I just emailed a request to the Tripoli board, via Steve Shannon, that independent, magnetically-activated, solid state electronic switches like those sold by Featherweight Altimeters be considered equivalent to mechanical switches in the Tripoli safety code.
Keeping the power switch independent from the downstream electronics is important. You don't want a single failure to be able to turn on the switch and make the altimeter inadvertently activate a charge. The Featherweight magnetic switches are completely independent of whatever it is that is connected to its output, just like a mechanical switch or a battery disconnect is.
Reliability is also important, both to prevent an accidental turn on, and just as importantly, to prevent an accidental turn-off that could keep a chute from coming out. Featherweight magnetic switches have proven to have excellent reliability over more than a decade, with more than 1000 units in the field, used by hundreds of fliers. Rocketry has only anecdotal evidence, but there haven't been reported problems with magnetic switches like there have been with mechanical Schurter switches, for example. In other industries that have collected hard evidence, it's no contest, solid state switches have proven to be vastly more reliable than mechanical switches.
I applaud Steve and the rest of the Tripoli Board's focus on safety, and for continuously working to improve it. Good policy is based on evidence, and I expect the Tripoli board to weigh the evidence appropriately when it comes to interpreting or clarifying the new rule that affects all of our safety.
Keeping the power switch independent from the downstream electronics is important. You don't want a single failure to be able to turn on the switch and make the altimeter inadvertently activate a charge. The Featherweight magnetic switches are completely independent of whatever it is that is connected to its output, just like a mechanical switch or a battery disconnect is.
Reliability is also important, both to prevent an accidental turn on, and just as importantly, to prevent an accidental turn-off that could keep a chute from coming out. Featherweight magnetic switches have proven to have excellent reliability over more than a decade, with more than 1000 units in the field, used by hundreds of fliers. Rocketry has only anecdotal evidence, but there haven't been reported problems with magnetic switches like there have been with mechanical Schurter switches, for example. In other industries that have collected hard evidence, it's no contest, solid state switches have proven to be vastly more reliable than mechanical switches.
I applaud Steve and the rest of the Tripoli Board's focus on safety, and for continuously working to improve it. Good policy is based on evidence, and I expect the Tripoli board to weigh the evidence appropriately when it comes to interpreting or clarifying the new rule that affects all of our safety.