Basic terms in Military Airworthiness and Type of Airborne Stores
What is an Airborne Store?

Aircraft and its accessories (equipment such as hydraulic pump, generator, actuators, communication equipment, etc) including weapons (such as guns, bombs, missiles) are termed as airborne stores (aircraft itself is also an airborne store).

Who can undertake Design & Development activity of airborne stores?

A Design and Development Agency can be a government R&D organisation, public sector undertaking or a private organisation that undertakes design and development of airborne stores.

What is Airworthiness certification?

Airworthiness is the continued capability of the aircraft/equipment to perform satisfactorily and mission requirements, throughout the specified life in the prevailing environments with acceptable levels of safety and reliability. The acceptable levels to be mutually agreed between users, designers and the certification authority ‘Certification’ is a statement (by concerned authority) that a particular product has been evaluated against a defined specification/standard and meets the requirements of that specification/standard. Airworthiness certification' of an aircraft stipulates that if the aircraft is designed, manufactured to the build standard and operated as described in the Release to Service Document, it will provide the declared performance, and is safe to fly within the stated conditions over a specified span of life. This by itself does not constitute the authority to release a particular serial number of aircraft of this type for flight, unless accompanied by a 'certificate of airworthiness' for that particular aircraft issued by the RDAQA stating that the particular serial number of aircraft is manufactured to the approved drawings, and that the aircraft and systems meet the requirements of approved test schedules and hence meet the requirements of the airworthiness approval issued by Regional Centre for Military Airworthiness.

What is Ab initio design, License-built and Bought Out stores?

Ab initio design essentially refers to items produced under ‘Built to Spec’ with in-house developed technology and manufacturing process within the country. The License-built store is ‘Built to Print’ under ToT or license from a foreign OEM. The Bought out stores are off-the-shelf items procured directly from foreign sources.

What is indigenization?

Indigenization essentially refers to D&D of a store as a drop-in replacement for a OEM developed item.

How, why and who does the classification of airborne stores/ spares?

All airborne stores taken up for indigenous development shall be classified in to the following categories based on the criticality and functional importance. Flight Safety Critical: The failure of such components/ systems/ items endangers the safety of aircraft or crew. Mission Critical: The failure of such components, systems or items result in aborting the aircraft mission Non critical: The failure of components does not endanger the safety of the aircraft and crew nor does it result in aborting the mission. Criticality classification is decided in the Local Type Certification Committee (LTCC).

What is Drawing Office Procedures (DOP)?

Every design, development and manufacturing agency follow their own drawing office procedures. However, the drawing office procedure to maintain configuration control for part number/issue number/mod number need to be finalized in coordination with CEMILAC.

What is Customer Furnished Equipment (CFE) and Customer Specified Equipment (CSE) or Buyer Nominated Equipment (BNE)?

These are customer driven requirements. CFE is item/ equipment procured by the user for fitment on their platform based on the operational requirements. CSE/ BNE are stores identified to be procured and integrated by the D&D agency for the user platform.

What is meant by Aeronautical Grade Standard parts (AGS) and how are they cleared?

AGS’s are non-critical grade Fasteners/consumables which are standard in nature and generally cleared for usage across the product like: screws, rivets, gaskets etc. For these the material, component drawing, process etc. are available with the main contractor. The Main contractor along with its quality control department shall issue indigenization clearance based on test carried out as per drawings the list of such items shall be notified to TAA. The drawings and the test reports are submitted to CEMILAC /RCMA who in turn accord clearance.

Which components are defined as Commercial Off-the-Shelf (COTS)? How are COTS approved for use?

This generally refers to commercially available electronic components adopted for use in the avionic systems based on approved screening procedure to assess consistency and quality of a batch of components.

What is LCSO approved component?

These are components which are manufactured by indigenous companies as per the specifications and approved by LCSO. These items are permitted to be used at par to MIL components.

What are Critical Replacement Spares (CRS)? What is the method to clear such items?

CRS refers to the critical spares sourced from alternate or third party vendors as replacement to the OEM parts. Although critical the part does not warrant TA as it is only a replacement spare and such parts are locally cleared by the concerned RCMA which is both acceptance of design validation and verification and also service use clearance.

Who are the military airworthiness regulatory bodies in India?

Centre for Military Airworthiness and Certification (CEMILAC) is responsible through its Regional Centres for Military Airworthiness, for all activities leading to certification of fighter/transport aircraft, helicopters, engines, systems, airborne equipment, software, mid-life upgrades/life extension programmes of indigenous/license production/bought out aircraft, indigenously developed airborne stores, FOL, continued airworthiness activities like defect/incident/accident investigation, and approval of corrective actions through SIs, STIs, UONs, and modifications. Regional Centre for Military Airworthiness (RCMA): RCMA is a unit of CEMILAC, co-located at major D&D centres across the nation (Various divisions of HAL, DRDO and BRDs of IAF) which acts on behalf of CEMILAC. It deals with all aspects of technical clearance of the airborne stores during design, development, production, and in-service phase. In such places where there is no establishment of RCMA, authority may be delegated to Visiting Technical Officers (VTOs) of CEMILAC. Visiting Technical Officer (VTO) is a Rep of RCMA/ CEMILAC identified to give airworthiness coverage to projects/ activities of indigenisation or D&D where resident office (RCMA) is not available. DGAQA/ RDAQA: Directorate General of Aeronautical Quality Assurance through Regional Directorate of Aeronautical Quality Assurance is the approving authority for quality assurance during manufacture and quality assurance for all the activities listed under CEMILAC. CEMILAC is responsible for design certification of military airborne stores in the country while DGAQA address the Quality Assurance of airborne stores manufactured for Indian military.

What is an Airworthiness Group (AWG)?

It’s a part of D&D organization approved by CEMILAC to address and ensure the airworthiness practices are adopted within the organization and also interface on behalf of D&D agency with CEMILAC for clearances.

What is Quality Control (QC) and Quality Assurance (QA)?

Quality Control can be defined as “operational techniques and activities part of quality management focused on fulfilling quality requirements”. A set of activities designed to evaluate a developed work product. QC activities focus on finding defects in specific deliverable.

What is Quality Assurance Approved Firm?

Quality Assurance Approved Firm is a firm whose quality assurance organisation has been approved by DGAQA as competent to carry out quality assurance during manufacture/overhaul/repair/ storage of aircraft/aero engines and its associated equipment, accessories, and other aircraft stores. The terms and conditions for approval are given in DGAQA, Ministry of Defence document ‘Approval of Firm’s Inspection Organisation/Department’ and also ‘Quality Control System Requirements for Industry’, JSS 0254-01 April 1983.

What is Acceptable Means of Compliance(AMC)?

Acceptable Means of Compliance (AMC) represents the preferred means by which the TAA expect the intent a regulation / criteria to be met.

Various Documents, Clearances and Approvals in Airworthiness Certification
What is Provisional Clearance? Which items can be taken up for issuance of PC?

A Provisional Clearance could be issued by one of the RCMAs for an indigenously developed airborne store/ spare/ material with limited time validity, pending Type Approval by CEMILAC. While this limited period validity is restricting on the manufacture and supply of item its not to be misconstrued as product life. A Provisional Clearance is issued to the effect that the store under development meets all the laid-down specifications and test requirements with the exceptions stated therein. The Provisional Clearance is issued because documentation is pending, or because some of the long cycle life and environment tests are pending. There is no difference between a Provisional Clearance and a Type Approval in so far as the safety of the aircraft or airborne store is concerned.

What is Type Approval and what is its purpose?

Type Approval is a certificate issued by the approving authority, i.e., Chief Executive, CEMILAC to the effect that the store under reference meets all design specifications and test requirements laid down by CEMILAC. The Type Approval is issued after the D&D Agency submits a full Type Record with all the relevant documents to the satisfaction of RCMA/ CEMILAC.

Is it essential to convert a PC to TA? What are the requirements for this?

PC is issued to facilitate series production of an approved design type and invariable it should lead to a Type Approval to ensure sustained supply chain.

What are various types of staff qualitative requirements?

The Staff Qualitative Requirements document describes, in qualitative terms, the requirements for an equipment or system for user armed forces. The Air Staff Qualitative Requirements (ASR) are from the Indian Air Force, Naval Staff Qualitative Requirements (NSQR) are from the Indian Navy, General Staff Qualitative Requirements (GSQR) are from the Indian Army. In addition to these, there are common requirements called Inter-Services Staff Qualitative Requirements (ISQR) and Provisional Staff Qualitative Requirements (PSQR) which are evolved as interim requirements.

What is Operational Requirements Specifications (ORS)?

ORS is a concept of operation document that specifically captures user requirements such as operational features, performance and Man-Machine Interface (MMI) requirements.

What is Technical Specification?

Technical Specification is a document laying down design and performance characteristics of the store. The technical specification shall contain full details of the equipment, standard of the main store, the specifications/ standards followed in the design and manufacture, the environmental conditions, interface and integration requirements, besides performance and functional requirements.

What is a Type Record and what are its major contents?

Type Record is a document giving a description of the store; its functional performance characteristics; summary of strength and other calculations along with reserve factors, environmental envelope of operation and storage of the store; results of all the tests including environmental, functional and endurance tests; weight data; list of applicable drawings; and the certificate of design. It includes all documents and specifications approved by CEMILAC, information on dimensions, materials, and processes necessary to define the structural strength of the aeronautical product.

What are the responsibilities of D&D thorough out the product lifecycle?

The D&D agency has a definite role throughout the product lifecycle viz.: D&D, Production and In-service phase. The product design shall ensure design for performance, manufacturability, maintainability, reliability, safety and life under specified operating & environmental spectrum.

What is Certificate of Design (COD)? Who issues Certificate of Design (COD)?

The Certificate of Design is the document which certifies that the store complies with all the requirements laid down in the Technical Specification with exceptions quoted therein. This is issued by the Chief of Design of the D&D agency and approved by RCMA/ CEMILAC.

What is aircraft Equipment Standard of Preparation (ESOP)?

ESOP of an aircraft represents the aircraft build standard with respect to the equipment/ accessories fitted on the aircraft. Minimum equipment build standard refers to the list of equipment to be mandatorily fitted on the aircraft to ensure airworthiness.

Is it mandatory for a store to undergo Flight testing required after every MOD?

Considerable time and costs are involved in flight testing apart from availability of aircraft for testing. Flight testing shall be restricted to only such cases wherein the indigenous stores have to be tested for operation and performance under dynamic conditions of flight and environment that cannot be adequately simulated in the test rig on ground. The flight test option should be exercised judiciously.

What is Clearance for Development trials?

Clearance for Development trials is issued by the RCMA dealing with the airborne store, to a prototype item that needs to be tested and evaluated on a rig or aircraft on ground/ in-flight. This clearance alone will not constitute an authority for fitment and flight evaluation on any aircraft unless accompanied by a valid flight clearance certificate issued by the platform RCMA. This can be an iterative process till the store is matured to a level where a final service clearance is issued after completion of the flight trials and freezing the store configuration.

What is Flight Clearance Certificate (FCC)?

FCC is issued by platform RCMA to a new aircraft or an aircraft modified with the integration of a new system or a store to undertake flight evaluation and it highlights the basis, build standard, envelop, limitations and conditions of the trial. FCC can be restricted to a sortie or for a block of sorties depending on the maturity level of the development process. In case of sortie by sortie clearance flight program for each sortie has to be approved by RCMA. This alone shall not constitute any authority to undertake flight trials unless accompanied by a certificate of airworthiness issued by competent inspection authority.

What is Clearance for Service use?

Service clearance is generally platform specific and is issued to D&D agency and/ or user, after completion of development flight trials and the store is found to meet the requirements of technical specifications and contractual requirements (user’s). The build standard, conditions, limitations and envelop of operation including life limitations, as applicable, should be adequately captured in the service clearance.

Formal Committees/ Boards and their Roles
What is LTCC and what is its purpose and who constitutes the LTCC for various platforms?

Local Type Certification Committee: A committee formed with designers, users, DGAQA and headed by RD-RCMA (DDPMAS guidelines) to carry out Criticality Classification of airborne stores and also approve non-critical stores/ spares. CEMILAC forms the LTCC from time to time based on the requirements from the D&D agencies.

What are the items eligible for LTCC?

Items for which not sufficient technical information is available (non-standard), require major effort from all agencies concerned. Classification into critical, non-critical shall be decided by the LTCC.

What is Joint Airworthiness Committee (JAC)?

JAC is a Joint Airworthiness Committee formed with participation of all stakeholders to discuss and finalize any revisions to the DDPMAS document. JAC is also empowered to co-opt additional members for participation if need be.

What is Lifing Committee?

Lifing committee comprises of stakeholders & is chaired by CEMILAC based on Life revision request / proposal. This committee carries out studies and evaluations necessary to carry out the required revision

What is Safety Review Board (SRB)?

In any ab inito aircraft D&D program or a major modification to the aircraft system the SRB is constituted to review the safety levels prior to undertaking the first flight. SRB may also recommend the procedures for safe conduct of flight trials

What is Flight Readiness Review Board (FRRB)?

FRRB reviews the completion of the D&D activities including outstanding RFAs and their impact on the safe conduct flight trials and ensure readiness to undertake flight trials.

What is Local Technical Committee?

There may arise a need to introduce modifications proposed by the licensor on license built airborne stores or bought out airborne stores used on the aircraft. The licensor or Original Equipment Manufacturer (OEM) may not, however, give full details of the modification but give only such minimum details that are sufficient to submit a proposal to the LMC. In such cases, a Local Technical Committee can be constituted by the Chairman of LMC at the contractor’s works with RCMA as the chairman and members from CRI, contractors design department, production and quality departments, to evaluate the proposals of the licensor. LTC has to evaluate the modification in the absence of the detailed drawings and documentation. Those modifications that have been recommended by the LTC need to be considered by the LMC.

After issuance of TA: Transfer of Technology & Continued Airworthiness
After issuance of Type Approval, if that store is NOT procured by user and/ or NOT used during that TA validity period, what happens to its renewal request comes without performance feedback?

The absence of adverse feedback authenticated by competent authority is also treated as satisfactory performance feedback and TA renewal will be processed. Due to any reason if the OEM has not applied for TA renewal in time and there is an inordinate delay in seeking renewal, Repeat Qualification Test may be insisted by RCMA.

What happens to TA if the D&D agency does not approach the RCMA for its renewal?

The airborne stores cannot be manufactured and delivered to the users without a valid TA. The D& D agency will be solely responsible for such production holdups and AOG situations.

After TA issuance to a store, if ToT is done for manufacturing, what is the implication on the TA?

For the type approved store, in case the D&D agency wants to handover the production to an external industrial agency, the ToT document prepared by the D&D agency is to be approved by CEMILAC. Further the roles and responsibilities regarding continued airworthiness aspects such as support in Design modifications and Defect Investigations. Also the extent of TOT and subsequent responsibilities by various stakeholders are to be brought out clearly in the TOT agreement, including the onus for TA renewal.

If there is a change in Name/ Address of the D&D or Manufacturing agency after the TA is issued, how to absorb into the type approval of the airborne store?

The D&D or manufacturing agency may approach the respective RCMA which has processed the TA, along with supporting documents justifying the exact change done. In case of name change, the certificate issued by Registrar of Companies (Ministry of Corporate Affairs, GoI) acknowledging the same may be forwarded. If the work centre is relocated, the same may be verified by RCMA for adherence to SOP as disclosed during the TA. This may be ensured through Repeat Type Testing (RTT) or Limited Qualification Testing (LQT), if necessary, by the concerned RCMA.

What happens to TA if the design/ development firm is absolved and ceases to exist?

The D&D agency shall inform the RCMA/ CEMILAC about any changes in its ownership or corporate entity due to merger or takeover or if the firm is absolved and ceases to exist. The TA status in the official records shall be updated accordingly.

Software Certification
What are different categories of software used in aircraft and military aviation?

The software which is used in the aircraft and its support systems are classified into three categories as (i) Airborne Embedded Software, (ii) Ground Equipment Software and (iii) Test Rig Software. i) Airborne Embedded Software: The software which is embedded in the airborne hardware is categorized as Airborne Embedded software. The different types are: • On-board Flight Program (OFP) built from Application Software, Device Driver Software, Board Support Package (BSP) Software, and Operating System Software etc. • Test software used during the qualification or acceptance testing of the hardware to exercise and test the complete hardware of the unit under test. • Maintenance software embedded in the airborne system but not invoked in flight such as calibration software, servo characterization software etc. ii) Ground Equipment Software such as Ground Replay Software for FDRs, CDRs, CVRs, PFM Generation Software, Flight Plan Generation Software etc. iii) Test Rig Software such as Hardware-Software Integration Test Rig Software, Simulator software etc.

Is Type Approval issued to software and what is CEMILAC policy of Type Approval of software?

Generally, the softwares are developed specific to a particular end-use and as such they form part of the approval accorded for the system or platform in total. Hence a separate TA is not envisaged.

What are the important concerns in Airworthiness certification of software?

Among the above software categories, the airborne embedded softwares are of major concern in airworthiness certification because these are embedded in the systems to be installed on the aircraft and would have a direct effect on the safety of the aircraft. However, the other types of software e.g. test rig software are also important, if these are associated with some flight critical software such as test rig software used to test aircraft flight control software. The process of certification of the Ground equipment and Test rig software may be decided as per the criticality of software with which they are associated.

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