Crash survivable enclosure for flight recorder

A crash survivable enclosure for flight recorders for vehicles capable of operating over land and water, comprising:

• means including a plurality of spaced apart metal shells for enclosing and protecting a memory device against damage from (a) submergence in water at a substantial depth for a prolonged period of time, (b) fire and heat at a temperature of at least 1100.degree. C. enveloping 100% of the outside surface area of said shells for a minimum of 30 minutes, (c) impact shock of a magnitude of 1000 G's applied in each of the orthogonal axes for a time duration of at least 5 milliseconds, and (d) an external penetration impact force at least equal to that produced by a 500 lb. steel bar dropped from a height of 10 ft. to strike an outer one of said shells with a point of contact thereon having an area no greater than 0.05 square inches;
• and
• heat insulating filler means between said shells and between an inner one of said shells and said memory device for physically supporting said inner shell and solid state device in spaced apart physical and heat insulating relation;
• said filler means including a first filler for supporting said memory device within said inner shell and providing a heat sink for absorbing heat externally applied to said enclosure, and a second filler for supporting said inner shell inside an outer shell and having a low value of heat conductivity for minimizing heat transfer from said outer shell to said inner shell and contents therein;
• said first filler comprising a synthetic wax introduced into said inner shell around said memory device while in a liquid form and solidified therein to substantially fill said inner shell around said memory device for supporting the same within said inner shell.

A crash survivable enclosure for flight recorders for vehicles capable of operating over land and water, comprising:

• means including a plurality of spaced apart metal shells for enclosing and protecting a memory device against damage from (a) submergence in water at a substantial depth for a prolonged period of time, (b) fire and heat at a temperature of at least 1100.degree. C. enveloping 100% of the outside surface area of said shells for a minimum of 30 minutes, (c) impact shock of a magnitude of 1000 G's applied in each of the orthogonal axes for a time duration of at least 5 milliseconds, and (d) an external penetration impact force at least equal to that produced by a 500 lb. steel bar dropped from a height of 10 ft. to strike an outer one of said shells with a point of contact thereon having an area no greater than 0.05 square inches;
• said plurality of shells including an inner shell for containing and protecting said solid state memory device surrounded by a spaced apart outer shell for containing and protecting said inner shell and contents, said inner shell having at least one wall portion having a convex outer surface with an access opening formed therein;
• heat insulating filler means between said shells and between an inner one of said shells and said memory device for physically supporting said inner shell and solid state device in spaced apart physical and heat insulating relation;
• and
• a high pressure, sealed feed-through element mounted in said opening for sealing around electrical lines connected to said solid state memory device contained within said inner shell.

A crash survivable enclosure for flight recorders for vehicles capable of operating over land and water, comprising:

• means including a plurality of spaced apart metal shells for enclosing and protecting a memory device against damage from (a) submergence in water at a substantial depth for a prolonged period of time, (b) fire and heat at a temperature of at least 1100.degree. C. enveloping 100% of the outside surface area of said shells for a minimum of 30 minutes, (c) impact shock of a magnitude of 1000 G's applied in each of the orthongonal axes for a time duration of at least 5 milliseconds, and (d) an external penetration impact force at least equal to that produced by a 500 lb. steel bar dropped from a height of 10 ft. to strike an outer one of said shells with a point of contact thereon having an area no greater than 0.05 square inches;
• said inner shell comprising a hollow tubular body having an intermediate convex outer surface portion and opposite end portions in coaxial alignment with a central axis of said body tapering inwardly toward opposite outer ends;
• and
• heat insulating filler means between said shells and between an inner one of said shells and said memory device for physically supporting said inner shell and solid state device in spaced apart physical and heat insulating relation.

A crash survivable enclosure for flight recorders for aircraft, spacecraft and other vehicles operating over land and water, comprising:

• means including an inner shell for enclosing and protecting a memory device against the entry of water when submerged therein at a substantial depth for a prolonged period of time;
• first filler means for supporting said memory device within said inner shell, said first filler means comprising a wax-like material having a high melting temperature and a high value latent heat of fusion to act as a heat sink for absorbing a substantial quantity of heat, said wax-like material being introduced into said inner shell in a softened condition to substantially fill the space in said inner shall around said memory device and thereafter solidified to physically support said memory device within said shell;
• means including an outer shell for enclosing and protecting said inner shell and contents against substantial mechanical forces and fire;
• and
• second filler means for supporting said inner shell and contents thereof in said outer shell and protecting against fire, flame and heat.

A crash survivable enclosure for flight recorders for vehicles capable of operating over land and water, comprising:

• means including a plurality of spaced apart metal shells for enclosing and protecting a memory device against damage from (a) submergence in water at a substantial depth for a prolonged period of time, (b) fire and heat at a temperature of at least 1100.degree. C. enveloping 100% of the outside surface area of said shells for a minimum of 30 minutes, (c) impact shock of a magnitude of 1000 G's applied in each of the orthongonal axes for a time duration of at least 5 milliseconds, and (d) an external penetration impact force at least equal to that produced by a 500 lb. steel bar dropped from a height of 10 ft. to strike an outer one of said shells with a point of contact thereon having an area no greater than 0.05 square inches;
• heat insulating filler means between said shells and between an inner one of said shells and said memory device for physically supporting said inner shell and solid state device in spaced apart physical and heat insulating relation, said heat insulating filler means including a first filler for supporting said memory device within said inner shell and providing a heat sink for absorbing heat externally applied to said enclosure, and a second filler for supporting said inner shell inside an outer shell and having a low value of heat conductivity for minimizing heat transfer from said outer shell to said inner shell and contents therein;
• and wherein
• said first filler means comprises a synthetic wax introduced into said inner shell around said memory device while in a softened state and thereafter solidified therein to substantially fill said inner shell around said memory device for supporting the same within said inner shell.