Lotus Design Technology

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=50 BGCOLOR="#339933" TEXT="#080000"> <div> <B>Lotus Design Technology</B></div> <div> </div> </td> </tr><tr> <td valign="top" width=175 BGCOLOR="#336600" TEXT="#F7F7FF"> <div> <B>Lotus 78/79</B></div> <div> <B>1977-1978</B></div> <bR> <div> <B>Ground Effect</B></div> <div> <B>Aerodynamics</B></div> </td> <td valign="top" height=430 BGCOLOR="#00CC66" TEXT="#080000"> <div> <B>The Wing Car and the Ground Effect:</B></div> <div> <B>Chassis and Aerodynamic Design Interface</B></div> <bR> <div> The aerodynamics of the modern Formula I cars assumed critical importance. Body shape wasn't directed solely towards minimizing drag as it was before the middle sixties, since current engines allowed in Formula I produced an excess of power. Design challenges now looked towards increasing traction and cornering through aerodynamics without introducing too much drag. The late seventies saw various concepts being introduced to achieve these effects.</div> <bR> <div> In the late sixties Jim Hall in the Chaparral sports racer experimented in downforce by using first external wings and then fans to exhaust the air from underneath the car. High-mounted wings were tried in Formula I, but became unstable under certain conditions, resulting in crashes. The fan approach was also tried by Jack Brabham in Formula I until movable aerodynamic devices were banned. </div> <bR> <div> <TABLE BORDER="0" CELLPADDING="2" CELLSPACING="1" WIDTH="795" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 354 WIDTH="371"><div> The Lotus 72 wedge-shaped car of 1970 with front spoiler and low-mounted triple rear wing was one of Lotus' most successful cars - winning the World Championship in 1970 and the Constructor's Championship in 1973.  The 72 was actually campaigned with yearly upgrades for six race seasons - a record for a Formula I car. The 72's wings and wedge shape set the stage for improving cornering performance by body-generated downforce. This was achieved at the expense of a minor increase in straight-line drag. Photo: Dutch GP 1970, Jochen Rindt / Lotus 72.</div> </tD> <tD VALIGN=TOP><NOBR><div> <IMG SRC="5aea35c0.jpg" border=0 width="419" height="348" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> </TABLE></div> <bR> <div> In August of 1975 Colin Chapman took the wedge concept further in a now-famous 27-page document specifying his requirements for a new car. In this brief Chapman suggested the way to go in creating downforce with minimal drag and also listed the unknowns that needed to be investigated by his R&D people.</div> <bR> <div> A year-long series of windtunnel tests, resulting in some phenomenal downforces, provided the shapes and principles to be used. Racing loads in the form of cement-filled barrels were applied to every component as it was built to verify stiffness. </div> <div> <TABLE BORDER="0" CELLPADDING="2" CELLSPACING="1" WIDTH="789" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 390 WIDTH="371"><div> The car - Lotus 78 - had a slim fuselage, but with broad panniers or pods on the side. These housed water radiators within their leading edge openings, with hot air exhaust ducts opening on top. The undersides of the panniers curved upwards as did the upper surface. The panniers ended in front of the rear wheels. Vertical metal skirts extended downwards from the panniers near the rear wheels to separate the air flow underneath the car from that around the car. Beneath the car a low pressure region was formed that sucked it down onto the road. These features are visible in the photo at right of Mario Andretti at Monaco,1977.</div> </tD> <tD VALIGN=TOP><NOBR><div> <IMG SRC="5b095800.jpg" border=0 width="405" height="384" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> </TABLE></div> <bR> <div> The Lotus 78 with Andretti driving won four Grands Epreuves in 1977, but mechanical problems and engine failures in 8 other races kept him from garnering the world title. Champion Nicki Lauda and 2nd place Jody Scheckter both won three races each, but were more consistent in the other races. The World Championship system rewarded consistency more than winning. Chapman viewed Formula I as a laboratory for ideas and the lost championship didn't really bother him: "Merely driving for points isn't the name of the game, as far as I'm concerned," he was quoted as saying. The 'wing car' had materialized and, although a bit heavy and possibly a little slower on the straight, the drivers used all its tremendous downforce on the curves and corners to great advantage.</div> <bR> <div> The Lotus 79 for the 1978 season took the whole concept one stage further. The new car had improved air flow through the side panniers by deleting the outboard suspension springs and taking the gas tanks out of the panniers and into the car behind the driver. The panniers were bolt-on fiberglass with carefully-shaped top-exit cooler ducts and had an expanding venturi section at the rear to create a stronger pressure drop with the air exiting cleanly in front of the rear tires. Skirts sealed the entire air chamber below the car. This was 'ground effects' at its most devastating.</div> <bR> <div> The 1978 race season saw Mario Andretti win 9 of 16 races and the World Championship. On September 10 at Monza, Mario won the race, giving him the title. Lotus' co-driver Ronnie Peterson crashed on the first lap, breaking his legs. He died from a blood clot a few days later while in the hospital. The only other American to win the World Championship was Phil Hill in 1961. Hill also clinched his title on September 10 at Monza, after the death of his team mate Wolfgang von Trips who fatally crashed after touching wheels with the young Jim Clark. Tragic coincidences that took all of the joy of triumph out of winning the World Championship.</div> <bR> <div> <TABLE BORDER="0" CELLPADDING="2" CELLSPACING="1" WIDTH="807" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" ALIGN="BOTTOM" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 20 WIDTH="801"><div> <B>Mario in Lotus 79 - winning Belgian GP at Zolder, 1978</B></div> </tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 416 ><NOBR><div> <IMG SRC="5cd5e250.jpg" border=0 width="606" height="293" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <bR> <div> <A HREF="id267.htm" TARGET="_top" TITLE="Lotus Design Technology"><U>Space Frame</U></A>   <A HREF="id292.htm" TARGET="_top" TITLE="Lotus Design Technology"><U>Monocoque Elite</U></A>   <A HREF="id293.htm" TARGET="_top" TITLE="Lotus Design Technology"><U>Backbone</U></A>   <A HREF="id294.htm" TARGET="_top" TITLE="Lotus Design Technology"><U>F-I Monocoque</U></A>   <A HREF="id296.htm" TARGET="_top" TITLE="Lotus Design Technology"><U>Double Chassis</U></A>   <A HREF="id297.htm" TARGET="_top" TITLE="Lotus Design Technology"><U>Elise</U></A></div> <bR> <bR> <bR> </NOBR></tD> </tR> </TABLE></div> <bR> </td> </tr></table></body>