Permit to Fly UK CAA

Approval of Flight Conditions & Permit to Fly

STC21 is equipped to provide all necessary Flight Conditions and Permit to Fly approvals in support of your STC project flight testing. We will also coordinate and secure any required overflight permissions.

Permit to Fly UK CAA

Why Choose Us?

Our team of seasoned staff members and test pilots ensures the safest possible flight by creating detailed flight conditions and limitations, supported by thorough risk assessments, and selecting competent crew and meticulous flight planning.

Should your aircraft be grounded and require a ferry flight, STC21 is ready to assist in safely transporting your aircraft back to your chosen maintenance base.

permit to fly uk caa why choose us
permit to fly uk caa services approvals

Permit to Fly UK CAA

Streamlined Flight Readiness

Acquiring flight conditions and a permit to fly is straightforward with our web-based portal. This allows CAMO, Flight Operations, or Maintenance Operations personnel to upload pertinent data, which our engineers will promptly review and process to generate the necessary flight conditions and permits to fly, ensuring your aircraft returns home safely.

Flight Conditions and Permit to Fly approvals are also available for your research and development flight tests or maintenance check/authority acceptance flights, especially in instances where an Airworthiness Review Certificate (ARC) has expired and the Certificate of Airworthiness (C of A) is no longer valid.

Additionally, we provide direct access to pilots with CAT1 test pilot ratings for both fixed-wing and rotary-wing aircraft, enhancing the safety and versatility of your flight operations.

Permit to Fly UK CAA

Contact Information

For more information or to arrange a meeting with our expert team, don’t hesitate to reach out.

Feel free to give us a call at +44 (0) 1332 576830

or send us an email at

You can find us at 1290 London Rd, Alvaston, Derby DE24 8QP

We’re here to assist you with any enquiries or requirements you may have. Your journey starts with a simple conversation. Contact us today.

Structural Modifications

STC Twenty One, your trusted partner in aviation engineering, is dedicated to elevating safety and performance, offering a pathway to aviation's future with expertise and innovation.

Electrical Modifications

Our electrical systems services prioritise flight comfort, control and safety, offering meticulous scrutiny and assessment of everything from in-flight environment to fire protection systems.

Avionics Modifications

Digital flight control systems are the cornerstone of precision, handling autopilot, altitude control and more to ensure a safe journey. Communication, electrical power, recording systems and navigation play vital roles in maintaining aircraft performance, safety and efficiency.

Environmental Control Systems (ECS) Modifications

The air conditioning and pressurisation system maintains comfort, ice and rain protection systems prevent ice accumulation, oxygen systems ensure safety, and the water and waste system promotes cleanliness and passenger comfort.

Cabin Related Modifications

The passenger compartment prioritises comfort, convenience and safety, complemented by fire protection, cabin enhancements, avionics support in cargo compartments and essential placards and markings.