Shock tests are performed to assure that materiel can withstand the relatively infrequent, non-repetitive shocks or transient vibrations encountered in handling, transportation, and service environments. Shock tests are also used to measure an item's fragility, so that packaging may be designed to protect it, if necessary. Mechanical shocks will excite an equipment item to respond at both forced an natural frequencies. This response, among other things, can cause:

1. Failures due to increased or decreased friction, or interference between parts.

2. Changes in dielectric strength, loss of insulation resistance, variations in magnetic and electrostatic field strength.

3. Permanent deformation due to overstress.

4. More rapid fatiguing of materials.

The TDS Recon is tested in accordance with Procedure IV, Transit Drop, for items weighing less than 45.4 kg (100 lbs.), and under 91 cm (36 in.) in its largest dimension. Test items are dropped on each face, edge and corner, for a total of 26 drops, from a height of 122 cm (4 ft.).