Applying a mindset of identifying, evaluating, and mitigating risks can show up in a number of ways.
Sometimes it’s in the physical safety measures included: one aircraft I’ve worked on has a rectangular plug in the middle of each of its two booms. When inserted properly, these plugs arm the vertical takeoff and landing (VTOL) system. They complete the electrical circuit and allow power to flow from batteries to the motors and propellers.
Whenever someone is working around the aircraft, those plugs are inserted upside-down so there is no electrical connection. The propellers physically cannot spin on their own.
And during flight operations, the absolute last step the ground crew does with the aircraft is to flip and re-insert those plugs to arm the electric motors. After this, everyone stays well away from the plane.
The tops of the plugs are even painted bright red to get the message across: these props are powered and could spin at any time.
Maybe this sounds like a pretty obvious safety measure to implement. You’d probably want to control whether or not your very-fast-spinning things can actually spin.
But to end up in the final product, it still required thought and care. Sometimes it’s the most “obvious” things that get missed—or worse, noticed but ignored.
Safety in engineering can also show up in your component selection. To start the main engine, this same aircraft required a “kick” to its propeller. A crew member takes an impact drill with a long skinny tube welded to it, nests a pin at the end of the tube into a slot in the propeller hub, and gives it a spin, similar to how aircraft from World War I were started. This tube is pretty darn long to keep the crew member well out of the way. But it’s not exactly the best setup.
A newer engine control unit (ECU) replaced that whole process with remote start capability. With the push of a button, the engine turns over all on its own. No one needs to kneel behind the aircraft to spin the prop.
Choosing to use this ECU removed one of the biggest hazards to operators, making this aircraft even safer than it was before. (And added some flair—having seen the remote start in action, it is impressive to experience.)
We take so many factors into account during engineering projects: time, budget, weight, ease of manufacture, etc.
But one to add to that list is safety. How can you reduce the risk to your vehicle’s operators and maintainers? Do you need to implement physical safety features? Can you pick components that will themselves mitigate hazards?
You can never entirely remove risk. But you can prioritize the safety of everyone involved from the get-go.