PERCY JACKSON (1897-1984)
THE LIFE &TIMES OF PERCY JACKSON
Percy Jackson a native of Selby Bridge in Yorkshire was educated at Halifax Grammar School and the Municipal Technical College. On leaving school he began working for Civil Service Examinations, but these were cancelled on the outbreak of the 1914-1918 war. In 1915 he started an apprenticeship with the Campbell Gas and Oil Engine Company in Halifax starting at 6am on a Monday morning in brand new overalls. His first job was to clean a new Gisholt turret lathe, which had just been delivered from America . A 6in belt drove the lathe. The piecework time for turning, boring, screwing and cutting the bands was twenty-seven minutes. Later as war in Europe intensified, this work was taken over by local civilian staff. Percy was then moved to the engine erecting shop. It was hard work, from 6am to 6pm and then studying at night classes, with very strict discipline.
In those days the primary products of the Campbell Company were horizontal four-stroke cycle single and twin cylinder engines, with a compression pressure of about 280lb/in2. They employed a blow lamp for heating a hot bulb before starting and during light-load running, with water injection to prevent pre-ignition at full load. The company also made vertical two-stroke crankcase-compression engines of up to four cylinders for driving electric generators, and also as a reversible marine engine. This engine also employed a blow lamp for heating the bulb before starting and during light-load running. While there were standard ranges of both these engines, the company was prepared to design a new size engine for any particular order, and they undertook many waterworks and sewage works pumping jobs with engines driving horizontal three-ram pumps. Horizontal and vertical gas engines were also built up to about 400hp and, as usual in those days, all components were made in the works, including lubricators, piston rings, fuel pumps, injectors and ‘make and break' for low-tension spark ignition. The company also made gas plants for generating producer gas from such waste material as wood refuse and coconut husks, as well as from coke.
All this was very varied experience, but on looking back it seems amazing how a small drawing office of around twelve draughtsman, many of them juniors, were able to produce such a wide variety of drawings. Drawings in those days did not contain the detail and information of the present-day drawings, but a senior draughtsman was not worth his salt if he could not turn out a full sheet of details per day. They did a job which nowadays we should find hard going. There were no such positions as Technical Manager or Technical Director and very few Chief Engineers in those days; the Chief Draughtsman was in charge of the design. Similarly there were no Financial Directors, Controllers, or Chief Accountants; the book keeping-cashier sat at a high desk on a high wooden stool with the petty cash at his elbow. The managing director or owner decided the financial policy and also the product and production policies. It was a great calamity when the Campbell Company failed, due to a strike over which neither side would yield.
The secret of the engines of those days lay in the fuel pumps and fuel injectors. Every firm made its own design, and having covered them by patents, maintaining the greatest secrecy over the details of design and construction. Compression pressures were much too low for satisfactory light-load running. It was a matter of sensitive judgement on the part of the operator to determine when to take the blow lamp off as load was increased, and when to apply it when load was taken off; also when to use water injection to control ignition. Brake mean effective pressures were about 65lb/in2 and revolutions about 220rpm per minute for a 100bhp engine. The two-stroke cycle crankcase-compression engines ran somewhat faster at about 350 rev/min for stationary work but were reduced to between 250 and 300 rev for marine work. During the 1914-18 war, Campbell's did make a vertical version of their horizontal four-stroke engine, but it had horizontal valves and a combustion space similar to that of their horizontal engine. The camshaft was situated half-way up the engine with the valves operated by a vertical pushrod to the inlet valve and a diagonal pushrod to the exhaust valve, as employed a decade later by Blackstone .
Campbell's also made an experimental stepped-piston engine, a type made at that time by J Samuel White at Cowes for submarine work. This type of engine, although very simple has gone out of favour, because any blow-by of sparks past the power piston caused explosions in the air above the stepped piston. Also there was the problem of supplying a relatively large receiver volume to avoid compressing the air supply to too high a pressure in the stepped piston space.
1914-1918 WAR SERVICE
Percy Jackson's period in the drawing office of Campbell's was relatively short since along with others he joined the Royal Naval Air Service in late 1917 and was drafted to the dirigible Airship Station at Pulham St. Mary, Norfolk . After a few weeks' training he was drafted to Biggin Hill aerodrome in Kent for a course of instruction on oil engines. Included in the draft was the late Mr. George Hallewell, who ultimately became Technical Director of Blackstone's of Stamford. The power station at Biggin Hill contained two horizontal twin-cylinder Fielding & Pratt engines of similar type to those made by Campbell's, again with low pressure and a blow lamp for heating before starting. The engine ran at about 200rpm and drove Brush dynamos by belt from the flywheel. It was a rule at this power station that the two engines had to be run alternately. One day, however, the day shift, under instruction, had taken a piston out of the standby engine then put it back; but when the shift ended for the day the connecting rod bolts had not been inserted for the coupling up. The night-shift came on duty and started up this engine, blowing the piston out of the cylinder until it was jammed against the crankshaft. This caused a court of enquiry, with three or four brass hats from the War Office.
Percy Jackson travelled over 12,000 miles in Scotland during the 1914-1918 war, attending to engines of various types. These ranged from small Gardner gas engines to Ruston, Crossley, Campbell, and other horizontal four-stroke cycle oil engines, with Keighley, Campbell and Petter crankcase-compression two-stroke engines thrown in, all having the weakness of low compression, poor starting, erratic slow running, and knocking under heavy load. To prevent this last drawback water injection was commonly used.
In view of these early experiences with detonation and the necessity for water injection on early oil and gas engines, and having seen the semi-diesel engine develop to its present stage of compression air-injection diesel engine progress into the airless-injection engine that is now universal. He felt qualified to express an opinion on the relative influence of the inventions and work of Diesel and Akroyd Stuart. It was his opinion that Diesel invented compression ignition. While Akroyd was the first man to employ airless injection with a pump and atomizer, he did not persist with this idea, which was later developed by Campbell, Crossley, Ruston and others, all of whom made their own pumps and injectors. It was not until the so-called semi-diesel engine increased its compression pressure cautiously from 280 through to 460 psi, between 1914 and 1925, that we eventually got the high-compression cold-starting airless-injection engine. This has enabled the basic type to run at higher speeds, use heavier fuels, and become the economical simple and efficient oil engine of today. Equally, the air-injection so-called diesel engine has become more efficient and reliable by eliminating the high-pressure air compressor and adopting airless injection of the fuel. The two systems have thus been almost imperceptibly merged; but the diesel cycle employing compression ignition did, he believed, lay the foundations of the present day compression-ignition engine, even if the actual contributions of Diesel and Akroyd Stuart were less than those of the firms who made their basic engines into practical and commercial propositions.
FRASER AND CHAMBERS
On demobilisation after the 1914-1918 war Percy Jackson returned for a short while to the drawing office of Campbell Gas Engine Company, then onto the English Electric Company, engaged in designing and detailing of their first Fullagar opposed-piston engine. In 1922 this experience was to serve him well when joining Fraser & Chalmers on the development of their advanced highly rated diesel engine. All the hot combustion chamber parts ie cylinder head, piston top, and cylinder liner were relatively thin and were supported by strong, well cooled members, the cooling water being circulated at high speed between these parts. This is also the principle behind the thin, reinforced cylinder liner construction of the Doxford engine, but the development at Fraser & Charmers and that by Mr. K. O. Keller at Doxford's were entirely independent of each other. Fraser & Chalmers gradually dropped out of the diesel engine manufacture, which was unfortunate because the design was advanced and a good engine.
Also while at Fraser & Chalmers he met a Mr. G. R. Hutchinson Technical Editor of The Marine Engineer. They use to attend meetings of the Institute of Marine Engineers, and at one of these meetings a paper was read by Dr. F. Sass a designer of the AEG large marine oil engine. The paper received considerable criticism, particularly from Mr K.O. Keller, who contrasted the German engine with the Doxford and was ultimately pulled up by the chairman of the meeting, much to the annoyance of Mr. Keller for so-called advertising of his engine.
In his early days as a draughtsman Percy Jacksonhad a strong desire to get into bridge design., He applied to Fox & Partners for a position when they were designing the Sydney Harbour Bridge . He was offered the post, but it was explained to him that the rent and rates of the drawing board which he would occupy in Bush House would be some £4 per week; and while they were prepared to offer him a higher pay than he was receiving, this, together with the £4 rent, would require about twice the normal output of a draughtsman working in the provinces. He had no experience of bridge design, and he had been married for only three years, with one child, he considered the risks too great. This was to be the only position he ever turned down. Whether he would have done well on bridge design will remain unknown.
In 1937 Percy Jackson joined Mirrlees, Bickerton & Day to see the last of the firm's air-injection engines on test. Mirrlees had stuck to the air-injection engine for too long and it had become non-competive in price relative to the airless injection engines being made by the so-called semi-diesel companies who had adopted the higher compressions and CAV-type injection pumps and injectors.
It is not generally known that in 1943 Percy Jackson developed a two-stroke cycle valve-in-head uniflow-scavenging engine at Mirrless which had a Roots scavenging blower driven from the camshaft gearing. To his great regret, its development was not completed after Mr. A. Good acquired control of the Mirrless works. When the engine was ready to start, in October of 1943, at twenty minutes before noon, the foreman in charge of the test came to tell him that it was ready but that he was proposing to delay its start until after lunch. The works lunch was 12 till 1-00pm the office was 1-00 till 2-00 pm. When Percy Jackson returned from lunch at 2-00pm the foreman was waiting with a long face. The engine was in two pieces. Subsequent investigation showed that the rubber rings at the lower end of the cylinder liners had fouled the cylinder casting when it had been inserted and had been cut and thus not making a water tight joint. The water had been left on the engine during the work's lunch break and had leaked past these water rings into the scavenging air space below. On the first start the engine ran up to speed and the air from the blower had blown the water into the end cylinder, which had caused the fracture with the crankcase in two pieces. He had the task of telling Mr. Day of the mishap. It was a great pity that this engine was not pursued, since it had the merits of the modern valve-in-head two-stroke, and could easily, according to later practice, have had a turbocharger instead of the original Roots blower.
In 1947 Percy Jackson joined William Doxford & Sons.