STC Twenty One can provide a large variety of modifications for aircraft and rotorcraft avionics systems for single bespoke VIP changes or fleet wide solutions. Whether it is a single aircraft or for a fleet.
Avionics Systems / Electrical
Why Choose Us?
The Avionics and Electrical team are experienced enough to meet all of your aircraft requirements but small enough to care and react quickly to ensure your aircraft remains operational.

Avionics Systems / Electrical
Services & Approvals
We offer solutions for a large format of flight navigation and communication systems, including the modification of primary instrumentation.
Keeping an aircraft flying longer in untested operational conditions is increasingly challenging. Our monitoring solutions allow for real operational data to be gathered and verified for continued airworthiness. Full access allows our customers to remove any implementation delays and achieve return on investment ahead of schedule with access to responsive hardware and our team of experts.

Avionics Systems / Electrical
Speak To The Team
Providing acceptable methods of compliance for the certification, airworthiness, and operational approval of aircraft surveillance systems and their associated aviation applications. We offer specific guidance in obtaining approval for the installation and operation of technologies, continues airworthiness and operational approval. For more information, get in touch with our lead avionics engineer.
UK CAA Approved Design Organisation
STC Twenty One
All aircraft modifications and aircraft repairs are managed by our UK CAA approved Design Office represented by STC Twenty One (UK.21J.0198).
What We Offer
Services
STC Twenty One Limited holds a Part 21 Subpart J DOA enabling it to certify UK CAA approved STCs and Major Repairs. Additionally, where a design change or repair is classified as minor, STC Twenty One Limited is authorised to approve them under the DOA using approval reference UK.21J.0198 through CAA.
Our employees are spread across our Avionics, Mechanical, Quality and Commercial Teams with a high level of experience and certification enabling the company to perform specialised services on engines and aircraft. Read more about our Services.