Possible Clues:

• Female easily carried instrument in black box
• Fine delicate instrument in black box
• Schoolchild's instrument put under stairs in black box?
• Musical instrument underneath stairs in black box
• Black box in an aeroplane
• Series of steps by judge that provides key to cause of accident?
• Loud instrument's easily carried inside black box
• Holder of evidence about crash given fine, not heavy, by judge
• Aircraft installation
• One revealing cause of crash given fine (not heavy) by judge