FAA suspends approval of NavWorx ADS-B units over GPS chip inspections

November 22, 2016  - By
Image: GPS World

The U.S. Department of Transportation’s Federal Aviation Administration today issued an emergency order suspending the authorization NavWorx Inc. uses to manufacture certain Automatic Dependent Surveillance-Broadcast (ADS-B) navigation units.

The suspension order was issued after NavWorx declined on repeated occasions to allow FAA personnel to conduct the required inspections. The suspension is immediate and will remain in effect until NavWorx consents to the inspections and demonstrates compliance with FAA standards.

ADS-B units, when properly manufactured and operated, help to improve the safety and efficiency of aircraft operations.

The authorization, known as a Technical Standard Order Authorization (TSOA), enables suppliers to produce components for use on aircraft after proving that each component meets FAA standards. Federal regulations set forth FAA’s authority to inspect suppliers’ quality systems, facilities, technical data, and products to determine whether they meet safety standards. These regulations also provide that FAA may witness any tests necessary to determine a product’s compliance.

The FAA is concerned that two versions of the company’s ADS600-B units, carrying part numbers 200-0012 and 200-0013, may contain an internal GPS chip that does not meet the FAA’s minimum performance standards for transmitting an aircraft’s accurate location.

On June 29, the FAA requested to inspect NavWorx’s facility to determine the specific GPS unit and software installed in part numbers 200-0012 and 200-0013, and if the units are marked correctly. NavWorx informed the inspector that he would not be allowed inside the company’s facility. During subsequent correspondence, NavWorx agreed to allow an Aug. 31 inspection but then denied access when FAA inspectors arrived.

NavWorx later agreed to allow inspectors into the facility on Nov. 21 but they were again denied access.

Due to the company’s unwillingness to comply with these requirements, the FAA has determined that NavWorx’s continued use of its FAA authorization is contrary to the interests of safety in air commerce. During the suspension, NavWorx may not mark or otherwise indicate that its ADS600-B units meet FAA standards.

NavWorx Responds

Navworx president Bill Moffit posted the following on the company website:

“I first want to thank all of you for your patience during this unfortunate and unprecedented situation. Contrary to what you may surmise from emails and proposed actions, I want to ensure everyone that we are diligently working on the solution to resolve this situation in a timely matter. NavWorx values the commitment you have placed in us by purchasing our products and strives to honor that commitment that you have entrusted with us.

“Currently we are waiting on the resolution of the AD [Airworthiness Directive] on or about December 20th. Based on the final AD, the AD may be rescinded, or the AD may be modified to allow for just previously approved GPS sources. If the FAA does not allow the use of the internal GPS, then we will offer the ability to modify the products from the 200-0012 & 200-0013 part numbers to part numbers 200-0112 & 200-0113. The 200-0112 & 200-0113 part numbers are approved under the FAA Rebate program and are not the subject to the AD.

“As I hope you understand, the past few weeks our phone system has been overwhelmed by volume and we can imagine the frustration this may cause. Be assured we are here and working tirelessly to take care of you, our customer.

“Please check our web page weekly for updates and for our announcements which will detail our program to remedy this situation.

“For those that need immediate service, feel free to contact our support email at support@Navworx.com or contact our Distributor, Dallas Avionics, Inc Product Specialist, Scott C Edwards at 214-668-7466 or 800-527-2581.


“Bill Moffitt
“NavWorx Incorporated”

NavWorx also issued the following statement on Oct. 17:

Statement on FAA Proposal of AD

The FAA has proposed an AD for our model ADS600-B part number (P/N) 200-0012 and 200-0013 and Model ADS600-EP P/N 200-8013. The proposal is just that; a proposal. We disagree with the FAA’s position that the units supposedly communicate unreliable position information.

The FAA has never shared with us any instance of our units doing so, there is no support for this claim in the docket, and we are unaware of any unit doing so. In fact, for two and a half years the FAA had no problem with the ability of our units to correctly communicate the position of aircraft with the units.

Unfortunately, in January of 2016 the FAA would have cut off functionality of these units because they were broadcasting a SIL of 0. This action was the result of a March 2015 notice to deny TIS-B access to ADS-B units that were uncertified and broadcasting with a SDA of 0. The units subject to the proposed AD are neither uncertified nor do they broadcast with a SDA of 0.

To insure continued access to TIS-B data we implemented a minor change so the units would broadcast a SIL of 3, which our testing had confirmed was appropriate, allowing them to continue to be identified for TIS-B purposes. The proposed AD would deny these units access to TIS-B data.

We intend to file comments on the proposal and would encourage you to do likewise regarding your experience with our units. In the meantime we continue to work with the FAA to resolve our disagreements.

If you have comments on this AD or the FAA’s implementation of ADS-B, please contact Administrator Huerta or your congressman:

Contact: Administrator Huerta
Via: Max Slutsky, Special Advisor to the Administrator
email: Max.Slutsky@FAA.gov tel: 202-267-9869
Contact your Congressman: http://www.house.gov/representatives/find/

This is posted in Latest News, Transportation