SSN DRAFT SOW for FY25 Vessel-based UAS and Support Services.pdf

DEPARTMENT OF COMMERCE

National Oceanic Atmospheric Administration

Office of Atmospheric Research and Office of Marine and Aviation Operations

Statement of Work

UAS Science Flight Operations Supporting NOAA

National Marine Fisheries Service (NMFS) Marine Mammal Surveys

Date: November 4, 2024

DRAFT

for

SOURCES SOUGHT

NOTICE

Table of Contents

1.0 GENERAL INFORMATION 3

1.1 Introduction 3

1.2 Background 3

2.0 SUPPORT AND SERVICES 3

3.0 DEFINITIONS AND ACRONYMS 4

3.1 Contracting Officer (CO) 4

3.2 Contracting Officer’s Representative (COR) 4

3.3 Government Point-of-Contact (GPC) 4

3.4 Quality Assurance 4

3.5 Quality Control 4

3.6 Uncrewed Aircraft System (UAS) 4

3.7 Uncrewed Aircraft (UA) and Ground Control System (GCS) 4

3.8 Command and Control Link (C2) 4

3.9 Payload Communications Link 5

4.0 TECHNICAL CONTRACT REQUIREMENTS 5

4.1 Contract/Program Manager 5

4.2 Contractor Workforce Responsibility 5

4.3 Quality Assurance 5

4.4 Government Point of Contact for Quality Assurance 5

4.5 Government furnished equipment (GFE) 5

4.7 Performance of Contractor and/or Subcontractors 6

4.8 Scientific Data Rights 6

5.0 CLIN 0001 AND REQUIREMENTS – SUPPORT AND SERVICES 6

5.1 Task 1 - Integrate NOAA-selected Payloads onto UAS Platform and Demonstrate Shipboard Launch and Recovery from a Moving Vessel 7

5.2 Task 2 - Lease Aircraft Equipment and Operations Support for NOAA Vessel Pre-Mission Test Exercise 8

5.3 Task 3 - Lease Aircraft Equipment and Operations Support for NOAA Vessel Mission Involving NMFS Marine Mammal Surveys 9

6.0 PERIOD OF PERFORMANCE AND SCHEDULE 10

6.1 CLIN 0001 - Support and Services 10

7.0 DELIVERABLES 10

7.1 Deliverables CLIN 0001 10

8.0 PAYLOAD DESCRIPTIONS 11

8.1 High-resolution Nadir Imaging System (Sony ILX-LR1) 11

8.2 Full Motion Video Imaging System (Trillium HD55-VV) 11

1.0 GENERAL INFORMATION

1.1 Introduction

The purpose of this action is, in part, to provide for the use (via support and lease) of a hybrid, Vertical Take Off and Landing (VTOL) – Fixed Wing (FW) Uncrewed Aircraft System (UAS) capable of shipboard launch and recovery and collection of targeted science data that can be used to meet requirements for an upcoming NOAA National Marine Fisheries Service (NMFS) Test Exercise in April 2025 and Marine Mammal Survey Science Mission in July/August 2025 in the Gulf of Mexico. To successfully execute this science mission, NOAA is seeking to employ a UAS capability that can operate in this mode for multiple hours per deployment at ranges well beyond visual line of sight (BVLOS) while transmitting real-time data from imaging payloads. Success for this effort will mean that NOAA has developed an innovative use of UAS technology to address a critical mission area, while also helping the agency to establish vessel-based, BVLOS UAS operations, which are to be built upon for this and other important applications.

Requirements for this Statement of Work include payload integration and testing support, platform operations and testing support, UAS ground equipment lease, and pilot flight services for the NMFS BVLOS marine mammal detection and assessment initiative. These requirements also include the ability to execute all platform and integrated payload testing aboard an at sea vessel prior to acceptance and operations from a NOAA vessel. An additional requirement of this Statement of Work includes the capability to autonomously launch and recover the UAS from a vessel within a confined deck space footprint. The UAS must be capable of sustained flight for a minimum 4 hours, operate at distances of at least 20 nm from the vessel, and carry all required science and associated support payloads (with a combined weight of at least 10 lbs).

1.2 Background

NOAA NMFS is responsible for the stewardship of the U.S. ocean resources and their habitat.

Backed by sound science and an ecosystem-based approach to management, NMFS provides vital services for the U.S. through conservation and protection of living marine resources within about 200 miles of the nation’s coast. The resilience of our marine ecosystems and coastal communities depend on healthy marine species, including protected species such as whales, sea turtles, corals, and salmon. Because of this, the ability to conduct routine, accurate surveys of stock and health assessment has long been a critical part of the NMFS mission. In recent years the emergence of UAS has led to the realization and development of new, highly optimized CONOPS that can aid the agency in meeting these objectives.

In February 2024, an NOAA Workshop was convened in which participants representing NOAA’s Office of Marine and Aviation Operations (OMAO) and NMFS met to collaborate and select a project that would simultaneously address one or more critical NMFS objectives and advance the agency’s ability to execute UAS BVLOS operations from its ocean-faring research vessels. By consensus decision, it was determined that the NMFS Southeast Fisheries Science Center (SEFSC), in partnership with the Northeast Fisheries Science Center (NEFSC), would lead the initial BVLOS project with OMAO support as part of their sperm whale survey operations in FY2025. Participants identified the criteria and requirements for a UAS, based on a general set of CONOPS developed in the Workshop. Such requirements, which are summarized elsewhere in this document, pertain to size, range, endurance, payload capacity, and the ability to easily execute vessel-based launch and recovery.

2.0 SUPPORT AND SERVICES

NOAA has developed a list of threshold requirements for UAS platform performance and identified two imaging payloads that meet science mission requirements for the NMFS mission. This statement of work pertains to the provision of a platform that can (at minimum) meet these requirements, integration of NOAA-selected science payloads along with additional objective support payloads (e.g., gimbal, radio, Mode C transponder, etc.), integrated vessel-based system testing (aboard a non- NOAA ship), and UAS support services including operation and engineering support (aboard a NOAA ship).

3.0 DEFINITIONS AND ACRONYMS

3.1 Contracting Officer (CO)

A person with the authority to enter into, administer, and/or terminate contracts and make related determinations and findings. The term includes certain authorized representatives of the CO acting within the limits of their authority as delegated by the CO.

3.2 Contracting Officer’s Representative (COR)

A Federal employee delegated limited authority by a CO to monitor and perform specific, enumerated contract management duties related to contract planning, contract administration, technical direction and oversight, and closeout to ensure that the Contractor’s performance meets the standards set forth in the contract. See Clause 1352.201-72 CONTRACTING OFFICER`S

REPRESENTATIVE (COR) (APR 2010)

NOAA COR Point of Contact information

TBD

3.3 Government Point-of-Contact (GPC)

A Federal employee with no delegated authority by a CO. GPC is a Subject Matter Expert (SME) available to answer non-contractual questions specific to the technical requirements of this contract.

Any technical disagreements or contractual changes need to be directed to the CO.

Government Point-of-Contact Information

TBD

3.4 Quality Assurance

A planned and systematic pattern of all Government actions necessary to provide confidence that adequate technical requirements are established; products and services conform to established technical requirements; and satisfactory performance is achieved.

3.5 Quality Control

Those actions taken by a Contractor to control the production of outputs to ensure that they conform to the contract requirements.

3.6 Uncrewed Aircraft System (UAS)

Includes all elements required for flight such as uncrewed aircraft, ground control station, communication link infrastructure, and other support equipment.

3.7 Uncrewed Aircraft (UA) and Ground Control System (GCS)

An aircraft operated without the possibility of direct human intervention from within or on the aircraft. The UAS platform will be controlled by a Pilot in Command (PIC) using a Ground Control System (GCS).

3.8 Command and Control Link (C2)

The radio link system used to send commands to the uncrewed aircraft to control its flight path and function and receive uncrewed aircraft navigation and system details in near real time.

3.9 Payload Communications Link

The radio C2 link system may also be used to receive payload data and send commands to the payload system.

4.0 TECHNICAL CONTRACT REQUIREMENTS

4.1 Contract/Program Manager

The Contractor shall provide a Contract/Program Manager who shall be responsible for the performance of the work. The name of this person, and an alternate or alternates, who must act for the Contractor when the Manager is absent, must be designated in writing to the COR.

The Contract/Program Manager or alternate shall have full authority to act for the Contractor on all contract matters relating to daily operation of this contract.

The Contractor shall provide program management support that includes oversight and reporting of field/operational testing plans, schedule, project deliverables; budget and risk management;

performance/technical standards management; and technical document certification.

4.2 Contractor Workforce Responsibility

It shall be the full responsibility of the Contractor to organize, furnish, maintain, supervise, and direct a workforce, which, within the limitations of the provisions of this contract, is thoroughly capable of effectively performing the work set forth in this contract.

4.3 Quality Assurance

The Government shall evaluate the Contractor’s performance under this contract. Government personnel shall record all surveillance observations. When an observation indicates defective performance, the COR shall require the representative at the site to initial the observation. The initialing of the observation does not necessarily constitute concurrence with the observation, only acknowledgement that he or she has been made aware of the defective performance. Such surveillance shall be done according to standard inspection procedures or other contract provisions.

Any action taken by the CO as a result of surveillance shall be in accordance with the terms of this contract.

4.4 Government Point of Contact for Quality Assurance

See CAR Clause 1352.201-71, Contracting Officer’s Representative (COR).

4.5 Government furnished equipment (GFE)

The Contractor shall integrate the payloads into the UAS according to the most efficient means available while accounting for aircraft load balancing, platform operational performance, payload sensor performance, and the ability to easily change out payloads in a modular fashion.

4.6 Special Security Considerations

NOAA OMAO’s UAS Division (UASD) will coordinate airspace access and review UAS operations to ensure that safety and compliance with regulations and policy are maintained. The UAS shall not connect to the internet during flight and transmits pertinent aircraft telemetry solely to the GCS. The Contractor will inform NOAA and provide a list of any International Traffic in Arms Regulations (ITAR) and/or any EAR export-controlled components.

4.7 Performance of Contractor and/or Subcontractors

The Contractor’s performance may be evaluated during the performance of this contract and upon completion. Subcontractor information may be included for evaluation areas where the subcontractor's actions have significantly influenced the prime contractor’s performance.

A final evaluation may be uploaded to the Contractor Performance Assessment Reporting System (CPARS) at www.cpars.gov. CPARS is a web-enabled application that supports the completion, distribution, and retrieval of contractor performance information, as required by Federal Acquisition Regulation (FAR) Subpart 42.15. Contractors have 30 days to submit comments, rebut statements, or provide additional information before the evaluation is posted.

4.8 Scientific Data Rights

NOAA shall retain all rights to the science data collected during any flights, including payload and UAS platform navigational/positional data.

5.0 CLIN 0001 AND REQUIREMENTS – SUPPORT AND SERVICES

CLIN 0001 is designated for activities to support the procurement, integration, and flight testing of two exchangeable imaging systems (to be selected by NOAA) and associated hardware. The initial phase, flight test operations shall be conducted by the Contractor from a Contractor-furnished vessel.

Within CLIN 0001, two additional phases of operations will also be required: 1) advanced flight test operations onboard a NOAA vessel for a period of 6 days in support of a fully integrated, pre-mission test exercise and 2) mission flight operations onboard a NOAA vessel for a period of 25 days in support of NOAA NMFS marine mammal surveys. During the latter two phases, involving advanced flight test and mission flight operations onboard a NOAA vessel, UAS operational support and UAS equipment lease (including GCS and any autonomous launch/recovery systems) will be required. Up to 4 days of preparation / ship-integration may be allowed ahead of both NOAA vessel operations periods, while the vessel is in port.

UAS flight objectives are to autonomously deploy the VTOL-FW UAS from a NOAA vessel and transition into fixed-wing operations for at least 4 hours and at ranges of at least 20 nm while streaming real-time (full motion video) data back to the vessel from one of the imaging payloads.

Each deployment will conclude with an autonomous recovery of the UAS within a confined deck footprint, spanning approximately 20’ x 20’.

For NOAA mission flight operations in the final phase, daily tempos will nominally comprise two successful deployments per day (one in the morning and another in the afternoon) over a period of 25 days, while the NOAA vessel is underway. Flight activities are planned for operations in the Gulf of Mexico in uncontrolled airspace, both within and outside of Warning Area Airspace, which will be coordinated through assistance from OMAO UASD. Except for the 25-day period while the vessel is underway, the Contractor is responsible for securing all their own travel and incurring any lodging costs. NOAA vessel berthing for up to two individuals from the Contractor support team will be provided during the 25-day at sea period.

In this SOW, “payload” comprehensively refers to the two imaging systems selected by NOAA and all other supporting hardware components, integrated into the UAS platform.

Integration/installation shall include all modifications to the platform fuselage, power, and data connection to ensure that capability exists to easily integrate and quickly exchange payloads, as needed. Both imaging systems will need to be integrated and fully functional, simultaneously, for the duration of each deployment.

5.1 Task 1 - Integrate NOAA-selected Payloads onto UAS Platform and Demonstrate Shipboard Launch and Recovery from a Moving Vessel

The Contractor shall integrate the NOAA-selected imaging systems, described in Section 8 onto the Contractor-owned UAS platform, along with all other operational support payloads (e.g., gimbal, radio, Mode C transponder, etc.) needed to satisfy NOAA BVLOS UAS operational mission requirements. The Contractor shall then demonstrate flight testing and shipboard launch and recovery from a moving vessel. The Contractor shall furnish its own vessel for the vessel flight testing and provide documentation of these efforts, including but not limited to:

● Number of vessel-based launch and recovery operations

● Corresponding number of flight hours per vessel-based launch and recovery deployment

● Sea state conditions at the vessel during the launch and recovery phases of each deployment

● Atmospheric conditions during the launch, flight operations, and recovery phases of each deployment. For the launch and recovery phases, this information shall include wind speed and direction conditions at the vessel location, both from “fixed point” and “relative to the bow”.

● Information describing the performance of integrated imaging systems, including real-time streaming of full motion video

The objective of this task is to thoroughly demonstrate the following, under a range of sea state and atmospheric conditions:

● Demonstrate autonomous shipboard launches and recoveries from a moving vessel, at sea

● Demonstrate successful operations of the fully integrated payload

● Demonstrate successful UAS platform operations, meeting all minimum requirements

● Demonstrate and identify the outer limits of C2 and real-time data telemetry of the integrated UAS platform

The following represents a summary of Contractor responsibilities during Task 1:

1. Make available a UAS platform with a total payload capacity of at least 10 lbs that is capable of stable, vessel-based, autonomous VTOL launch/recovery and prolonged FW operations in a maritime environment

2. Integrate NOAA-selected imaging systems, along with other systems needed to meet NOAA’s minimum performance operational requirements, based upon airframe payload weight and center of gravity constraints

3. Coordinate with corresponding airspace authorities to obtain clearances and prepare for UAS operations (including BVLOS)

4. Conduct operational testing of autonomous, vessel-based UAS launch and recovery from a Contractor-furnished vessel with flights at ranges of at least 20 nm for at least 4 hours per deployment while the vessel is underway

5. Develop and provide required documentation of test flights based from the Contractor-furnished vessel

The following represents a summary of Government responsibilities during Task 1:

1. Identify scientific imaging systems for payload integration and provide name and model for each

2. Upon request, provide additional information pertaining to requirements for operations and applied science objectives

Advancement from Task 1 to Task 2 (and following tasks) shall only occur upon Contracting Officer written notice to proceed. The transition between Task 1 and Task 2 will be dependent on successful shipboard launch / recovery demonstration, payload testing, and delivery of required vessel flight test documentation.

5.2 Task 2 - Lease Aircraft Equipment and Operations Support for NOAA Vessel Pre-Mission Test Exercise

The Contractor shall furnish, via lease, the payload-integrated UAS platform and supporting equipment (including GCS, any autonomous launch/recovery systems, and additional equipment deemed necessary for redundancy) that were successfully demonstrated in Task 1 and provide vessel-based VTOL-FW UAS operations support services for the Pre-mission Test Exercise aboard a NOAA vessel. In general, this effort will include:

● Shipping and Integration/Installation of UAS platform and supporting equipment onto the NOAA vessel, while in port

● UAS flight operations support while the NOAA vessel is underway for a period of up to 6 days, including multiple launches, flights, and recoveries out to reasonably safe limits according to test flights undertaken during Task 1

● De-integration of UAS platform and supporting equipment from the NOAA vessel at the conclusion of the pre-mission test exercise

During the lease period for the Pre-Mission Text Exercise, the Contractor UAS will be operated as a NOAA “State Aircraft” for the implementation of this Task. NOAA and the Contractor will enter into a separate leasing agreement regarding State Aircraft policies, liability, and operational roles and responsibilities.

The following represents a summary of Contractor responsibilities during Task 2:

1. Assist with planning and Pre-mission Test Exercise deployment preparation

2. Facilitate shipping and integration/installation of UAS platform, GCS, and all related support equipment onto the NOAA vessel selected for the NMFS survey mission

3. Provide pilot and engineering support staff for integration/installation, flight operations, and troubleshooting

4. Maintain responsibility for all UAS flight operations, safety, and adherence to airspace requirements in support of the NOAA Pre-mission Test Exercise

5. Mobilize aboard a NOAA vessel for a period of up to 6 days

6. Make best efforts to support UAS flight operations in support of the Pre-mission Test

Exercise, demonstrating a minimum of 4 hour endurance per deployment at ranges beyond 20 nm

7. Coordinate objectives and flight profiles with NOAA operations and scientific personnel

8. Ensure that data produced from operations is consistently transmitted and is of sufficient quality for use by NOAA scientists to support the subsequent NMFS Marine Mammal Survey Science Mission. (Note: In addition to UAS platform C2, at minimum, the data link should support transmission of real-time full motion video).

9. Support system installation/de-installation, system checkouts, and scientific systems integration onsite

The following represents a summary of Government responsibilities during Task 2:

1. Coordinate with DoD and/or other corresponding airspace authorities and the Contractor to obtain clearances and prepare for UAS operations (including BVLOS)

2. Provide science and engineering support personnel onsite during operations

3. Provide berthing aboard NOAA vessel for required Contractor personnel

5.3 Task 3 - Lease Aircraft Equipment and Operations Support for NOAA Vessel Mission Involving NMFS Marine Mammal Surveys

The Contractor shall furnish, via lease, the payload-integrated UAS platform and supporting equipment (including GCS, any autonomous launch/recovery systems, and additional equipment deemed necessary for redundancy) that were successfully demonstrated in Tasks 1 and 2. The Contractor shall also provide vessel-based VTOL-FW UAS operations support services for the NOAA Marine Mammal Survey Science Mission aboard a NOAA vessel. In general, this effort will include:

● Shipping and Integration/Installation of UAS platform and supporting equipment onto the NOAA vessel, while in port

● UAS flight operations support while the NOAA vessel is underway for a period of up to 25 days, including multiple launches, flights, and recoveries out to reasonably safe limits according to test flights undertaken during Tasks 1 and 2

● De-integration of UAS platform and supporting equipment from the NOAA vessel at the conclusion of the operational science mission

During the lease period for the NOAA Marine Mammal Survey Science Mission, the Contractor UAS will be operated as a NOAA “State Aircraft” for the implementation of this Task. NOAA and the Contractor will enter into a separate leasing agreement regarding State Aircraft policies, liability, and operational roles and responsibilities.

The following represents a summary of Contractor responsibilities during Task 3:

1. Assist with planning and deployment preparation for the NOAA NMFS marine mammal science operations mission

2. Facilitate shipping and integration/installation of UAS platform, GCS, and all related support equipment onto the NOAA vessel selected for the NOAA NMFS survey mission

3. Provide pilot and engineering support staff for integration/installation, flight operations, and troubleshooting

4. Maintain responsibility for all UAS flight operations, safety, and adherence to airspace requirements in support of the NOAA NMFS survey mission

5. Mobilize aboard a NOAA vessel for a period of up to 25 days

6. Make best efforts to support flight operations twice per day (once in the morning and once in the afternoon) at a minimum of 4 hours per deployment at ranges beyond 20 nm

7. Coordinate objectives and flight profiles with NOAA operations and scientific personnel

8. Ensure that data produced from operations is consistently transmitted and is of sufficient quality for use by NOAA scientists in support of the NMFS Marine Mammal Survey Science Mission. (Note: In addition to UAS platform C2, at minimum, the data link should support transmission of real-time full motion video).

9. Support system installation/de-installation, system checkouts, and scientific systems integration onsite

The following represents a summary of Government responsibilities during Task 2:

1. Coordinate with DoD and/or other corresponding airspace authorities and the Contractor to obtain clearances and prepare for UAS operations (including BVLOS)

2. Provide science and engineering support personnel onsite during operations

3. Provide berthing aboard NOAA vessel for required Contractor personnel

6.0 PERIOD OF PERFORMANCE AND SCHEDULE

6.1 CLIN 0001 - Support and Services

The POP spans approximately 8 months, but actual “active periods” are embedded within this timeframe and broken down into each of the three tasks. During Task 1, the Contractor shall have up to nearly 3 months to complete payload procurement, integration, development, and testing.

Active periods within Tasks 2 and 3 are constrained by access to the NOAA vessel, including onsite, pre-deployment integration onto the ship, operational days aboard the ship, and de-integration days after the conclusion of operations.

Task Section Task Delivery Date

Task 1 5.1 Integrate NOAA-selected Payloads onto UAS Platform and Demonstrate Shipboard Launch and Recovery from a Moving Vessel

Dec 16, 2024 – Mar 14, 2025

Task 2 5.2 Lease Aircraft Equipment and Operations Support for NOAA Vessel Pre-Mission Test Exercise

Apr 05 – Apr 14, Task 3 5.3 Lease Aircraft Equipment and Operations Support for NOAA Vessel Mission Involving NMFS Marine Mammal Surveys

Jul 21 – Aug 18,

7.0 DELIVERABLES

7.1 Deliverables CLIN 0001

1. Make available a UAS platform with a total payload capacity of at least 10 lbs that is capable of stable, vessel-based, autonomous VTOL launch/recovery and prolonged FW operations in a maritime environment

2. Complete integration of NOAA-selected imaging systems, along with all other necessary payload components needed to meet NOAA’s minimum performance operational requirements

3. Conduct vessel-based operational testing, and provide required documentation indicating that the UAS (with integrated payloads) has successfully launched multiple times from an underway vessel (furnished by the Contractor), operated for a minimum of 4 hours per deployment up to a range of at least 20 nm, landed on the underway vessel under a variety of atmospheric and sea state conditions, and that all science data from the NOAA-selected imaging systems is being collected and/or streaming properly (refer to Section 8)

4. Provide required equipment and operational support services to facilitate NOAA Pre-Mission Exercise Test operations (April 2025)

5. Provide required equipment and operational support services to facilitate NOAA Marine Mammal Survey Science Mission (July / August 2025)

6. Ensure that data produced from operations is consistently delivered and transmitted with sufficient quality for use by NOAA scientists in support of NOAA’s Pre-Mission Exercise Test and NMFS Marine Mammal Survey Science Mission. At minimum, the data link should support transmission of real-time, full motion video.

8.0 PAYLOAD DESCRIPTIONS

Scientists from the NOAA NMFS project team have selected two camera imaging systems, required to support the NOAA Marine Mammal Survey Science Mission. Both systems shall be procured and integrated by the Contractor onto the UAS platform to enable simultaneous data collection and delivery in accordance with the below requirements.

8.1 High-resolution Nadir Imaging System (Sony ILX-LR1)

For collection of high-resolution, still photos of marine mammals, the NOAA NMFS science team has selected the Sony ILX-LR1 camera. The camera shall be integrated in such a way as to ensure that all photos will be collected from a “nadir” perspective and that the camera system can be modularized for easy exchange with another Sony ILX-LR1 or comparable camera.

Based on a combination of flight altitude and camera zoom options, the goal will be to collect high-resolution nadir pictures at resolutions of approximately 2-5 cm GSD. NOAA’s current minimum requirement will be to collect and store all high resolution pictures onboard the camera during UAS flights and retrieve the imagery after recovery of the aircraft for later processing. However, NOAA is also interested in pursuing a capability that will enable (in the future) real-time transmission of this high resolution data for immediate processing.

8.2 Full Motion Video Imaging System (Trillium HD55-VV)

For collection of streaming, full motion video, the NOAA NMFS science team has selected the Trillium HD55-VV camera, with onboard target tracking capability. The camera shall be integrated in such a way as to ensure full 360° imaging functionality and that the camera system can be modularized for easy exchange with another Trillium HD55 or comparable camera.

The purpose of this system is to rely upon the broad spectrum of pan, zoom, and streaming capabilities to identify and track marine mammal targets of interest, then strategically position the platform overhead to enable capturing of high-resolution nadir photos from the other camera system.

In the future, NOAA may consider the addition of an advanced software processing capability to improve upon the real-time identification and tracking of specific marine mammals, based on the real-time video provided by this camera.