Guest

How Many G's Can A Person Withstand?

Sun Jun 11, 2000 1:37 pm

How many G's can a person withstand with out the G-suit on?
Can anyone with experience answer me that please.
thanx
 
Panther
Posts: 200
Joined: Thu Jun 08, 2000 3:17 pm

RE: How Many G's Can A Person Withstand?

Sun Jun 11, 2000 1:43 pm

I don't know how to answer that, but I know in an Extra 300 if you pull the stick all the ay aft at the right airspeed you can get up to 15 G's, A person @ 180lb would feel as if they were 3000lbs, I would hope you have on a preassure suit of some sort.
 
hmmmm...
Posts: 1959
Joined: Tue May 18, 1999 8:32 am

Geordi Laforge

Sun Jun 11, 2000 2:35 pm

Well, I doubt there are many people here with that type of experience. Most untrained, but young and healthy, people would black out at about 5-6 Gs. The old lady at the post office, 3 Gs. My mother, 2 Gs. A trained air force pilot might get 7-8 Gs before entering the land of Nod. A G-suit might increase this to I0 Gs. But the human body can survive much greater G loads.

In 1954, an air force researcher experimenting with the first high speed seat ejection systems, was subjected to 19 Gs in 0.07 seconds upon accelerating to 632 mph in 5 seconds. He was then stopped from that speed in 1.25 seconds. Subjecting him to 40 Gs.
He was no worse for wear.

Note the suit and tie. Very formal.





In Star Trek, Geordi Laforge kept the "inertia dampeners" working smoothly. These are needed to keep everything aboard the ship, including the ship itself, from tearing apart into atoms simply from the sudden acceleration to warp speed, which is many times the speed of light. How do these "inertia dampeners" work? Very well, indeed, evidently.


Hmmmm...
An optimist robs himself of the joy of being pleasantly surprised
 
Guest

RE: How Many G's Can A Person Withstand?

Sun Jun 11, 2000 3:10 pm

One of u said that the person pulled 40 g's for about 0.07 which means it was so fast that the person did not feel or even realize that he/she was having that much load. Of course, I know that even if it lasted for a half second or full second, it would just crush that person. That would be a wierd seen to look at.
 
Pbb152
Posts: 541
Joined: Sat Feb 19, 2000 2:57 pm

RE: How Many G's Can A Person Withstand?

Sun Jun 11, 2000 5:07 pm

As far as I know,a healthy human being would begin to experience a blackout at around 8-9 positive G's without any kind of pressure suit, and would begin to experience a redout at around 3-4 negative G's. The human body is much less tolerant to negative G forces than positive. When experiencing positive G forces, blood rushes from the head and upper part of the body to the lower extremities, and during negative G forces, blood rushes from the lower part of the body up to the head, hence the terms blackout and redout. This is as far as I know, and if I'm mistaken, feel free to correct me.
 
hmmmm...
Posts: 1959
Joined: Tue May 18, 1999 8:32 am

RE: How Many G's Can A Person Withstand?

Sun Jun 11, 2000 11:16 pm

He doesn't look crushed does he. The guy in the picture in my original post is he to whom I am referring. 19 Gs on acceleration. 40 Gs on deceleration. There is no difference between positive or negative Gs if you are travelling horizontal, as was this man on the Sonic Wind sled. 632 mph to 0 in 1.25 seconds. Water was used for braking purposes. The brave man's name was Col. John Paul Stapp, MD.

Hmmmm...
An optimist robs himself of the joy of being pleasantly surprised
 
mikeymike
Posts: 402
Joined: Thu May 18, 2000 6:52 am

RE: How Many G's Can A Person Withstand?

Mon Jun 12, 2000 8:36 am

FYI...

We dynamically test commercial aircraft passenger seats for all new model aircraft (i.e. 37 NG, 573, 674, and all 777) to 16g's. All aircraft seats (in the boeing catalog) are tested statically to 9g.

 
hmmmm...
Posts: 1959
Joined: Tue May 18, 1999 8:32 am

RE: How Many G's Can A Person Withstand?

Mon Jun 12, 2000 9:42 am

The
Space Center
Alamogordo, NM



Col. John Paul Stapp 1910 - 1999






Dr. John Paul (Col.) Stapp, surgeon, former Air Force Officer, was born in Bahia, Brazil, July 11, 1910. Dr. Stapp earned the title "The Fastest Man Alive" when he rode the famed "Sonic Wind I" rocket-propelled sled on December 10, 1954 to a land record speed of 632 mph in 5 seconds. Dr. Stapp sustained the greatest g-force endured by man in recorded deceleration tests up to that time.


Dr. Stapp died at his home in Alamogordo, NM on November 13, 1999.



Dr. Stapp was the son of the Rev. and Mrs. Charles F. Stapp. His preliminary education was obtained at the Brownwood High School, Brownwood, Texas. He received his BA degree in 1931 from Baylor University, Waco, TX and his MA degree form Baylor in 1932. Dr. Stapp received his PhD from the University of Texas, Austin, TX in 1940 and his MD degree from the University of Minnesota, Minneapolis, Minnesota, in 1944. He completed his medical internship at St. Mary's Hospital in Duluth, MN.

On December 23, 1957, Dr. Stapp married Lillian Lanese, a former soloist with the Ballet Theater of New York City. Dr. Stapp entered Military Service on October 5,
1944. He completed the Medical Field Service
School at Carlisle Barracks, Carlisle, PA and his
medical residency at the Regional Hospital, Lincoln
Army Air Base, Lincoln, NE. He was then assigned
to Pratt Army Air Base, Pratt, KS as a General
duty medical officer. Dr. Stapp attended the School of Aviation Medicine, Randolph Field, San Antonio, TX and
received his Aviation Medical Examiner designation.

On August 10, 1946, Dr. Stapp was transferred to
the Aero Medical Laboratory as project officer and medical consultant in the Bio-Physics Branch. His first assignment included a series of flights to test various oxygen systems in unpressurized aircraft at 40,000 feet. He was assigned to the deceleration project in March, 1947. It was during this deceleration project that Dr. Stapp rode the Sonic Wind I on December 10, 1954 to a land record speed of 632 mph in 5 seconds. The project was essential in improving the survivability of aircraft occupants in the event of a crash. Dr. Stapp has received wide acclaim for his development of safer seat belt technology.











Col. Stapp being
prepared for his famous
ride. Assisting him are
engineers and technicians
at Holloman Air Force
Base, New Mexico.
Stapp personally made 27
of the 73 manned sled
tests conducted as part of
the deceleration project.




The "Sonic Wind I" high speed sled is now on display at The Space Center. This is the sled that Dr. Stapp rode to record breaking speeds in the deceleration project. The sled reached 632 miles per hour, decelerating to zero in a second and a quarter (1¼ sec) with a force of more than forty Gs. His momentary body weight became 6,800 pounds. The wind blast at this speed was equivalent to a high-altitude ejection at supersonic speed.



A closer picture of the riding seat of the Sonic Wind I.


Out of these many sled runs came improved helmets, arm and leg restraints, better aircraft
seats, and stronger safety harnesses. Many lives have been saved thanks to Dr. Stapp's personal sacrifice and the dedication of the entire project crew. Dr. Stapp himself suffered several retinal hemorrhages, cracked ribs, and two broken wrists. The second broken wrist he set himself while walking back to the laboratory after a ride.



A rear view of the numerous rocket engines that pushed the high speed sled down the track.



A photo of Dr. Stapp at The Space Center. He was a frequent and most welcomed visitor to the Center.



The Bopper Sled (crash-restraint
demonstrator), a bungie-cord
powered short track sled with
controlled deceleration by means
of adjustable mechanical breaking
(in storage at the Museum
Support Center). The Bopper,
designed by Dr. Stapp, has been
used with dummy, animal, and
human subjects to study
deceleration with a variety of
safety restraints, at forces ranging
up to and slightly above
twenty-five g's.


You had balls of steel Dr. Stapp. I salute you. Godspeed.


Hmmmm...








An optimist robs himself of the joy of being pleasantly surprised
 
Pronto
Posts: 318
Joined: Tue Mar 28, 2000 12:43 pm

RE: How Many G's Can A Person Withstand?

Mon Jun 12, 2000 10:00 am

On most shows that involve an interview with a pilot who has suffered G-LOC(and survived, of course), it would seem the average(with a G-suit) is 7 Gs before blackout...and these guys are extremely heathly...
 
JAT
Posts: 1064
Joined: Fri Feb 04, 2000 4:45 am

RE: How Many G's Can A Person Withstand?

Mon Jun 12, 2000 10:09 am

I just want to congratulate all the people who replied to this topic. This is the kind of informative, educational , non-superficial topic that is becoming very rare on Airliners.net.

Keep it up!

JAT