Some thoughts
As an Electronics engineer although not involved in Aviation I have a few thoughts.
1) In order to retrofit at acceptable cost a plug and fitment compatible unit would be the favorite starting point.
2) weight saving might be used as an offset to the cost.
3)The storage would need to be unaffected by water and pressure.
4)Redundancy within the unit could be used to offset the possibility of damage to one storage device.
5)The lifetime of the sonar transmitter would ideally be extended possibly by use of a sonar receiver to trigger additional transmission.
PS. I have read that a larger capacity crash survivable memory unit may be readily available. It seems that this could be an immediately available improvement.
Last edited by Rory166; 21st Mar 2014 at 21:19.
Reason: New Info.