John Cobb's Three Successful Land Speed Record Attempts

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An Interview with Jim Rands

[The late John Cobb three times broke the World’s Land Speed Record in his twin-Napier-engined four-wheel-drive Railton Special, the last piston-engined car to hold the ” fastest-ever ” title, at 394.196 m.p.h. That speed was recorded at Utah in 1947. It was beaten by nine m.p.h. in 1964 by Donald Campbell, O.B.E., whose Bristol-Siddeley Bluebird gas-turbine car was nearly twice as powerful and cost at least fifty times, perhaps 150 times, as much as Cobb’s car. In one direction Cobb was officially timed at a speed fractionally greater than the 403.1 m.p.h. to which Campbell raised the record 17 years later. In an interview with JIM RANDS, who, as a member of the Thomson & Taylor team, accompanied Cobb on all these record attempts, I learned at first hand some fresh aspects about how comparatively easily Cobb attained his goal, and some interesting new aspects of these fascinating runs by the last successful reciprocating-engine L.S.R. car.—Ed.)

What follows are notes about John Cobb’s successful bids on the L.S.R. in the Reid Railton-designed car he used for this purpose in 1938 (350.20 m.p.h.), 1939 (369.74 m.p.h.) and 1947 (394.196 m.p.h.). I do not propose to describe the car itself, ingenious and effective as it undoubtedly was, because its, and all the other L.S.R. bids made between 1898 and 1964, are admirably covered, together with a description of each visit to the Utah Salt Flats, in that excellent little 15s. book ” The World’s Land Speed Record ” (Phoenix House, 1964). What I hope this article will emphasise, with Jim Rands’ patient explanations and his unique photographic coverage of Cobb’s activities, is how effectively Reid Railton, the late Ken Taylor, the late John Cobb and all those associated with these record bids accomplished what they set out to do—quickly, cleanly and without ballyhoo…. I think it may also present some hitherto little-known but very fascinating facts about these now-historic projects.

Rands recalls Wally Hassan, the liaison man, bringing the curious S-shaped backbone frame of the Railton Mobil Special into T. & T.’s Brooklands premises—it had been made by John Thompson Pressings—and the speculation which this odd structure caused among the T. & T. mechanics. It. needed two tables on which to set it up and mark it off, which was done unelaborately but effectively by well-tried methods.

Meanwhile, two ancient supercharged Napier Lion 1,250-h.p. aero-engines, dating back some eight years, had arrived, and special 3-speed gearboxes (with aluminium casings) from David Brown. It was apparent that Reid Railton, B.SC., A.M.I.A.E., was building a car in which John Cobb could have a go at George Eyston’s cumbersome and powerful 73-litre twin-Rolls-Royce-engined 8-wheeled Thunderbolt. Eyebrows must have been elevated when it became apparent that Railton intended to hang an engine each side of the frame, one at the from, the other at the back, and drive all four wheels of the car, with nothing but the throttle pedal to synchronise the speeds of the two power units. Excitement, too, was caused when the body was seen to be literally an all-enveloping shell, with no mechanism attached to it, and of near-perfect aerodynamic form.

Ken Taylor, with characteristic thoroughness, checked the clearances in the gearboxes and supervised the developing project. There was fun when it was decided to use Simmonds cables for coupling the distant gearboxes to the gearlever. A rep arrived, marked the run with an enormously long length of wire, found he couldn’t take this back by train to his office, cut it in half, and lost all semblance of what was required. A more technical bod took over, who possessed of a car, used stronger wire, and the cables were made. They took three days to fit, and a week before the mechanics made them function as required.

The body shell was made at Brooklands by George and Jack Grey. Very great care was taken to seal the bulkheads of the engine bays to ensure that fumes should not enter the cockpit, which, almost more revolutionary than the four-wheel-drive, was set in the very nose of the car, ahead of the front wheels. This 6-cwt. aluminium shell was located on the chassis by eight pegs and it is to the everlasting credit of the Greys that when it was carried from the shop was where it made and lowered onto the chassis for the first time, apart from easing one attachment, it fitted perfectly. The cockpit cover completely enclosed the driver, an open-top canopy having been made but never used. Cobb could release this lid by operating a couple of handles and the surrounds of the cockpit were of aircraft fabric, to enable the mechanics to break in, in ease of emergency—this, fortunately, was never necessary and the fabric was not disturbed. Cobb scorned a gas-mask but wore goggles in case any salt particles flew about the cockpit.

Transporting this smooth-surfaced 2.75/3-ton vehicle to Utah presented several problems. Malcolm Campbell’s Bluebird had been attached to its travelling crate by its wheelhubs and on the rail-road the movement of the truck as the train stopped and started broke a steering arm. So Railton was determined to anchor Cobb’s car more securely and into its big box prepared by Lepp Transport the unfortunate Rands had to crawl, offering up great steel plates to the wheels in the semi-dark and bolting them in place, after which he had to get a hand inside the car and free off the track-rod.

It took 20 men on each side to put the sides and top on the crate, which posed an unloading problem at the salt flats, where cranes were unknown until the U.S.A.F. moved in during the war. When lifted, the base of this crate bowed perceptibly under the car’s wheels, but all was well, and the precious cargo left for the Port of London: and by barge to the 27,000-ton motor-ship Georgie.

Incidentally, John Norris and Jim Rands became proficient in being winched up long ramps into the low-loader lorry which took the car from T. & T.’s to Lepp’s, but naturally, if Ken Taylor was present, his understandable anxiety gave rise to moments of alarm. In 1938 one spare engine was taken out to Utah, Dunlop, who made the special tyres with their 1/20 in treads sent Dunlop Mac, Harry Fletcher and Syd West, Readings, Rands and the very talented T. & T. chief draughtsman, Beauchamp, under Taylor and Railton, completing the team. No transport was taken, as Railton’s contacts produced Hudson cars on arrival. The record-car was started by pushing it and before leaving England the necessary attachment had been built up from drawings, for attachment to the front bumper of a Dodge truck on arrival at Utah.

The Railton Special had, in fact, never run in England, was never driven under power by anyone except Cobb, and he had never previously exceeded 170 m.p.h. (The engines could, of course, be started, for running up, on compressed air.)*

On reaching the salt flats the crate had to be levered sideways off its truck by gangers onto the Trans-Continental Highway and as someone always had to be in the cockpit to steer the car, after another cramped, groping, claustrophobic crawl into the box to release it. Rands had to worm his way into the driving seat before the Railton could be rolled out and towed off along the road. It was presented with an appropriate State Registration Plate this, but only as a joke, because when the body was lowered, it became invisible. In the same way, the boys of Cobb’s team went home with American driving licences, without taking the driving test.

RaiIton had arranged for the contracting drum brakes to be water-cooled and had put a vertical air-brake in the tail; the latter was tested on a workshop compressor in England but never used and was later removed.

The engines were cooled by a 75-gallon ice tank, Railton being able to calculate to within a few cubes how much ice would be needed for a given run. Shell-B.P. backed this attempt.

In 1938 rain made the course tricky, and, remember, Eyston was using it as well. The Railton gave only minor troubles, such as a tendency for one engine to run too hot. To cure this the dual thermostats controlling flow from the ice-tank had to be altered to separate the flow, and they were most inaccessible, as Rands recalls, the mechanics having to stand on their heads.

Cobb, who drove in a linen helmet, not a crash hat, had some startling experiences when the tyres, o/s. front, n/s. rear, lost rubber and three layers of canvas round part of their circumference. He described this as like a “terrier shaking a rat” but would continue full-bore over the measured mile. Apart from this, and denting of the body by downdraughts on the tail, Which had to be hammered out, the Railton gave little cause for anxiety, although Cobb’s very first run, with the body off, was almost as exciting as the record attempt itself, because, as the big engines thundered and the car accelerated away, the team knew the daring expedient of four-wheel-drive from separate uncoupled engines was going to work ! Cobb was soon doing test-runs in the region of 300 m.p.h.

Eyston had done 345.49 m.p.h. Cobb took the record, at 350.20 mph. That night both drivers and all Cobb’s team attended a dinner, during which Eyston told Cobb he wouldn’t have the record on the morrow and Cobb retorted “I hope it rains like hell!” Taking Rands aside to ask if the boys had any beer money—they were skint—Cobb doled out some dollar notes, remarking ” If anyone tells you a man can become rich out of the L.S.R., he is a liar!”

Cobb was the first driver to exceed 350 m.p.h. But shortly afterwards Eyston took his record, at 357.50 m.p.h. On Thunderbolt’s next attempt a crash was narrowly averted when part of the body became entangled with one of the back wheels, Cobb, his tyres nearly used up, had left for home.

During the winter of 1938/39 Railton instituted twisting tests on the frame, believing that the tyre trouble arose from torque distorting the backbone. The cure was to pre-load the two wheels involved, the suspension being set up in England, checked, and then set up again at Utah. To this end the back axle was now restricted to vertical movements only.

Cobb went out again on the eve of the war, Fiddle replacing Dunlop Mac., with Syd Cooper, otherwise the team was the same. Railton’s cure proved absolute, the tyres giving no more anxiety. It is typical of the careful attention to detail that the car was never moved on the wheels used for the runs.

” Slave” wheels were always substituted after every run and the special wheels removed to the van or depot. Even while fitting them, the special tyres were encased in a protective sleeve, to obviate damage from the surface, the sun, the body cowlings or the curiosity of onlookers. This, too, was a formidable task, each of the special rims carrying the 7.00 x 31 Dunlop thin-tread tyres being attached by 36 bolts. Incidentally. Schrader tyre valves were used. And the wheels were changed between every fast run.

Railton had contrived better breathing for the front engine, the salt was in very good condition, and Cobb beat Hitler, leaving the record at 369.74 m.p.h. just before war was declared. He had a difficult task, because there was no time to consult the minimum of instruments in front of him, although he glanced when possible at the tachometer for one engine. Above 300 m.p.h. he found the speed really something. Cobb was also hampered by the fact that if one engine fluffed out there was no means of restarting it, as free-wheels replaced clutches. The drill was that these were locked for the push-start, Cobb then kicked down the ” Clutch ” pedal which had a catch to hold it down, making the free-wheels operative for gear changing, then, after getting into top, he let the pedal up, so as to give engine braking on the over-run.

After the war, when a slight kink had to be incorporated in the measured distance to get firm salt, Cobb had to do the awkward, clutchless “round-the-corner” change into top at some 250 m.p.h. In 1939 records up to 10 miles were taken, as well as the L.S.R. The remarkable thing is that the old Napier engines had not been stripped down during the winter at home !

During the war the car—now known as the Railton Special, because it had last run under the auspices of the Gilmore Oil Co., not Mobil, although by 1947 this company was part of Mobil— was stripped, mainly to enable parts to be stored in dispersed places. In 1939 the ice-tank had been moved to the back of the chassis. Railton now extracted more power from the aged engines—”We used aviation spirit before the war, something more fancy afterwards,” recalls Rands. The ball and roller bearings had pressed in the gearbox casings and had to be chromium plated and ground to a fresh fit, new brake drums with a stiffened rib installed, and the car generally made ready. But it was unmodified, although the engines were to be run at 4,000 r.p.m. on increased boost—whereas Napier’s threw up their hands in horror at anything over 3,600 r.p.m. Testing was done on Thornycroft’s test bed at Caversham, the open exhausts thundering and banging across the river.

Previously there was no means of restarting a stalled engine during a run, which wasted time, so Railton evolved a simple but effective belt-drive from each prop-shaft, using twin fan belts over pulleys which, through the medium of additional free-wheels turned the engines if they happened to cut-out for any reason. As these belts would have been very tedious to replace had they broken, a spare set was taped around the shafting. But they withstood the load and never did break—Railton, once again, had calculated correctly.

For the post-war bid unloading was facilitated by an Air Force ramp at Utah, the crew being the same except that John Norris had taken Bob Reading’s place. Even in 1938/39 the local radio station had linked time-keepers and the turn-round points by short-wave radio (30 min, were allowed between the out and home runs), over which they broadcast a lurid account of Cobb’s progress along the course, useful to his helpers as well as a news-service to listeners. The mirage effect of the salt, by the way, made the car appear first of all up in the air, as it rushed towards Rands and his fellow mechanics waiting to change the wheels, replenish the tanks and turn the car around.

There was more trouble than before in 1947, mainly because the varnish had come away from the floats in the Claudel-Hobson carburetters, upsetting the mixture, elaborate flow tests giving no joy. Smaller jets, devised by filling them with solder and reaming out, cured that trouble. Then, on a run one morning, Cobb reported no power from one engine. A camshaft had seized in its bearings, locked the camshaft drive vertical shaft and sprung the driving bevel out of position. This was the first occasion when no spare engine had been taken out to Utah, but T. & T.s were ready at home and spares were flown out. A chunk of ice falling outside the tank during replenishment holed the tank, but after a stripping down session occupying from 2 a.m. on a Sunday to 2 a.m. on the Tuesday the mechanics knew what faced them…. The gremlins were beaten.

The Railton Mobil’s defective engine was re-assembled, Cobb went out, and with the car going from 0-400-0 m.p.h, in about 3.5 min., got the record up to 394.196 m.p.h., on bad, patchy-salt, giving him a difficult drive. Indeed the Railton had sunk well and truly into the salt on one run. In one direction a speed of 403.135 m.p.h. was officially timed; the car reached probably 415 m.p.h. momentarily.

The Railton, now in the Birmingham Science Museum, still holds the fastest-ever record by a piston-engined car and on this last occasion, the team was only away for about eight to 10 weeks; an achievement of which all concerned, with the calm uninterfering John Cobb to set the example, must still be very proud. W. B.