Avgas UL91 & UL94 UL91 has been supplied at many airfields for a number of years. UL94 (similar to UL91 but with a slightly higher octane rating) is now becoming available. These fuels are suitable, and approved, for a wide range of engines types used in LAA aircraft. With 100LL being phased out over the coming years, now is an ideal time to see if your engine is compatible and help do your bit for the environment. The LAA Airworthiness Approval Note (AAN) for use of UL91 & UL94 in appropriate LAA aircraft can be found here . It contains a list of the most popular types of engines for which the fuel is suitable. The EASA document pertaining to use of UL91 in non LAA types is available here.

Rotax Fuel Injected 912 iS / 915 iS Installation & Operation Price Member - £216, Non-Member - £236 Duration Arrival 09:30. Finish 17:00. < Back About the Course With the growth of interest in the fuel-injected Rotax 912 and 915 iS series engines, it has become apparent that there is a lot of confusion and misunderstanding about the installation and operation of these engines and the way that the latest built-in systems work. Electronics and Rotax iRMT certified engineer, John Barrott, was an early installer of a 912iS and found it difficult to find accurate information on best practice. Working with UK Rotax agents CFS and LAA Engineering, John has built up a comprehensive understanding of the iS engines and has developed a course around this to provide help and advice on the installation and operation of this new generation of aero engines. The course is classroom (not workshop) based. Your Instructor John Barrott Dates Saturday 21 February 2026 Times Arrival 09:30. Finish 17:00. Duration One day course Venue LAA HQ, Turweston Aerodrome, NN13 5YD Price Member - £216, Non-Member - £236 Booking Pls call the LAA on 01280 846 786 to enquire/book or email [email protected] . *Please note that payment is required when booking, to confirm your place. NO place will be held without confirmed payment* **Please note that your booking payment is non-refundable unless we can fill your place timeously or there are exceptional circumstances**

Caring for your Gipsy Major - Basic Course Price Member - £206, Non-Member - £226 Duration Arrival 09:45. Finish 17:00. < Back About the Course Caring for your Gipsy Major course presented by acknowledged DH Gipsy engine aficionade, Dennis Neville. Dennis will explain the ins and outs of these vintage aircraft engines and solve those starting difficulties. Your Instructor Dennis Neville Dates New date TBC Times Arrival 09:45. Finish 17:00. Duration One day course Venue LAA HQ, Turweston Aerodrome, NN13 5YD Price Member - £206, Non-Member - £226 Booking Pls call the LAA on 01280 846 786 to enquire/book or email [email protected] . *Please note that payment is required when booking, to confirm your place. NO place will be held without confirmed payment* **Please note that your booking payment is non-refundable unless we can fill your place timeously or there are exceptional circumstances**

Preliminary Design Preliminary Design is the stage where the design is sized and developed in outline, leading to a three view drawing, performance and weight predictions. To help with this, LAA has developed a number of spreadsheets. Spreadsheet 1 is used to develop the basic geometry of the proposed aircraft, size the wing, fuselage and tail surfaces and work out some of the key parameters used later. Spreadsheet 2 is used to estimate the performance of the aircraft based on the geometry, initial weight estimates, engine power and guestimates of the drag coefficient and prop efficiency, allowing you to see how the performance is affected by changing each parameter in turn. Spreadsheet 3 is used to work out the critical structural speeds, develop the flight envelope and predict the aerodynamic loads on the main surfaces which can be used to size the structure, and as the basis for a load test program. The weight and balance spreadsheet elsewhere on our website allows the designer to quickly evaluate the implications on weight and cg of different positions for the crew, fuel tanks and baggage bay, and work out what empty aircraft weight and cg he must aim for. Thanks to the simplicity of these programs it takes only minutes to study the implications of changing the aircraft’s specification, for example the effect of changing the wing aspect-ratio, the trade-off between extra weight and cleaning up the airframe drag, extra power etc. Downloadable Spreadsheets Worked Spreadsheet Examples Design Tutorials

Engineering INFO LIBRARY CONTINUING AIRWORTHINESS INFORMATION INSPECTOR ZONE FLIGHT TESTING AIRCRA FT NIGHT/ IFR REVALIDATING A PERMIT TO FLY TECHNICAL LEAFLETS OPERATING & MAINTAINING BUILDING AIRCRAFT MODIFYING & REPAIRING AIRCRAFT FIND AN INSPECTOR TADS ENGINEERING FEES DESIGNING AIRCRAFT BUYING AIRCRAFT

97 Octane Super Unleaded Since the replacement of regular E5 Mogas at the pumps by E10, for the time being at least, Mogas users have an alternative option in the form of 97 RON Super Unleaded fuels. 97 RON Super Unleaded fuel supplied by garage forecourts is NOT necessarily ethanol-free, but its ethanol content will be capped at a maximum of 5%. 97 RON E5 Super Unleaded fuel can be used under the LAA process for E5 Mogas, as before. There’s currently no legal requirement for ethanol to be present in super unleaded petrol and in fact, quite a few members have reported that their tests have shown Super Unleaded fuel to be ethanol-free in their areas. Esso reports that “Synergy Supreme+ 99 is actually ethanol free (except, due to technical supply reasons, in Devon, Cornwall, North Wales, North England and Scotland). Legislation requires us to place E5 labels on pumps that dispense unleaded petrol with ‘up to 5% ethanol’, including those that contain no ethanol, which is why we display them on our Synergy Supreme+ 99 pumps”. Shell, BP, Tesco and other fuel suppliers don’t commit to such detail, merely stating their fuels “may contain up to 5% ethanol”. Of course, many LAA members have been using Mogas of one sort or another for many years. For many airstrip users, the prospect of having to go to an airfield to fill up with Avgas would seem at best very off-putting, and at worst totally impractical for their style of operation. Hopefully Super Unleaded will continue to be an option using the LAA’s E5 procedure. Where 97 octane E5 super unleaded can be found that’s ethanol-free, it can be used in the broader range of LAA aircraft with engines eligible for use with E0 unleaded fuel. But it is important that Mogas users take on board the fact that unlike with aviation fuels, automotive fuel specifications generally only describe the properties of the fuel blend, in terms of octane rating and other characteristics, they don’t specify the chemical make-up of the fuel. Apart from specifying broad maxima and minima for those components that the powers-that-be wish to either encourage or discourage, the specifications leave to the fuel supplier the choice of how to blend the fuel to achieve the described properties. In some cases it’s the relatively small amounts of additives that cause compatibility issues, rather than the main components of the fuel that cause the problems – and the mix of additives may vary from one batch to the next. With Mogas of any type, what you get from the pump one week may be different to what you get the week after, or got the week before. The fact that your fuel system pump diaphragms, seals, composite tanks and so on might have been unaffected by Mogas up till now does not guarantee that they will be OK with the blend that the next tanker-load brings to your garage forecourt. Unfortunately there is no simple answer to this, and the only way to mitigate this problem is by constant vigilance, and thoughtful adaption of your maintenance schedule to check for signs of problems developing before they create a safety issue – more frequent checking of filters, changing of fuel lines etc. Signs to watch out for are swelling of rubber components like diaphragms, fuel valve seals and O rings, fuel pipes hardening or developing surface cracks, fuel tank sealants wrinkling or detaching from the internal surfaces of fuel tanks. Varnishes on cork floats may go gummy, or plastic carburettor floats absorb fuel and lose buoyancy, causing a rich mixture and rough running. Watch out for discolouration of the fuel you take out as fuel samples, which may imply something dissolving somewhere in the system, and for corrosion in the bases of your carb float bowls and gascolator. Avoid letting Mogas go stale in your fuel system – drain it out before a long period of disuse. Don’t leave the tanks empty for a long period – better to fill them with Avgas which will reduce condensation, and also, particularly with plastic tanks, prevent the tank’s internals drying out which can cause problems with shrinkage, and in extreme cases, the tanks splitting open. O rings and other rubber parts are best kept submerged in fuel continuously. We’ve seen cases where composite aircraft skins have rippled apparently due to exposure to the vapours created by the break-down products in stale Mogas, after being left unattended over a single winter. Mogas is blended with the expectation that in a car it will be used within a few weeks of being supplied, so it doesn’t need to be as stable over a long period of time as an aviation fuel. If a composite or plastic fuel tank is built into your aircraft, consider carefully whether you want to run the risk of having to replace it should the tank deteriorate with Mogas exposure, with all that that implies. With an integral tank in a wet-wing Jabiru aircraft, the answer should be certainly not – but even with the embedded polyethylene fuel tank in a Europa’s fuselage, changing the fuel tank is not an operation for the faint-hearted, involving cutting out quite large parts of the fibreglass cockpit module to release the tank, and then scarfing them back again afterwards in-situ. The Europa kit was first produced in the era of four-star Mogas, a very different blend to what we find at the pumps today. Ethanol-proof rubber hoses are available. In particular SAE J30/R9 or the European equivalent DIN 7339 D3 are automotive hose standards that are widely available from auto factors, and should be used in preference to the older SAEJ30/R6 standard hose which is more permeable to fuel vapour and will more quickly harden and crack, particularly using fuel containing ethanol. The SAE spec J30/R14 is a lower pressure, more pliable version for carburettor systems. Watch out for cheap imitations – the real McCoy should come from a reputable manufacturer, be marked with the SAE number along its length and will likely cost at least £10 a metre. What can we do to help the situation ? It may be that off-the-shelf drop-in-the-tank additives can be used to mitigate some of the problems with mogas fuel, in particular, stabilisers and anti-corrosion products, just as they are routinely in the marine and race-car world. Not knowing what’s in them, we recommending steering clear of any additives that claim to boost the fuel’s octane. Definitely avoid additives that claim to actively enhance an engine’s power or fuel economy, other than just to restore proper performance by giving the carburettor jets and orifices an occasional clean-up. For most aircraft engines UL91 Avgas remains the ideal fuel, in that it is a tightly-controlled aviation-grade fuel of a guaranteed composition, blended for long-term stability and optimal volatility for aviation use. As it is in effect the familiar 100LL Avgas but supplied without its tetraethyl lead, any fuel system designed for 100LL Avgas will be unaffected by using UL91 fuel, or, if circumstances demand, by a mix of 100LL and UL91. Despite a pervasive mis-conception, UL91 fuel is NOT Mogas and suffers from none of the issues associated with Mogas use in aircraft. A list of engines suitable for use with UL91 fuel can be downloaded from the ‘operating and maintaining an LAA Aircraft’ page of the LAA’s new website. Moves are afoot to increase the number of airfields supplying UL91 fuel, with full LAA backing.

For part-built LAA projects, the new owner/builder needs to continue following the LAA amateur-build process. For already-flying LAA aircraft, the new owner simply takes on the responsibilities of the old owner for looking after the airworthiness of the aircraft. The restoration of an aircraft might range from dusting off the cobwebs and giving the engine a good service, to a full strip down to component parts and fabricating missing or damaged parts. It is also possible, in some circumstances, to import a part-built or completed aircraft from overseas. This is generally only possible where the type is already accepted by the LAA, the aircraft can be shown to have been amateur-built under a similar regime to that in the UK, and which is readily inspectable to confirm the build standard. A number of LAA types come under the heading ‘orphaned vintage types’. These are types that are no longer supported by their manufacturer and have been deemed ‘orphaned’ by the CAA (e.g. Austers). There are also some types that can elect to operate either on a Certificate of Airworthiness or on an LAA-administered Permit to Fly (e.g. Chipmunks). Buying an Aircraft Not everyone has the inclination, ability or time available to build an aircraft. The only route then is to buy a part-built aircraft for completion, a ready-flying aircraft or an aircraft in need of restoration. When buying an aircraft, the overriding message is ‘Buyer Beware!’ If you’re buying an aircraft that is already flying within the LAA system, you mainly need to satisfy yourself that it’s in an acceptable condition and meets your needs. LAA Inspectors are often happy to look over an aircraft for you to help you make a technical assessment of its condition. Another area you should consider is whether it has enough payload to take you where you want to go. When buying a partially-built aircraft or one from overseas, you need to make sure that the aircraft is eligible to hold a UK Permit to Fly and is in a configuration that the LAA can accept. It is usually a good idea to drop LAA Engineering an email to check before you part with large amounts of money. For further information, click the button below or look in the 'Classifieds' section of the LAA Magazine Click here for more information

LAA are proud to announce our Rally 2025 sponsors Opening Times & Car Parking Opening Times Visitors will be asked to leave the exhibition area by 5.00 p.m. Friday: 9.30 a.m. to 5.00 p.m. Saturday: 9.30 a.m. to 5.00 p.m. Sunday: 9.30 a.m. to 4.00 p.m. Car Park Car parking remains free. Follow sign posts to visitors car park. Please do not use the Exhibitor car park. Disabled parking is available. Please note that entrance to the LAA Rally car park and exhibition site is separate from the Leicestershire Aero Club entrance (reserved for LAC members and other airfield users) How to get there Leicester Airfield , Gartree Road, Leicester, LE2 2FG Follow the Rally Car Park Signs What3words Location: rings.using.nails

Light Aviation Magazine 2022 Click on the links below to open each issue of Light Aviation Magazine from 2022 January 2022 April 2022 July 2022 October 2022 February 2022 May 2022 August 2022 November 2022 March 2022 June 2022 September 2022 December 2022

For Single Engine Piston Assistance (SSEA) Tel: 01280 846 786 - LAA [email protected] For Self Launching Motor Glider Assistance (SLMG) Tel: 0116 289 2956 - BGA [email protected] For Microlight Assistance (M) Tel: 01869 338 888 -- BMAA [email protected] Applications received by the LAA Please allow 5 working days for your SSEA / SLMG application to be processed by the LAA. If you wish to check on the progress of your application, look at the Current Applications Page or contact LAA on 01280 846 786. For the issue of your licence contact CAA licencing department on 01293 567 171 Website links: LAA - BMAA - BGA -CAA Help and Contacts

< Back The New Permit Revalidation System - Step-by-Step Guide 9 Apr 2025 The new LAA Permit to Fly revalidation system will go live on 15th April 2025. This streamlined, fully online process offers an easier and faster way for aircraft Owners and Inspectors to handle Permit to Fly revalidations. Watch this video for a step-by-step guide on how to complete the online Permit Revalidation process, both as an Owner and as an Inspector. There are a few key considerations to ensure your revalidation under the new system goes smoothly: Please make sure you know your username and password before applying for your aircraft’s revalidation. If you have forgotten your login details, please contact the LAA Office. All aircraft using the new system for the first time will require a check flight no older than 3 months at the time you submit the revalidation application. This is in order to provide a baseline for the online system. The 3-year check flight schedule will then apply subsequently to most aircraft types. Some aircraft will still require a check flight at every revalidation, these are: Aircraft cleared for glider tugging in their Operating Limitations document. Aircraft cleared for Night/IFR. Aircraft which have flown less than 12 hours since the previous revalidation inspection. You will not have to submit your CFS-1 Check Flight Schedule when applying through the new system. However, a CFS-1 will need to be completed for each check flight and stored with the aircraft’s documentation, so that it is available when needed. We encourage you submit your revalidation application through the new online system, as processing time is expected to be faster than an ‘old-style’ revalidation. If you still wish to make an ‘old-style’ application up until 15th May 2025, all 3 forms must be submitted by this date and you will only transition to the 3-year check flight schedule after your first revalidation through the new system. Note: The option to apply for revalidation in ‘My Aircraft Data’ on the LAA website may appear shortly before the go-live date on 15th April 2025 as our IT infrastructure is updated. However, we will only be able to process applications received on or after the official go-live date. A handy list of 'Frequently Asked Questions' is available below: 20240409 - Permit Revalidation Process FAQs V1.0 .pdf Download PDF • 175KB Next Previous

< Back Alert A-06-2025 - Christen Eagle II Canopy Detachment 12 Jun 2025 LAA Alert A-06-2025 - Christen Eagle II Canopy Detachment LAA Alert A-06-2025 has been published on the LAA website (and is also attached), highlighting a recent Christen Eagle II Canopy detachment in flight due to damage of the canopy locking pin brackets, which were bent as a result of draught excluding foam being installed at the front edge of the canopy, placing excessive force on these brackets, so that they deformed. A-06-2025 - Christen Eagle II Canopy Detachment .pdf Download PDF • 474KB Next Previous