The document outlines the non-conformance management process, emphasizing different types of concessions including design, manufacturing, assembly, storage, and maintenance repair and overhaul (MRO). It details the identification and resolution of non-conformances at each stage, along with the criteria and methods for handling acceptability and corrective actions. The document also references relevant aerospace quality management standards and highlights the importance of comprehensive documentation and approval processes.

1. Concession Activity
A Non Conformance Management Process
An approach to basic understanding and work on solving
problems In Non Conformance Management process based
on Experience and studies
Harsha Subbanna

2. WHAT IS CONCESSION?
When we look into the dictionary we get the following “an
agreement or settlement of a dispute that is reached by each side
making compromise for a acceptance of win situation
In industrial terms it can be Defined as “ a decision taken for
acceptability of product Fit Form and Function when deviated
within standards” or “approval of the Non Confirming product to
accept by detail study on problem caused and effects on
acceptance and define the corrective, predictive and preventive
actions to be taken to accept the product.

3. IDENTIFICATION OF
NON CONFORMANCE
Identification of Non Conformances can reported during
1) Design
2) Manufacturing
3) Assemblies
4) Storage
5) MRO (maintenance repair and overhaul)
Each has its own criteria to identify NC and to take decision
to get acceptability

4. DESIGN CONCESSION
This is done if there is mismatch with designed product with respect to
at higher level
• Customer specification and requirement
• Statutory and regulatory requirement
• Methods and process followed by Industry
at lower level
• Dimensional Fits and Tolerances b/w parts including GD&T
• Quantity used v/s BOM kitting quantitates
• Location and method of assembly
• Stress analysis and standard Shape and size
The Process used to identify and solve with approval Varies according to
Company Design process and Design Outsourced Capability to handle
Design flow process including but not limited to Design Expertise , Quality
checks , Documentations and Design audits Stress analysis, concurrent
engineering Etc…

5. DESIGN CONCESSION
Design
office
Higher
level
Lower
level
NC identified
Customer
spec
regulatory
Methods
Customer
Focal
closeNC
FAA
Engineer
Customer
approval
FAA
approval
Methods
Engineer
Process
approval
Dimension
GD&T
Functional
aspect
Quantity
Stress
Design
Engineer
Stress
Engineer
Principle
Engineer
Design
approval
Stress
approval
NC
Y
N
N
N
N
N
N
Y
Y
Y
Y
Y
Y
Y
Y
Detail
Design and
Stress NC

6. MANUFACTURING CONCESSION
This is done if there is mismatch with Manufactured product with respect to
Designed Product such as
1) Material used
2) Dimensional Tolerances
3) GD & T Tolerances
4) Surface Tolerances
5) Manufacturing Damages ( Holes, Threads Bushing holes and pins)
6) Plating Coating and painting
7) Stress induced during manufacturing
8) Heat treatment related deviations
The Process used to identify and solve with approval Varies according to
Company manufacturing process and Manufactured Outsourced Capability
to handle manufacturing process including but not limited to
Manufacturing Expertise , Quality and inspection Controls,
Documentations and Manufacturing audit trails , Worst case analysis
concurrent engineering Etc…
Y

7. MANUFACTURING CONCESSION
Manufacturing
Manufac
turing
Design
NC identified
Material
Manufacturing
Damage
Process
Metrology
closeNC
Manufacturing
approval
Design Approval
Methods
Engineer
Y
N
N
N
Y
Y
Y
Follow design NC process
Y
alternate
Heat
Treatment
Surface
Treatment
Manufacturing
Engineer
Rework/ScrapStressed
Y
N
N
Y

8. ASSEMBLY CONCESSION
This is done if there is mismatch with assembled product with respect
to Designed Product such as
1) Assembly functional Key Tolerances
2) Production Damages
3) Mismatch in Assembly quantity
4) Damages done during Assemblies
5) Alternatives parts / methods.
6) Wrong assembly Done
7) COTS (Commercial off-the-shelf)and Variants issues.
8) Obsolete
The Process used to identify and solve with approval Varies according
to Company Assembly process and Assembly Outsourced Capability to
handle Manufacturing and Assembly process including but not limited
to Assembly Expertise , Assembly Inspection Controls, Documentations
and Assembly audit trails , concurrent engineering Etc…

9. STORAGE CONCESSION
This is done if there is mismatch with Storage of products during logistics
and inventory warehouse such as
1) Corrosion and galvanisation
2) Breakages due to handling, Cracks and indentation
3) Shelf life issue and Expiry Dates
4) Contamination
5) Identification and tractability
6) Logistic packaging and damages ,scratches and chip off of materials
7) Environmental impact during storage
The Process used to identify and solve with approval Varies according to
Company logistic and inventory process and logistic Outsourced
Capability Warehouse capability to handle inventory and storage process ,
logistic packaging handling including but not limited to Repair Process,
Environmental control Process , Packaging Expertise , Loading And
unloading Expertise, Quality and inspection Controls, Documentations and
warehouse audit trails , Supply chain Management Etc…

10. STORAGE CONCESSION
Wear
house
Inventory
Logistic
NC identified
Storage
environmental
Traceability
Inventory
mangment
closeNC
Environmental
Engineer
OEM
approval
SCM
Engineer
Design
approval
Packaging
Contamin
ation
Load/
unload
Break/
Damage
Packaging
Logistic
planner
Methods
Engineer
Logistic
approval
Y
N
N
N
N
N
N
Y
Y
Y
Y
Y
Y
Y
Y
SCM
approval

11. MRO CONCESSION
This is done if there is mismatch with Parts/Assemblies with Required
condition of the product and Replacements During Maintenance Repairs
and Overhauls, and service engineering activity such as
1) Wear limits and service limits
2) Replacement parts and spares
3) Obsolescence management
4) Contamination and corrosion
5) Service methods and Repair process
6) Assembly tool Damages / Missing tools, Equipment's
The concessions may revoke any of the earlier Activities such as Design,
Manufacturing, Assembly and storage activities.
The Process used to identify and solve with approval Varies according to
Company , MRO Process and Capability to handle Maintenance and
Repair process Including but not limited to Service Process, Maintenance
Expertise ,Documentations and service audit trails ,MRO Management
Etc…

12. MRO CONCESSION
MRO
Design
Stress
NC identified
Repair
Repair
engineering
closeNC
MRO
approval
Design
approval
Y
N
N
Y
Y
Airline
approval
MRO
Function
N
N
N
Replace
Obsoloce
nce
Follow Design/Stress NC process
Principle
Engineer
Y
Design
Validation
Maintenance
OEM
approval
N
New design
Alternate
Y
Y
Y
N
N

13. DETAIL DESIGN & STRESS CONCESSION
NC identified
Concession
request
Design/
Stress NC
Concession
SAP
Design
analysis
Design repair
procedure
Design
approval
Design
dept
Stress
Analysis
Static
Stress
approval
FEM
F & DT
Validation
Functional
Analysis
Methods and
process
Principle
Engineering
approval
Concession
Approval
OEM
approval
Change
Approved
Concession
approval
Signatories

14. NC DISPOSTION
Acceptance
-Use AS IS – no change
- Repair and Use – corrective action report
- Rework and Use – corrective action report
- Next Limit approval –Corrective action one time report
Rejection
- Redo/Reprocess and use –Preventive action report
- Salvage – prevention of failure
- Obsolescence – predictive action and Prevention
Report

15. NC STANDARDS PROCEDURES
All related Standards for Aerospace is done by SAE
NC Identification is a part of AS9100D clause 8.7 control of non
confirming outputs
A Detailed Standard of NC handling is done in AS9131 Quality
management standard – Aerospace - Non conformance
documentation
AS9131 Also contains Codification of Non Conformance reporting
and codifying affected processes, causes of process deviations,
and corrections made to remedy the nonconformity.
It also define the sample Report with mandatory 34 items to be
declared (sample example Form shown from AS9131)

17. CONCESSION DESIGN CALCULATIONS
There are many areas/ NC reported based on Dimensions and tolerances
which include Calculations
Some of the calculations are identified here
1. Dimensional limit Calculation
2. Gap Analysis
3. Clearance Calculation
4. Wear limits
5. Salvage limits
6. Coating Thickness calculation
7. Tolerance stack up analysis
8. Manufacturing stack up analysis
9. Grip length calculation
10. Stress Analysis hand calculations

18. CONCESSION DESIGN CALCULATIONS
4 stages of limit calculation will be done and worst case models
are done
I. Dimensional Limit .
II. Wear Limit .
III. Repair Limit .
IV. Salvage Limit.
If the model crosses all the limits then it is salvaged
There are models created for worst case including MAX/MIN Limit
models , Wear limit models ,Salvage Limit models to check the 3D
model of actual scan with Designed models in DPD

19. CONCESSION REPORT
Concession report will Have
a. Details captured from NCR(Non Conformance Report).
b. Details of Design and methods including drawings and
Problem identified (inputs).
c. Calculations Carried out.
d. Studies conducted.
e. Justification/Decision Disposition.
f. References and Documents.
g. Corrective actions.
h. Preventive and predictive actions report.
i. Details of REWORK/REPAIR process.
j. Approval Signatories

20. QUESTIONS ?
THANK YOU
Harsha Subbanna