Tuned up VW Engine
It so happened that a certain ultralight VW powered aircraft (Rollason Turbulent) was 'improved' for racing. On the airframe side it received some 'cleaning up' including a reduced height windscreen and spats, gap sealing etc, but, but its real 'boost' came from an engine with high comp pistons and a prop that was matched to give speed rather than climb. The end result was a machine that could exceed its vne in level flight if run flat out.
The Duke of E flew one such machine on a normal flight, and unknown at the time (and unconnected) it later broke a crank (but still landed ok).
It transpired that there was nothing wrong with the basic crankshaft, but with a lack of a flywheel there was an extra stress condition and the cast crank would start to crack from a part number marking. Later engine models started to use forged cranks and have given decades of faultless service.
The original prototype ATC Slingsby Falke was delivered with a hand pull lever starter similar to that on the RF4. The RAF were not really aware that this was normally only used for airborne starts to get over the initial compressions, and of course the engine became difficult to start on the ground, as everyone else would hand swing the prop which was a normal operation. The standard Rollason Ardem had dual ignition (with lucas tractor mags in those days) so that side of things did not help the weight especially when fitted with an impulse coupling for starting.
If we fast fwd to the present time and the Grob 2500 engine this was produced with twin carbs with a high mounting so added a complexity not present in most VW conversions as any fuel/heat/airlock situation can lead to a very uneven engine balance if both carbs are not working in harmony. An interesting potential project could be to utilise an available fuel injection system with a single fwd facing air inlet that gives an element of ram air (as per normal light aircraft situation) and also reduces the usual 'carb icing' potential. All this could be done under the LAA system and may well be a solution for the future. It is quite obvious that the basic 109 is a well proven machine, and if operated at sensible weights as designed is quite capable of launching itself without problems. It does not need an expensive re-engine program (nor a glass cockpit) to perform as designed, and having served the Air Cadets so well for its required service life it could still proceed to its next life under the LAA as have the motor Falkes.
ATC gliding is never coming back 'as was' due to many factors; the main one being crass top management. However the legacy of this volunteer training machine will always be remembered for its ability to inspire youth to achieve solo flight with minimum fuss and maximum effectiveness, and as such it had no equal anywhere in the world. Be proud for its memory.