Army restraint system

An arm restraint system for use with an aircraft ejection seat to prevent limb flailing on ejection. Long straps, which are normally loose to allow unimpeded arm and body movement of the seated crewman, are retained high on the side of the shoulder area by a flap with a Velcro fastener and by ring members on the seat buckle and on the seat frame. During the ejection sequence, the Velcro fasteners are pulled apart by the action of the straps which move downward and pin the crewman's arms against his side and lower abdomen thereby preventing flail upon entry of the crewman into the airstream.

BACKGROUND OF THE INVENTION 
This invention relates to an arm restraint system for attachment to an 
aircraft ejection seat and, more particularly, the invention is concerned 
with providing a system which includes a strap retention device allowing 
unimpeded arm and body movement until ejection at which time the straps 
are retracted causing the crewman's arms to be pinned against his side and 
lower abdomen during ejection. 
The restraining of an occupant's body from movement relative to his seat 
both prior to and immediately after ejection from a high speed aircraft is 
necessary in order to prevent possible physical damage caused by forces of 
the ejection gun or rocket acting on various parts of the occupant's body. 
Also, after ejection, extensive bodily damage can occur especially to the 
arms and legs when the windstream around the aircraft hits the body. 
Injury during ejection is greatly increased by the flailing of the limbs 
when subjected to ram air pressure which is encountered during the initial 
stages of ejection. Limb flailing can result in fractures, dislocations, 
traumatic amputations and/or other irrepairable physical limb damage. The 
danger is particularly acute in the case of arms because the airman may 
have an arm outstretched at the time of ejection and this arm would be 
subjected to the full force of the airstream on ejection. 
The present invention provides an arm restraint system suitable for use in 
an emergency escape situation wherein an ejection seat with the occupant 
seated therein is ejected from the fast moving aircraft. The system is 
capable of quickly pulling the arms of the airman to a safe position for 
protection from airblast which occurs immediately after ejection. 
SUMMARY OF THE INVENTION 
The present invention is concerned with providing an arm restraint system 
wherein long straps which are normally loosely retained to the crewman are 
retracted during seat/crewman ejection. A strap retention device in the 
form of a folded Velcro flap positioned in the shoulder area serves to 
hold the strap in place ready for operation during an emergency. During 
the ejection sequence, the restraint straps are retracted causing the 
folded Velcro flap to unfold thereby allowing the restraint straps to 
slide down the arm and pin the crewman's arms against his sides and lower 
abdomen. 
Accordingly, it is an object of the invention to provide an arm restraint 
system for use on an aircraft ejection seat wherein the seated crewman is 
allowed to have substantially unimpeded arm and body movement prior to 
ejection thereby maximizing crewman comfort. 
Another object of the invention is to provide an arm restraint system 
wherein the arm restraint strap is retained at a specific point on the 
shoulders of the crewman to allow for swift and reliable restraint strap 
release upon strap retraction with a low release force required. 
Still another object of the invention is to provide an arm restraint system 
wherein the strap retainer is not required to be attached directly to the 
crewman. 
A further object of the invention is to provide an arm restraint system 
which is capable of accommodating the 5th through 95th percentile 
anthropometric dimensions of USAF crewmen while allowing rapid crewman 
ingress and egress. 
A still further object of the invention is to provide an arm restraint 
system wherein the restraint strap is prevented from snagging on pencils 
and/or pens contained in the sleeve pockets of the crewman's outer 
garments. 
Another still further object of the invention is to provide an arm 
restraint system which is simple to produce and requires no unusual 
materials or processes. Also, the system is relatively unaffected by 
variations in temperature, atmospheric pressure, vibration, acoustic 
noise, electromagnetic radiation, humidity, salt fog and spray, sand and 
dust, explosive decompression, solar radiation and corrosive atmospheres. 
These and other objects, features and advantages will become more apparent 
after considering the following detailed description taken in conjunction 
with the attached drawings and appended claims.

DESCRIPTION OF A PREFERRED EMBODIMENT 
Referring now to the Figures wherein like reference numerals refer to like 
elements in both views, FIG. 1 shos a crewman 13 seated in a normal 
position in an ejection seat 15 of an aircraft. The crewman 13 is capable 
of performing all of the necessary movements required to operate the 
aircraft without hindrance from the device of this invention. Before the 
flight, the restraint strap 17 is passed through the first ring member 19 
fixedly attached to the side of the upper back rest of the ejection seat 
15. The strap 17 is then passed by an unfolded shoulder flap 21, down 
through a second ring member 23 attached to the crewman's seat belt 25, 
and back up to the unfolded shoulder flap 21. The flap 21 is then folded 
up so that the portions 27 thereon, which adhere when pressed together, 
form a loop in which the strap 17 is held. The strap 17 then passes 
downward between the crewman's arm and the arm rest 29 of the ejection 
seat 15 and through a third ring member 31 which is affixed to lower side 
portion of the ejection seat 15. The strap 17 is then passed back to the 
point of origin so that tension can be applied thereto. 
In FIG. 2, the strap 17 is shown pulled back in the retracted position. The 
previously folded shoulder flap 21 has unfolded as a result of the 
downward force exerted by the restraint strap 17 as it is retracted. The 
portions 27 of the flap 21 may be made of Velcro (Registered Trademark) or 
the like or any other suitable arrangement which would separate and allow 
the flap 21 to unfold when a force is applied thereto. The strap 17 then 
slides down the arm of the crewman 13 pressing it inwardly against his 
body. The section of the strap 17 between the second ring member 23 
attached to the crewman's belt 25 and the third ring member 31 pressed the 
lower part of the crewman's arm against his lower abdomen. The arm is now 
restrained so that no flailing can occur on ejection. 
The loop in the folded flap 21 suspends the arm restraint strap 17 therein 
so that the strap 17 can move laterally through the loop without dragging 
appreciably as shown in FIG. 1. The releasing force which is produced by 
the downward pull on the arm restraint strap 17, causes a shear load 
between the adhering surfaces 27 preferably made of Velcro or like 
material. When the flap 21 unfolds, the lower part thereof falls over the 
pencil/pen sleeve pocket of the crewman thereby preventing the strap 17 
from becoming snagged by covering the projecting ends of the pencils and 
pens. 
It should be noted that the hereinbefore described arm restraint system is 
resistant to fluctuations in magnitude and direction of gravity loading 
which is very important during aerobatic maneuvers and emergency 
situations. Also, the action of the arm restraint system is automatic and 
requires no effort or thought on the part of the crewman to initiate 
operation during the ejection sequence. 
Although the invention has been illustrated in the accompanying drawings 
and described in the foregoing specification in terms of a preferred 
embodiment thereof, the invention is not limited to this embodiment. It 
will be apparent to those skilled in the art that certain changes, 
modifications and substitutions can be made in the hereinbefore described 
invention, particularly with regard to the construction details, without 
departing from the true spirit and scope of the appended claims.