US3178223A

US3178223A - Airmen's seat harnesses

Info

Publication number: US3178223A
Application number: US229375A
Authority: US
Inventors: Martin James
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-10-11
Filing date: 1962-10-09
Publication date: 1965-04-13
Anticipated expiration: 1982-04-13
Also published as: GB959707A; DE1406581A1

Description

April 13, 1965 MARTIN 3,178,223-

AIRMEN'S SEAT HARNESSES Filed Oct. 9, 1962 2 Sheets-Sheet 1 A ril 13, 1965 J. MARTIN 3,178,223

AIRMEN'S SEAT HARNESSES Filed 001:. 9, 1962 2 Sheets-Sheet 2 United States Patent 3,178,223 AIRMENS SEAT HARNESSES James Martin, Southlands Manor, Southlands Road, Denham, near Uxbridge, Middlesex, England Filed Oct. 9, 1962, Ser. No. 229,375 Claims priority, application Great Britain, Oct. 11, 1961, 36,534/ 61 5 Claims. (Cl. 297-385) This invention concerns airmens seat harnesses.

An airmans harness frequently comprises two principal parts which may be separate or combined, namely, one part (usually called the parachute harness) which serves to connect the airman to his parachute and, where provided, to his inflatable dinghy and/or survival pack, and the second part (usually called the seat harness) which serves to retain the airman in his seat.

The present invention is particularly concerned with airmens seat harnesses and is applicable to independent seat harnesses and also to seat harnesses forming a part of a combined harness.

One defect of most conventional airmens seat harnesses is their failure to counter, effectively, the tendency for an airman to be displaced away from his seat cushion and/or parachute and/ or survival pack (all hereinafter included in the term seat cushion) as a result of inverted flight or when other negative-G conditions prevail, there being a serious danger that 'on the airman being so displaced, the seat cushion will move forwardly relatively to the seat pan to such an extent that, in the case of a pilots seat cushion, it may interfere with the movement of the control column of the aircraft in subsequent flying or so that, in any case, the weight of the airman will be transmit ted through the seat cushion to the front wall of the seat pan withthe consequence that this may be distorted and possibly torn and so present a marked danger to the safety of the airman, this being especially the case where the seat is an ejection seat and if ejection follows upon such displacement of the seat cushion.

Considerable efforts have been expanded in an endeavour to improve airmens seat harnesses in such a way that the aforementioned defect will be minimised and the airman be firmly held in his seat in an aircraft in the said adverse conditions but, so far as I am aware, no

really successful solution to the problem has hitherto been achieved, arrangements so far proposed being complicated and tedious to don and/ or reducing the comfort of the airman when seated.

It is at present customary for an airmans seat harness to include lap straps having their rear ends anchored to the seat pan so as to pass upwardly and forwardly around the buttocks of the airman and over his thighs, the front ends of such straps being adapted to be fastened directly or indirectly to a quick-release device or box (hereinafter referred to as a quick-release box) usually situated in front of the airman in the region of his navel. In many instances, for example in the case 'of aircraft ejection seats, the rear ends of the lap straps are releasably anchored to the seat pan and the airmans seat harness includes further straps which pass from the quickrelease box and around or over the upper part of the airmans trunk and/or over his shoulders before being connected releasably to the back of the seat at the upper part thereof.

With any arrangement in which lap straps pass upwardly and forwardly from the lower part of the seat around the thighs and legs of the airman to be anchored directly or indirectly to a quick-release box in front of the airman, there is still some freedom for the airman to move away from his seat cushion in inverted flight or in other circumstances in which negative-G conditions pre- "ice vail, with the consequential dangers that have hereinbefore been explained, for it will be appreciated that the said lap straps do not exert a direct pull on' the airman towards the base of the seat pan but exert a pull in a more or less diagonal manner from the region of the airmans navel towards the rear lower part of the seat pan, so that the front ends of the lap straps may pivot or are, for example as the aircraft is inverted, around the anchorages of the lap straps to the aircraft seat and so permit the airman to move away from his seat cushion;

According to this invention there is provided an airmans seat harness comprising a pair of lap straps having their rear ends anchored or adapted to be anchored to an aircraft seat and a pair of holding-down straps anchored or adapted to be anchored to extend upwardly between the airmans legs from laterally spaced-apart locations 'on the base of such seat, each lap strap being associated with an individual holding-down strap to constitute a strap pair one member of which extends through an eye at the free end of the other member and has its free end adapted for fastening by a quick-release box, one member of such pair having length-adjusting means.

Preferably the lap straps have eyes at their free ends and are equipped with length-adjusting means, the holding-down straps extending through such eyes and terminating in fittings for coupling to the quick-release box.

Thus preferred forms of seat harness in accordance with the invention comprise a pair of lap straps having their rear ends anchored or adapted to be anchored to an aircraft seat and a pair of holding-down straps anchored or adapted to be anchored to extend upwardly between the airmans legs from laterally spaced-apart locations on the base of such seat, each holding-down strap extending through an eye at the free end of the adjacent lap strap and having its free end adapted for fastening by a quick-release box and each lap strap incorporating length-adjusting means.

Although the said two holding-down straps may be entirely separate from one another and individually anchored to the seat, the two straps may conveniently be formed from a single length of woven webbing, the strap being anchored to the seat by being passed freely through a pair of laterally spaced-apart inverted U-shaped loops or equivalent means symmetrically arranged at the front of the seat so that the holding-down straps will, whentensioned, form an open loop of such dimensions as to reduce the danger of injury to the airman in the event of his being thrust forwardly with respect to the seat.

The invention may be embodied in seat harnesses for use with aircraft ejection seats, the harnesses in such cases being adapted to provide for release of the airman from his seat at the appropriate stage of an ejection sequence.

Thus in the case of an independent seat harness for use with an ejection seat the various straps (including the holding-down straps) of such harness may all be anchored to the seat by locks that may be opened, e.g. by a suitable automatic mechanism, at the appropriate stage in an ejection sequence to free the harness from the seat. Alternatively, the quick-release box may be utilised to free the airman from the seat harness during ejection, this quick-release box (and any other such box for fastening other straps of the seat harness) conveniently being adapted for operation during ejection by a suitable automatic mechanism.

In the case of a combined parachute and seat harness for use with an ejection seat, the various straps (including the holding-down straps) of the seat harness part of such combined harness may all be anchored to the seat by locks openable during ejection to free the harness from the seat.

In order that the invention may he more readily under- 6 stood one embodiment of the same will now be described by way of example with reference to the accompanying drawings in which:

FIGURE '1 is a perspective view of an airman seated and secured in an aircraft ejection seat by means of seat harness in accordance with the invention; and

FIGURE 2 is a front view of the airman, seat and harness of FIGURE 1.

The drawings show an airman 1 seated in an aircraft ejection seat 2 and secured in such seat by means of an independent seat harness in accordance with the invention.

The seat harness comprises a pair of chest straps 3, 4 which extend around the chest of the airman 1, a pair of

lap straps

5, 6 which extend from anchorages 7 at the sides of the seat pan 8 of the seat 2 about the thighs of the airman, and a pair of holding-down or anti-G straps 9, :19.

The chest straps 3, 4 are anchored to the back of the seat 2 and have their free ends fastened by a first quickrelease box 11 while the

lap straps

5, 6 terminate in eyes formed by

ring fittings

12, 13, respectively.

The holding-down straps 9, areconstituted by a single length of webbing that extends through spaced-apart inverted

loops

14, 15 on the front of seat 2, the ends of such Webbing extending through the

ring fittings

12, 13 respectively and being fastened by a second quick-release box 16.

In this particular embodiment, the quick-release boxes 11, 16 are mounted on a breast plate 17 and are adapted for automatic actuation, during an ejection of the seat 2, by a time-delay mechanism, diagrammatically indicated at 18, operating the boxes via

flexible cables

19 and 20. The

lap straps

5, 6 each have a length-adjusting buckle 21 by means of which these straps may be tensioned to the airmans choice. It will be appreciated that'tensiom ing of these straps also etfects tensioning of the holdingdown straps 9, 10.

It will be understood that the use of two holdingdown straps that are tensioned by the lap straps to form an open loop between the airmans legs serves to restrain the airman in a manner that is unlikely to lead to injury, against his being thrust forwardly with respect to the seat pan.

I claim:

1. For an aircraft seat, an airmans seat harness comprising: a pair of lap straps adapted to be anchored to the seat to extend about the airmans lower body and a pair of holding-down straps adapted to extend upwardly between the airmans legs from laterally spaced-apart locations on the base of the seat, each lap strap being associated with an individual holding-down strap, to constitute a strap pair, an eye at the free end of one member of each such pair, the other member of such pair extending through said eye; a quick-release box for fastening the free ends of said other members of the strap pairs; and length-adjusting means for a member of such strap pairs.

2. For an aircraft seat, an airmans seat harness comprising: a pair of lap straps adapted to be anchored to the seat to extend about the airmans lower body and a pair of holding-down straps adapted to be anchored to extend upwardly between the airmans legs from laterally spaced-apart locationson the base of the seat; an eye at the free end of each lap strap, each holding-down strap extending through the eye of the adjacent lap strap; a quick-release box for fastening the free ends of the holding-down straps; and length-adjusting means for each lap strap.

3. An aircraft seat having an airmans seat harness comprising: a pair of lap straps anchored to the seat for extending about the lower body "of an airman seated therein; a pair of laterally spaced-apart anchorages at the front of the seat base; an individual holding-down strap secured to each said anchorage; an eye at the free end of each said lap strap, the adjacent holding-down strap extending through such eye; a quick-release box for securing the free ends of the holding-down straps; and length-adjusting means for each lap strap.

4. The aircraft seat of claim 3, wherein said holdingdown straps are constituted by a single length of webbing.

5. The aircraft seat of claim 4, wherein said anchorages comprise spaced-apart anchorage loops through which said webbing length is threaded.

References Cited by the Examiner UNITED STATES PATENTS (1st add. to No. 805,814)

FRANK B. SHERRY, Primary Examiner.

Claims

1. FOR AN AIRCRAFT SEAT, AN AIRMAN''S SEAT HARNESS COMPRISING: A PAIR OF LAP STRAPS ADAPTED TO BE ANCHORED TO THE SEAT TO EXTEND ABOUT THE AIRMAN''S LOWER BODY AND A PAIR OF HOLDING-DOWN STRAPS ADAPTED TO EXTEND UPWARDLY BETWEEN THE AIRMAN''S LEGS FROM LATERALLY SPACED-APART LOCATIONS ON THE BASE OF THE SEAT, EACH LAP STRAP BEING ASSOCIATED WITH AN INDIVIDUAL HOLDING-DOWN STRAP, TO CONSTITUTE A STRAP PAIR, AN EYE AT THE FREE END OF ONE MEMBER OF EACH SUCH PAIR, THE OTHER MEMBER OF SUCH PAIR EXTENDING THROUGH SAID EYE; A QUICK-RELEASE BOX FOR FASTENING THE FREE ENDS OF SAID OTHER MEMBERS OF THE STRAP PAIRS; AND LENGTH-ADJUSTING MEANS FOR A MEMBER OF SUCH STRAP PAIRS.