MK356 is a Mk IX Spitfire built at Supermarine’s Castle Bromwich factory in early 1944. She was fitted with a supercharged Rolls-Royce Merlin 66 engine optimised for low altitude flying, making her an ‘L.F.’ (Low Flying) Mk IXe variant.

During the latter stages of World War Two on 4th February 1944 MK356 was delivered to the Royal Air Force, being allocated to 443 ‘Hornet’ Squadron Royal Canadian Air Force, part of 144 Wing at RAF Digby led by Wing Commander ‘Johnny’ Johnson, the RAF’s highest scoring fighter ace.

MK356 flew sixty missions with 443 Sqn between 14th April and 14th June 1944, taking part in D-Day operations, during which Flying Officer Gordon Ockenden RCAF shot down a German Messerschmitt 109 on 7th June, D-Day+1.

On the culmination of her sixtieth sortie on 14th June 1944 MK356 undertook a ‘belly landing’ with undercarriage retracted, spending the next 53 years grounded before being returned to airworthy condition and joining the RAF’s Battle of Britain Memorial Flight at RAF Coningsby in 1997, in whose care she remains today.

MK356 is a rare, genuine, D-Day veteran.

Pieces of History

As with all old machines, a degree of mechanical replacement is necessary to maintain operational condition. A few years ago, MK356 had her original Duralumin main spar removed.

The main spar is the load bearing backbone of the aircraft, running along the wing and connecting it to the fuselage. The spar consists of concentric tubes providing strength with flexibility, essential to absorb and tolerate high g-forces incurred during aerial combat whilst avoiding fracture. At the root there are five tubes (with central plug), diminishing to just half a tube at the wing tip, where the required strength reduces.

TMB acquired the redundant spar directly from the BBMF and it is of this original, genuine, ex-D-Day Spitfire provenance metal that our collaborative Onoto – TMB MK356 pens are crafted.

Melting Down

Firstly, the Duralumin spar is melted down at a London jewellery caster.


Once molten, the metal is poured into a lost wax casting ‘can’ to form rods, which will later be machined.


In the second physical process, these same cast rods are machined into their final form. Ultra-modern computer-operated lathes ensure absolute perfection and precision in both tolerance and craftsmanship.

The Spitfire Pen MK356

To mark the 80th anniversary of the Normandy D-Day landings, Onoto and TMB Art Metal are proud to bring you the Spitfire MK356 pen. A limited-edition tribute to the Royal Air Force’s iconic Spitfire, crafted from Duralumin originating from D-Day veteran MK356. This pen captures not only the Spitfire’s iconic aerial form but its celestial spirit.

The Spitfire MK356 Pen is available in a limited edition of 100 pens.