leburg.com
Leburg Electronic Ignition for Light Aircraft
About
What is the Leburg system?
It is a solid state ignition system that uses modern electronic components and is suitable for most aero engines. It is designed for builders of homebuilt aircraft, in that it is easy to install and is light and economical.
It is sophisticated in that it produces a high energy spark at the optimum point in the combustion cycle for the instantaneous engine speed. This produces the maximum power for minimum fuel consumption and the engine runs noticeably smoother. It has no moving parts and so there is nothing to wear or adjust
Whilst sophisticated in its operation, the Leburg system is based around providing a simple 'fit and forget' dual ignition system.
The Leburg system produces very gentle but effective starting characteristics, hot or cold, by boosting further the normally high spark energy and retarding the firing point to 3 degrees AFTER TDC. This makes backfires impossible, and hand propping becomes pleasant, easy and safe. These characteristics are retained for engines equipped with starters, with the further advantage that starting becomes instantaneous, which as well as being convenient, eases the load on the starter and battery.
The system is being used on many aero VW's , both 4 cylinder and 2 cylinder, with great success. It is also being used on a Subaru, KFM's and a C65. Increasingly, owners of "proper "aero engines are replacing the magnetos with the Leburg system to overcome starting problems. They report additional benefits of smoother running, steadier, slower idle, and lighter weight. Some users also report increased static revs.
Each Leburg controller drives one automotive Ford coil, which drives 4 plugs. Such modern coils produce very high voltages so that even when the plugs are dirty and fouled with fuel, oil or water, they still produce high energy sparks. An indication of this is the fact that the plug gaps are set to 0.9mm rather than the 0.4 mm used by magnetos.
One controller weighs 280g, and one Ford Zetec coil weighs 960g. The more expensive Ford Visteon coil weighs 650g.
This system is in common use today in the UK, the US and Finland. We have enthusiastic reports from users, and reliabililty is proving good.
The main features of the system are:
| * | when starting, a hefty spark occurs 3 degrees AFTER TDC. This gives gentle but immediate starting, hot or cold. If you are are hand propping, you don't need to swing the prop hard. A gentle, clean pull through TDC will do it. |
| * | when running, the spark occurs at the optimum advance angle for the instantaneous RPM. This gives smooth running and maximum available power at all RPM |
| * | there is nothing to wear, so maintenance is minimal |
| * | the system is dualled for safety. In normal use power for both ignitions is supplied by the alternator. The batteries supply power for starting, running at low revs, and when the alternator fails. The (2.3Ah) backup battery supplies power for 7 hours of running. |
| * | it is light and compact - one controller weighs 280g and one Ford Visteon coil weighs 650g. |
A welcome and acceptable modification
The Light Aircraft Association is very careful about accepting new equipment, but now that the many users
of the Leburg system have good experience with it, the LAA supports users who wish to install the Leburg system.
The minimum required by the LAA for any significant engine modification is that new users have their installation approved
by a LAA inspector and complete a ground run of 5 hours.This is all that is required for the Leburg system also.
Alternator and dual power supplies
For dual systems a backup power supply is needed. This is arranged by having two separate batteries, a main and a backup. The main battery is the one fed by an alternator, if you have one, and as well as feeding the ignition system, it also supplies the radio, GPS, and strobes etc. The backup battery is small, say 2.3 Ah and is fed from the main system through a backup diode and a circuit breaker. This provides full protection should a power failure or short circuit occur on either system.
A 2.3 Ah backup battery provides power to keep the engine running for about 7 hours, should the main system fail. In normal use, the alternator supplies power to both ignition systems, and both batteries are being trickle charged.
Having an alternator is desirable in that it provides the power to borh ignition systems while running, and it keeps both batteries fully charged without operator intervention. The batteries are then only required to give energy for starting and slow running, and they generally have an easy life. If you wish to install an alternator, an excellent yet light ( 2.2kg, 4.8lb) alternator can be made using parts salvaged from a Honda CBR600 motor cycle. This alternator supplies about 12A at 12V at 2,500 RPM. This is probably the lightest, cheapest and best quality alternator package available.
The system is installed on the following aircraft types:
Turbulents, VP1s, Taylor Monos, Nippers, KR2, Colibri, Cygnet, Jodel D9, Jodel D18, Flitzer, Sonex, BP1 Biplane, Kitfox, Scamp, LEU, Nieuport, Leburg Sparrow.
The system is installed on the following engines:
VW (4cyl), VW (2 cyl), KFM, Subaru, Continental C65
The system is in use in the following countries:
UK, USA, Australia & Finland