G-Force: its a term youve heard many times to describe the gravitational force on a person or object, particularly when it is accelerating. This can refer to flight, spacecraft launches, or any other activity involving acceleration. Withstanding it is another matter entirely: supreme physical fitness is the arbiter. 

Its a culmination of factors, including the magnitude of the g-force, the length of time the subject has to with stand it, the direction from which it applies, even the posture of the body upon which it is acting. An instantaneous impact such as a slap may have no long-term effects, but long exposure of high g-forces could prove lethal. Among those who have to deal with high g-forces as a matter of daily occurrence are the pilots of fighter aircraft, astronauts and even professional motor-racing drivers, thanks to the speeds and rates of acceleration of modern racing cars.
Pilots, astronauts and racing drivers train for this, exercising the precise sets of muscles need to deal with the forces - neck muscles, for example. Physical condition is crucial, because existing health issues, especially cardiovascular matters, affect an individuals tolerance levels. If one is unprepared for experiencing high g-forces, the effects can range from impaired vision to black-outs to attacks of nausea. And industrial strength headaches, too. 

To give you an idea of how g-forces feel, merely sitting in your chair is equivalent to 1g. If youre lucky enough to catch a ride in a Bugatti Veyron, and the driver accelerates from 0-100km/h in the cars shattering 2.4s, you will know the force of 1.18g. Ride on one of the more frightening amusement park roller coasters, and the forces might reach 3.5g6.3g. 

Ramping it up to levels that really tax your fitness are the top fueller dragsters that set quarter-mile speed records  4.2g would be typical. But its not just about acceleration: deceleration, too, winds up the gs, with an F1 car under heavy breaking subjecting its driver to 5g. Beyond acceleration and breaking, there are high-speed changes of direction, as in a typical aerobatic plane or fighter jet: the forces reach into the region of 912g! 

There are upper limits, of course: the rocket sleds used to test both human and hardware reach forces of over 45g, but serious injury or even death become concerns at greater than 50g. Beyond that, youre looking at the forces acted upon bullets, rockets and artillery shells. 

One of Montegrappas pens underwent unintended g-force testing  not that we expect our writing implements to be employed with such great force  when our ambassador Jean Alesi flew out of Base 112 Reims on September 6, 2010, in a Mirage F1. The fighter aircrafts model number is eerily coincidental, for Alesi enjoyed a long and rewarding career in F1 motor racing. His years behind the wheel, at the pinnacle of the sport, prepared him to withstand the forces generated during the flight with the alacrity of the pilot controlling the Mirage, in an aircraft reaching Mach 1  or the speed of sound. 

After a glorious life in Formula 1 and a full-bore flight in the Mirage fighter jet, Jean revealed that he has now experienced the ultimate expressions of his true love for speed and adventure. Now, I m all set! Jean happened to have a Montegrappa pen in his pocket. We are pleased to announce that both Jean and the pen survived the experience without any ill effects.

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