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Green, Rush F
11-03-2000, 04:40 AM
Below is a list of the replies to my inquiry:

"We are looking for data on human tolerance to landing from extreme heights and/or high velocities. Relevant areas would include parachute landings, ski jumping, children's slides, hang gliding etc. If you know of any studies or compendia related to this subject, please contact me."

Thanks to all of those who replied.

Rush Green
Human Factors Design Specialist
Boeing Commercial Airplane Group
PO Box 3707, MC 03-PR
Seattle, WA 98124-2207
phone: 425-717-5215
fax: 425-294-6054
email: Rush.F.Green@Boeing.com

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Richard Snyder, David Foust, and Bruce Bowman, "Study of Impact Tolerance
Throughout Free-Fall Investigation", University of Michigan Highway Safety
Research Institute, Prepared for the IIHS, Final Report, UM-HSRI-77-8,
December 15, 1977.

It is old, but its individual case-studies cover a wide range of
fall-heights and injury severities. We have a long experience in research of ski jumping. Two references listed
below will give an answer to your question concerning ski jumping.

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Müller, W., Platzer, D., & Schmöltzer, B. (1995) Scientific approach to ski
safety. Nature 375, 455.

Müller, W., Platzer, D., & Schmöltzer, B. (1996) Dynamics of human flight on
skis: Improvements on safety and fairness in ski jumping. Journal of
Biomechanics 29 (8), 1061-1068.

Landing velocities in ski jumping are over 30 m/s in ski flying (distances
more than 200 m) but the perpendicular velocity (impact velocity) in 200
meter jump can be less than 4 m/s corresponding to the equivalent landing
height of about 0.80 m! This is because the flight trajectory is almost
parallel to the landing slope at the end of the flight. Impact velocity
increases dramatically if the jumper flies well to the curve of the landing
slope (beyond the critical point where the landing slope starts to curve).

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(Liebermann & Goodman 1991 in Ergonomics; Hoffman, Liebermann
& Gusis, 1997 in Av. Sp. and Env. Med.; Goodman & Liebermann, 1992
Vision and
Motor Control, Elsevier North Holland edited by Proteau & Elliot). Other
work
[Liebermann & Hoffman] on landing of paratroopers is in progress).

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Minetti A.E. L. P. Ardig~, D. Susta and F. Cotelli. Using leg
muscles as shock absorbers: theoretical predictions and experimental
results of human drop landing. Ergonomics 41(12): 1771-1791, 1998.

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Well, there *was* an article in the J Am Vet Med Association a few years
back out of Animal Medical Center in New York, where they correlated extent
of injury to number of stories fallen in feline "second story syndrome"
(basically, falling off apartment windowsills in New York). Turns out the
cats hit terminal velocity at about 8 stories, and the extent of the
injuries was constant or went down (as the cat was able to turn) from there
on out. They had a good review of the literature there.

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