Physiological effects on the human body 1

[chicopee]

Need to find a website on the effects of the human body from impact (decelarative) forces such as the type incurred from parachutes opening to sudden stops by tethered lanyards while in free falls.

 

[rhodie]

You need John Stapp!

http://www.nationalaviation.org/museum_enshrinee.asp?eraid=5&enshrineeid=394

This guy abused his body for science on a 600 mph rocket sled, decelerating in 1.25 seconds! There are many reports derived from information he helped gather.

My only experience with sudden deceleration and a sudden stop from a fall came as a Boyscout during a rappelling exerise. I learned not to tie the harness so close to my groin. You talk about blinding pain. I thought I was a non-combatant in the whole reproduction department for a while afterward.

 

[SteveBull]

5 star nutter.

Great post. Thanks.

 

[Kiwikid]

You'll be lucky to find much on parachuting or bungy jumping. I doubt the affects (if any) have warranted much study.

I can personally attest to the fact that parachuting and bundgy jumping have no noticeable affect on the body. I had waaaaay too much adrenelin in the system to even notice such trivial things at the time.

Most likely sources are car manufacturers or labs that do crash testing. Military research on +/- forces on pilots is the other bet.

 

[chicopee]

kiwikid, what do you know about the effects on the human body from sudden stop when wearing a body harness connected to a lanyard hooked to an anchor point? The sudden stop would be from a 6' free fall.

 

[IRstuff]

Sounds like you and Haggis should get together:
thread507-84756

From my limited perspective, it would be desireable that the stop NOT be instantaneous, e.g., more like a bungee cord.

Having said that, seat belts do a pretty reasonable job with what appears to be very little stretch, with a stopping time of around 0.1 seconds.

TTFN

 

[GregLocock]

Seat belts stretch by hundreds of millimetres in a crash. The stitching is designed to fail progressively, to give a controlled buildup in acceleration.

Although automotive crash data may get you in the right ballpark, I'd have to say that since head rotation and femur compression are not significant factors in your case, that the data is unlikely to be directly relevant.





Cheers

Greg Locock

 

[Kiwikid]

Chico,

I did all my parachuting in the army many years ago. The worst affect of sudden stops was during the ground training phase.

We did quite a lot of tower jumps with a std harness with para straps which where attached to an overhead wire cable which acted very much like a flying fox. Overall fall distance was about 12'.

Before you jumped you had to make sure you had the family jewels positioned in a safe place - ie so they could not be crushed or pinched by the leg straps. The stop was fairly sudden and you certainly new about it. The fox cable had some give in it but not much - about 2' at most.

Actual parachuting is much more gentle - you slow down over a distance of about 100' depending on your velocity when the chute opens and the type of chute you have. Base jumpers have a very fast chute which snaps you back much faster than ordinary parachuting. Your weight is also a factor.

How it feels depends on 3 factors; velocity, deceleration distance and your weight.

What or why do you need the info?

 

[Sparweb]

This kind of "arrested fall" is common in mountain climbing. Climbers select ropes with enough stretch to absorb the energy if they should fall. Mountain climbers, arborists, window washers, helicopter sling rescuers, antenna maintenance, and many more jobs require climbing or being suspended from a rope.

Contact

http://www.samsonrope.com/

for just one of many suppliers of these kinds of ropes. They can tell you about who uses them and the standards they follow.

The NFPA, ANSI, and UIAA all have standards regarding the perfomance of ropes and harnesses that are used to restrain personnel. There's also an EN standard that seems to be the most "useful".


"Simplicate, and add more lightness" - Bill Stout
Steven Fahey, CET

 

[Sparweb]

Addendum:
There's also aircraft crash data in FAA and NACA reports, if you know where to look. I can dig a bit, if you're interested.


"Simplicate, and add more lightness" - Bill Stout
Steven Fahey, CET

 

[Stache]

The FAA has several Advisory Circular and TSO’s about this subject as follows:

1) Copies of SAE AS 8043, (Torso restraint system) may be purchased from the Society of Automotive Engineers, Inc., Department 331, 400 Commonwealth Drive, Warrendale, PA 15096.
2) Copies of ASTM B117-73, (Standard Method of Salt Spray (Fog) Testing), D756-78, (Standard Practice for Determination of Weight and Shape Changes of Plastic Under Accelerated Service Condition), and G23-81 may be purchased form the American Society for Testing and Materials, 1916 Race Street, Philadelphia, Pa 19102.
3) Copies of AATCC 8-1981, (Colorfastness and Crocking), and 107-1981, (Colorfastness to water), may be purchased from the American Association of Textile Chemists and Colorists, P.O. Box 12215, Research Triangle Park, NC 27709.
4) Copies of Federal Test Method Standard 191 Method 5906 may be purchased from the Commanding Officer, Naval Publications and Forms Center, 5801 Tabor Avenue, Philadelphia, PA 19120.
5) Federal Aviation Regulations, Part 21, subpart O, may be purchased from the Superintendent of Documents, U.S. Government Printing Office, Washington D.C. 20402-9325.
6) Advisory Circular 20-110, “Index of Aviation Technical Standards Orders,” may be obtained form the U.S. Department of Transportation, Utilization and Storage Section, M-4432, Washington D.C. 20590.
7) AC43.13-1B chapter 9 paragraph 9-46 (b) (1) (2)
8) HOW TO OBTAIN TSO's, write to the: U.S. Department of Transportation, Subsequent Distribution Office, Ardmore East Business Center, 3341 Q 75th Avenue, Landover, MD 20785. To have your name placed on our mailing list to receive future issuances of TSO's, notices for public comment on proposed TSO's or copies of proposed TSO's, write to the: Federal Aviation Administration, Aircraft Engineering Division (AIR-100), 800 Independence Avenue, SW., Washington, D.C. 20591.
9) MFG of restraint systems: Pacific Scientific Co. Product Support Group, Seven Center, 22715 Savi Ranch Parkway , Yorba Linda, Ca 92687 Telephone Number: (714) 283-0283 Fax Number: (714) 283-4722.
10) AC 21-34 SHOULDER HARNESS - SAFETY BELT INSTALLATIONS
11) AC 23.562-1
12) AC 25.562-1
13) TSO-C22 Seat Belt and TSO-C114 Restraint Systems
14) RELATED READING MATERIAL.
a. TSO-C22f, "Safety Belts," Technical Standard Order, Federal Aviation Administration, February 24, 1972.
b. TSO-C39a, "Aircraft Seats and Berths," Technical Standard Order, Federal Aviation Administration, February 24, 1972.
c. "Motor Vehicle Seat Belt Anchorages Test Procedure - SAE J384," SAE Recommended Practice, 1979 SAE Handbook, Volume 2, pp. 33.08-33.09, Society of Automotive Engineers, Inc., 1979.

For installations in normal category airplanes, apply a test load of at least 1530 lbs. (9g x 170 lbs.). For installations in utility and acrobatic category airplanes, apply a load of at least 1710 lbs. (9g x 190 lbs.). The load should be applied in the forward direction of the airplane longitudinal axis and held for at least 3 seconds without failure.

RELATED FEDERAL AVIATION REGULATIONS (FAR) SECTIONS.

Sections 23.561, 23.785, and 23.1413 of FAR 23; Sections 27.561, 27.785, and 27.1413 of FAR 27;
Sections 29.561, 29.785, and 29.1413 of FAR 29; and Sections 91.107 and 91.203 of FAR 91.


Denny

 

[unclesyd]

Forget about the body I bet you can't do the structural dynamics of either on your laptop.

http://bemil.chosun.com/movie link/SU-35.wmv

The file is somewhat slow to download and all the link has to be typed in the address bar.
I played it with IrfanView for a very nice size picture.

 

[BJC]

chicopee

These guys have everything you want.

http://www.usaarl.army.mil/

Long ago and far away I worked ( employed by LBJ for $225 a month ) in a place I we built a telemetery package for a jumper. It was a FM-FM telemetery package that tranmitted heart rate, GSR, blood pressure, respiration rate, EKG and ECG back to the ground. The ECG never worked very well either because of the low signal voltage or the fact that someone who jumps out of a perfectly good airplane doesn't have a normally functioning brain.
We also did live test with voulenteers riding a crash sled to determine the effects of added headweight during a helicopter crash. The added weight was the helmeted mounted gunsight for the Cheyene, a later variation is the one used on the Apache. Tought duty going TDY to Wayne State University for that.
Drop them a line they will probably talk to you especailly if you have something to share.
Everything above was written up and is probably still in their library even after 37 years.

 

[WKTaylor]

Check-out spec ASSE Z359.1 [Am Scty of Safety Eqpmnt]

Regards, Wil Taylor

 

[Sparweb]

Wil! Welcome back! It's been a while.

Steven Fahey, CET
"Simplicate, and add more lightness" - Bill Stout