> failsafe timers and dead-man switches when testing new things. Aircraft and spacecraft are more than anything, mass constrained. Such failsafes are welcome i

> failsafe timers and dead-man switches when testing new things. Aircraft and spacecraft are more than anything, mass constrained. Such failsafes are welcome in software, but neither the bleeding-edge engineers not even the test pilots would support adding failsafe mass if it would affect the tests.