and decreasing tire pressure. Cars with unusual handling problems Certain vehicles can be involved in a disproportionate share of single-vehicle accidents; their handling characteristics may play a role: Early Porsche 911s – suffered from treacherous lift off oversteer (where the rear of the car loses grip as the driver lifts off the accelerator); also the inside front wheel leaves the road during hard cornering on dry pavement, causing increasing understeer. The roll bar stiffness at the front is set to compensate for the rear-heaviness and gives neutral handling in ordinary driving. This compensation starts to give out when the wheel lifts. A skilled driver can use the 911's other features to his/her advantage, making the 911 an extremely capable sports car in expert hands. Later 911s have had increasingly sophisticated rear suspensions and larger rear tires, eliminating these problems. Triumph TR2, and TR3 – began to oversteer more suddenly when their inside rear wheel lifted. Volkswagen Beetle – (original Beetle) senstitivity to crosswinds, due to the lightness of the front of the rear engine car; and poor roll stability due to the swing axle suspension. People who drove them hard fitted reversed wheels and bigger rear tires and rims to ameliorate. Chevrolet Corvair - poor roll stability due to the swing axle rear suspension similar to that used in the Volkswagen Beetle, and cited for dangerous handling in Ralph Nader's book Unsafe at Any Speed. These problems were corrected with the redesign of the Corvair for 1965, but sales did not recover from the negative publicity and it was discontinued. The large, rear-engine Tatra 87 (known as the 'Czech secret weapon') killed so many Nazi officers during World War II that the German Army eventually forbade its officers from driving the Tatra. Some 1950s American "full size" cars responded very slowly to steering changes because of their very large angular inertia, softly tuned suspension which made ride quality a priority over cornering, and comfort oriented cross bias tires. Auto Motor und Sport reported on one of these that they lacked the courage to test it for top speed, probably due to their familiarity with smaller European cars and their unfamiliarity with large American cars. Dodge Omni and Plymouth Horizon – these early American responses to the Volkswagen Rabbit were found "unacceptable" in their initial testing by Consumer Reports, due to an observed tendency to display an uncontrollable oscillating yaw from