A Napier Sabre engine IIa was centre stage during a talk organised by the Uckfield-based Hawker Typhoon Preservation Group last week.
Knowledgeable and enthusiastic members of the group travelled from as far a field as Worcester and asked questions of an expert about the engine which, following renovation, is destined to take Warbird RB396 back into the sky, hopefully in 2024.
The engine has always been on display during talks about the restoration of the Hawker Typhoon, and on open days, but this was the first time people were able to learn about its innards.
The person with the expertise was Clen Tomlinson, a model engineer and chief Engineer for the Napier Power Heritage Trust for many years. He had made small working replica engines in the past, but wanted to make a working replica of a complex engine.
Clem told Uckfield News: “If you want anything complex then D Napier and Sons is the company to consider. I looked at some Formula One engines, car engines and aeroplane engines.
“Nobody had done a Sabre engine so I set about trying to get information on what goes on inside there.
“I didn’t get on very well. I couldn’t find any drawings therefore I chose another Napier engine, a complex alternative engine, not a steam engine, a diesel engine.”
Clen completed an eighth scale replica of that engine then found a way into getting drawings for the Sabre and started the long process of converting what is inside that engine into a number of parts that could be assembled.
The result was a quarter scale model and a vast knowledge of the Sabre’s workings that Clen was able to share with the Hawker Typhoon group members.
Video clips within Clen’s talk illustrated how the parts worked together.
The Sabre IIa is an H24 configuration with two flat 12-cylinder, four-stroke, engines, one mounted on top of the other with the crankshafts geared together. It’s a ‘hyper’ engine.
Clen said that during the Battle of Britain the old way of defending the country was to send up a squadron of aeroplanes to look out for the enemy. The problem was they would run out of fuel.
The new Sabre ‘hyper’ engine allowed aeroplanes to sit on the ground – radar was coming into use at the same time – and be sent up as enemy aircraft approached and have a longer duration in the air and be very fast.
When the Hawker Typhoon Preservation Group’s RB396 returns to flight it will be the first time in 70 years that a Napier Sabre engine will have been heard.
But Clen told group supporters that a couple of CDs exist where the sound of a Sabre engine starting up, taxiing, taking off and flying past has been recorded, and it was a sound that was very nice to listen to.
Keep up to date with progress on returning Hawker Typhoon RB396 to flight on the preservation group’s website: https://hawkertyphoon.com
Read more about the Hawker Typhoon restoration in previous Uckfield News stories: