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Expected Forces Acting on Avionics Tower

Over the course of the Hermes III flight we expect the Avionics Tower (referred to simply as AV tower from here on) to be acted upon by moderately large forces from various different sources which have been outlined below. Further included is a approximate calculation of there magnitude based upon historical launch data and the tower's characteristics and direction of the forces' action on the AV tower.

1. Motor Thrust Force
   Using Hermes II statistics we know that maximal thrust provided by the motor is approximately 3000 lbs. of thrust. Which directly means that at any point in time the AV tower must be able to withstand upwards of 3000 lbs of force onto the faces of its end caps. In order to deal possible error we will consider a 25% safety factor and only fly the part if it can withstand up to 3750 130 lbs of force (approximately 600 Newtons). It should be furthermore noted that this force for testing must be equally spread across the surface of the end cap.
2. Separation Shock
   Again using Hermes II statistics...(add edits here)
3. Impact Force
   Following apogee the Hermes III will fall eventually impacting the ground at approximately 30 m/s using energy methods we can use this to approximate the total energy of the AV tower the instant prior to impact. However this is not specifically needed assuming we can find terrain that is roughly similar in ground elasticity to the Death Valley Desert floor. This can be approximated using grass. So calculated the approximate force is needless.

Testing Procedures for Avionics Tower

Testing for Motor Thrust and Separation Shock

As both of these forces are approximately uniform across the area of the endcaps of the AV tower we can test the failure point as well as flight readiness of the part using simplistic methods. By attaching weights of equal mass (six in number one for each panel) we can approximate a uniform load distribution across the surface of the AV tower endcap so long as the total weight is equal to the maximum motor thrust or separation shock for whichever is greater.

Testing for Impact Force

As partially described above, we can test the impact force aptitude of the AV tower by dropping it from an altitude predetermined using simple kinematic equations that at impact the AV tower has an approximate velocity of 40 m/s. By doing this we can presume that in this case grass has a extremely similar ground elasticity to the desert floor at the launch site. Due to this fact the forces that would be acting on the AV tower should be approximately equal.