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    In a period of almost 20 years, Porsche had worked itself up the motor sport ladder. From the early 1950s the Stuttgart based company slowly progressed through sportscar racing with increasingly sophisticated racers, and many class-victories in the process. After a brief spell in single-seater racing, their focus turned completely to sportscar racing with an overall win at Le Mans as the ultimate objective. This was achieved in 1970 with the 12-cylinder engined 917, which completely overshadowed the success of the 908/3 launched in that same year.

    The 917 was specifically designed for high speed tracks like Le Mans, whereas the 908/3 was designed specifically for the twisty Targa Florio and Nürburgring tracks, where sharp handling was more important than raw power. Following Colin Chapman's principle of 'adding less weight' and using the lessons learned developing the 909 hill-climb racer, Porsche put the existing 908 on a diet. Usually chassis rigidity suffers from weight saving, but the aluminium-alloy spaceframe designed for the 908/3 Porsche found the perfect balance.

    Another decisive factor in improving handling is the weight balance; a car turns in much easier if all the weight is centred around the car's centre of gravity. To achieve this, the air-cooled flat eight engine was mated to a five speed gearbox with the final drive and clutch at the rear. This allowed for the engine to be installed much further forward in the chassis. It also placed the driver almost between the front wheels with his feet sticking out beyond the wheel centre line.

    The flat eight engine was carried over from the previous 908s. With its three litre displacement, the twin-spark engine explored the prototype regulations to the maximum, something Porsche often chose not to do with previous designs. Although it was far from being the most sophisticated 3-litre racing engine available, the 360 bhp delivered an incredible power to weight ratio; each horse having to propel a mere 1.56 kg. That power was transferred to the wheels through a five speed gearbox, bolted directly onto the rear of the engine.

    To make the 908/3 as nimble as possible, the front and rear overhang were kept minimal. With the engine being cooled strictly by air, there was no need for a big radiator to interfere the airflow over the body. The result was a very simple and clean design. Continuously under development, the design gradually evolved, with the most obvious change the addition of fins on the corners of the rear bodywork ahead of the 1971 season. Although the body was all-enveloping, it weighed little over 12 kg, adding next to nothing to the overall weight.

    In its debut year of 1970, the Porsche 908/3 scored victories in the two races it was designed for; the Targa Florio and the Nürburgring 1000 km races. Unfortunately these fine results were left in the dust, behind the racing headlines that Porsche finally won the 24 Hours of Le Mans race. In the next season the 908/3 faced stiff competition from Ferrari and Alfa Romeo. Their racers featured Formula 1 inspired four valve per cylinder engines, which were far more advanced than the Porsche's eight cylinder.

    Porsche was clearly down on power, but the 908/3's exceptional low weight meant it could stay on pace with its heavier competitors. At the Targa Florio, the entered 908/3s suffered from bad luck, leaving an easy victory for one of the Alfa Romeo Tipo 33/3s. Porsche bounced back with a 1-2-3 finish on the Nürburgring after the more powerful Ferraris and Alfa Romeos had failed under pressure. Again the 917's results pushed the Porsche 908/3's victories into the margins of the history books. Following a rule change, Porsche withdrew from the World Championship at the end of the year.

    The racing career of the 908/3 was far from over as several were sold to privateers and raced successfully for another decade! Some of the most successful of these were the examples raced by Reinhold Joest. He had at least one example equipped with a Turbocharged 2.1 litre 6 cylinder, producing over 200 bhp more than the original 8 cylinder unit. With minor reinforcements the lightweight chassis coped with the additional power surprisingly well. Porsche applied the lessons Joest learned with the Turbocharged 908/3 when developing the mechanically very similar 936, which would score three 24 Hours of Le Mans victories.

    Like many Porsche racing car designs, the 908/3 did what it was designed for: win. Compared to the much more powerful, but ill-mannered 917, the 908/3 was a much completer package and a lot easier to drive. Long after its original challengers were retired from active racing, the 908/3 remained competitive, underlining the great design that the 908/3 is.

    Porsche constructed 11 cars ahead of the 1970 season and a further two were built using a slightly lighter frame for 1971. Of the first batch quite a few were used for testing and development only. Most chassis have survived and are today regularly raced in historic events all over the world.

    The Gulf colour scheme on this 1970 Porsche 908/3 makes it an instant favourite around this part of the internet, interestingly this is just the 4th of 13 examples built during 1970. This chassis was used exclusively for flex-testing and was never raced, making it (probably) the most pristine example in the world.

    She’s fitted with a howling 350hp, 2,997cc, double-overhead cam, air-cooled (!!!), flat 8-cylinder engine with Bosch mechanical fuel injection, a 5-speed manual transaxle, 4-wheel independent suspension, and 4-wheel disc brakes.

    The Porsche 908/3 was the car created by Porsche specifically to race and win in just 2 races, the Targa Florio and the Nürburgring 1000. The insane Porsche 917 was considered too heavy and tail happy to race on the tighter, more twisty circuits and so Porsche revived the 908 and set about creating a car capable of taking on all comers at the world famous Nürburgring and wiping the floor with them.

    In 1970 Jo Siffert and Brian Redman used a 908/3 to take 1st place at the Targa Florio for Wyer’s Gulf team, 2 other 908/3s placed 2nd and 5th. At the 1970 Nürburgring 1000 the car continued its winning ways finishing 1st and 2nd by a significant margin.

    In 1971 Porsche pulled the cars out of storage, race-prepped them and then took 1st and 2nd place at the Nürburgring 1000 – widely considered to be one of the toughest races of the era. The cars carried on winning races until the early 1980s and went a long way towards cementing Porsche’s reputation as a world-class racing car manufacturer.

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  • 05/28/13--09:59: Royal Enfield Sprint

  • W. Dyke and his 692cc Royal Enfield at the Ramsgate Sprint.

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  • 05/28/13--11:00: Homo Cathectus

  • The monkey mascot of London's Crystal Palace Speedway helps a mechanic tune a motorcycle belonging to a member of the 1932 English motor racing team.

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  • 05/29/13--09:00: Grumman XF5F-1 Skyrocket

  • Ordered as a prototype on 30 June 1938 by the US Navy Bureau of Aeronautics, the XF5F-1 was of radical concept. It was intended as a twin-engined shipboard fighter, and this at a time when the first single-engined shipboard fighter monoplanes were only just commencing flight test.

    The Grumman G-34 proposal of 1938 for a single-seat twin-engined shipboard fighter anticipated the realization of an operational production example of such a type by quite a few years. In fact, the proposal was then considered to be so advanced that it bordered on the revolutionary; yet only four years later, on 18 April 1942,16 North American B-25 twin-engined bombers were flown off the USS Hornet to attack Tokyo.

    Not only was the G-34 an advanced concept, in its original form it was a most unusual-looking aircraft, with the leading edge of its low-set monoplane wing forward of the fuselage nose. The tail unit had twin endplate fins and rudders, and the landing gear was of the retractable tailwheel type, with the main units retracting aft into the wing-mounted engine nacelles. Powerplant comprised two Wright R-1820 Cyclones, each with a three-bladed propeller, these being geared to counter-rotate to offset the effects of propeller torque.

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  • 05/29/13--11:00: NSU 250 Sportmax IOM TT

  • The NSU Sportmax is a racing motorcycle for private riders that was developed from the standard machine. It successfully raced alongside the factory Racemax machines from as far back as 1953. The whale cladding with ears was replicated many times by private persons, a practice that was tolerated by NSU provided it was not painted blue.
    In 1955, H.P. Müller riding the Sportmax became the world's first private rider to become world champion in the 250 cc class.

    Engine: 1-cylinder, 4-stroke
    Displacement: 247 cc
    Power: 28 hp at 10,000 rpm
    Maximum speed: 212 km/h
    Series: 1954-1956

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  • 05/30/13--08:04: Touring Superleggera Atelier

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    Among many of Elvis Presley's prized cars was his Stutz Blackhawk's. Elvis was the first person to own a Stutz Blackhawk, and probably his favourite car of the 1970s was his 1973 Stutz Blackhawk III.

    The Stutz Blackhawk was built on a Pontiac Grand Prix chassis, chosen for the GP's engine placement far back on the frame. In 1969 GM introduced a new 'A-special' platform with an exclusive 118 inch wheelbase which was later named the G-body.

    So the Stutz Blackhawk started life in the United States as a Pontiac Grand Prix. It was then shipped to Italy to be converted. Only the engine and transmission were kept as the body was stripped away and a new body and coach work added - by hand - not machine, to transform the car into a Stutz Blackhawk.

    The very first Stutz Blackhawk prototype was produced in 1969. The Stutz-founder, Mr. James D. O'Donnell, drove this car. Mr. O'Donnell bought the first Pontiac Grand Prix on October, 1st, 1968 that was shipped to italy and converted into the very first 'Stutz' prototype.

    The second Stutz prototype was built in the Padane factory, Italy in 1969/1970, being completed in April 1970.

    This was the first Stutz Blackhawk ever sold, and to none other than Elvis Presley.

    The most significant detail of the prototypes compared to the production cars that were produced starting in 1971, was the big rear-window. Only the two prototypes had the large size rear window.

    The interior of the Stutz was very luxurious. The floor coverings were made of Australian lambs wool. Twenty four karat gold plates the bezels and moldings. Only the finest European leather covered the seats, and was used on the dash. The dash also consisted of beautiful English burl. The Stutz went through a six week long process with twenty-two coats of individually hand rubbed lacquer paint

    The Stutz consisted of a GM TH400 transmission and GM 455 cubic inch V8 engine. With a horsepower of 425 the Stutz accelerated to sixty miles per hour in 8.4 seconds. The top speed of the Stutz was one hundred and thirty miles per hour. Fuel economy was just 8 miles per gallon.

    Elvis was interested, and Mr. Meyers told him that he could sign a contract, and that the Stutz-Company will build him his Blackhawk during the following months. Elvis wasn't interested in signing a contract, he was interested in buying the car, the car standing next to him.

    Jules Meyers tried to explain that this car was the very first Stutz, that he needed the car to show to potential buyers, to drive around, showing the beauty of the car. Elvis answered with a question: 'How do you think you will sell more cars, when you drive it, or when the people see ME driving it around?' Well, Jules saw the point ... Elvis got the car although it was shown at a motor show prior to delivery.

    Jules Meyers: Elvis wanted to have the car, I told Elvis that there was a car show, in a couple of days, and that I would need the car for that. It was O.K. with Elvis, so the car was sold. Elvis also agreed to take some press-pictures with him and the car - good for publicity. Frank Sinatra was also interested in the car, but Sinatra would not agree to any pictures of the Stutz being taken with him and he would not agree to the car being displayed at the car-show. So it was obviously the better decision to sell the to Elvis Presley.

    Elvis then immediately turned the car over to George Barris to further customize it. Elvis had for many years, had several motor vehicles designed and coach built by his friend, 'The King of Customizers' George Barris.

    Once George Barris had completed his work, the car was then delivered to the International Hotel in Las Vegas on Oct. 12, 1970 accompanied by a letter on Stutz Company letterhead verifying delivery to the International. Sonny West took delivery as Elvis was in Memphis on that date but Elvis soon flew to Las Vegas to see his completed new car.

    Unfortunately, this first Blackhawk car was involved in an accident on July 1, 1971 and the front was heavily damaged. Elvis had sent Sir Gerald, his L.A. chauffeur, out to have the car washed and it ended up in an accident. After that, Elvis put it in storage. Repairs to the car were not completed until the early 80s. Mr. O'Donnell, the founder of the new Stutz company helped to restore the car, after earlier advising that the car was 'a total wreck' and the only value this car now bears is one of salvage' and offered $1,000 for it in a written letter to Vernon Presley dated August 2, 1971. Being a prototype original parts were not available so the radiator grill and the front lights fitted are not original.

    In April of 1973, Elvis made a surprise visit to the Pontiac Dealership from whom he had purchased his first Black Stutz Blackhawk, back in 1970. He saw the new Pearl White Stutz displayed in the showroom window...they proudly showed Elvis the Stutz that was on display. Elvis placed an order for the car, that would be imported from Italy and delivered later that year to his Holmby Hills estate on Monovale Drive in Los Angeles. Elvis' new Stutz was delivered at 4 p.m. in the afternoon. Elvis had just woke up, but he happily agreed to pose for publicity photos with the dealership owner, Jules Meyers.

    The most famous Elvis Stutz is the 230 HP, 1973 Stutz Blackhawk III, purchased on September, 6, 1974. This Stutz was very unique because it had a red leather interior with 18-karat gold-plated trim throughout.

    The 1973 Stutz Blackhawk III was without doubt Elvis' favourite car in the '70s. In fact the last known photograph of Elvis was taken as he was driving though the Graceland Gates in this car shortly after midnight on August 16, 1977, from a late-night visit to the dentist.

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    The Cafe Racer scene in Indonesia is alive and kicking. Despite the unavailability of large capacity motorcycles and the high expense involved with purchasing parts from other countries, skilled builders are fabricating their own parts to meet customer demands and the resulting build are nothing short of world class. This is the second Cafe Racer build to roll out of Studio Motor in Jakarta. Back in June they released their 1954 Matchless Cafe Racer which had us eagerly waiting for more and they certainly haven't disappointed. This is the Studio Motor M33 BSA based, Norton Manx inspired Cafe Racer.

    Using images sourced from the internet shop owner Donny Ariyanto set about building the bikes bodywork from scratch. The tank was hand fabricated in 1.2mm steel to match the Manx style as closely as possible with only photographs as a reference point. Dimensions were modified to suit the smaller BSA frame and a "wasps tail" cowl was fabricated to hug the shortened rear loop.

    The BSA's original rims have been upgraded to TK wheels imported from Japan which are wrapped in classic Firestone Champion Deluxe rubber. Front and rear drum brakes provide plenty of stopping power for the 500cc single and go perfectly with the bikes classic look.

    The front suspension comes from a Yamaha Byson (Indonesian 153cc sports bike) while at the rear Donny has used the same retro styled Red Wing shocks we saw on his Matchless build. A set of clip on bars from a Honda CBR400 with only the bare essential controls cling to the top of each fork tube and a Bates style custom headlight sits between them, mounted on the lower triple tree.

    Upgrades to the M33's performance come in the form of a KOSO carb jetted to suit the open stack and a Jet Hot stainless steel muffler free the exhaust gases. The tank has been finished in classic Norton Manx silver with black/red pins by local spray painters Comet Studio with the British Small Arms winged emblem emblazoned on it's sides. Well done sir, my hat comes off to you.


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  • 05/31/13--11:00: Fill me up!

  • 1972 Italian GP Lotus 72D Emerson Fittipaldi

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    In 1963, a little over a year after their successful '24-hour at 100mph' record (using a 500cc Venom), the Veloce factory decided to make a second attempt at a 24-hour record, using a 350cc 'Viper' model, which had been specially tuned for the purpose. This unsuccessful attempt has gone under-reported in past publications, as a footnote in history, but I think it brings the success of that 1961 attempt into higher relief, showing just how many factors must go right to pull off such a feat. [top photo, Veloce Managing Director Bertie Goodman at speed]

    Both attempts took place with an Anglo-French team at the Montlhéry speed bowl, a 2.7km concrete track (still extant, although perhaps not for long... this track is as historic as Brooklands, and must be saved!), with a notoriously bumpy surface (to which I can attest, having blasted a MkVIII KTT Velocette on the banking in 2000), and rather poor facilities, especially track lighting. Obviously, if a machine is to be run for 24 hours, the track needs to be lighted, and Montlhéry is distinctly dark at night, being outside the small suburb, and in a forest. Both attempts used rows of parked cars with headlamps ablaze, to light the track at intervals - notably dangerous when you consider that each 'beam' was a perpendicular flash of light at 100mph, creating a dizzying stroboscopic effect. During the earlier Venom 24hr ride, a French rider became so disoriented late he ran off the track, derailing the whole exercise for half an hour, while the machine was sorted out. The team still had time in hand, and just squeaked over the magic 'ton', at 100.05mph for the 24 hours.

    The Viper model as standard shares the cycle parts of the 500cc Venom, as was common in the cost-cutting British industry at the time, so it bore a weight handicap relative to its larger brother, at 380lbs. And while the Venom is 'square' at 86mm bore/stroke, the Viper is decidedly a long-stroke, using 72 x 86mm dimensions (a 'sleeved-down' Venom engine, with smaller combustion chamber, valve size, and inlet tract/carburetor).

    The 350cc Viper used in the 1963 attempt was a very special machine, and hardly 'standard'. The most radical departure from catalog spec was a dry-sump gearbox with an oil pump, which sprayed oil from jets onto the gears, then recirculated the lubricant, to keep the oil cool and reduce drag, and saved a few horsepower. The TT carb had its float bowl remotely mounted on the oil tank, a la the pukka racing KTT model, the exhaust valve was filled with sodium for cooling, an unsilenced reverse-cone megaphone, and full Avonaire racing fairing (adding 6-10mph to the top speed) were used. The piston was a specially sand-cast item shaped to give a 10:1 compression ratio (the 24-hr Venom used 8.75:1). This piston eventually put paid to the whole attempt, when the crown separated from the body above the gudgeon pin.Ivan Rhodes speculates that the ignition misfires and a fairing bracket which partially masked the cylinder head could have raised temperatures enough to cause failure of the piston. In any case, the two difficulties encountered during the attempt - a misfire from the magneto and the broken piston - were from components not made by Veloce! Small consolation for a failed attempt.

    The Viper was more comfortable than the '61 Venom, as the front forks now had both compression damping and rebound damping; this 'extra' was recently introduced to their sporting 'Clubman' models, and really helped over Montlhéry's bumps. The steering and true-running were faultless, even when airborne over those bumps at over 100mph.

    The machine was geared to reach 110mph (176km/hr) at 6500rpm, and after 6 hours, the Viper had an average speed of 104.7mph; faster thus far than the '61 Venom. The hourly average, excluding pit stops of 75 seconds each, was 105.1mph, which was fully 23mph faster than the existing class record, established in 1961 by a 175cc Bultaco two-stroke.


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    Publicity shot for The Wild One.

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    Victor had his first GP podium in 1973 at Hockenheim in Germany riding his 350 Yamaha to second place behind Teuvo Lansivouri. At the Italian GP at Monza that year he was involved in the tragic accident that took the lives of Jarno Saarinen and Renzo Pasolini. A fall at the Yugoslavia GP in June led to him missing the rest of the 1973 season and part of 1974. He won his home 350GP at Montjuic in 1974. In 1975 he competed in the 250 (3rd at Hockenheim and 4th at Andersdorp) and 350 championships (3rd at Brno ) on the revolutionary monocoque SMAC Yamaha of Eric Offenstad, and F750 on a TZ750 Yamaha, combining several podiums with numerous mechanical problems.

    In 1976 Victor rode for the Freddy Swaep team, with uneven performances in the 250, 350 and 500 classes. He also competed in F750 championship on a TZ750 Yamaha, coming second at the controversial Jarama event. In the latter part of the season problems with the team meant he had nothing to ride for the race at Silverstone but Sonauto Yamaha gave him the injured Patrick Pons bike. Victories in the next two races at Assen and Hockenheim meant he won the Formula 750 European championship, just two points ahead of the American Gary Nixon and his Kawasaki.

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  • 06/03/13--09:00: Pythagoras

  • A squared + B squared = C squared. Pythagoras’ name has an obvious place on one side of a triangle, but what’s not so well known is how it got there. Ed Foster is already a legendary Tuscon frame builder, but this street track frame is the product of his progeny, Preston Taylor.

    Ed was an ideal sensei for an enthusiastic student and began tutoring Preston in 2011. “I had a vision of what I wanted to build and Ed showed me how,” Preston tells us. “Over the past two years I honed my skills at La Suprema. Ed taught me everything: I was a sponge and absorbed everything I could.”

    Preston’s final goal was clear: “I really knew what i wanted before I started building, like the straight chain stays and the classic sized tubing. I also went with a Japanese haiku translated to English on the bottom bracket because it’s my first and to me, it’s timeless so it doesn’t need a number.”

    ‘Pythagoras’ is consistent with every frame guided by Ed’s hand: Tough and as gritty as the wild west they blow in from, with a prevailing artistic and philosophic influence. “I would also like to give Ed Foster a huge thank you,” says Preston, “and Aaron Panone for his 44rn chain ring also.”


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  • 06/04/13--09:00: Chaparral 2J The "Fan" Car

  • The Chaparral 2J, known as the 'fan car', or 'sucker car', was the first of only a few race cars to feature fan-assisted aerodynamics. It was powered by a powerful aluminum-block 8.1 litre Chevy V8, which was mounted to a custom 3-speed automatic. The automatic transmission was unique enough in itself: It was basically a 3-speed manual transmission with a torque convertor in place of a clutch. Each gear was selected in a similar manner to a manual transmission. However, by eliminating the clutch, the driver could use his left foot exclusively for braking, aiding concentration. Only three gears were available, but their ratios were similar to 3rd, 4th, and 5th gears on a conventional 5-speed transmission. This meant the car took some time to reach a decent speed, as it pulled off from a standing start in the equivalent of 3rd gear.

    The car was basically a giant vacuum-cleaner on wheels; a movable skirt beneath the car sealed in the vacuum created by two large fans mounted at the rear. The whole system worked something like a hover-craft, only in reverse! The area encompassed by the skirts started just behind the front wheels and completely enclosed the rear wheels. It covered approximately 2/3rds of the area of the underside. The skirt consisted of seperate sections made of a durable synthetic material called Lexan, similar to plexiglass. Each section articuled indpendently to the aluminum monocoque chassis, and was held down onto the road surface by springs. This was to ensure the best seal between the chassis and the road surface, even over undulating race tracks.

    The two 17-inch diameter fans were powered by a single 45hp, 274cc, 2-cylinder JLO Rockwell snowmobile engine, which ran at constant speed. This means the downforce created by the vacuum was near-constant at all speeds, unlike conventional aerodynamics which created exponentially more downforce as speeds increased. This method was preferred to the alternative of powering the fans from the engine, as the downforce would have varied slightly with the revs, which, considering the car only had 3 speeds, might have varied quite a bit. The snowmobile engine was mounted above the transmission and protuded slightly above the rear bodywork.

    The vacuum-traction system was extremely effective at forcing the car onto the road, resulting in increased acceleration, braking, and cornering speeds. As a side benefit, the large amount of volume contained within the underside of the car and the sides of the skirt acted as a vacuum 'reservoir', allowing the driver a little time to respond if the fans suddenly cut-out. This was a lot safer than the previous generation chaparral, which would have lost traction instantly if the rear-wing failed, which unfortunately was most likely to occur at high cornering speeds.

    The chassis (apparently) consisted of square-membered alumninum tube framework with aluminum panels. Once the cooling air had flowed through the forward mounted radiator, it was expelled over the top of the car. This was done to ensure adequate airflow and prevent interference with the vacuum traction system.

    The classis burble sounds emitted by the chevy V8 as it was run through the gears, in combination with the rasping snowmobile engine and the constant-pitch whine of the vacuum fans, made the car sound quite extraordinary. The car would visibly 'squat' as the fans powered up for the first time, and the vacuum system generated so much downforce at low speeds that wheel-spin from a standing start was virtually eliminated, even with over 700hp on tap! With enclosed rear wheels and two fans protuding out the back, the 2J looked and sounded like something out of science fiction, and its performance around the racetrack was equally unreal.

    A quote from Jim Hall (Chaparrals main driver): "The 2J's major advantage is that it will corner faster on low-speed corners, the ones that are 30 to 90 mph in normal Can-am cars. these corners predominate on Can-Am tracks. It means you can leave the corner faster, with more speed, and carry that speed down the straight." The vacuum-traction system allowed the chapparal to generate up to 0.5 g more lateral acceleration during cornering; at all speeds. Hall: "At first, the 2J was a real shocker! Side forces (in cornering) are really impressive. Holding your head upright becomes extremely difficult. On a normal Can-Am car you have to bend your head over about half-way to balance the cornering force. In the 2J the cornering forces want to bend your head right over. We're going to have to get used to it. I've banged my elbows and knees on things I never used to touch. Another change in the 2J performance over past models is the quickness and directness in steering. You get a direct change in direction when you turn the wheel. The downforce increases the contact load between the tires and the road without increasing the mass of the car. Steering effort is high and any little change causes a significant side force.", "I simply can't believe the braking capability of this car.", "It feels like it will decelerate about twice as fast as any Group 7 car I've driven."

    Text by: Michael J. Bloxham.

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  • 06/04/13--11:00: R J D Burnie's Norton

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  • 06/05/13--09:00: XB 70 Valkyrie

  • With research and development studies beginning in 1955, the XB-70 was a large, long-range strategic bomber was planned to be the replacement for the B-52. As in the B-58 program, the Air Force wanted new technology advances. To this end, the Air Force gave the prime contractor total weapon system responsibility. Competition between Boeing and North American for the contract occurred during the design phase. In 1958, the North American design was chosen and a development contract awarded. The Air Force requirement was for a Mach 3, high-altitude, long-range bomber capable of carrying nuclear and conventional weapons.

    Although there was a technology breakthrough in 1957 that made Mach 3 possible, the XB-70 never went into production. The continuing emergence of new SAMs was the key factor in the demise of the XB-70, just as it affected the B-47 and B-58.

    The XB-70 had a length of 196 feet, a height at the tail of 31 feet, and an estimated maximum gross weight of 521,000 pounds. It had a crew of four: pilot, copilot, bombardier, and defensive systems operator. The delta wing had a span of 105 feet with six turbojet engines side by side in a large pod underneath the fuselage. The wing was swept at about 65 1/2o, and the wing tips were folded down hydraulically 25o to 65o to improve stability at the aircraft's supersonic speeds of up to Mach 3. At this speed the Valkyrie was designed to ride its own shock wave. A large canard foreplane near the front of the fuselage with a span of 28 feet, 10 inches was used for stability. In addition to its sharply swept delta wings, the XB-70s had two large vertical tails.

    The aircraft was fabricated using titanium and brazed stainless steel honeycomb materials to withstand the heating during the sustained high Mach number portions of the flights. The propulsion system consisted of six General Electric turbojet engines (J93-GE 3) with two large rectangular inlet ducts providing two-dimensional airflow.

    The entire mission (including return) was to be flown at Mach 3, but even then the aircraft was vulnerable to SAMs of the 1960's vintage. A high altitude, Mach 3 penetrator cannot maneuver well; its straight and level trajectory would have been an easy course to plot and intercept. Further, the technology that made Mach 3 possible yielded an airframe with a large RCS that added to the effectiveness of SAMs against the XB-70. The airframe was not adaptable to low level penetration to avoid SAMs because the delta wings were very thin and did not lend themselves to the structural modifications necessary for sustained, low level flight.

    The XB-70 design had payload flexibility but not mission flexibility. In 1959, the XB-70 concept was changed to a recon/strike RS-70, making it a reconnaissance aircraft with a bomber strike capability. However, its reconnaissance capability would not have been as good as the super high altitude aircraft designed to fill the reconnaissance role. The XB-70 was an aircraft which fulfilled the criteria it was designed to meet, but whose mission had been eliminated by defensive threat technology.

    The high drag of the Mach 3 airframe required a fuel load comparable to the B-52 but limited the range to about 5,000 nm. It was capable of carrying both conventional and nuclear weapons internally, but due to its design and Mach 3 mission profile, it could not carry external ordnance.

    In 1961, President Kennedy announced that the XB-70 program was to be reduced to research only, citing high cost (over $700 million per prototype) and vulnerability. The Kennedy administration felt ICBMs were more cost effective because they were less vulnerable and were cheaper operationally. Although two XB-70 prototypes were built, with the first flight in 1964, the program terminated in 1969. The XB-70 had speed, range, and adequate payload, but it was expensive, not suited to low level penetration, and thus did not compete with ICBMs for strategic funds.

    During the early 1960s, the NASA Flight Research Center was involved in support of the national Supersonic Transport Program (SST). Two prototype Mach 3+ high altitude bombers, built by North American Aviation for the Air Force, became available for SST research with the cancellation of their intended military program. Aircraft No. 2 (serial # 62-0207) with its improved wing design, was capable of sustained Mach 3 flight at altitudes around 70,000 ft. This highly instrumented vehicle was destroyed in a mid-air collision with NASA F-104N (N813NA) on 8 June 1966. An attempt to substitute the slower No. 1 aircraft (serial # 62-0001) into the research program met with limited success. Ship #1 was flown by the NASA Flight Research Center (now NASA Dryden), Edwards, Calif. from March 1967 through early 1969. The XB-70A program produced a significant quantity of information about supersonic flight up to Mach 3 speeds. In many areas, such as noise (including sonic boom runs), clear air turbulence, flight controls, aerodynamics and propulsion system performance and operation problems, it related to SSTs.

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