Neg. And Pos. G Force In Aircraft

[Kedas]

Could someone explain/confirm the difference between pos. and neg. G forces.

 

I assume pos G is when your blood goes to your legs and neg G if it goes to your head.

and what are the pos and neg maximums for the human body?

[PG_Raptor]

Could someone explain/confirm the difference between pos. and neg. G forces.

 

I assume pos G is when your blood goes to your legs and neg G if it goes to your head.

and what are the pos and neg maximums for the human body?

Correct, positive Gs are where everything in the body weighs more, and, once enough g's are attained, blood becomes too heavy for the heart to pump well, and all the blood goes to your legs, causing a black-out. This is why G suits are important, the add pressure to your lower body so that the blood can't go there. Negative gs are the exact opposite, the blood goes up instead of down, causing a red-out, because your eyes get filled with excess blood.

 

As for the limits of the human body, they did some rocket tests on a guy, and found that the maximum to for most humans to still live is about 40G's front and back, 20 G's up and down, and about 10 side to side. 3 G's is aabout the most a peron can take for a ling time. Most people start to black out around 8-9 sustained, sometimes 10 G's. Some people, with training can stay concouis up to about 13 G's. But, the epitomy is some race car driver that hit a wall and went from like 90 to 0 in about 20 inches. I think it was calculated that he took about 127 G's :o

[+Fates]

Good explanation Raptor. I would like to add that the Federal Aviation Administration has recently required all new installation of passanger seating in commercial aircraft structure to withstand +16G's before failure. I think the old limit was only 9G's.

 

The FAA estimates the total retrofitting cost at $950.5 million, and the airlines aren't planning to get stuck with the bill.

 

Current 9G seating allows airlines to make a smaller, lighter product. This equates to being able to put more passanger seats into a given amount of space. Guess who's gonna pay for having stronger seats? You. Should you feel more comfortable? Probably not physically....but you should know that your survival chances have increased tremendously.

 

Cheers!

 

Fates

[Kedas]

Thanks for the explanation but I still have some questons. :)

 

Is there a total G's measurement in a cockpit (independant of direction)

 

For example if a figther lands/takes-off on a carrier than according to the definition the the G forces will be more or less zero because the blood wont go up or down. (but the horizontal acceleration wil be big)

 

So if he lands/crash on the carier does it register anywere can we see that anywere and were can we find these measurements in LOMAC?

 

If a pilot talks about 5G's does he/she mean the total G's?