installation where some box does not have a TSO document, well that can get complex, but hopefully this area is somewhat familiar to A&Ps actually installing stuff in aircraft. And often comes up in discussion including on r.a.s. before.

Unfortunately say reading TSO-C-166a won't help most people, as with most TSO's it just refers to RTCA standards documents, in this case largely DO-260A, but it also pulls in other RTCA standard. And you can't get free access to and of those standards. Whether governments should be basing regulations on proprietary documents that citizens do not have free access to is a longer discussion.

And these TSOs affect the UAT or 1090ES Out (or Out/In) part of the ADS-B picture, the specification of the GPS input required to provide ADS-B Out in a certified aircraft and/or to meet the 2020 carriage mandate requirements also get captured in enough additional places outside of that one specific chain of regulations/TSO/RTCA standards.

Nobody is going to be helped to produce anything as radical as a low-cost portable ADS-B Out transmitter based on this minor change in wording. The device still has to meet a complex set of RTCA requirements, that preclude doing exactly that, And for example the device still has to be connected to altitude encoders, Mode A setting controls, etc. And to be installed in a certified aircraft still require field approval based on a prior STC install that paired a specific ADS-B out device and IFR/WAAS spec GPS. This is mostly an "inside-baseball" thing that might be useful for say a manufacture of avionics to enter the USA market faster then they otherwise would, and avoid a little TSO related delay, but not RTCA standards compliance testing, etc.

And when discussing aviation regulations in any way with TSOed or IFR or WAAS GPS we are not talking about your typical consumer GPS that has WAAS. It has a specific complex set of technical requirements, that a consumer device cannot meet, and cannot meet the "performance requirements of". Things like hoping to ever broadly utilize more COTS GPS for ADS-B Out purposes in the USA absolutely requires new regulation that does *not* require meeting the performance requirements of the TSOs that specify that today (e.g. TSO-C145c). In fact the relevant regulations and ACs in use today already us "meet the performance requirement of TSO-C145" etc. type wording, that does not help jack with solving the complex/expensive GPS requirements for ADS-B out. Which is why TSO-C199 which has come up in other threads here recently, is interesting, as it does exactly that.... for limited airborne traffic awareness/collision avoidance beacon only purposes it completely steps away from any of these "IFR/WAAS" (e.g. TSO-C145c type) GPS "meets performance of" type requirements.

On Wednesday, February 11, 2015 at 7:00:42 AM UTC-8, wrote:
On Wednesday, February 11, 2015 at 12:39:47 AM UTC-6, jfitch wrote:
On Tuesday, February 10, 2015 at 8:17:50 PM UTC-8, Bill T wrote:
Most GPS units in gliders may be WAAS compliant, but with the previous language they were not approved to provide adsb out because they do not have the TSO Certification.
BillT

It appears in the new rules that it only has to meet the performance requirements. Furthermore the wording would suggest it is up to the installer to decide that it does until the FAA indicates otherwise? Which is reversed from TSO. Almost any GPS engine is WAAS compliant now. But I don't know what else is involved in meeting the 'performance requirement'. It seems like there is hope though, given that the spec was written while vacuum tubes were still in common use.

I'm sure Darryl will jump in at any moment and set me straight.

More on the subject this morning on the AVweb website:
http://www.avweb.com/avwebflash/news...e223533-1.html

I'm also eager to see what Darryl will make of this.

I think on one hand AV Web may overstates this, but on the other hand they are partially correct and mostly in the sense where this can get used as a shell game. e.g. manufacturers sometimes produce a TSO'ed device and a non-TSO'ed equivalent device and differentiate the two based on price even though they have little difference in actual manufacturing cost. And they sell the two devices to different markets, e.g. experimental vs. IFR aircraft (and where installers in some cases may erroneously believe they absolutely require to have a TSO'ed device when they may not).

In this case I don't expect this will actually significantly change any ADS-B Out costs in the USA not for some time. For example it is still a market where very few vendors can manufacturer any ADS-B Out device or GPS receiver that ... meets performance requirements of.. any TSO. Maybe not until vendors start producing an ADS-B Out devices with integrated GPS sources do I expect to see an ADS-B Out price drop. And prices will come down in general as 2020 approaches and people actually feel compelled to start installing anything (again gliders are exempt from most of the carriage requirements).. In which case I would not be surprised if manufacturers avoid formal TSOs and utilize the ...meets performance parts say at least for the internal GPS. And I would not be surprised if some vendors keep playing pricing shell games.