On the other hand, the local auto mechanic probably has a dozen wrenches and a parts truck that comes around every other day that can bring a new one in for nearly zero overhead. So she might be willing to accept a higher failure rate.
Using male gendered pronouns for overwhelmingly male-dominated professions isn't sexism. If you threw a rock into a crowd, you'd hit more male teachers than female mechanics. It's okay to assume a mechanic is a "he" and a teacher is a "she".
Or, alternately, go whole hog. Instead of someone working in aerospace or other sensitive area, say a woman working in aerospace or other sensitive area.
Your last paragraph suggests that your pronoun gendering may have been intentional and part of a larger issue you wished to promote. If so, bravo! I award you one Internet point for being aggressively subtle.