Flight vehicles including scribed frangible seals and methods for the manufacture thereof

Abstract

Embodiments of a flight vehicle including a scribed frangible seal are provided, as are embodiments of a scribed frangible seal and a method for equipping a flight vehicle with a scribed frangible seal. In one embodiment, the flight vehicle includes a vehicle body having a deployment opening therein, and a deployable element residing in a stowed position within the vehicle body and movable into a deployed position. At least a potion of the deployable element passes through the deployment opening when moving from the stowed position into the deployed position. The flight vehicle further includes a scribed frangible seal, which is sealingly disposed over the deployment opening and which is positioned so as to be contacted by the deployable element during deployment thereof. The scribed frangible seal fractures along at least one scribe line when contacted by the deployable element to permit movement of the deployable element from the stowed position to the deployed position.

What is claimed is: 
     
         1 . A flight vehicle, comprising:
 a vehicle body having a deployment opening therein;   a deployable element residing in a stowed position within the vehicle body and movable into a deployed position, at least a portion of the deployable element passing through the deployment opening when moving from the stowed position into the deployed position; and   a scribed frangible seal sealingly disposed over the deployment opening and positioned so as to be contacted by the deployable element during deployment thereof, the scribed frangible seal fracturing along at least one scribe line when contacted by the deployable element to permit movement of the deployable element from the stowed position to the deployed position.   
     
     
         2 . A flight vehicle according to  claim 1  wherein the scribed frangible seal comprises a rigid substrate bonded to the vehicle body. 
     
     
         3 . A flight vehicle according to  claim 2  wherein the scribed frangible seal further comprises a plurality of scribe lines formed in at least one surface of the rigid substrate. 
     
     
         4 . A flight vehicle according to  claim 3  wherein the plurality of scribe lines comprises a plurality of scribe lines formed in an outer face of the rigid substrate substantially opposite the location at which the deployable element contacts the rigid substrate during deployment. 
     
     
         5 . A flight vehicle according to  claim 3  wherein the plurality of scribe lines extends in a substantially longitudinal direction from a forward portion of the rigid substrate to an aft portion thereof. 
     
     
         6 . A flight vehicle according to  claim 5  wherein the plurality of scribe lines comprises a plurality of substantially parallel scribe lines each extending in a direction substantially parallel with the longitudinal axis of the flight vehicle. 
     
     
         7 . A flight vehicle according to  claim 3  wherein the plurality of scribe lines comprises a plurality of laser scribe lines formed in an outer face of the rigid substrate. 
     
     
         8 . A flight vehicle according to  claim 7  wherein each of the plurality of laser scribe lines comprises a series of blind holes formed in the outer face of the rigid substrate. 
     
     
         9 . A flight vehicle according to  claim 7  wherein the rigid substrate is fabricated from a ceramic. 
     
     
         10 . A flight vehicle according to  claim 9  wherein the rigid substrate is fabricated from alumina. 
     
     
         11 . A flight vehicle according to  claim 3  further comprising a depression formed in the vehicle body and at least partially surrounding the deployment opening, at least a portion of the rigid substrate disposed within the depression. 
     
     
         12 . A flight vehicle according to  claim 11  wherein the depression is formed in an external surface of the vehicle body, and wherein the rigid substrate is matingly received within the depression in its substantial entirety. 
     
     
         13 . A flight vehicle according to  claim 11  further comprising a flexible edge bond joining at least a portion of the circumferential edge of the rigid substrate to at least one surface of the vehicle body defining the depression. 
     
     
         14 . A flight vehicle according to  claim 13  wherein the rigid body fractures into at least two longitudinally-extending pieces when contacted by the deployable during deployment thereof, and wherein the two longitudinally-extending pieces each rotate about the flexible edge bond to permit movement of the deployable element from the stowed position to the deployed position. 
     
     
         15 . A flight vehicle according to  claim 1  wherein the flight vehicle comprises a guided munition, wherein the vehicle body comprises a munition body, wherein the deployable element comprises a canard, and wherein the deployment opening comprises a canard slot. 
     
     
         16 . A scribed frangible seal for sealing a deployment opening through which a deployable element deploys, the scribed frangible seal comprising:
 a ceramic substrate; and   at least one laser scribe line formed in a surface of the ceramic substrate and imparting the ceramic substrate with a predetermined rupture strength, the ceramic substrate fracturing along the at least one laser scribe line during deployment of the deployable element.   
     
     
         17 . A scribed frangible seal according to  claim 16  wherein at least one laser scribe line comprises a plurality of laser scribe lines formed in a surface of the ceramic substrate, the plurality of laser scribe lines defining at least one longitudinally-extending fault line along which the ceramic substrate fractures when contacted by the deployable element during deployment thereof. 
     
     
         18 . A scribed frangible seal according to  claim 16  wherein the deployment opening is formed through a structure, and wherein the scribed frangible seal further comprises a flexible edge bond adhesively coupling a circumferential portion of the ceramic substrate to the structure. 
     
     
         19 . A method for equipping a flight vehicle with a scribed frangible seal, the flight vehicle including a vehicle body configured to house a deployable element when in a stowed position, the vehicle body having a deployment opening therein through which at least a portion of the deployable element passes when moving from the stowed position into a deployed position, the method comprising:
 obtaining a scribed frangible seal;   positioning the scribed frangible seal over the deployment opening in the vehicle body at a location at which the scribed frangible seal will be contacted by the deployable element during deployment thereof; and   bonding the scribed frangible seal to the vehicle body to seal the deployment opening.   
     
     
         20 . A method according to  claim 19  wherein the step of obtaining a scribed frangible seal comprises:
 laser-scribing a ceramic sheet to define a plurality of rigid substrates; 
 breaking the ceramic sheet to separate at least one rigid substrate from the plurality of rigid substrates; and 
 laser-scribing an outer face of the rigid substrate to yield the scribed frangible seal.