Challenger I

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The Challenger I is an automobile with which the American racing driver Mickey Thompson tried in vain from 1959 to 1962 to break the absolute land speed record . In the A / BFS class, it was able to set a record of 585 km / h that lasted for 31 years.

The result of enthusiasm

Challenger I from 1960 on with four compressors

Mickey Thompson has been building " Hot Rods " since he was ten years old and the Challenger I is likely to have been the eighth. The direct predecessor had two uprated Chrysler - engines was in 1958 on the Bonneville Flats km 473 / h fast and not too far from John Cobbs 1947er 634 km / h record removed. It took eighteen months of work to create the Challenger I , which confirmed Mickey Thompson's great organizational talent, as many of those involved in the construction of the car contributed their efforts free of charge. The most important thing in this regard was an engine donation from the GM Pontiac division , and on top of that, the sponsor group was led with a $ 1,000 check . Pontiac boss Semon E. Knudsen showed a personal enthusiasm for the project beyond business matters.

The " tuning " of the four 389 cubic inch V8 engines was carried out primarily by the incorporation of other crankshafts , which while retaining the bore of capacity each of 6374  cc to 6718 cc (partially of 7112 cc's speech) is increased and the compression to 13: 1 was increased. A loading effect (" air ramming ") was achieved through an air inlet opening at the top of the car, which at first glance looked like a cooling air opening. The engines were cooled by four water tanks behind the front wheels and in front of the rear wheels. Thompson wanted the vehicle to be as compact as possible. To do this, the four motors were placed in a rectangle on the workshop floor and the car outline was drawn with chalk. With the help of George Hill, the Challenger I took on its shape, Thompson's father carved a wooden “ mockup ”, California Metal Shaping roughly shaped the required sheet metal and Don Borth did the fine work on the construction of the aluminum body . That was kept very low as relatively small tires were made available by Goodyear , a company that also contributed to the funding and took care of the publicity work. All of this was improvised anyway: Thompson saw the route through a four-inch square sheet of glass that came from the face shield of a welder's helmet. A particular challenge for him and his mechanic Fritz Voight was the construction of the rather complicated clutch and shift connections , because the four LaSalle three-speed transmissions - built in 1937 - were to be operated with a single gear lever. If one of these transmissions did not shift into the next higher gear - the mishap was to occur later at an inopportune moment - the coupled engine would over-rev.

Sobering attempts in 1959

Thompson made his first really fast rides with the Challenger I during the "Bonneville Nationals" in August 1959, an event that got by without the expensive USAC timekeepers . The start took place by pushing to speed 120 km / h by an auxiliary vehicle. What initially caused problems was the braking process. While the Blue Bird CN 7 , which was about to be completed at the time, had modern disc brakes that should be used from 600 km / h downwards, Thompson resorted to drum brakes , which could only be used at much lower speeds. So Thompson let the Challenger roll out a few miles and then deployed a braking parachute . But that one danced in such a way that the car was pulled off the track. On the manufacturer's advice, the 15-meter line was cut in half, and Thompson now performed a looping trip with the released parachute with 400-meter deflections on both sides of the marked slope. The problems disappeared when the experts' tips were ignored and another braking parachute with a diameter of 1.80 meters was tied to a line extended to 23 meters.

Thompson delivered an event record for the " Bonneville Nationals " with 531.8 km / h and saved his reserves for the official record attempt in September. Although he drove really faster and set the record with 585 km / h in the A / BFS class on October 6th, he ultimately did not come close to Cobb's record. The fact that he broke the records of 5 kilometers (at 566.3 km / h), 5 miles (551.2 km / h), 10 kilometers (524 km / h) and 10 miles (454.9 km / h) at the flying start did not seem comforting km / h). In attendance at the time was George Eyston , an old competitor from Cobb's day, and opposite him Thompson abandoned his usual reluctance to give true horsepower figures. Eyston pulled a slide rule out of his pocket and after ten minutes said he didn't know exactly how much, but Thompson would need at least 300 to 400 horsepower more if he wanted to break the 400  mph .

A record and yet not

Thompson knew how to get the extra horsepower by installing four GMC 6-71 compressors in excess - there would be an additional 1,000 horsepower - but at the price of increased air resistance . Two air scoops on the bonnet and the covered front wheels characterized the 1960s version, and extensive modifications also resulted in changes to the body at the tip and rear. Mickey Thompson was able to meet the expectations placed on him with his car on September 9, 1960 and put in a run with 406.6 mph (654.35 km / h). The run in the opposite direction required to obtain the title failed, as it was said in the press, due to a gearbox damage.

Challenger I in front of the Blue Flame record car

Obviously, what could go wrong had gone wrong when shifting, a gearbox had got stuck and an engine was over-revved. Only, with an engine manufacturer as sponsor, Thomson could hardly announce that it had broken an engine. In 1962, Thompson stopped his efforts. In the years since 1959 he himself had experienced some critical situations on the Bonneville Flats, his competitor Donald Campbell survived a serious accident and Thompson's compatriot Athol Graham died in his car. Thompson announced that he would never again drive a car faster than 400 mph.

Technical specifications

General data

Wheelbase: 2770 mm
Front / rear track: 1330/1155 mm
Dimensions L × W × H: 6000 × 1520 × 990 mm
Car weight: 2540 kg

engine

Type: Pontiac 389 cubic inch V8 engine (enlarged to 6718 cm³) (4 pieces)
Working method: Four-stroke Otto
Power: 1600–2400 hp depending on fuel
Mixture preparation: mechanical Hilborn gasoline injection; Model from 1960 with four GMC 6-71 compressors
Fuel tank: 4 19 liter tanks in front of the front axle

Power transmission

Drive: all wheel drive
Transmission: 4 LaSalle three-speed gearbox; operated by a single lever

landing gear

Frame: Tubular steel frame with aluminum body
Brakes: two 1800 mm brake chutes on a 23 meter long line; Drum brakes for low speeds
Bikes: Magnesium wheels 21 inches
Tires: Goodyear 7.0 × 21 inches, 127 × 762 mm ( outside); Air pressure 7 bar

swell

Commons : Challenger I  - collection of images, videos and audio files

Individual evidence

  1. ↑ Erik Arneson: Mickey Thompson. The Fast Life And Tragic Death Of A Racing Legend , excerpt from "highperformancepontiac.com"
  2. ↑ Challenger I - 1959 , Internet portal "thompson-motorsports.com" ( Memento from November 30, 2010 in the Internet Archive )
  3. ^ Up to Weißglut , Der Spiegel, No. 13/1963, p. 64
  4. ↑ Nobility obliged , Der Spiegel No. 40/1960, p. 88 f.
  5. ↑ Mickey Thompson , Internet portal "Taurtoisemotorsports.com"
  6. ^ Driver Killed in Bid for 400 mph on Salt Flats , The New York Times, August 2, 1960