Leading Solutions for Aviation Industry
Innovative designs, certifications, and consulting for global aerospace needs.
We are DOA
S4A is the first company in Spain granted as Design Organization by EASA.
Most relevant STC’s
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Explore our catalogue of STC’s, Supplementary Type Certificates that transform your needs into certified solutions.
Aircraft Modifications
Our expertise lies in designing and certifying both minor and major (STC’s) aircraft modifications. STC’s are certified by EASA and may be validated by other authorities (FAA, etc).
Aerospace Testing
A history of excellence in producing comprehensive test plans, procedures, and execution for aerospace industry needs.
Aircraft Repairs
Expertise in designing repairs for both metallic and composite materials, covering structural damages, as well as functional and decorative aspects.
Turnkey Aviation Projects
Comprehensive solutions from design, installation, to global certification of aircraft repairs and modifications.
Mastering EASA/FAA validations
We expertly navigate the cross-approval of aircraft modifications, ensuring your FAA-approved changes are EASA-validated, and the other way around. By customer’s request, our modifications can be certified in front other certification authorities (Transport Canada, Bermuda, Isle of Man, San Marino, etc)
Aerospace Consulting
Offering time-bound or ongoing aerospace consulting by a dedicated team of industry experts.
Excellence in aeronautical engineering
Projects Delivered
Satisfied Clients
If you want to enjoy the advantages of S4A,
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MORE THAN 380 CUSTOMERS TRUST US
our approvals
EN ISO 9001 – Quality Management
EN 9100 – Aerospace Standards
EASA Part 21J DOA – Trusted Certification
Approved
EASA
From
Engineers
Customers
Projects carried out
Aircraft models
We deliver projects in more than 50 countries
Values that set us apart.
Price
We strive every day to offer more competitive prices.
Speed
Our team manages military deadlines and ways of working.
Flexibility
We adapt all our work to the client’s needs.
Turnkey projects
From design to manufacture and installation.
Close and decisive
Whenever you need us, we will be there regardless of the time or day of the week.