You're two days into a sprint. A customer reports the integration you shipped last week is breaking their workflow. The Scrum Guide says the backlog is frozen. Reality says you're fixing it. So you do - quietly, and pretend the plan never changed.
This is how most teams handle scope changes - not with a process, but with a fiction.
The sprint backlog is sacred - and other myths
The Scrum Guide is clear: the sprint backlog is locked once planning is done. In practice, this rule is broken so routinely it barely qualifies as a guideline. Production bugs appear. The CEO walks into standup with a "quick ask." Every team that has run Scrum knows this happens. Most don't talk about it.
The result is a gap between the official plan and actual work - and that gap erodes trust. Retrospectives become performances. Velocity metrics become meaningless.
Ground Mechanics: the first line of response
In Flights, the first answer to "can we handle this?" isn't to touch the flight at all. Ground Mechanics are team members who work between flights - handling bugs, urgent fixes, and requests that don't belong on the main flight plan. When something comes up mid-flight, Ground Mechanics absorbs it without disrupting the crew's focus or adding weight to the flight.
This is the fallback Scrum doesn't have. Instead of quietly amending a frozen backlog, you route the work to the right place.
When the flight itself needs to change
Sometimes the scope change is too big for Ground Mechanics - it belongs on the flight. In Flights, the captain owns that call. One person looks at the incoming request, looks at the remaining crates, and decides: does this go on the flight, or not?
When a crate is added or dropped, the whole crew sees it. The change is visible and deliberate - not a silent amendment. A fixed landing date keeps the stakes real: when the flight lands, you see exactly what got done.
The discipline isn't rigidity - it's honesty
A frozen backlog doesn't prevent scope changes - it just makes them invisible. Invisible changes cause the most damage because nobody accounts for them.
Flights takes a different position: scope changes are a feature of how real teams work, not a bug in your process. Ground Mechanics handles the day-to-day interruptions. The captain handles the bigger calls. Everything is visible to the crew and accounted for at landing.
If your team quietly changes the sprint backlog every cycle, you're already doing scope changes - just without visibility or ownership. You might as well make it official.
Read more about crates, Ground Mechanics, and what happens during a flight when the plan needs to change.