Q) Is RB396 being restored to static display or airworthy standard?
A) Airworthy. The project and charity is based around returning RB396 to flight for display to the public.
Q) What engine will we be using for RB396?
A) Napier Sabre. The Typhoon was only ever powered by the Napier Sabre IIA. The engine is so synonymous with the Typhoon it is very hard to think that one could even call the aircraft a ‘Typhoon’ without it.
Q) Will RB396 be a car door or sliding hood Typhoon?
A) RB396 was a late model MkIb, meaning she had a sliding (bubble) hood canopy and the larger tailplane. She will be rebuilt to this specification.
Q) I heard the engine was unreliable and prone to failure, how will you overcome this?
A) The Sabre was developed during a time of total war, the Typhoon itself was rushed into service before it was truly ready for action. Luckily these problems were ironed out, in particular the work done by the Bristol Engine Company. By the last years of the war they were highly reliable.
Safety is our prime concern, and our engines will be maintained to the highest standards but also include modern materials, lubricants, fuels and technologies to mitigate risk.
Q) When will RB396 be ready to fly?
A) We have set ourselves a target of getting the aircraft flying in time for the 80th anniversary of D-Day (June 2024) which we consider a fitting date for the aircraft to make its debut.
Q) Where is the project based, can I visit RB396?
A) RB396 is currently in store in several locations and currently cannot be viewed. We are working hard to secure a permanent home for RB396 as we begin the long rebuild process. We plan to have the site open for visitors in the future with a Heritage Centre where you can have the complete Typhoon experience.
Q) How will RB396 be rebuilt?
A) A mixture of the original drawings and recovered parts will provide the data required to rebuild RB396. This work will be carried out by professional CAA approved restoration shops with the team overseeing progress. Items that do not require CAA sign off will be restored by volunteers and staff, making this a true team effort. As the project progresses so will the need for help from our supporters so stay tuned – you do not have to be an engineer to assist the rebuild, there are plenty of essential tasks to be completed.
Q) Who will own the aircraft?
A) The team has set up a charity (Hawker Typhoon Preservation Group) to own, restore and operate the aircraft. This is very important because under UK Law, RB396 forms the nucleus of the charity, therefore it cannot ever be sold into private hands and cannot leave the UK. This means any donations made to the charity go directly into the benefit of the aircraft and the Heritage Centre. As trustees of the charity we cannot make profit or sell any part of the charity for personal gain, we felt this was the honest way of restoring the aircraft where it will always be accessible by the public.
Q) How much will it cost and how will the aircraft be funded?
A) The full rebuild and establishing of the Heritage Centre will cost between £4-6 million.
The trustees have already invested substantial amounts of their own time and money just to get the project started, however, the rebuild will be financed entirely by public donations and support. As mentioned above, we are established as a registered charity (no. 1167143) and as such you can be sure that every penny you donate will go towards the furthering of the charity’s aims (see below).
Q) What is the Hawker Typhoon Preservation Group, and what are its goals?
A) The Hawker Typhoon Preservation Group is a charity set up by the Trustees (Dave, Sam and Jonathan) whose job it is to ensure its goal to rebuild RB396 to airworthy condition and establish a Heritage Centre for the Typhoon is met. We have launched a Supporters’ Club which will allow you to be a part of this exciting project, we will constantly be reviewing and expanding our merchandise range and attending air shows in the coming seasons. You can already make a donation direct to the project.
Q) The Typhoon was unsafe, the tails broke away and the engine was un-reliable, how can you operate the aircraft safely?
A) As mentioned, safety is our prime concern and no stone will be left un-turned to ensure the aircraft is built properly and in accordance with regulation. The first step towards this is assigning the rebuild to a professional restoration shop. During the war the Typhoon encountered many problems due to the fact it was rushed into service. The most infamous of these included structural failure of the tail assembly. Due to the fact the Typhoon was so desperately needed on the front line, there was a furious effort to solve these issues, this lead to the Typhoon being one of the most tested aircraft of the war!
By 1944 these early issues had been solved and the Typhoon enjoyed reliable operation for the duration of its service, see ‘About the Typhoon‘ for more history.
Q) Was the Typhoons reputation of being unreliable justified?
A) The Typhoon has suffered with many misconceptions over the last 70 years. In its early service days this was primarily due to the fact the type was tested and proven in service conditions unlike the earlier Hurricanes and Spitfires. The engine was a completely new design and the subsequent stresses on the airframe were unknown. The reliability of the engine was increased overnight when Bristol agreed to help Napier with the sleeve valves, the ground crews were eventually prevented from adjusting the throttles to over stress the engine and in field servicing vastly improved with experience. We do of course today have the ability to pre-oil engines and monitor the condition in detail while in service.
As for the tails, it is a common misconception that the sole responsibility of the tail off phenomenon was the failure of the elevator mass-balance alone. This was certainly the end result following a series of issues. The failure of the mass-balance was the final stage as once this happened there was an almost immediate loss of tail as the weakest point failed. Examination of the wreckage from all the failures and in particular discussions with F/O Will “Killy” Kilpatrick, the first pilot to survive a loss of tail when flying MN510, led initially to the complete redesign of the mass balance weight and the solution was put in place in October 1943. A combination of a 16lb control column interia weight and an 8lb elevator mass-balance weight, retaining the re-inforced mounting bracket, changing the geared balance tab to an ordinary adjustable trimming tab and removing the damping cords on the trailing edge of the rudder (needle bearings had been introduced throughout the elevator control circuit) was the final solution in the redesign of the system. From early MN series these were introduced in production and according to Service Department records no Typhoon incorporating the modifications ever suffered tail breakage.
Rolling back to the initial ‘tail question’ though, the cause of the fatigue failure of the mass balance brackets was confirmed in September 1943 when F/S Waddington (183 Squadron) returned from a dive-bombing trip over Poulmic Airfield. He reported experiencing elevator flutter as he began to pull out of a dive at 535mph. The disturbance had been sufficient to elongate the elevator control rod holes which in turn had caused flutter in the elevators. In extreme circumstance the flutter was immediately felt by the pilot however, in this case the flutter F/S Waddington felt was not enough for him to be concerned about the tail, it could almost be attributed to normal flight conditions, but this was actually causing fatigue on the balance weights through elongating the holes for the control cables. We all know the end result…
When in early 1944 the entire tail plane design was replaced with the Tempest then the accident rates attributed to this issue were not seen again. Some people point out that tail failure still occurred into 1945 and while this is true in a few cases it was down to completely different reasons that were attributed to combat conditions. Tail failure occurred after undercarriage doors and/or legs dropped in flight initiating the events for a tail failure.
Q) Is RB’s Sabre complete?
A) Until completely stripped nothing is a sure thing however, 2484 has been weighed and this suggests that internally it is complete. In addition to this we have closely inspected the engine and all the steel lock wire is in place (which appears to be factory applied) in addition to the factory fitted exhaust port covers which supports the news that 2484 was an ‘Unused Sabre’.
Q) What colour was RB’s Sabre engine?
A) 2484 has received at least 2 coats of ‘battleship’ grey paint since leaving the Napier factory. Although this isn’t standard it has helped to protect the engine over the last 70 years. Areas of paint that are peeling confirm that the engine was originally black and so it will be returned to this colour when rebuilt.
Q) Are any items missing from the engine?
A) There are a few small items that are missing from 2484, items that would not be needed in a training or display environment. These items include the exhausts, Coffman starter, starter motor, air compressor and a generator. We have a large number of original exhausts already, the Coffman starter cannot be used so will have to be replaced with an electric conversion, a supporter has an original Air Compressor and we have a lead on some spare generators.
Q) Do we have any spares for the engine?
A) We have a large number of items from the engine that arrived from Belgium for the launch plus a number of crates of spares also from Belgium. In total there is an additional 1/2 an engine which we believe will be enough to ensure we can get 2484 running.