Certification & Approval Having worked out a promising-looking layout, initial three-view and performance and weight specifications, now is the stage where the hard work begins of transforming concepts to working drawings. Essential decisions have to be made about types of material to be used, the structural arrangement, exact choice of powerplant and so on. You’ll probably need to make a cockpit mock-up to check the ergonomics and control system arrangements, and maybe build a flying radio controlled model of the design to give faith in the handling characteristics. With the basic geometry laid out, stress calculations and assembly drawings come next, then drawings of individual piece parts. Keep an up-to-date tally on weights. As the drawings get more detailed you must re-evaluate whether you are going to meet your original targets in terms of weight, strength and aerodynamic cleanliness, whether you need to re-visit your original assumptions or re-design from scratch. Is there a way that the part or assembly can be made more easily, more cheaply, lighter, stronger, more fatigue or corrosion resistant ? Fewer parts and fewer joints generally means fewer problems and less weight. Can you use off the shelf parts rather than having to make them specially ? Are there other aeroplanes around that have already solved a particular problem in a clever way ? Will the aircraft be easy to inspect in service, easy to repair if it gets damaged ? Can it be broken down for transportation ? If the handling isn’t quite right when the prototype is test flown, does the design make provision for ‘tweaks’ to put it right ? Does the design include reserves of strength to cope with weight growth in service and more powerful engines, or is everything pared down to the minimum ? Downloadable Spreadsheets Technical Leaflets Design Tutorials

Modifying & Repairing Aircraft One of the main features of the LAA system is that modifications and repairs can be approved with significantly reduced costs compared with aircraft on Certificates of Airworthiness, where applicants would need to deal with the CAA or EASA. Since the engineering team are all ‘little aircraft’ experts, it is usually a straight-forward job to approve many types of change. Of course, with many of our members being so creative, sometimes the job takes a little more time and thought to approve! View current mod/repair application queue Modifcation Type Description Further Details Application Form Application Fee Category Changes Applications to change an aircraft’s category from a microlight to a ‘Group A’ aircraft (and vice versa) are allocated a modification number to record the change. If an engine or propeller change is required at the same time, then an application must be made as noted above. N/A LAA/ MOD 10 £206 Engine & Propeller Changes These are treated as Prototype or Repeat modifications, unless they appear on the PTL list for the type. Technical Leaflet TL 3.02 LAA/MOD 4 and LAA/MOD 5 * See below Avionics Installations These are not considered modifications, but in order to fulfil their legal obligations, owners are required to keep LAA up-to-date should radio details alter. A special system exists for the approval of radio changes that is separate from other modifications. Technical Leaflet TL 3.03 LAA/MOD 7 No charge for radio/transponder installations, but a £31 fee is chargeable for certified ADS-B Out applications STCs Where a change has previously been approved by means of a Supplemental Type Certificate (STC), an LAA Inspector can sign off the change. Technical Leaflet TL 3.29 N/A N/A The Trivial Change Sometimes a change is so trivial that no application is required and there is no need to inform the Engineering department. Technical Leaflet TL 3.10 N/A N/A Manufacturers' Modifications Kit manufacturers and plans suppliers often have long lists of optional modifications that can be fitted and during the lifetime of a type product improvements are introduced. Generally, LAA-accepted optional items are listed on the TADS for the type. N/A N/A N/A The Standard Modification This is a modification that is very well defined and is applicable to a particular aircraft or engine type or types. Members may nominate new Standard Modifications using form LAA/MOD 9; however, LAA Engineering may choose to convert popular Repeat modifications into Standard Modifications. Technical Leaflet TL 3.06 LAA/MOD 1 Variable, see individual mods for details The Repeat Modification A modification that has already been approved on one aircraft as a Prototype modification. Note that a Repeat modification must identically replicate the original Prototype modification including fasteners and positions of parts and should generally be on the same aircraft type as the original. Technical Leaflet TL 3.07 and TL 3.17 LAA/MOD 11 * See below The Prototype ("normal") Modification This is a normal modification application made in the usual way and is applicable only to the aircraft for which the application is made. Technical Leaflet TL 3.01 LAA/MOD 2 and LAA/MOD3 * See below * All prototype modifications (including engine and propeller changes) attract a minimum fee of £103 which covers up to two hours' work; all repeat modifications (including engine and propeller changes) attract a minimum fee of £52 which covers up to one hour's work. Thereafter, work is charged at £57/hour in either case. See the relevant Technical Leaflet for the type of modification for further details. To access the Technical Leaflets, MOD forms and Standard Modifications described above, click one of the buttons below: Technical Leaflets on Modifications & Repairs LAA MOD Forms Standard Modifications

< Back LAA Head Office closed on Friday 4th July 3 Jul 2025 LAA HQ will be closed on Friday 4th July 2025 due to the Silverstone Grand Prix. All staff will be working from home, so can continue to deal with your calls and emails, but will not be on site at Turweston to answer any questions directly or receive any hand-delivered documents. Next Previous

LAA are proud to announce our Rally 2025 sponsors The 2025 LAA Rally will take place at Leicester Airfield over the three days Friday 29th to Sunday 31st August. We are excited to be working with Leicestershire Aero Club to host the event at Leicester Airfield. The weekend will focus on the fly-in and social elements of our annual event; provide the opportunity to see a wide range of exhibitors, hear from industry experts in our Speakers Corner programme of talks, get hands-on skills experience in the Homebuilders marquee; meet our LAA team, purchase LAA merchandise and relax in the Struts & Clubs stand. We are reverting to our traditional exhibition layout which provides for a series of marquees housing all the LAA activities; indoor exhibitor space and our homebuilders exhibits. Outside provides the space for larger displays and we will look forward to showcasing manufacturers and distributors of a wide range of the latest aircraft types from across the LAA fleet. The Speakers Corner marquee, will host a varied programme of talks throughout the weekend, including an open Q&A session each day with CEO, Simon Tilling. Members will have free access to the aircraft park, with access available at an additional charge to non-members enabling everyone to get up close to inspect the wide range of aircraft attending the Rally. The exhibition site will host a wide selection of food choices, a full bar and ice cream van during the daytime whilst evening entertainment, food and bar will be provided by Leicestershire Aero Club. There will be free car parking and on site campsite. We look forward to seeing you at Leicester! Introduction

Light Aviation Magazine 2019 Click on the links below to open each issue of Light Aviation Magazine from 2019 January 2019 April 2019 July 2019 October 2019 February 2019 May 2019 August 2019 November 2019 March 2019 June 2019 September 2019 December 2019

Night IFR Certain LAA types can be cleared for flight at night and/or under IMC (instrument meteorlogical conditions) - commonly referred to as 'Night/IFR' for convenience. The special Night/IFR requirements and process are detailed in technical leaflets TL 2.27 and 2.28, linked below, which are additional to the standard requirements applicable to any LAA aircraft. The special requirements involve the aircraft being of a type that demonstrates flight handling broadly in accordance with CS-23 subpart B (some types, including the RV-6 and RV-7, have a restricted aft cg limit to meet the pitch stability requirements), and each individual example must have a special IFR flight test to confirm it matches the first one tested. For a night clearance, the aircraft must also undergo a night test to check its lighting and general suitability for night flight. The aircraft must have accumulated enough flying hours in VFR to prove its reliability, and it must have an engine of a type accepted as being likely to be as reliable as a certified engine (for example we accept ‘clone’ Lycomings even though not certified). The propeller must be rain-proof, i.e. have hardened leading edges, and the aircraft must have an effective carb ice prevention system. The aircraft’s panel must have at least two independent attitude indicators, with either separate power sources or back-up internal power. If two EFIS are used to provide attitude information, with no other attitude instrument, then the two EFIS must be of different manufacturers so as to avoid the risk of simultaneous failures. There must be pitot heat, an alternative static and an OAT gauge. If the essential systems are relying on electrical power, the electrics must be designed to avoid being vulnerable to any single component failure, and if there is a single alternator there must be enough battery capacity to keep the essential systems running for an adequate time (at least 30 mins) before the battery goes flat. If two radios are fitted, they must not be both vulnerable to failure if any single component fails (e.g. must not be both fed through a single avionics master switch with no back-up power available). LAA does not specify what navigation or radio equipment is fitted, but as with a certified aircraft, the equipment fit determines what type of airspace can be used. An autopilot is not required, but certainly helps reduce pilot workload in sustained instrument flight. Non-certified equipment, including EFIS and autopilots, alternators, etc, are permitted, subject to the usual LAA checks. The aircraft has to be inspected initially and annually by an inspector with a special ‘night/IFR’ endorsement on their LAA inspector approval, and the aircraft is checked to have been built to an appropriate level of quality for a night/IFR aircraft. For example, quality of its instrument wiring, electrical power supply wiring, etc, are checked which are much more critical than in an aircraft only flying day VFR. The ASI and altimeter must be regularly calibrated, the battery must have a regular capacity check and the radios checked regularly by a qualified radio engineer. The aircraft must have an accepted pilot’s operating handbook and an acceptable maintenance schedule, and be maintained to that schedule. The application process involves not only a night/IFR inspector but also a night/IFR assessor who is one of a small band of LAA volunteers qualified to assess the design aspects of the aircraft’s systems and who compiles a technical report about the aircraft and if he is happy with it, includes a recommendation to remove the day-VFR only restriction. The report includes details of the aircraft’s systems, the special flight test reports, inspection reports, maintenance schedule and POH, a photo of the instrument panel and an electrical load analysis. This report is sent to LAA Engineering who checks through it and all being well, issues the aircraft new paperwork with the day and/or VFR restriction removed and replaced by limitations allowing IFR and/or night flight. All LAA night/IFR aircraft are restricted to not fly in the vicinity of thunderstorms and, for IFR cleared aircraft, take-off and landing in visibility less than 1500m is prohibited. The aircraft may not be operated in IMC below 500 ft agl for a precision approach, or 600 ft for a non-precision approach, or approach system limits, whichever is the greater. The pilot qualification for flying an LAA night/IFR aircraft at night or in IFR is the same as for flying a certified light aircraft at night or IFR. Aircraft types that have been successfully cleared for night/IFR flight include the RV-6, -7, -8, -9 and -10 (nosewheel and tailwheel variants – some with cg range restrictions), Europa and Cozy. Several of the modern lightweight 600 kg types have failed to comply due to low stability margins making them OK for day VFR flight but not suitable instrument platforms for night or IFR. Whilst a very few Rotax powered aircraft have been be to be cleared, most of the thirty or so LAA aircraft that have successfully transitioned are powered by Lycoming or Lycoming-clone engines. PROCESS SUMMARY LIST OF TYPES PERMIT IFR FEES NIGHT IFR INSPECTORS FAQs POH LITE TEMPLATE (PowerPoint File) NIGHT IFR PILOTS ACCEPTED INSTRUMENTS TL 2.27 - PROCEDURE FOR APPROVAL & TL 2.28 - ASSESSMENT OF AIRCRAFT LAA/MOD15 APPLICATION FORM

Flight Testing Aircraft The following current flight test schedules are available for printing. These schedules are subject to change at any time and without notice. Ensure that the current flight test schedule is used otherwise it may not be accepted. For this reason it is not advisable to save these document on your computer. Flight Testing Forms & Schedules Other useful documentation is as follows: TL 1.19 Initial Testing Flying Pilot Briefing for First Flight TL 2.00 Revalidating a Permit to Fly CAP 1038 CAA Check Flight Handbook TL 3.19 Auto-Pilot Flight Test Notes TL 3.22 Flight Test Reports TL 3.23 Constant Speed Prop Set-Up TL 3.25 General notes and limitations on test flights Airpseed Indicator Calibration Climb-Performance Plotter FAA Flight Testing Handbook

< Back Engineering updates in October 11 Nov 2025 The following documents have been issued/updated in the Engineering 'Info Library' during October. Continuing airworthiness information : Alert A-11-2025 - Eurostar control system rose joints Alert A-12-2025 - Aeroprakt windscreens TADS: Evektor Eurostar Vans RV-9/-9A Propeller type lists PTL/1 : Murphy Renegade 912 (new) Murphy Renegade Spirit (new) Vans RV-6 (up-issued) Next Previous

< Back Engineering updates in December 2 Jan 2025 The following documents have been issued/updated in the Engineering 'Info Library' during December. Continuing airworthiness information: Mandatory Technical Directive 07-2024 - Eurofox trim cables Alert 03-2024 - Eurostar trim cables Alert 04-2024 - Loose Rotax engines Alert 05-2024 - Rotax 900 series engines - blocked oil spray nozzle Technical Leaflets: TL 2.22 'non-type specific MPDs' TADS : Sling 4 TSi Wishing all our members a very Happy New Year. Next Previous

< Back More new LAA Inspectors - Bryn Holt & Daniel Couzens 16 Jan 2024 It is time to introduce you to two new LAA Inspectors - Bryn Holt and Daniel Couzens, who both attended an LAA Inspector Assessment Day in December, with our Chief Inspector, Lucy. Bryn is the Hangar Supervisor for Shenley Engineering at Headcorn Aerodrome. He has 20 years experience carrying out maintenance on a variety of fixed wing metal, composite and wooden airframes, supporting naturally aspirated and turbocharged Lycoming and Continental Engines, Gipsy Major and Renault 4P03 Engines. Daniel is an Aircraft Engineer based in Lincolnshire, as well as being a qualified CAA welder. The first aircraft he built was an Xair microlight. Congratulations to Bryn and Daniel! 🎊🎉 Next Previous

< Back Nick Stone appointed as the LAA's Head of Airworthiness 24 Oct 2023 The LAA is pleased to announce the appointment of Nick Stone as the LAA’s Head of Airworthiness. Nick brings a vast wealth of aircraft knowledge as well as a real world understanding of the need for good process and procedure. Having started his career in the Royal Air Force, Nick went on to work in the aerospace industry working in the UK with British Aerospace and Slingsby Aviation at various sites and projects, as an inspector, methods engineer and quality engineer. Nick then moved to the United States at Eastern Airlines in Miami Florida, Learjet in Wichita Kansas and Chihuahua Mexico as inspection/Quality representative of Shorts Aerospace (Bombardier Aerospace). Following a downturn in the British Aerospace industry he then took an opportunity to move into the nuclear industry working in both reprocessing and power generation. Throughout Nick's working life the one constant has been a passion for aviation. Having started as a volunteer at a local aircraft museum at 14, Nick started flying at the age of 16 in gliders and has a private pilot’s licence PPL(A). Prior to becoming an LAA inspector Nick spent many years building, rebuilding, and restoring vintage aircraft, the more unusual the better. “As an LAA inspector I understand the need to move forward and change and adapt to an ever changing but exciting world. Having run my own aircraft restoration company for the last seven years I always felt it is important to understand your customers”. LAA CEO Simon Tilling said, “Nick is a great addition to the LAA staff. I and the rest of the team are looking forward to working with him in the near future” Next Previous

< Back Advanced LAA Rally Camping Permits - Now closed. Camping permits can be bought onsite. Camping passes, which cover the duration of your stay, are available to purchase on arrival at a cost of £65. Camping facilities, providing basic amenities, including hot showers will be available on site. There is ample ground for caravans and mobile homes. The campsite will be open from midday Thursday 28th August and close on Monday morning 1st September. Please note entry to the Rally Exhibition Site is charged separately. Prices are for the duration of your stay. On site catering and bar will be available in the Exhibition area during event opening hours and evening food, bar and entertainment will be provided by Leicestershire Aero Club in the evenings. Next Previous