Upload
others
View
1
Download
0
Embed Size (px)
Citation preview
Federal Aviation Administration
Presented to: MARPA
By: FAA, Standards Staff, Engine and Propeller Directorate
Date: October 28, 2015
FAA Process for
Policy and Guidance
Public Comments
Federal Aviation Administration
Presented to: MARPA
By: FAA, Standards Staff, Engine and Propeller Directorate
Date: October 28, 2015
FAA Guidance
Advisory Circulars Turbine Engine and APU Parts
2 Federal Aviation Administration
FAA Advisory Circulars
October 28, 2015
New Guidance
• Materials [See previous presentation.]
• Statistics
• Geometry
• Rub Rig
• Influencing Parts Guide
Advisory Circulars
3 Federal Aviation Administration
FAA Advisory Circulars
October 28, 2015
Status: Ready for Second Comment Review
• Provides clarification for determining the appropriate sample
sizes for certification purposes
• Explains the proper use of statistical methods to show
equivalency between two populations of parts
• History
- Issued August, 2014, then withdrawn January, 2015
- Industry concerned about interpretation and applicability
- AC was revised and reviewed by MARPA (New Step)
Guidance Update (continued)
Statistics AC
4 Federal Aviation Administration
FAA Advisory Circulars
October 28, 2015
Status: Public Comment Complete
• Purpose
- Provides information about how dimensional characteristics are
affected by reverse engineering techniques
- Enhances awareness about where differences can originate in the
reverse engineering process
- Intended to supplement applicant’s ability to identify suitable
compliance methods for comparative approaches to certification
New Step - Coordinating finalized version with MARPA prior
to issuance and posting comments in the Federal Register
Geometry AC
Guidance Update (continued)
5 Federal Aviation Administration
FAA Advisory Circulars
October 28, 2015
Status: In Development
• This AC will provide information to help applicants
develop their own methods for establishing equivalence
for wear related degradation
• Unlike the burner rig, there are no standardized
approaches for assessing relative wear capability for
replacement parts
Rub Rig AC
Guidance Update (continued)
6 Federal Aviation Administration
FAA Advisory Circulars
October 28, 2015
Status: AIA Accepted FAA Tasking Letter
• The anticipated document is intended to be a
Familiarization Guide that helps applicants recognize
when their replacement part could have an effect on the
integrity of Life Limited engine parts
• How can you help?
Influencing Parts Guide
Guidance Update (continued)
Federal Aviation Administration
PMA Material Compliance Using
the Comparative Test and Analysis
Method
Presented to: MARPA
By: FAA, Standards Staff, Engine and Propeller Directorate
Date: October 28, 2015
2 Federal Aviation Administration
MARP
Draft AC 33.15-3
Objective
Provide a Methodology and Standards for assurance that the
proposed material used in PMA hardware has capability at
least equivalent to Original Type Design (OEM) material.
Verification Process
Utilizes a series of tests to define and evaluate the PMA and
OEM material and compare material capabilities.
Tests are performed according to accepted Aerospace
Standards.
3 Federal Aviation Administration
MARP
Verification Process Rationale
Based on the fundamental metallurgical principle that a material’s
capabilities (mechanical and physical properties) are controlled by
its “metallurgical properties”.
These Metallurgical properties include:
Chemical Composition
Material Form (i.e. casting or wrought material type)
Microstructure
Hardness
Surface Coating or Treatment
Draft AC 33.15-3
4 Federal Aviation Administration
MARP
Draft AC 33.15-3 Verification Process Methodology
PMA Applicant can perform comparison tests on finished PMA
parts and similar Design Type parts. This is suitable when sufficient
test material can be extracted from these.
PMA Applicant can perform comparison tests on specially prepared
test material which duplicates the metallurgical properties in the
corresponding finished parts.
If Metallurgical Property equivalence is proven, the PMA
Applicants component is equivalent to the Type Design one.
This comparative test program must be reviewed and agreed upon
by the FAA prior to execution
5 Federal Aviation Administration
MARP
Draft AC 33.15-3
If Metallurgical Equivalence is Not met
The PMA Applicant is guided through a series of mechanical
and physical properties which could affect part function. Evaluating
these properties with approved techniques would validate the PMA
Part suitability for qualification.
6 Federal Aviation Administration
MARP
Draft AC 33.15-3
This AC provides
A disciplined methodology for evaluating the capability of PMA
material relative to Type Design material
Provides standards for testing and demonstrating “equivalency”
of materials
Handles situations where material substitution occurs
Provides alternate means of compliance other that comparative
testing.
7 Federal Aviation Administration
MARP
Additive Manufacturing
• The Design, Manufacturing, & Airworthiness Division (AIR-100)
recognizes that Additive Manufacturing (AM) is a potential game
changer in the fabrication and repairs of aircraft, engine and
propellers.
• AIR-100 Issued a Memorandum requiring ACOs / MIDOs to notify
FAA of AM projects.
• AMNT is developing a checklist to provide a list of the key questions
that need to be asked when certifying a part using AM technology.
2 Federal Aviation Administration
FAA Protocol for Public Documents
October 28, 2015
Advisory Circular Review Process
• Early Notification of Guidance to Industry
• Reasons for the AC (description, applicability)
• Solicit input during document development
• FAA Internal Review and Comments
• Public Review and Comments
• Review AC Updates with Industry
• Issue Document
3 Federal Aviation Administration
FAA Protocol for Public Documents
October 28, 2015
Comment Log
Agency Disposition
4 Federal Aviation Administration
FAA Protocol for Public Documents
October 28, 2015
Potential Comment Disposition
Adopted
• FAA concurs with the comment and the suggested
changes are incorporated into the document
Partially Adopted
• Some suggested changes are incorporated into the
document or clarification is added
Non-Concur
• No changes are made to the document
5 Federal Aviation Administration
FAA Protocol for Public Documents
October 28, 2015
Potential Comment Disposition
Concur but Outside of Scope
• Comment is valid, but it affects a broader range of
Products, Regulations or Processes than intended
Answer to a Question or Statement rather than
a Comment
• Generally, questions and statements are considered as
comments and often prompt changes that clarify the
document intent and applicability
6 Federal Aviation Administration
FAA Protocol for Public Documents
October 28, 2015
Effective Comments
Examples
• Comment proposes additional considerations
that take into account specific concerns
• Comment highlights potential for unintended
consequences
• Comment explains the impact to their company,
and provides details to support the statement
7 Federal Aviation Administration
FAA Protocol for Public Documents
October 28, 2015
Ineffective Comments
• Non-specific critiques with no or little rationale
without suggestions for alternative words
– “We don’t need this AC.”
– “No testing is required for PMA.”
– “If this is true, FAA needs to issue ADs for all PMA.”
– “The engine manufacturer must provide critical design
information so it can be copied.”
• Sometimes ineffective comments support the
need for the advisory circular