US2099587A

US2099587A - -crash cause recorder fxx ai aircraft

Info

Publication number: US2099587A
Authority: US
Publication date: 1937-11-16
Anticipated expiration: 1954-11-16

Description

Nov. 16, 1937. s, G, ALLEN 2,099,587

CRASH CAUSE RECORDER FOR AIRCRAFT Filed Jan. 50, 1937 ATTORNEYS Patented Nov. 16, 1937 CRASH causa Mexicanen. rca s Sidney G. en, Raleigh, N. C.

Application .lanuary 30, i937, Serial No. 123,272

i Claims.

This invention relates to crash cause recorders for aircraft.

Hitherto whenever fatal aircraft crashes have occurred no positive clues have been recoverable from the wreckage to enable investigators to learn the cause of the crash and thus have an opportunity to correct faulty aircraft construction and prevent future loss of life and'property. The primary object of the present invention is to provide a recording apparatus which will only require the pilot to push a button corresponding` to an indestructible legend designating the approximate cause of a crash which is imminent, unavoidable and certain to happen, to the end that suchdata will be available to authorized persons examining the wreckage and such probable causes of future crashes may be remedied in future construction as well as in ships in current use.

A further object of the invention is to provide recording apparatus of this type including a shield which the pilot may instantly throw over the recording plungers to -prevent tampering as well as to protect the plungers against destruction by contact with wreckage. Y

A further object is 'to provide novel spring n pressed locking discs corresponding to respective recording plungers, shaped and arranged so that when the hawk bill of particular plunger is pushed into locking engagement with its respective disc it will be impossible to release the plunger until the apparatus is taken apart by investigators and at the same time when one plunger is pushed all remaining plungers are positively locked against being moved so that'l one cause, and only one definite cause, of an impending crash may be recorded by the pilot.

With the above and other objects in view the invention consists of certain novel details of construction and combinations of parts hereinafter fully described and claimed, it being understood (Gl. liti-135) leased position in full lines and in operative position in dotted lines.

Figure ti is a side elevation of the recording apparatus with portions broken away to expose the springs for forcing the shield latch into the latching groove of the cylinder. n

Figure 5 is a fragmentary perspective view showing the hawk bill of oneoi the plungers.

Referring now to the drawing in which like characters of reference designate similar parts in the various views, lll designates a cylinder which forms a housing for a plurality of annular locking discs ii which are conned in axial alignment in the bore of the cylinder by cap nuts i2 and i3 which are screw threadedly engaged in the ends of the cylinder and may be sealed in position by pins iti although other sealing means may be employed to prevent access to the discs by unauthorized persons.

The discs are mounted in the bore of the cylinder for limited movement endwise of the cylinder'and are' normally held stacked in contact with each other by a helical spring l5 seated in the recess of the cap nut i3 and exerting endwise pressure against the discs li to hold the same urged against a spacing washer it which abuts the mating cap nut i2, as best shown in Figure 2.

Each spring pressed annular locking disc il is provided in one end face with an inturned flange il and the peripheral edges of the disc are rounded off as shown at i8 in Figure 2 to provide a cam surface over which a respective recording plunger may pass to depress the disc against the tension of the spring i5, as will presently appear.

A plunger housing i9 is fixed to extend longitudinally of the cylinder it by screws 20 and pins 2l, passed radially through the plunger housing and into the cylinder, or other means may be used for forming a unitary assembly of the plunger housing and the cylinder. Projecting laterally from the intersection of the cylinder and the plunger housing is a substantially rectanguiar panel 22, in the present embodiment or the invention the panel being interposed at one longitudinal edge between the cylinder and theV plunger housing and being secured in place by the above mentionedscrews 20 and pins 2 i. The panel is provided with attaching openings 23 for securing the apparatus to the instrument panel of aircraft or in any other locality within convenient reach of the pilot.

A plurality of cylindrical recording plungers 2t equal in number to the number of spring pressed locking discs Il, are slidably mounted in annular recesses formed radially 'ln the plunger housing i9. A helical spring 26 is sleeved on each plunger and is confined under tension in an enlarged cylindrical recess 21 one end of the spring bearing against the inner wall of the recess and the outer end 'of the 'spring bearing against a button 28 which is screw threaded onto the plunger. The spring tends constantly to hold the plunger at its outer limit of movement.

Each plunger is equipped with a hawk bill 29,

having a base portion of substantially rectangular f vment with the ange I1 of the respective locking disc. one of the plungers is set by the pilot in locking engagement with its respective locking disc no other plungerfmay thereafter be set since the discs Il have only play enough to admit one plunger to be interleaved between the discs at which time the discs are jammed against each other and against the cap nut I3 and rigid washer Consequently one, and only one selected plunger can ever be moved to locking or recording position.

By referring to'Figure 1 itiwill be noted that legends are disposed laterally of respective ones of the plungers, such legends indicating approximate causes of crashes, such as motor failure, gas leaks, flre breaking out, lost by instrument failure or the like, and control collapse. legends are merely given by way of example as any desired legends may be used and any number of plungers and the corresponding number of locking discs may be employed as desired. All of the parts are preferably formed of metal so as to be as nearly as possible indestructible and the legends'are applied to the panel 20 in any suitable manner so as to be easily readable in emergencies by a pilot, and to retain as much as possible their legibility after being recovered from wreckage.

As a precaution against tampering, and also to protect the plungers from destruction by contact with wreckage, a shield 34 is mounted to rotate about the axis of the cylinder i0 to a position shown by dotted lines in Figure 3 in which the plunger buttons 28y are embraced by the shield and usually the pilot is supposed to swing this shield to operative position instantly after depressing his selected plunger to record the cause of a crash which is imminent, unavoidable, and certain to happen. p

For rotatably mounting the shield on the cylinder a pair of bearing rings 35 are rotatably mounted on shoulders 36 formed on the cap nuts l2 and I3 and arcuate supporting arms 31 are riveted to the rings as shown at 38 or otherwise secured in place. The arcuate arms are bridged by a bar 39 which is integral with the shield 34, as best shown in Figure 3, and is provided with housings 40 in which helical springs 4i are disposed. These 1 helical springs 4i bear upon one flange of a channeled latch member 42 which is slidably mounted on the underneath face of the bar` 39, and hold saidflange in frictional' engagement with the cylindrical wall of the cylinder I0. During rota- As best shown in Figure 2, when any` These tion of the shield on its axis to a positionto embrace and protect the plungers, the springs 4I will force said flange of the latch into a latching groove 43 formed longitudinally in the wall of the cylinder so that the shield is yieldably held in its operative position and cannot be removed from operative position until the mating flangev 44 `of the latch is manually pulled outwardly to release the latching flange from the latching groove.

In operation the apparatus may be mounted on any suitable part of the aircraft within convenient reach of a pilot. The shield 34 is normally rocked to released position to expose the plunger buttons 28, in which position inturned stop ngers 45, best shown in Figure 4, on the arcuate arms 31, are in position to engage the rear face of the panel 22 and prevent swinging of the shield out of convenient reach of the pilot. In the event of an accident involving any failures such as are indicated by the legends on the panel 22, at the moment.

the pilot decides that a crash is imminent, un'- avoidable, and certain to happen, he may record the defect by quickly pushing in the corresponding plunger and then instantlyrotating the shield 24 into position over the row of plungers. As previously explained, the selected plunger will interlock with its respective locking disc and cannot be dislodged until authorized persons, investigating the cause of the crash, remove the sealed cap nuts lI2 and i3 to permit the spring i5 to release the locking discs. 'I'hus investigators seeking the cause of a crash may have a clue, recoverable from the wreckage, as to the cause of the crash, as pointed out by the pilot, and thus have an opportunity to correct faulty aircraft construction and prevent future loss of life and property in future aircraft construction as well as current aircraft in daily use.

From the above description it is thought that the construction and operation of the invention will befully understood without further explanation.

What is claimed is:

1. A crash cause recorder for aircraft comprising a supporting cylinder, means for securing the cylinder to aircraft' within convenient reach of a pilot, spring pressed recording plungers, distinctive legends associated with respective plungers designating probablecauses of a crash, and a plurality of locking discs carried by the cylinder and corresponding to respective plungers, the discs being so shaped and arranged that when a selected plunger is set in locking engagement with its respective disc by a pilot it will be impossible to release the set plunger ers adapted to be selectively operated by a pilot when a crash is imminent, unavoidable, and certain to happen, distinctive legends associated with respective plungers designating probable causes of a crash, a plurality of locking discs carried by the cylinder and engageable by and in alignment with respective recording plungers, and a spring controlling the discs to permit sufllcient play between the discs to admit only the one selected plunger to be interleaved be'- tweenvthe discs'when a selected plunger is set by the pilot in locking engagement with its respective disc and prevent setting of any of the remaining plungers.

3. A crash cause recorder for aircraft ccmprislng a supporting cylinder, cap nuts closing the ends of the cylinder, means for securing the cylinder to the aircraft within convenient reach of a pilot, a plunger housing extending longitudinally of one side of the cylinder, plungers carried by the housing and adapted to project into the cylinder, a plurality of locking discs nested in the cylinder between the cap nuts, and a compression spring in the cylinder urging the discs endwise, each disc having a locking flange and each plunger having a hawk bill extremity engageable with said ange, said hawl; bill being beveled to provide cam faces adapted to enter between and move apart two adjoining discs whereby the hawk bill of a' selected set plunger will lockingly engage the ange of a respective locking disc, said spring permitting predetermined play between the discs so that when a selected plunger is set by the pilot in locking engagement with its respective disc it lected plunger.

will be impossible to release the set plunger or to operate any of the remaining plungers.

4. A crash cause recorder for aircraft cornprising a supporting cylinder, means for securing the cylinder to aircraft'within convenient reach of a pilot, a plurality of recording plungers arranged on one side` of the cylinder and projecting into the cylinder, locking discs in the cylinder adapted to be selectively engaged by respective plungers when a predetermined plunger is set by a pilot, legends associated with the plungers designating probable causes of a crash, a shield mounted for rotation on the axis of the cylinder and adapted to embrace said plungers and protect the plungers from injury by contact with wreckage, and means for releasably locking the shield to the cylinder, said shield being adapted to be rotated to embrace the plungers by the pilot after setting of a se- SIDNEY G. ALLEN.