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What are these EASA Acronyms?

C

Catnap

#1
STC’s –v- E-STCs
PMAs
TCs
TSOs –v- E-TSO
E-STC –v- Minor Mod

I would be really grateful for any assistance with what these actually are and the differences between them - thank you! :)
 
Last edited by a moderator:

Jim Wynne

Staff member
Admin
#2
Re: Can anyone help me with what these are please?

STC’s –v- E-STCs
PMAs
TCs
TSOs –v- E-TSO
E-STC –v- Minor Mod

I would be really grateful for any assistance - thank you! :)
Welcome to the Cove. :bigwave:

While someone here might recognize those things without it, some context would be helpful. Where did the abbreviations come from and what do they apply to?
 

harry

Super Moderator
#3
Re: Can anyone help me with what these are please?

Seems these are related to EASA (European Aviation Safety Agency)

PMA - Parts Manufacturer Approval

TSO - Technical Standard Order

STC - supplemental type certificate

TC - Type Certificate
 
C

Catnap

#4
Re: Can anyone help me with what these are please?

Sorry - this is in context with EASA Part 21.
 
C

Catnap

#6
Re: Can anyone help me with what these are please?

Thank you all :)

I have tried reading the regs but I am just not clear about what they are exactly and when they would be used.
 
M

maozetung

#8
Re: What are these EASA Acronymns?

[FONT=&quot]Dear Catnap, in an attempt to give you help I tried to summarize the basics information you requested. Since I work in EASA environment, I have a limited knowledge of the FAA system then, if you need to go deeper, I suggest you to move to more competent persons in FAA field for all related matters. Please find below my answer:[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]Supplemental Type Certificate[/FONT][FONT=&quot] provides approval of major changes to the type design developed by a design organization other than the Type Certificate Holder. I.e. if you intend to install a swimming pool or a bowling alley on your Airbus A330, as long as such modifications are not covered by an Airbus Modification, you have to seek for a Design Organisation approved under Sub J which has entered into an arrangement with the type-certificate holder and has developed a major changes to the type design and the type-certificate holder has advised that it has no technical objection.[/FONT][FONT=&quot][/FONT]
[FONT=&quot]As long as an STC is not needed for minor changes to the type design there is no relationship between them.[/FONT][FONT=&quot][/FONT]
[FONT=&quot] [/FONT][FONT=&quot][/FONT]
[FONT=&quot]PMA (Parts Manufacturer Approval) [/FONT][FONT=&quot]is a combined design and production approval, under FAA rules, for modification and replacement articles. It allows a manufacturer other than the OEM (Original Equipment Manufacturer) to produce and sell these articles for installation on type certificated products. The PMA system allows for demonstration of compliance of the article with the applicable airworthiness standards under the “identicality principle” (usually for articles produced under licence agreement from the FAA Design Approval Holder). ref. FAA Order 8110.42 at latest revision.[/FONT][FONT=&quot][/FONT]
[FONT=&quot]PMA parts may be parts needed to embody an STC. In Europe PMA parts are eligible to be installed on EU Type Certificated products provided that:[/FONT][FONT=&quot][/FONT]
·[FONT=&quot] [/FONT][FONT=&quot]The PMA part is not a critical components, or[/FONT][FONT=&quot][/FONT]
·[FONT=&quot] [/FONT][FONT=&quot]It has Produced under licensing agreement from the FAA design approval holder, or[/FONT][FONT=&quot][/FONT]
·[FONT=&quot] [/FONT][FONT=&quot]It is needed for a design change or STC.[/FONT][FONT=&quot][/FONT]
[FONT=&quot]
[/FONT]
[FONT=&quot]Refer to EASA policy in ED Decision 2007/003/C for more info.[/FONT][FONT=&quot][/FONT]
[FONT=&quot] [/FONT][FONT=&quot][/FONT]
[FONT=&quot]Type Certificate [/FONT][FONT=&quot]is the design approval issued by EASA to aerospace manufacturers after it has been established that the particular design of a civil aircraft, engine, or propeller has fulfilled the applicable regulatory requirements. The type-certificate covers the product, including all parts and appliances fitted thereon.[/FONT][FONT=&quot][/FONT]
[FONT=&quot] [/FONT][FONT=&quot][/FONT]
[FONT=&quot]ETSO[/FONT][FONT=&quot] (European Technical Standard Order) authorisation represents one way to have parts and appliances approved. This is an optional step which ensures that a part or appliance complies with a minimum performance standard. European Technical Standard Order authorisations are covered by Subpart O of Part-21 which is the Annex to Regulation 1702/2003.[/FONT][FONT=&quot][/FONT]
[FONT=&quot] [/FONT][FONT=&quot][/FONT]
[FONT=&quot]ETSO are usually designed under Alternative Procedures to Design Organisation Approval (ADOA).[/FONT][FONT=&quot][/FONT]
[FONT=&quot] [/FONT][FONT=&quot][/FONT]
[FONT=&quot]Under the FAA system, the Technical Standard Order (TSO) is one of the procedures the FAA uses to establish standards for aircraft parts. TSOs have been established for many types of aircraft parts such as engines, landing gear parts, environmental system components, and many avionics.[/FONT][FONT=&quot][/FONT]
[FONT=&quot]If there are no TSO categories established for the part that the manufacturer wants to sell, the manufacturer can still get FAA approval by testing the part in the actual aircraft type where it is to be used. To accomplish this, the part must first be conformed to the design drawings by a FAA-designated inspector to insure it meets type design. Then it will be installed and tested in accordance with a FAA-approved test plan. Upon successful completion of the tests, submittal of the appropriate documentation, and verification of a FAA-approved manufacturing system for the part, the FAA will issue a letter identifying the part as eligible for installation under PMA for the specific airplane type in which it was tested. The PMA part may then be installed in the aircraft via STC or TC.[/FONT][FONT=&quot][/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]Regards[/FONT]
 
C

Catnap

#9
Re: What are these EASA Acronymns?

Thank you very much - I really appreciate it :)

Can anyone tell me why an ETSO would be preferred over an STC?
 
H

HankMoody

#10
Re: What are these EASA Acronymns?

Hey Catnap,

I guess the main difference is that a STC is not for a single part, a STC can e.g. cover the complete interior of a business jet (if everything is modified and personalized).
But you could additionally get an ETSO for every single part of that same modification, e.g. every screw, hinge, display, etc.

I worked 7 years as a Powerplant Engineer for an international commercial airline based in middle europe and I never came across the Term ETSO. But engines are not often modified by an operator himself (as against the passenger cabin for example) so all parts you are replacing/repairing/inspecting are from the OEM of the engine and described in the manuals.

Best regards,
Hank
 
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