Bristol 171 Sycamore

With each new Flying Bulls aircraft, the search for another, as yet unused superlative becomes a little more difficult. For once this proved quite different for the youngest member of the Flying Bulls. The term was immediately clear: unique. And not as a drinking yoghurt might claim for itself, but in its most original sense: unique. The Sycamore in Hangar 8 is the only surviving flying specimen of this type in the world!

The Sycamore is named after the sycamore maple. Why? Anyone who knows the spinning movement of a maple seed falling from the tree knows why. The rotor blades are made of Australian maple wood – which initially raised major concerns with Blacky Schwarz, the Flying Bulls’ chief helicopter pilot. But we will get to that.

At the end of World War II, the Bristol Aeroplane Company in the UK started developing a new type of helicopter. The first helicopter built in the UK was constructed under the direction of the Austrian Raoul Hafner, who emigrated to the UK before the Second World War. The prototype flew its maiden flight in 1947. In 1949, the second version, the Mk 2, was followed by five seats and equipped with a 550hp English Alvis Leonides 9-cylinder radial engine. The horizontally installed engine behind the rear seat is undoubtedly an unusual sight today. In its time, however, it was completely normal because row motors could not yet be sufficiently cooled. The Sycamore was equipped with a three-blade head rotor and a three-blade tail rotor, together ensuring reduced vibration and improved efficiency. They are, however, a significantly more complex design than two-bladed rotors. The rotor blades, made entirely of wood, are delicate craftsmanship masterpieces. The main rotor has been designed such that the blades can be folded aside, i.e. towards the tail fin. This saves valuable space on naval ships and in the hangar.

Hafner’s construction became a major commercial success. The Bristol 171 was far ahead of its time with its high-strength hull cell made of hydronalium (a saltwater-resistant aluminium alloy), a top speed of almost 200km/h and a range of around 430km. Air and naval forces in many countries were equipped with helicopters, followed later by orders for sea rescue and passenger transport craft.

The Flying Bulls’ example was built in 1957, serving as a military helicopter in the German Armed Forces. It retired in 1969. After several detours the machine eventually reached Switzerland and collector and helicopter enthusiast Peter Schmidt. It was a winery owner who also put a lot of love into it. He even obtained a special permit from Queen Elizabeth II herself, so that the Sycamore could carry the colours of her origin, the Royal Air Force (RAF), as well as the British emblems. Permission was granted on the strict condition that this Sycamore should exclusively honour the RAF. Small wonder, as in British traditional aviation circles the machine is almost considered a national treasure.

The former owner’s most ardent wish for his Sycamore was to keep her airworthy. Only very few lovers worldwide could be considered for this. The trusting handover to the Flying Bulls took place, including a huge stock of spare parts which the previous owner had meticulously collected over the years.

For Blacky Schwarz feelings of joy were mixed with respect for the unique piece. Are the wooden rotor blades still safe and reliable? Elaborate tests were conducted by the TU Graz. The result surprised everyone. “Like new”! All that remained was to learn its flight characteristics. Unfortunately, there is no longer a flight-ready pilot with a valid licence for the Sycamore. The Bristol now presents one of Europe’s most experienced helicopter pilots with a task he probably would never have dreamed of: before the major overhaul, Blacky Schwarz will have to teach himself the idiosyncrasies of the Sycamore. The team should have it in them though. The helicopter, with a rotor diameter of 14.8m, is considered hard to fly. But who should succeed in this feat, if not the world champion in freestyle helicopter flight?

She is the last flying Sycamore in the world!

Bristol 171 Sycamore