Neil Williams died on 11 December 1977 while ferrying a CASA 1.111 (Spanish built Heinkel 111 with Merlin engines) from Spain to England. He ran into a mountainside in poor weather North of Madrid. His last article before his passing was written for Pilot magazine and was titled "Flying the Bücker Jungmann". It is a delightful article which you can read in full here.
He has a lot to say about the Jungmann landing gear in particular (reproduced below). Much is clearly well informed while some other of his observations seem to me a bit off base, possibly because no two aircraft seem to behave exactly the same. Let's not let the facts spoil a good story though :) - What happened to those "two small links"? I have never seen reference to them anywhere other than this article.
Flying the Bücker Jungmann (extract)
The Jungmann is fitted with a tailwheel lock, and a large notice proclaims the necessity of making sure that it is locked before taxi, take-off, or landing. This is quite an essential procedure, as some of the ferry pilots had found to their cost. Out of nine Jungmanns which started out from Spain, only six reached France intact. On a grass airfield, into wind, the Jungmann is quite a docile and well-behaved aeroplane: on a runway with a crosswind it is a very different story; the aeroplane seems bent on self-destruction. Strangely enough the Jungmeister supposedly the more advanced aeroplane - is quite straightforward, and doesn't have the same tendency to swing. When one compares the two machines one obvious point emerges: viewed from dead ahead, the wheels of the Jungmann appear 'toed in', while those of the Jungmeister are straight. Combine this feature with the Jungmann's long-stroke soft undercarriage, and all becomes clear.
If a wing starts to lift, even very slightly, the weight of the aircraft is transferred to one side, and the oleo is compressed. The angle at which the wheel is set has the effect of oversteer, and initiates the swing. This is the point at which the pilot, used to harsh corrective measures in such a situation, bangs on full opposite rudder. On a Jungmann this is a thousand percent more than is required, and the usual result is an instantaneous (and often catastrophic) swing in the opposite direction. The engineering officer at Albacete devised two small links which are fitted to the undercarriage support struts and have the effect of altering the geometry so that it compares with the Jungmeister: and this apparently completely cures the swing problem. The Jungmann has one advantage as a trainer, and this is that it prepares a pilot for conversion to a Messerschmitt 109. which I am told on good authority by the Confederate Air Force has an even greater tendency to take its pilot for a ride on landing. This feature, however, is of dubious advantage unless one owns a Me-109.
As well as being affected by oleo compression, the toe-in of the Jungmann undercarriage is further modified by the angle to which the tail is raised, and the behaviour is also altered by the tyre pressure, with the result that it is unlikely that any two take-offs or landings will be the same. This tends to keep Jungmann pilots on their toes (literally) during the take-off and landing phase.
The tailwheel steering is very direct and powerful, and only tiny rudder inputs are needed to steer. The toe brakes are cable-operated, and even if the brake on the rearward moving pedal is held on, the geometry is such that the brake is released at the wheel, so that brake is only available to assist the turn in the direction of applied rudder.
In the initial stages of take-off aileron is of prime importance. If the turn on to the runway has been sharp, the aeroplane can list very slightly on its soft oleos, and it is a good idea to get the wings level as soon as possible to preclude any swing. Coarse aileron is used early in the take-off run to achieve this, and if there is any crosswind, aileron is held into wind with the idea of lowering the into-wind wing. Very little rudder is then required to keep straight, and the aeroplane is flown off with the tail held low. If the stick is pushed too far forward the undercarriage oleos suddenly compress as the weight is transferred forwards. As well as giving the pilot a bit of a fright, this alters the toe-in geometry and makes the aeroplane more sensitive directionally. With the tyres partially deflated, the aircraft is much more controllable on the ground; whilst on grass all its little tricks disappear.