DBRS SRD_RFI.docx

CUI

SYSTEM REQUIREMENTS DOCUMENT (SRD)

For the Databus Recording System (DBRS)

PROGRAM

DISTRIBUTION D. Distribution authorized to Department of Defense and U.S. DoD contractors only; CTI; [18 March 2025]. Other requests for this document must be referred to the C-17 System Program Office, AFLCMC/WLM, 660 Eleventh Street, Robins AFB, GA 31098-2428.

Warning – This document contains technical data whose export is restricted by the Arms Export Control Act (Section 2751 of Title 22, United States Code) or the Export Control Reform Act of 2018 (Chapter 58 Sections 4801-4852 of Title 50, United States Code). Violations of these export laws are subject to severe criminal penalties. Disseminate in accordance with provisions of DoD Directive 5230.25 and DoD Instruction 2040.02.

Controlled by: AFLCMC Controlled by: WLM CUI Category: Controlled Technical Information Distribution/Dissemination Control: D POC: Spencer Stubbs, spencer.stubbs@us.af.mil

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DOCUMENT INFORMATION

Document Type Draft Original Release Date

Preparing Organization (if different from owning organization)

AFLCMC/WLME

AUTHOR:

Lead Engineer

Date

APPROVAL:

Lead Program Manager

Date

APPROVAL:

Chief Engineer

Date

Revision Summary:

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TABLE OF CONTENTS

SCOPE

This System Requirements Document (SRD) establishes the requirements for the C-17 Databus Recording System (DBRS) Program.

System Identification The C-17A Globemaster III Program Office (AFCMC/WLM) requires a system capable of capturing all data that is present across select databuses and computers of the C-17 aircraft. The DBRS will be capable of recording data from 1553 buses, 429 buses, and 422 buses. Recorded data will be used to perform diagnostics, analysis, and otherwise support the health of the C-17 fleet. The DBRS needs to a commercial item that is modifiable to incorporate future fleet modifications and changes from the maturing maintenance program.

The DBRS will be permanently installed in the avionics rack where it will be powered using aircraft power. It needs to be a user-intuitive LRU with an aircrew/maintenance interface with data stored on a removable storage device.

System Overview The C-17A is a long-range, heavy airlifter supporting national objectives through worldwide airlift of the US and allied personnel, equipment, and supplies. The C-17A transports large payloads over intercontinental distances with or without air refueling, provides strategic and intra-theater airlift where operating conditions permit via air, land, or airdrop, and augments aerial evacuation, nuclear weapon transport, and special airlift missions. It provides the flexibility to easily transition between delivery modes by allowing in-flight reconfiguration. The C-17A’s major contribution to the present airlift system is long-range direct delivery. Its design allows delivery of outsized and oversized cargo and equipment (with operators) directly into an austere environment. The C-17A also transports flexible cargo payloads, to include paratroopers and their equipment.

The C-17 Globemaster III is the United States’, and allies’, core military airlifter. It continues to excel in a wide range of operational mobility mission scenarios. The C-17 Program Office initiated the Full-Scale Engineering and Development contract in 1985 to develop a single weapon system to meet the needs of tactical and strategic airlift capability. Initial squadron operations began in June 1993 with the first aircraft delivery to Charleston AFB SC; the Commander of the Air Mobility Command (AMC) declared initial operational capability on 17 January 1995. The final USAF C-17 aircraft was delivered to Charleston AFB, SC on 12 September 2013.

At this point in time, there is no defined retirement date for the C-17 Weapon System.

APPLICABLE DOCUMENTS

General The documents listed in this section are specified in sections 3 or 4. This section may also include documents recommended for additional information or as examples. While every effort has been made to ensure the completeness of the document list, document users are cautioned that they must meet all specified requirements of documents cited in sections 3 or 4, whether or not the documents are listed. Where a revision by supplement, amendment, or notice is called out, the entire document up to and including the revision is being referenced. When a revision letter or date is not shown, the issue in effect on the release date of this specification applies.

Government Documents Government Specifications, Standards, and Handbooks The following specifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. Copies of these documents are available online at http://quicksearch.dla.mil// or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 19111-5094.

MIL-HDBK-454C

General Guidelines for Electronic Equipment

21-Sep-21

Other Government Documents, Drawings, and Publications The following other Government documents, drawings, and publications form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract.

Non-Government Publications The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract.

SYSTEM REQUIREMENTS

Functional Requirements SRD 1-1 - The DBRS shall be capable of recording data from at least (9) MIL-STD-1553 dual-channel buses, (8) ARINC 429 buses, and (2) EIA-422 buses simultaneously.

SRD 1-2 - The DBRS shall be capable of recording 100% of the data from each bus.

SRD 1-3 - The DBRS shall provide synchronized, time-stamped data from each bus.

SRD 1-4 - Data shall be stored on a removable solid-state device (SSD).

SRD 1-5 - The SSD must be accessible without the need to remove the DBRS from the avionics rack.

SRD 1-6 - The SSD capacity shall be sufficient to have 33% capacity remaining after recording 1,000 flight hours at peak transmission rates.

SRD 1-7 - The DBRS shall support the removal and replacement of the SSD while powered on without interruption to operations.

SRD 1-8 - The SSD shall use an industry standard connector to download data.

SRD 1-9 - Data shall be recorded in an industry standard compressed format IAW MIL-STD-1840C.

SRD 1-10 - The DBRS shall not overwrite existing data when the storage capacity is reached.

SRD 1-11 - The DBRS shall have a front panel indication when it is powered on.

SRD 1-12 - The DBRS shall have a front panel indication when it is actively recording.

SRD 1-13 - The DBRS shall indicate when 10% storage capacity remains.

SRD 1-14 - The DBRS shall allow primary operation and control functions to be performed with the LRU installed in its intended use configuration without the removal of additional aircraft panels.

SRD 1-15 - The DBRS shall be expandable to record additional buses in the future.

Electrical Requirements SRD 2-1 - The DBRS shall operate with a primary power supply of 28 VDC IAW MIL-STD-704F.

SRD 2-2 - The DBRS shall be powered by 28 VDC emergency power when primary power is unavailable.

SRD 2-3 - The DRBS total power consumption shall not exceed 6A at 28VDC (168 Watts).

SRD 2-4 - The DBRS power interface shall be compatible with a D38999/26WB98SN connector IAW MIL-DTL-38999N.

SRD 2-5 - The DBRS shall default to a powered-on state.

SRD 2-6 - The DBRS shall default to a recording state.

SRD 2-7 - The DBRS shall be capable of being manually shut off without removing the LRU or engaging the circuit breaker.

Environmental Requirements SRD 3-1 - The DBRS shall not require air flow greater than 8 lbm/min for cooling.

SRD 3-2 - Any system flow through requirements shall conform to ARINC 404A.

SRD 3-3 - Flow through method of cooling shall have a total pressure loss through the DBRS no greater than 1 inch of water with a design goal of 0.2 inch of water when supplied with a flow rate of 8 lbm/min per kilowatt at 32°C and 14.7 psia.

SRD 3-4 - The DBRS shall withstand a cooling air temperature range of -54 to +71°C while not in operation.

SRD 3-5 - The DBRS shall withstand, while operating, a cooling air temperature range of +71°C to 32°C in 39 seconds during ground operation (initial cool down).

SRD 3-6 - The DBRS shall withstand, while operating, a cooling air temperature range of +32°C to +7°C in 25 seconds during climb.

SRD 3-7 - The DBRS shall withstand, while operating, rates of inlet cooling air temperature change up to 60°C/min. during ground transient warm up starting from -54°C.

SRD 3-8 - The DBRS shall operate with cooling air that contains no more than 0.001 grams of solid contamination per pound of air, and 95 percent of particles less than 20 micron in size, and no particle larger than 50 microns in size without degradation in performance.

SRD 3-9 - The DBRS shall operate in the following cooling normal conditions:

1. (Ground case) At cooling flow rate of 8 lbm/min x w per kilowatt of equipment maximum heat dissipation at a supply temperature of 32°C and an ambient pressure between 31.89 in Hg and 18.70 in Hg, where w is defined as the ratio of ambient pressure to 29.92 in Hg.

2. (Flight case) At cooling flow rate of 6.47 lbm/min per kilowatt of equipment maximum heat dissipation at a supply temperature of 7°C in a pressure environment equivalent to 8,000 ft. altitude.

3. (Airdrop) For one hour during a high-altitude airdrop with fuselage depressurized, at cooling flow rate of 2.7 lbm/min per kilowatt of equipment maximum heat dissipation at a supply temperature of 10°C.

SRD 3-10 - The DBRS shall operate in the following cooling extreme conditions:

1. (Minimum Continuous) At cooling flow rate of 8 lbm/min per kilowatt of equipment maximum heat dissipation at a supply temperature of -40°C.

2. (Maximum Continuous) At cooling flow rate of 8 lbm/min per kilowatt of equipment maximum heat dissipation at a supply temperature of 55°C.

3. (Low Flow Continuous) At cooling flow rate of 5 lbm/min per kilowatt of equipment maximum heat dissipation at a supply temperature of 32°C.

4. (Intermittent) For five minutes at a cooling flow rate of 8 lbm/min per kilowatt of equipment maximum heat dissipation at a supply temperature of 71°C.

5. (Decompression at 50,000 ft) For five minutes at a cooling flow rate of 1 lbm/min per kilowatt of equipment maximum heat dissipation at a supply temperature of 7°C.

SRD 3-11 - The DBRS shall not use internal fans without USG approval.

SRD 3-12 - The DBRS shall comply with emissions limits of MIL-STD-461G Conducted Emissions CE102, Power Leads, 10 kHz to 10 MHZ.

SRD 3-13 - The DBRS shall comply with emissions limits of MIL-STD-461G Radiated Emissions RE102, Electrical Field (Large Fixed Wing Internal requirements); Figure RE102-3.

SRD 3-14 - The DBRS shall comply with conditions of MIL-STD-461G Conducted Susceptibility CS101, Power Leads, 30 kHz – 150 kHz.

SRD 3-15 - The DBRS shall comply with conditions of MIL-STD-461G Conducted Susceptibility CS114, Bulk Cable Injection.

SRD 3-16 - The DBRS shall comply with conditions of MIL-STD-461G Conducted Susceptibility CS115, Bulk Cable Injection, Impulse Excitation.

SRD 3-17 - The DBRS shall comply with conditions of MIL-STD-461G Conducted Susceptibility CS116, Damped Sinusoidal Transients, Cables and Power Leads.

SRD 3-18 - The DBRS shall comply with conditions of MIL-STD-461G Conducted Susceptibility CS118, Personnel Borne Electrostatic Discharge.

SRD 3-19 - The DBRS shall comply with conditions of MIL-STD-461G Radiated Susceptibility RS103, Electric Field, 60 V/m.

SRD 3-20 - The DBRS shall meet the electrical bonding requirements in accordance with MIL-STD-464C, paragraph 5.11, Electrical Bonding.

SRD 3-21 - The DBRS shall withstand pressure altitudes from -1800 ft. (31.89 in. Hg.) to 50,000 ft. while continuously operating. Pressure altitudes are defined in MIL-E-5400T Class 1.

SRD 3-22 - The DBRS shall meet performance standards during a rapid and complete loss of cabin compartment pressurization of 10,300 ft. (9.99 psia) from an airplane flight altitude of 50,000 ft. (1.69 psia) within 15 seconds, the equipment will remain operating for 5 minutes at 50,0000 ft. before being returned to normal cabin pressure.

SRD 3-23 - The DBRS shall meet performance standards following a rapid and complete loss of cabin compartment pressurization of 10,300 ft. (9.99 psia) from an airplane flight altitude of 50,000 ft. (1.69 psia) within 15 seconds, the equipment shall remain operating for 5 minutes at 50,000 feet before being returned to normal cabin pressure.

SRD 3-24 - The DBRS shall withstand humidity up to 100% including conditions where condensation is occurring in and on the equipment during operating conditions.

SRD 3-25 - The DBRS shall withstand humidity up to 100% including conditions where condensation is occurring in and on the equipment during non-operating conditions.

SRD 3-26 - Materials used in DBRS components shall not become nutrients to fungus under the conditions of 95% relative humidity at 86°F for 28 days.

SRD 3-27 - The DBRS shall not develop corrosion or electrical degradation when exposed to a salt fog concentration of 5% at 95°F for 48 hours.

SRD 3-28 - The DBRS and mounts shall structurally withstand steady state inertia loads and function without degradation during and after exposure to acceleration forces.

a. Operational test shall be accomplished per MIL-STD-810H Method 513.8 Procedure II using the limit load factors listed below. Testing to be accomplished in each of the 3 major axis.

b. Crash hazard acceleration testing shall be accomplished per MIL-STD-810H Method 513.8 Procedure III using the ultimate load factors listed below. Testing to be accomplished in each of the 3 major axis.

SRD 3-29 - Any new DBRS support structure components shall be analyzed to the load factors above. For ultimate loads, structure can deform but must remain in place and not block egress paths.

SRD 3-30 - The DBRS shall meet performance standards during and after shock testing per MIL-STD-810H Method 516.8 Procedure I and Procedure V.

a. Procedure I Functional Shock shall be accomplished with the equipment operational and demonstrates it can function during and after shocks. Repeat testing for each of the 3 primary axis.

b. Procedure V Crash Hazard Shock shall be accomplished, testing will demonstrate the equipment will be contained during a crash and not create an egress hazard. Repeat testing for each of the 3 primary axis.

SRD 3-31 - Vibration testing shall be accomplished per MIL-STD-810H Method 514.8 Procedure I at the Functional and endurance at the breakpoint levels listed below. Duration will be at least 30 mins functional, 60 mins endurance, and 30 mins functional and be repeated on each of the 3 major axes.

SRD 3-32 - Exposed metal surfaces of the DBRS shall not exceed a temperature of 120°C.

SRD 3-33 - Exposed glass surfaces of the DBRS shall not exceed a temperature of 138°C.

SRD 3-34 - Exposed plastic surfaces of the DBRS shall not exceed a temperature of 156°C.

Reliability, Availability, and Maintainability SRD 4-1 - All modified equipment shall preclude improper installation, mounting, or connection of LRUs, assemblies, subassemblies, cables, or lines IAW MIL-STD-1472H.

SRD 4-2 - All connections located within 6 inches of each other shall be physically non interchangeable except when the connectors are specifically designed to be interchangeable for supportability reasons; clearly marked as to their correct installation and unable to cause damage to the installed system IAW MIL-STD-1472H.

SRD 4-3 - The DBRS shall have operator manuals to support all tasks necessary for operation and control of the item.

Computer Resources Requirements SRD 5-1 - The DBRS shall have a minimum of 40% spare installed processor memory.

SRD 5-2 - The system computers shall have at least 30% spare processor throughput/processor utilization under heaviest loading conditions.

SRD 5-3 - The instruction set for each of the computers shall be appropriate to the intended application, and addressing ranges and modes shall be adequate for the application and amount of memory employed, including expansion.

SRD 5-4 - The instruction set for newly developed computer program configuration items and computer software configuration items shall be approved by the USG.

SRD 5-5 - The DBRS shall be designed to perform an orderly shutdown if power is outside the specification limits per MIL-STD-704F. This will include storing of critical data and parameters.

SRD 5-6 - The DBRS shall initiate an orderly recovery within five seconds upon return to normal power conditions without operator intervention.

SRD 5-7 - The DBRS shall generate and store logs in memory.

SRD 5-8 - The DBRS shall provide the capability to recover to a known state in near real-time.

SRD 5-9 - The DBRS shall perform cryptographic operations IAW FIPS 140-3 Level 2 validated cryptographic module without performance degradation.

SRD 5-10 - The system shall employ sanitization processes on media and volatile memory storage IAW S/CSS Policy Manual 9-12, NSA Storage Device Sanitization.

SRD 5-11 - Sanitization mechanisms shall be employed with the strength and integrity commensurate with the security category or classification of the information.

SRD 5-12 - The DBRS shall not transmit on, nor cause any adverse impacts to, the aircraft databuses or functionality.

SRD 5-13 - The DBRS shall zeroize all non-volatile memory upon command

Physical Characteristics SRD 6-1 - The DBRS shall consist of a single Line Replaceable Unit.

SRD 6-2 - The DBRS shall utilize 128 pin D38999/20WJ35AN and 128 pin D38999/20WE35AN connectors on the rear panel to interface with the aircraft IAW MIL-DTL-3899N.

SRD 6-3 - The DBRS shall have an output interface that allows in-flight transfer of recorded data in near real-time.

SRD 6-4 - Data transferred through the output interface shall be pulled from the SSD such that it remains encrypted.

SRD 6-5 - The DBRS shall have an aircrew/maintenance interface that can be used during ground and in-flight operation.

SRD 6-6 - The aircrew/maintenance interfaces shall not impact recording operations if used during ground and in-flight operation.

SRD 6-7 - The DBRS shall not exceed the physical dimensions (width, height) of an ARINC 404A ½ ATR case, with an L2 length of 12.62 in.

SRD 6-8 - The DBRS shall mount securely to the C-17 avionics rack

a. Threshold: using a tray provided by the vendor.

b. Objective: using standard ARINC 404A Type A hold down in the front and solid pin/hole in the rear.

SRD 6-9 - The DBRS and any necessary components for mounting shall weigh no more than 19 pounds.

Materials and Finishes SRD 7-1 - All potentially hazardous materials used in the systems shall be managed following AFI 63-101/20-101 paragraph 5.4.11. In addition, the materials are prohibited from use in all delivered hardware, including COTS hardware, and in the operational support of the aircraft with its installed system. Asbestos, Carbon Tetrachloride (Tetra chloromethane), CFCs (-11, 12, 13, 111, 112, 113, 114, 115, 211, 212, 213, 214, 215, 216, and 217), CFC blends (R-500, 501, 502, and 503), hydrazine, methyl bromide, PCBs, Radioactive material, Trichloroethane (methyl chloroform), Halons (-1011, 1202, 1211, 1301, and 2402).

SRD 7-2 - Materials and processes shall be in accordance with MIL-STD-1587E Material and Process Requirements for Aerospace Weapons Systems and MIL-STD-1568E Materials and Processes for Corrosion Prevention and Control in Aerospace Weapon System.

SRD 7-3 - Magnesium parts shall be protected IAW T.O. 1-1-691 and coated with 3 mils of corrosion resistant primer and 6 mils of polyurethane topcoat.

SRD 7-4 - Adhesive sealants used to seal and/or protect terminations shall conform to MIL-A 46146B (or equivalent), MIL-S-8784B, AND MIL-A-46106B as appropriate.

SRD 7-5 - Conformal coating shall conform to MIL-I-46058C (or equivalent).

Support Equipment SRD 8-1 - The DBRS shall include any hardware or software necessary to transfer data from the SSD to a USB 3.0 port.

SRD 8-2 - All newly developed SE shall be designed in accordance with MIL-S-8512D including Amendment 2 (MIL-S-8512(s)), MIL-STD-46855A, MIL-PRF-28800G, and MIL-STD-1472H.

SRD 8-3 - All newly developed electrical/electronic test equipment shall be selected/designed and constructed in accordance with the requirements stated in MIL-PRF-28800G; MIL-HDBK-454C shall be used as guidance in the development of electronic SE.

SRD 8-4 - All newly developed electrical, mechanical, pneumatic, and hydraulic SE shall be selected/designed and constructed in accordance with the requirements stated in MIL-S-8512D.

SRD 8-5 - All newly developed designed support equipment shall use standard military or industrial parts, components, materials, and processes. Including, but not limited to, National Aerospace Standards (NAS), International Organization for Standardization (ISO), IEEE, American Society of Mechanical Engineers (ASME), and Military Standard (MS) standard parts, components, materials, and processes. Exceptions to this requirement must be approved by AFLCMC/WLME.

SRD 8-6 - All newly developed parts, components, materials, and processes deemed proprietary by the data owner shall not be used in the design and development of support equipment, with the exception of selected COTS support equipment.

SRD 8-7 - All newly developed Electronic Test Equipment shall meet the electromagnetic requirements in accordance with MIL-STD-464C.

VERIFICATION

An objective of the verification process is to ensure system requirements are understood and test methods are correctly defined and implemented. Verification of COTS/Non-Developmental Item (NDI) system components require presentation of existing qualification and certification data artifacts to ensure COTS/NDI are operationally suitable, safe, and effective in the C-17 worldwide environment. Commercial certification data for COTS/NDI may be acceptable for verification based on engineering review of data artifacts to verify system component design and performance is acceptable to meet C-17 system requirements, military missions, and aircraft usage. Similarly, all MIL-STD design requirements or test procedures shall require review of development artifacts for requirements verification and airworthiness certification.

Developmental components shall require verification throughout the development, test, and production process. Ultimately, the information generated through the verification process shall be adequate to document compliance with technical performance requirements. Unless otherwise specified, the contractor is responsible for verification of all requirements specified herein.

The Government reserves the right to monitor or perform any inspections demonstrations, analyses, or tests set forth in the specification where such inspections are deemed necessary to assure that parts, materials, or services conform to prescribed requirements.

Verification methods are described below:

Demonstration Demonstration is defined as the operation of the system or subsystem which requires observation to demonstrate requirement compliance. This verification does not require the use of instrumentation, special test equipment, or subsequent analysis.

Specific human performance evaluations, demonstrations and analysis shall be conducted to determine that the performance of any task required for operation and maintenance of the C-17A System equipment is within the capability of the military personnel who have been appropriately selected and trained to perform the task.

Test Test is defined as verification of the requirements through the application of established test procedures, usually with instrumentation, within specified environmental conditions and subsequent compliance confirmation through analysis of the data generated. This requirement may be fulfilled by submission of data which demonstrates the required test has been satisfactorily accomplished.

Analysis Analysis is defined as processing of accumulated data obtained from other qualification methods to verify requirement compliance. Examples of analysis are reduction interpolation or extrapolation of test results. This verification requirement may be fulfilled by submission of data previously produced which demonstrates the analysis has been satisfactorily accomplished.

Inspection Inspection is defined as visual verification that the system, including system documentation, conforms to the requirements specified herein. Visual verification can be in the form of inspection of the physical installation and/or review of documents reflecting qualification requirements.

APPENDIX A: LIST OF ACRONYMS

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