TSO Qualifications | Page 2 | SkyGuardTWX Systems | Discussion Forum


Please consider registering

sp_LogInOut Log In sp_Registration Register

Register | Lost password?
Advanced Search

— Forum Scope —

— Match —

— Forum Options —

Minimum search word length is 3 characters - maximum search word length is 84 characters

No permission to create posts
TSO Qualifications
June 2, 2015
3:06 pm
SkyGuard Members

Forum Posts: 7
Member Since:
August 6, 2014
sp_UserOfflineSmall Offline

Well, I had a friendly call from the FAA telling me to either have my ADS-B out fixed or turn it off. The out is 100% fail and that is probably because the it is not broadcasting a Barometric Altitude. I explained that TSO certification was ongoing and was expected before the 2020 mandate, but it was explained that while the mandate wasn't until 2020 that there were regulations in effect requiring units in operation to meet the standards. Since mine was not I got a phone call.

I guess I will be turning my transmit off sooner than my planned GPS upgrade. My only hope is that there are enough units out there to keep the puck active in my flight area.

I thoughts are that many will be getting these phone calls over the next few weeks and months. I hope not but it sounds likt they set up a group to review the data printouts starting last November.

Bad news for all of us really.

June 3, 2015
9:24 pm
Don Houtz
Forum Posts: 24
Member Since:
June 16, 2014
sp_UserOfflineSmall Offline

I am aware of the FAA guy calling all ADS-B Transmitter customers and telling
then there is something wrong with their unit. This is not correct and this guy
does not know what he is doing or he is mis-informed by his management,
at least as far as the SkyGuardTWX units are concerned.
As I understand it, he has a list of 900 names and is working his way thru the phone
calls. Obviously we have not sold anywhere near 900 units, so he must be calling everyone
who has any possible (key word is Possible!) issue flagged with the FAA ADS-B compliance report.
The FAA has an ADS-B compliance report that many have requested the FAA run on their ADS-B Transmitter.
This report is comparing the transmitter output message results against the "requirements for
a certified transmitter". As you know, our units are not yet certified, so there will be some areas
that show up in RED highlighting the specific discrepancy. In our case, the 3 primary RED areas are:

- reporting GPS altitude rather than pressure altitude
- SDA set to 0
- SIL set to 0

Our original models transmit GPS altitude because in the ADS-B equipment specification (DO-282B), it clearly
states that the transmitter may transmit either GPS altitude, Pressure Altitude, or Both.
Since our units are currently "Portables", there was no FAA authorization to physically connect them
to a Mode C Transponder or a pressure altitude sensor. The FAA would not allow us to do this.
Therefore had no way to collect the Pressure Altitude value and had to report only the GPS altitude.
Once we achieve the TSO certification, these units can connect to a Mode C Transponder to get the pressure altitude.
Also, we recently introduced a new model that has the ability to wirelessly listen to a Mode C Transponder and acquire
the pressure altitude that way. Either way, the DO-282B specification for ADS-B equipment functionality states
that either can be used.

As far as SDA and SIL values, I will address them below:

FAA management is well aware of our Transceivers and has never told us they cannot be used.
The head guy in Washington for the FAA who is responsible for ADS-B equipment implementation
Is named Don Walker. I speak with him often and he knows the configuration of our units.
He also knows we are in process of completing the TSO certification. Per his direction,
As long as we set certain bits in the ADS-B transmitted message stating that our units are
Not yet certified, we are OK. These bits tell ATC not to rely on our transmitted signal
For aircraft separation. These bits are the SDA and SIL bits and we have to set both of these
To ‘0’ which is used by ATC to know that the transmitted message comes from an uncertified
ADS-B Transmitter. Once we achieve certification, we will change these bits to values that
Will indicate the unit is TSO’d.

Also, our Transceivers have been authorized by the FCC and we have a license that clearly
States we can turn them on and broadcast over the US airwaves. It does not matter whether
You have the SkyGuardTWX unit in your car, airplane, or sitting on your back porch, you have
The right to turn it on and begin broadcasting. As long as you treat the unit as a “portable”,
There is nothing the FAA can do to keep you from using it.

Don Houtz

June 4, 2015
12:37 am
SkyGuard Members

Forum Posts: 7
Member Since:
August 6, 2014
sp_UserOfflineSmall Offline


Is there any way to get Don Walker and this guy on the same page? I would be happy to forward his name and email address to you in an e-mail!!!!!

April 3, 2017
3:13 am
chris doyle
New Member
Forum Posts: 1
Member Since:
September 14, 2016
sp_UserOfflineSmall Offline

Any new information on TSO status? I bought my unit at Airventure 2016.

July 11, 2017
3:05 am
Forum Posts: 8
Member Since:
March 12, 2015
sp_UserOfflineSmall Offline

•Plan to meet FAA 2020 ADS-B OUT requirement once TSO-C154c certification has been completed

FAA stated that it wasn't that hard to get if you were actively trying.


No permission to create posts
Forum Timezone: UTC 0

Most Users Ever Online: 19

Currently Online:
1 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Top Posters:

PA-22: 11

johnwfranks: 8

jscott.planes: 7

OldPilot: 4

Jim Logajan: 4

zn105: 3

SouthEastLSAservices: 3

robmorgan1: 3

VIN2020: 3

Pazzopilot: 2

Member Stats:

Guest Posters: 0

Members: 102

Moderators: 11

Admins: 2

Forum Stats:

Groups: 1

Forums: 4

Topics: 31

Posts: 112

Newest Members:

Manny, glen sullivan, Ben, Jim B, Swashplate, Bob, Joe, Dale_1, Dale, HenryLumma

Moderators: marsolgp: 0, leydsmanw: 0, Allensilberman: 0, Zane: 0, rshannon: 0, Brian_Neiman: 0, tmyers: 7, PAUL WESTCOTT: 0, jnmarshall: 8, rocpilot: 0, greghughes: 0

Administrators: Zane: 0, Don Houtz: 24