alt Hacker NewsFor a sub-minute flight the drift budget is actually pretty forgiving — a MEMS gyro drifts maybe 1-3 deg/sec, and if you're fusing with accelerometer data you really just need "which way is up" and "am I still pointed at the target." A $5 IMU can hold that for tens of seconds.
Where you're right is repeatability. Mil-spec works the same on launch 1 and launch 500 across temperature extremes. Consumer MEMS you'd need to characterize each unit individually — fine for a demo, impractical at any scale.
Hm. Is it, though? If what you wanted to do was produce a large batch of calibrated IMUs, building a rig to do so wouldn't be an enormous undertaking.
Or do you mean to characterise the assembled vehicle?