Closed loops and shared mental models

Two people can only fly the same plan if each hears the other close the loop — say it, read it back, confirm it.

The idea

A crew shares a job only if they share the same picture of it. The picture stays shared through a small ritual: one person gives a command, the other gives a readback, and the first confirms with a . Callouts, briefings, and an explicit transfer of controls do the same work.

Skip the loop — a mumbled “roger,” a silent knob turn, an ambiguous “you’ve got it” — and the two pictures quietly drift apart. Nobody notices, because divergence is silent. It only announces itself at the worst moment: when the two of you act on different plans.

watch the two pictures stay together, or drift

Captain pilot flying

heading 270°
flying Captain
approach briefed not yet

in sync

First officer pilot monitoring

heading 270°
flying Captain
approach briefed not yet

divergence

Communicate by:

start — both pictures match

divergence

Press step to run the descent. Try it once on closed loop, then reset and run it on bare minimum — and watch the pictures come apart.

How it works

Closed-loop communication is three moves, every time information changes hands:

command    "Descend and maintain three thousand."      (sender states it)
readback   "Down to three thousand."                    (receiver repeats it)
hearback   "That's correct."  /  "Negative — TWO thousand." (sender verifies)

The readback is the receiver saying what LANDED in their picture.
The hearback is the sender checking it matches the picture they SENT.
A mistake shows up in the gap between them — and gets caught out loud.

Skip a move and the loop is open:
   "roger"            -> no readback, so a mishear is never surfaced
   silent knob turn   -> no callout, so the monitor's picture goes stale
   "you've got it?"   -> no confirmed transfer, so each may think
                        the OTHER is flying -> nobody is

Briefings sync the plan before it’s needed; standard callouts sync each change as it happens; explicit transfer of controls (“you have the aircraft” — “I have the aircraft” — “you have the aircraft”) syncs who is responsible. All of them are the same idea: don’t assume the picture is shared — close the loop and confirm it.

When to use it

Close the loop whenever…	The trade-off / limit
Information changes hands and someone will act on it (a clearance, a hand-off, a dosage, a deploy command).	It costs a few seconds of talking — cheap next to acting on a wrong shared picture.
Roles or responsibility move between people (transfer of controls, on-call handover).	Ritual can feel stiff; do it anyway on the items that matter, not every word.
The environment is noisy, rushed, or fatigued — exactly when mishears happen.	Under pressure people compress to “roger” — that’s the moment the readback earns its keep.

Watch out for

“Roger” as a readback. “Roger” means “I heard you,” not “here is what I heard.” It can’t catch a mishear because it never repeats the content.
Silent changes. Turning a knob or resetting a value without a callout leaves the other person’s picture . Say what you did.
Ambiguous transfer of controls. “You’ve got it” without the three-way confirmation is how both pilots end up thinking the other is flying.
Expectation bias in the hearback. You hear the number you expected, not the one that was said. The readback only works if the sender actually listens to it.
Assuming a shared brief. “We both know the plan” is an assumption, not a confirmation. Brief it out loud, once.

Worked example

An interviewer asks about a time miscommunication nearly caused a problem, or how you keep a team aligned. A strong answer names the mechanism, not just “we communicate well.” In the sim above: ATC says descend to 3,000, then amends to 2,000. On closed loop, each readback puts both pilots at the same number, and the amendment re-syncs them — even a late loop catches an earlier drift. On bare minimum, two “rogers” leave the Captain at 2,000 and the FO still believing 5,000; mid-descent, that gap is a setup for leveling at the wrong altitude — and the ambiguous hand-off leaves no one sure who’s flying. The lesson transfers straight to an on-call handover or a deploy: state it, have it read back, confirm it.

Check yourself

ATC clears you to 4,000. Your first officer, running checklists, replies “roger.” What’s missing?

You hand over flying with “okay, you’ve got it” and go heads-down on a chart. What’s the risk?