Sam this should answer your question 
link is at the bottom of the page
Phase 3: Performance Assessment
Performance assessment is the ATOS function that helps ensure operational safety. During your demonstration events, inspectors use the Element Performance Inspection (EPI) data collection tool to collect information that will be used by the Certification Project Manager (CPM) to affirm that your process design is being followed and that it produces the intended results.
During the Performance Assessment phase, you must:
Confirm your operational readiness for this phase by conducting an internal safety assessment of your operating systems, using your company�s audit procedures and documentation. After you ensure that all concerns found during the internal safety assessment are successfully addressed, you submit the results of the audit to the CPM.
Complete an aircraft conformity evaluation as described in FAA Order 8900.1 Volume 10 Chapter 6 Section 3. The purpose of an aircraft conformity inspection is to verify that your aircraft conforms to its type design and is in a condition for safe operation. Your role is to:
Notify the CPM of aircraft availability at least 10 working days prior to the proposed aircraft evaluation and forward the completed aircraft configuration control job aid (or equivalent) and aircraft information form to the CPM for the aircraft conformity evaluation.
Submit a letter of corrections to the CPM if there are discrepancies found during the conformity evaluation. The FAA must confirm that you have corrected discrepancies before proving tests are conducted.
Update the schedule of events, if required.
Refer to CPD step 3.4 and the Aircraft Document Requirements List, Figure 10-67, in Order 8900.1 Volume 10, Chapter 6, Section 2.
Prepare for the demonstration of your proposed operation. Your role is to:
Submit plans for a demonstration emergency evacuation, ditching, and proving test.
Submit a request for a letter of authorization (LOA), in accordance with part 119.33(c), for demonstrating appropriate operations under part 121. Make this request at least 10 business days before any aircraft flight demonstration.
Submit draft Operations Specifications.
Complete tabletop exercises. Refer to paragraph 10-440 in FAA Order 8900.1 Volume 10, Chapter 6, Section 2. The purpose of this step is for the FAA to determine if your system processes and personnel perform at a level that justifies conducting proving tests. Your role is to:
Conduct the tabletop exercise with the certification project team and discuss the results of each scenario.
Make corrections to your system design and/or correct personnel performance issues before beginning proving tests.
Conduct evacuation/ditching demonstrations, as required. Refer to CPD Step 3.5 in FAA Order 8900.1 Volume 10, Chapter 6, Section 2.
Conduct proving tests. Proving tests begin only after all Gate III requirements are met. Refer to paragraph 10-441 in FAA Order 8900.1 Volume 10, Chapter 6, Section 2.
FAA team members will report their observations during these activities on the Element Performance Inspection (EPI) data collection tool. The CPM will analyze that data and make an assessment about the performance of an air carrier system. In the past we focused on finding what was wrong with the way the system was performing; the focus now is on what is right and what is working well. We will continue to identify deficiencies; but we are assuming that the system process, if it is well-designed, should be performing the way it was intended and producing the desired result.
There are four categories of �performance affirmed.� See Table 10-4 of Order 8900.1 Volume 10 Chapter 2 Section 10. The CPM must be able to affirm the performance of each applicable Element in one of these categories before you can move to Phase 4 � Administrative Functions.
Phase 3 ends after the successful completion of the proving tests.
https://www.faa.gov/about/initiatives/atos/ai...r/phase_3/
link is at the bottom of the page Phase 3: Performance Assessment
Performance assessment is the ATOS function that helps ensure operational safety. During your demonstration events, inspectors use the Element Performance Inspection (EPI) data collection tool to collect information that will be used by the Certification Project Manager (CPM) to affirm that your process design is being followed and that it produces the intended results.
During the Performance Assessment phase, you must:
Confirm your operational readiness for this phase by conducting an internal safety assessment of your operating systems, using your company�s audit procedures and documentation. After you ensure that all concerns found during the internal safety assessment are successfully addressed, you submit the results of the audit to the CPM.
Complete an aircraft conformity evaluation as described in FAA Order 8900.1 Volume 10 Chapter 6 Section 3. The purpose of an aircraft conformity inspection is to verify that your aircraft conforms to its type design and is in a condition for safe operation. Your role is to:
Notify the CPM of aircraft availability at least 10 working days prior to the proposed aircraft evaluation and forward the completed aircraft configuration control job aid (or equivalent) and aircraft information form to the CPM for the aircraft conformity evaluation.
Submit a letter of corrections to the CPM if there are discrepancies found during the conformity evaluation. The FAA must confirm that you have corrected discrepancies before proving tests are conducted.
Update the schedule of events, if required.
Refer to CPD step 3.4 and the Aircraft Document Requirements List, Figure 10-67, in Order 8900.1 Volume 10, Chapter 6, Section 2.
Prepare for the demonstration of your proposed operation. Your role is to:
Submit plans for a demonstration emergency evacuation, ditching, and proving test.
Submit a request for a letter of authorization (LOA), in accordance with part 119.33(c), for demonstrating appropriate operations under part 121. Make this request at least 10 business days before any aircraft flight demonstration.
Submit draft Operations Specifications.
Complete tabletop exercises. Refer to paragraph 10-440 in FAA Order 8900.1 Volume 10, Chapter 6, Section 2. The purpose of this step is for the FAA to determine if your system processes and personnel perform at a level that justifies conducting proving tests. Your role is to:
Conduct the tabletop exercise with the certification project team and discuss the results of each scenario.
Make corrections to your system design and/or correct personnel performance issues before beginning proving tests.
Conduct evacuation/ditching demonstrations, as required. Refer to CPD Step 3.5 in FAA Order 8900.1 Volume 10, Chapter 6, Section 2.
Conduct proving tests. Proving tests begin only after all Gate III requirements are met. Refer to paragraph 10-441 in FAA Order 8900.1 Volume 10, Chapter 6, Section 2.
FAA team members will report their observations during these activities on the Element Performance Inspection (EPI) data collection tool. The CPM will analyze that data and make an assessment about the performance of an air carrier system. In the past we focused on finding what was wrong with the way the system was performing; the focus now is on what is right and what is working well. We will continue to identify deficiencies; but we are assuming that the system process, if it is well-designed, should be performing the way it was intended and producing the desired result.
There are four categories of �performance affirmed.� See Table 10-4 of Order 8900.1 Volume 10 Chapter 2 Section 10. The CPM must be able to affirm the performance of each applicable Element in one of these categories before you can move to Phase 4 � Administrative Functions.
Phase 3 ends after the successful completion of the proving tests.
https://www.faa.gov/about/initiatives/atos/ai...r/phase_3/
