Frank Perkins is widely known as the man behind the Perkins Engines Company of Peterborough, now a fully owned subsidiary of Caterpillar Inc., which bought the business 23 years ago for $1.3 billion

Its beginnings were a little more modest though and date back to the early thirties, when Frank Perkins and a rather unassuming but brilliant engineer, by the name of Charles Chapman, started to sketch out the design of a lightweight diesel at Chapman’s home in Strood, Kent.

The two were convinced that a new lightweight compression ignition (CI) engine would hold tremendous appeal in many situations where reliance was then being placed on the petrol engine, including tractors.

Massey ferguson 35 with high speed oil engine
The highly popular ‘Massey 35’ used a three cylinder Perkins engine

According to Chapman it was a very basic start, about as far removed from today’s engine modelling programmes and CAD as is possible, as the two drew up plans for the new engine on various scraps of paper that Chapman had on hand.

Later he was to recall that first design process:

“As we sat there and made suggestions, using the arm of my chair as a desk, I made rough thumbnail sketches, illustrating them, on the back of one of my envelopes, and so, gradually, the system took shape”

Initial concept

The first task was to establish the parameters of a new type of diesel engine which would be crucial to its success as a competitor to the far less efficient petrol engine.

The criteria included a small size with a similar power output to petrol engines, and, just as importantly, it had to reach similar engine speeds to ensure that it would match the transmissions already installed in vehicles.

It was this latter requirement which caused the most head scratching, for a drop of atomised diesel had to be introduced into the cylinder, ignited and burnt, all within a thousandth of a second if it were to run at a similar pace to petrol engines.

This was, at the time, considered impossible; but Chapman cracked the problem with the use of a pre-combustion chamber and a pintaux type injector.

The pintaux is a development of the pintle injector, it has an extra hole bored in the side of the nozzle body. This smaller hole directs a tiny quantity of fuel into air that is being forced into the pre-combustion chamber by the rising piston.

By doing so it causes it to ignite and form a flame front, which then travels through the main fuel load that awaits it in the pre-combustion chamber. This arrangement was named the Perkins Aeroflow system and it stayed in use until the late seventies.

The ‘oil engine’ comes of age

And so was born the modern high speed oil engine, a term that Chapman later used as a title for a book which went on to become the standard text for apprentices and mechanical engineering students everywhere.

High speed oilengines fitted to Massey Ferguson tractors
Massey Ferguson were so impressed by the product they bought the company in 1959. Commer was also an early customer

Among engineering circles he is often thought of as the father of today’s diesel engine.

He took the heavy, slow running combustion ignition engines that thumped reliably away in ships, power stations and the occasional vehicle, and brought to them a refinement.

This made them suitable for a far wider range of applications, including tractors.

Despite this, he is rarely mentioned in the annuls of engineering history in the same breathless tone as Rudolf Diesel himself, and it must be remembered that Herr Diesel was not the first to build a working CI engine – that honour falls to the Hornsby Ackroyd motor patented three years earlier, in 1890.

Chapman’s Roots

Charles was born in Lancaster in 1897. He attended the Lancaster Royal Grammar School (which fails to list him on its Wikipedia page) before being apprenticed to Vickers Ltd. in Barrow in Furness.

During WW1 he served in the Royal Navy Volunteer Reserve working on anti submarine measures, before returning to civvy street and studying for an M.Sc in engineering at Liverpool University.

From there he joined Petters (Ipswich) Ltd. who were building large diesel/oil engines for his old company Vickers. Although Petters eventually went on to become Westland Aircraft, the Ipswich facility closed in 1929, leaving Charles looking for a job.

He found one at Aveling and Porter of Rochester as a personal assistant to the works’ work director, a fellow by the name of Frank Perkins.

During the next couple of years, he also became secretary to the board, a job which mainly entailed fighting off creditors for the financial situation of the company was dire – in early 1932 it eventually succumbed to the great depression.

Starting afresh with Perkins Engines

This collapse left Charles and Frank looking for gainful employment, of which there was very little at the time.

However, one of the development projects of the bankrupt company had been a small diesel engine that would rev up to 1,200rpm, but no more, despite its compact dimensions.

This was known as the Invicta engine and both men felt that it had held great promise as a lightweight power source for smaller applications.

In April of 1932, Frank Perkins wrote out his prospectus to form Perkins Ltd. of Peterborough, the home town of his family’s engineering business.

Barford and Perkins family
Barford and Perkins was the family engineering firm based in Peterborough

Francis Arthur Perkins was the elder of the two, was much more flamboyant and had the family connections which were able to invest in the new company. He had served in the Royal Engineers during the war where he risen to the rank of major.

It was perhaps inevitable that the new company took his name, especially as he was to be chairman with some of his own cash invested in the venture. Chapman filled the position of technical director and all patents were to be registered in the name of the company rather than the individuals.

Within six months the first prototype was ready and on December 3, 1932, it was fired up with all the company personnel present.

Having raced up to an unprecedented 3,000rpm it had to be quickly shut down again as the dynamometer was about to overheat through lack of coolant.

What makes this event remarkable was that there had been no single cylinder model to test the concept first, as Chapman had wanted. Perkins had insisted that the design go straight from the back of an envelope to a running example in a bid to save time and cost.

This was the birth of the Perkins legend, yet it took another decade for the company to actually find itself on a firm financial footing. Reaching that point was, to a great extent, the result of Chapman’s continued hard work and the vagaries of the Second World War, especially the need of the Royal Navy for a reliable diesel engine for its smaller craft.

Stepping back

In 1942, Chapman retired from the company’s board to concentrate on helping the war effort. In 1951 the firm went public and Chapman realised just £16,100 (around £475,000 today) from his original holding of 1,000 shares.

The Perkins family however, received £387,000, or approximately £11.4 million adjusted for inflation.

Perkins engines in tractors
Lindner of Austria is still a keen user of Perkins engines

It would be easy to dismiss this as grossly unfair to the man who had worked without break to create an engine that changed the worlds perception of the ‘oil engine’ from a efficient, but clumsy power unit, to a sleek and powerful engine that now performs even beyond his own wildest imagination.

However, it is highly unlikely it would have brought it to market without the drive and ‘Brutal business-like brain‘ of Frank Perkins. Frank was the dynamo that pushed at the envelope and it is he who is celebrated as the father of the high speed oil engine.

Yet, scratch away at the surface and it becomes clear that it would never have happened without Charles Wallace Chapman, the forgotten engineer by whom we have all benefited.