RTCA/DO-297 and Technical Standard Order-C153, addresses a somewhat similar situation for integrated modular avionics (IMA). But, navigation and non-navigation avionics equipment that incorporate GNSS receiver circuit card assemblies are not an IMA. Therefore, the IMA guidance is not applicable.
(b) However, the FAA recognizes that GNSS receiver circuit card assemblies are more than “component parts” and fundamentally provide the GNSS sensor functional capability. In essence, the only difference between a complete GNSS sensor unit and a receiver circuit card assembly is the sensor unit includes a power supply and enclosure shielding. But this difference is significant relative to the performance tests in the minimum operational performance standard (MOPS) specified by the GNSS TSOs. The concern is that a bare receiver circuit card assembly could pass the MOPS performance testing in isolation, but not maintain that performance when integrated into another device where it might be exposed to significant radio frequency interference from other circuit card assemblies or devices. The FAA has created three new TSOs to address this concern and provide certification credit for the functional capabilities in GNSS receiver circuit card assemblies. But the GNSS receiver circuit card assembly’s end-user must repeat selected MOPS performance tests with the circuit card assembly installed in the end-use equipment and apply for the applicable GNSS sensor unit TSO (see paragraph 3-5).
i. Incorporating Step-down Fixes in Navigation Databases.
(1) Question: The latest ARINC 424 format has fields for both named and un named step-down fixes. Is it acceptable for equipment manufacturers to include approach procedure step-down fixes in the navigation database; particularly when LPV capability is included?
(2) Answer: Yes. But ARINC 424 is not a TSO-specified standard, so there is no “requirement” to include step-down fixes or use all the fields. Having step-down fixes in the navigation database can present challenges for the airworthiness approval when LPV capability is included since step-down fixes are not applicable to LPV and the LPV requirements are designed to mimic an instrument landing system (ILS). The airworthiness applicant must ensure there is no confusing or disparate information presented to flight crews due to the cockpit arrangement. This can be a significant issue in legacy cockpits that have limited display capabilities. See paragraph 12-8 for guidance when including step-down fixes in the navigation database.
j. Using RTCA Inc. document (RTCA)/(DO)-178C Software Considerations in Airborne Systems and Equipment Certification, dated December 13, 2011.
(1) Question: Is it acceptable for equipment manufacturers to use RTCA/DO-178C in lieu of RTCA/DO-178B?
(2) Answer: Yes. In the U.S. it is acceptable for software development to use revision ‘C’ for TSOs that specify revision ‘B’ thru the deviation process. The project ACOs may approve deviation requests to use revision ‘C’ in lieu of revision ‘B’ without Headquarters 8
coordination. Refer to AC 20-115C for additional guidance on software qualification, including re-using software qualified to previous RTCA/DO-178 revisions.
Chapter 2. Technical Standard Order Authorization (TSOA) and Airworthiness Approval Considerations - General.
2-1. Guidance for TSOA/Letter of Design Approval (LODA) and Airworthiness Approvals.
Title 14 CFR part 21; subparts D, E, and O provide the regulatory basis defining changes to TC (major/minor changes to aircraft type design), STC, and TSOAs. The regulations and TSOs can be found at: http://rgl.faa.gov. This chapter provides general guidance on TSOA/LODA and airworthiness approval considerations specific to positioning and navigation equipment.
2-2. TSOA.
a. Several TSOs are available for positioning and navigation-related equipment and components (see appendix 10 of this AC). New TSOs will be written to address modernized GPS and other GNSSs once appropriate equipment standards are in place. It is benefi cial to
involve the ACO (both engineers and flight test pilots) in equipment evaluations as early as
possible for four primary reasons:
(1) Obtaining a TSOA/LODA does not ensure that the equipment will satisfy all of the applicable operational requirements and/or airworthiness regulations when it is installed.
(2) Positioning and navigation equipment has become increasingly more complex and workload intensive with no standardized pilot interface. The human factors evaluation of the equipment can be subjective.
(3) There is no one, single standard for interfacing positioning and navigation equipment to other equipment on-board the aircraft such as displays, autopilots, and terrain
warning systems. Positioning and navigation equipment manufacturers should develop compatibility data relative to other equipment for inclusion within the installation manual.
(4) The installed intended function for the equipment needs to be compatible with the original design for the system, including software and hardware design assurance levels and data process assurance levels. For example: a decision by the positioning and navigation equipment manufacturer to develop system software to RTCA/DO-178B Level C, may limit installation eligibility if that equipment contributes to failure conditions of other systems that perform critical functions to a higher software design assurance level.
Note: AC 20-115C provides guidance on using RTCA/DO-178C including re-using software qualified to previous RTCA/DO-178 revisions.
b. It is recommended that the positioning and navigation equipment manufacturer elect to obtain an STC for equipment installation concurrent with obtaining the TSOA/LODA. This has proven to be an effective method to aid installations.
Note: Any applicant may apply for an equipment installation STC. It is not this paragraph’s intent to limit 10
positioning and navigation installation STCs solely to avionics manufacturers.
c. The installation manual and other data approved during the TSOA process can be used as a source of approved data to support an installation airworthiness compliance finding provided the data is applicable to the installation airworthiness requirements (see AC 21-50 (latest revision), Installation of TSOA Articles and LODA Appliances).
2-3. STC-Approved Model List (AML).
a. All STC applicants are encouraged to use an AML for aircraft makes/models (including 14 CFR parts 23, 25, 27, and 29 aircraft) with similar characteristics and compatible equipment configurations to streamline the approval of subsequent installations. Applicants and ACOs need to contact the applicable directorate for specific policy and guidance information on obtaining an STC-AML.
b. Using the STC-AML method can simplify follow-on installations for makes/models on the AML. T he installer needs access to the STC approved data; apply the approved data;
and comply with the detailed installation instructions. The installer then needs only complete FAA Form 337, Major Repair and Alteration (Airframe, Powerplant, Propeller, Appliance), identifying the nature of the change to return the aircraft to service (see AC 43.9-1 (latest revision), Instructions for Completion of FAA Form 337).
c. GPS and GPS/SBAS equipment airworthiness approval is not considered novel or unusual per 14 CFR 21.16 and applicants can use designees during the STC process.
2-4. Type Certificate.
Positioning and navigation equipment manufacturers are also encouraged to work with TC holders. This has also proven to be an effective method to aid installations.
Chapter 3. TSO Authorization.
3-1. TSO-C196(AR).
a. TSO-C196(AR), Airborne Supplemental Navigation Sensors for Global Positioning System Equipment Using Aircraft-Based Augmentation, defines an acceptable standard for GPS equipment without ground-based or space-based augmentations. The TSO has been updated to revision ‘b’ for harmonization with TSO-C129a’s cancellation and for TSO-C206 circuit card assemblies. TSO-C196(AR) is intended as the aircraft-based augmentation GPS sensor standard for TSOA/LODA applicants. TSO-C196(AR) equipment has a performance limitation that requires other positioning and navigation systems appropriate to the operation on-board the aircraft.
Note: TSO-C129a has been cancelled, but this does not affect equipment with an existing TSOA/LODA (see paragraph 3-1.c).
b. TSO-C196(AR) defines GPS sensor equipment that incorporates many processing improvements found in the GPS/SBAS equipment MOPS; but, without the GPS/SBAS requirements. Two improvement examples are: a requirement for the receiver to properly account for satellite range error if it is reflected in the User Range Accuracy index (commonly referred to as being “Selective Availability aware”), and requirements to ensure performance is not degraded due to an increasing radio frequency noise environment as other satellite systems become available.
(1) TSOA/LODA applicants may wish to have a previously approved TSO-C145b (or later revision), Airborne Navigation Sensors Using the Global Positioning System (GPS) Augmented by the Wide Area Augmentation System (WAAS), sensor approved as a TSO-C196b sensor. It is acceptable for TSO -C196b applicants to take certification credit by re-using data developed during a previous revision ‘b’ or later TSO-C145 TSOA/LODA approval. RTCA/DO-316, Minimum Operational Performance Standards for Global Positioning System/Aircraft-Based Augmentation System Airborne Equipment, dated April 14, 2009, implemented by TSO-C196(AR) was developed from RTCA/DO-229D, Minimum Operational Performance Standards for Global Positioning System/Wide Area Augmentation System (GPS/WAAS) Airborne Equipment, dated December 3, 2006, implemented by TSO C145b/c (revision ‘d’ implements RTCA/DO-229D, Change 1). Both RTCA/DO-229D and RTCA/DO-229D, Change 1 meets or exceeds the performance requirements for TSO-C196b.
The original RTCA/DO-178B or ‘C’ documentation can be re-used if there are no software changes.
(2) Applicants seeking a TSO-C196b TSOA/LODA based on a previously approved revision ‘b’ or later TSO-C145 sensor must maintain separate part numbers for each unit. It is not acceptable to have both a TSO-C145(AR) and TSO-C196(AR) TSOA/LODA simultaneously on the same article (see paragraph 3-6.b(4)).
Note: Maintaining separate part numbers might only require different software part numbers.
(3) It is acceptable for TSOA/LODA applicants with revision ‘b’ or later TSO-C145 sensors to simply disable the GPS/SBAS tracking loops in their equipment to apply for a TSO-C196b TSOA/LODA. The applicant will need to su pply substantiation that the SBAS tracking loops are permanently disabled along with the data from their revision ‘b’ or later TSO-C145 TSOA/LODA.
(4) TSOA/LODA applicants with TSO-C145a sensors will need to show requirements traceability between RTCA/DO-229C and RTCA/DO-316 along with data applicability to receive appropriate certification credit. In particular, applicants will need to show compliance to all RTCA/DO-316 requirements not addressed in RTCA/DO-229C, and requirements that are more stringent such as enroute/terminal mode accuracy and the broadband external interference noise environment.
c. TSO-C129a was cancelled effective October 21, 2011, but there is no plan to withdraw TSO-C129(AR) authorizations. TSO-C129a cancellation will not affect existing authorizations. Manufacturers can continue production according to their existing TSO-C129(AR) TSOA/LODA. Additionally, the equipment is still eligible for installation according to existing airworthiness approvals and is eligible to receive new airworthiness approvals.
(1) No new TSO-C129a TSOAs/LODAs will be granted.
(2) Major changes to an existing TSO-C129a equipment design will require a new application according to 14 CFR 21.619(b) for either TSO-C145d, TSO-C146d or TSO C196b.
3-2. TSO-C145(AR)/C146(AR).
a. TSO-C145d, Airborne Navigation Sensors Using the Global Positioning System (GPS) Augmented by the Satellite-Based Augmentation System (SBAS) and TSO-C146d, Stand- Alone Airborne Navigation Equipment Using the Global Positioning System (GPS) Augmented by the Satellite Based Augmentation System (SBAS) define an acceptable standard for GPS/SBAS equipment. There is no equipment performance limitation for GPS/SBAS equipped aircraft to have other positioning and navigation systems on-board.
Note: Refer to the appropriate operating rules and
operational guidance documents for equipage
requirements.
b. RTCA/DO-229D referenced by the GPS/SBAS TSOs will remain as the MOPS for single-frequency GPS/SBAS equipment. Future multi-frequency/multi-constellation equipment will have a separate MOPS and TSO.
c. There is no plan to withdraw authorizations to the earlier TSO revisions, so manufacturers of TSO-C145/C146 revision ‘a’ through ‘c’ equipment can continue production according to their TSOA/LODA; and the equipment is still eligible for installation in accordance with the guidance in this AC.
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d. The difference between revisions ‘b’ and ‘c’ to the GPS/SBAS TSOs is eliminating a 3 decibel (dB) broadband intra-system noise credit for operational Class 1 and Class 2 equipment in RTCA/DO-229D. TSO-C145b/C146b operational Class 3 and Class 4 equipment fully complies with the requirements in TSO-C145c/C146c and is automatically eligible for a revision ‘c’ authorization, i.e., no further evaluation is necessary.
e. The difference between revisions ‘c’ and ‘d’ to the GPS/SBAS TSOs is:
recognizing TSO-C204/C205 circuit card assemblies; and using Change 1 to RTCA/DO-229D.
f. TSO-C145b/C146b operational Class 1 and Class 2 equipment that did not claim the 3dB noise credit is also eligible for a revision ‘c’ authorization. The TSOA/LODA holder only needs to provide substantiation that they did not take the noise credit during the original certification.
g. Displays or navigation computers (such as FMSs) may receive a TSO-C146d Class 1, 2, or 3 (functional Class Gamma) incomplete TSOA/LODA provided they meet the applicable Class Gamma requirements in RTCA/DO-229D and are linked by part number to compatible TSO-C145(AR) sensors in the TSO application documentation. This is an effective method to aid GPS/SBAS installation approvals to make a complete system (sensor, navigation computer, display) at the aircraft level.
Note: See paragraph 3-4 for additional information on FMS incomplete TSO-C146c Class Gamma TSOA/LODAs and Class Delta-4 FMS implementations.
3-3. TSO-C161a/C162a.
a. TSO-C161a, Ground Based Augmentation System Positioning and Navigation Equipment, defines an acceptable standard for GPS/GBAS equipment that provides precision approach capability and position/velocity/time (PVT) information to navigation management equipment. TSO-C162a, Ground Based Augmentation System Very High Frequency Data Broadcast Equipment, defines an acceptable standard for GPS/GBAS equipment designed to receive a very high frequency data broadcast (VDB) and output the VDB messages to GPS/GBAS positioning and navigation equipment.
b. TSO-C161a and TSO-C162a invoke only the requirements in RTCA/DO-253C, Minimum Operational Performance Standards for GPS Local Area Augmentation System Airborne Equipment, dated December 16, 2008, that are needed to support Category I (CAT I) precision approach and, if applicable, the GPS/GBAS positioning service. The equipment may output PVT based on either the GPS/GBAS positioning service, or PVT from GPS or GPS/SBAS. The PVT based on GPS/GBAS is only available when the ground station supports the positioning service. TSO-C161a equipment must also obtain a TSO-C145d, TSO-C146d, or TSO-C196b TSOA. Requirements in RTCA/DO-253C needed to support precision approaches beyond CAT I are not invoked in these TSOs as these requirements have not been validated.
Once validated, the FAA will either publish TSO revisions or new TSOs.
c. TSO-C161a and TSO-C162a compliant equipment does not address any RNAV capability. A partial missed approach capability is an option in the GPS/GBAS equipment but 14
is not required (see note). RNAV capability for the initial, intermediate, and missed approach segments must be addressed during the aircraft GPS/GBAS integration (see paragraph 15-9.1).
Note: Equipment meeting the RTCA/DO-253C precision and navigation (PAN) requirements can include an optional capability to provide guidance for the initial, straight-out portion of the missed approach segment. However, this capability doesn’t provide guidance for the complete missed approach segment.
3-4. TSO-C115(AR).
a. TSO-C115d, Required Navigation Performance (RNP) Equipment Using Multi- Sensor Inputs defines an acceptable certification standard for obtaining design and production approval for multi-sensor navigation systems or FMSs integrating data from multiple navigation sensors. There is no plan to withdraw TSO authorizations granted under earlier TSO-C115 revisions. Manufacturers of earlier TSO-C115 revisions can continue production according to their TSOA/LODA; and the equipment is still eligible for installation in accordance with the guidance in this AC. However, integrating GNSS into TSO-C115/C115a multi-sensor navigation equipment is considered a major change and requires an application for a TSO-C115dTSOA/LODA.
(1) TSO-C115b only addressed TSO-C129 Class B and C sensors because it was published prior to TSO-C129a, TSO-C145(AR), TSO-C161(AR), and TSO-C196(AR). It is acceptable to integrate any GNSS sensor with TSO-C115b equipment.
Note: The multi-sensor navigation system or FMS must comply with TSO-C115 revision ‘b’ (or a later revision) when integrating GNSS sensors if TSO-C115 is the approval basis. It is not acceptable to use systems certified to earlier TSO-C115 revisions for GNSS sensor integration (see paragraph 3-6.b(1)).
(2) Localizer performance without vertical guidance (LP)/localizer performance with vertical guidance (LPV) is considered a severe major/hazardous failure condition for misleading information (see paragraph 12-2.a). Equipment manufacturers may design FMSs for either a TSO-C146d Class Gamma-3, or Class Delta-4 architecture when integrating LP/LPV capability.
(a) A TSO-C115b (or later revision) FMS designed as a Class Gamma-3 architecture typically has level B software for the LP/LPV processing functions. It is acceptable to have the GPS/SBAS capability and level B software partitioned from other functions in the FMS. See paragraph 3-4.b for additional information on incomplete TSO-C146c Class Gamma TSOA/LODAs.
(b) TSO-C146d Class Delta-4 provides an ILS look-alike for LP/LPV final approach segment-only capability. A TSO-C115b (or later revision) FMS designed for a Class Delta-4 architecture does not process LP/LPV inputs; does not output LP/LPV deviations, path 15
construction, alerts, etc.; and, does not require the FMS to have a TSO-C146d TSOA/LODA.
The aircraft integration must include a GPS/SBAS sensor that has a TSO-C146d Class Delta-4 TSOA/LODA. See paragraph 3-4.c for additional information on Class Delta-4 implementations.
b. FMS manufacturers may add an incomplete TSO-C146d TSOA/LODA to FMSs certified to TSO-C115b (or later revision). An appropriate operational class incomplete TSO-C146d Class Gamma TSOA/LODA provides an established means for the installed FMS to demonstrate navigation computer compliance as a GPS/SBAS system.
Note 1: FMSs that do not meet the applicable RTCA/DO-229D Class Gamma performance requirements can still receive PVT inputs from a TSO C145(AR) sensor and apply them consistent with their existing approvals. Using a TSO-C145(AR) sensor can remove certain performance limitations associated with a TSO-C129(AR) sensor (see paragraphs 5-5.2.b and
5-5.2.c).
Note 2: There is significant overlap in requirements between TSO-C146d Class Gamma implementation of RTCA/DO-229D and TSO-C115d implementation of RTCA/DO-283B Minimum Operational Performance Standards for Required Navigation Performance for Area Navigation requirements. Where requirements overlap exists it is acceptable to re-use compliance information from RTCA/DO-229D as the method of demonstrating RTCA/DO-283B compliance. However, applicants remain responsible to ensure all RTCA/DO-283B requirements are satisfied.
Note 3: TSO-C146d Class Gamma has alert limits for navigation system error (NSE) at 1 x RNP value and assumes a fixed, manual flight technical error (FTE). The TSO-C146d Class Gamma FTE assumption and NSE alert meets the 2 x RNP TSE alerting requirement for RNP operations. TSO-C115d does not assume a fixed FTE value which allows applicants to trade off FTE and NSE when meeting the 2 x RNP TSE alerting requirement.
(1) TSO-C146d will take precedence when adding an incomplete TSO-C146d Class Gamma TSOA/LODA to an FMS with an existing TSO-C115b or later TSOA/LODA if there are any conflicts between the two TSOs.
(2) TSO-C115d requires the FMS meet the minimum performance standard documentation and qualification requirements for Class A or Class B specified in sections 2.1 and 2.2 of RTCA/DO-283B. Class A includes full VNAV and advanced RNP capability while Class B includes only 2-dimensional RNP navigation functions. Class B applicants that wish to 16
--- ---- include baro-VNAV capability or receive advanced RNP recognition must comply with the appropriate RTCA/DO-283B requirements. See RTCA/DO-283B, Table 2-13 for a complete list of the required Class A and Class B functions. The baro-VNAV guidance in this AC must be used when including baro-VNAV for approach capability. See appendix 3 for guidance on advanced RNP recognition.
(3) FMSs may qualify as TSO-C146d Class Gamma navigation computer systems when receiving inputs from a TSO-C145d Class Beta sensor. An incomplete TSO C146d Class Gamma approval (Gamma-2 or -3 as appropriate) can be added to the TSO-C115b (or later revision) approval, or replace the TSO-C129(AR) approval if one exists, to provide GPS/SBAS-based VNAV approach capability. Class Gamma -1 can be used for FMSs that don’t intend to process GPS/SBAS vertical deviations.
Note: Several issues must be considered for FMSs integrating both baro-VNAV and GPS/SBAS to provide LNAV/VNAV capability. For example; unambiguous navigation source and approach service level annunciation, discontinuities or jumps when switching from baro-VNAV to GPS/SBAS vertical guidance, and prioritizing when to use which source (see paragraphs
6-3.b, 16-2.a, and 18-5).
c. For Class Delta-4 architectures, FMSs in typical federated avionics architectures do not need an incomplete TSO-C146d Class Delta-4 TSOA/LODA for LPV capability since the FMS does not provide or process flight path deviation data or GPS/SBAS alerting functions during the final approach segment. The complete system (sensor with Class Delta-4 TSOA/LODA, level B path, and display) will be confirmed at the time of installation. See paragraph 15-2.a regarding displays and path for legacy aircraft retrofit installations previously certified with ILS.
(1) It is acceptable for the Class Delta-4 sensor to reside within the FMS itself provided the LP/LPV outputs are not processed or altered by the FMS (similar to an ILS).
(2) The FMS may provide an interface for pilot control of the Class Delta-4 equipment (such as selecting the approach) and may host the Final Approach Segment (FAS) database for input to the Class Delta-4 equipment. The Class Delta-4 TSOA/LODA holder must list the specific compatible FMS(s) or provide a detailed interface description to establish FMS compatibility in the installation manual.
(3) At the aircraft level, Class Delta-4 implementations depend upon the entire path for the guidance deviations complying with a severe major/hazardous failure condition in modern aircraft with digital data busses. See paragraph 15-2.a regarding displays and path for legacy aircraft retrofit installations previously certified with ILS.
(4) Non-federated FMS architectures, such as integrated modular avionics, may have the Class Delta-4 LP/LPV final approach segment capability residing within the FMS functions or components. The applicable modules for these FMSs will need a TSO-C146d Class Delta-4 TSOA/LODA and appropriate software level for the Class Delta-4 performance 17
requirements listed in RTCA/DO-229D that they provide.
Note: It is also acceptable for applicants with non-federated FMS architectures to consider pursuing incomplete TSO-C146d Class Gamma approval for the navigation computer functions/components.
(5) An FMS that is part of an aircraft-level TSO-C146d Class Delta-4 integration normally provides the RNP capability for the initial and intermediate approach segments to place the aircraft in proper position for the Class Delta-4 GPS/SBAS equipment to conduct the LP/LPV final approach segment. The FMS also provides the RNP capability for the missed approach segment.
Note: RNP capability for the initial, intermediate, and missed approach segments can be accomplished by the FMS according to its TSO-C115b (or later revision) or other GNSS TSO approval. However, the FMS will be limited to its approved functions per those TSOs or as modified if receiving PVT inputs from a TSO-C145(AR) sensor (see paragraphs 5-5.2.b and 5-5.2.c).
d. Multi-sensor systems must also comply with the appropriate TSO requirements for the individual sensors that are integrated. For example, if distance measuring equipment (DME) is integrated, then the system must also comply with TSO-C66c, Distance Measuring Equipment (DME) Operating Within the Radio Frequency Range of 960 to 1215 Megahertz, for DME equipment. Refer to AC 90-100 (latest revision) , U.S. Terminal and Enroute Area Navigation (RNAV) Operations, for operational approval of terminal and enroute area navigation systems for use in the U.S. national airspace system.
3-5. TSO-C204/C205/C206.
a. The FAA created three new TSOs to recognize the functional capability of GNSS sensor circuit card assemblies and enable end-use manufacturers to incorporate these devices for navigation and non-navigation uses. The intent is to ease the GNSS sensor TSO burden for end-use equipment manufacturers; particularly for non-navigation equipment such as ADS-B or TAWS. But FMS, multi-mode receiver, or other navigation equipment manufacturers could also benefit from these TSOs.
b. The three circuit card assembly TSOs are matched to the three existing GNSS sensor TSOs as follows:
• TSO-C204 to TSO-C145d
• TSO-C205 to TSO-C146d Class Delta-4
• TSO-C206 to TSO-C196b 18
--- Note: TSO-C205 is not appropriate for TSO-C146d Class Gamma functionality since Class Gamma is a combined sensor/navigation computer/display. However, TSO-C204 can be used for the sensor portion of a Class Gamma unit similar to using TSO-C204 in an FMS or multi-mode receiver.
c. Appendix 1 in TSO-C145d/C146d/C196b contains information on the MOPS performance tests the end-use manufacturer must re-accomplish to receive the appropriate TSOA. The end-use manufacturer must mark their equipment with the appropriate GNSS sensor TSO and assumes full responsibility for the GNSS sensor TSOA per the 14 CFR Part 21 Subpart O regulations.
d. The purpose of the new TSOs is to provide certification credit to the end-use equipment manufacturer for the following items performed by the circuit card assembly manufacturer:
• compliance with the requisite MOPS section 2 requirements,
• hardware/software development,
• failure condition classification, and;
• partial MOPS performance testing.
However, the circuit card assembly TSOs have limitations requiring the end-use manufacturer to apply for the latest revision of TSO-C145, TSO-C146 Class Delta-4, or TSO-C196, consistent with the circuit card assembly TSO.
e. The end-use equipment manufacturer receives credit for the items in paragraph 3-5.d by virtue of the circuit card assembly TSO. To receive a GNSS sensor TSOA the end-use equipment manufacturer data submittal is:
(1) The TSO on the circuit card assembly;
(2) The repeated MOPS performance testing according to the GNSS TSO appendix 1;
(3) All other documentation associated with the GNSS sensor TSO, including environmental testing.
3-6. Multiple TSO Authorizations.
a. Multiple TSO authorizations may be granted for equipment that accomplishes multiple functions. However, the number of TSO markings on positioning and navigation equipment should be minimized to avoid confusion during installation and approval.
b. The following combinations of TSO authorizations must not be granted, as the TSOs either contradict each other or are superfluous to a TSO with broader scope: