Minimum Autopilot Disconnection Heights – CAT I vs CAT II

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Topic: Minimum Autopilot Disconnection Heights – CAT I vs CAT II

"Welcome back to the A320 Mentor Channel — the place where Airbus knowledge turns into pilot confidence. Today, we’re diving into a subtle, but crucial part of Airbus flying: minimum autopilot disconnection heights. CAT I, CAT II, CAT III — when exactly do you need to take over? And what happens if you don’t follow the rules? Stick with me, because this is one of those topics where the FMA tells you more than the chart ever will."

CAT I — 160 ft AGL

 *"Let’s start with CAT I. On a CAT I approach, with the FMA showing CAT 1, the rule is clear: the autopilot must be disconnected no lower than 160 feet above the ground.

Now — here’s the catch. If you disconnect later, say at 100 feet or even at flare height, the airplane won’t suddenly misbehave. Technically, it’ll keep flying perfectly fine. But… and this is important… you’d be operating outside certification and FCOM limitations.

In the event of an audit or an incident, this would be considered non-compliant. The autopilot in CAT I mode simply isn’t certified for coupled flight below 160 feet. So yes, the autopilot may work — but you, as the pilot in command, would carry the full responsibility for violating minima."*

CAT II — 80 ft AGL

*"Now, let’s move to CAT II. On a CAT II automatic approach, without autoland, the autopilot must be disconnected no lower than 80 feet AGL.

Again, if you keep it in longer, the airplane won’t scream at you or disconnect by itself. But you’d be outside system certification. CAT II is only approved to hand over to the pilot at or above 80 feet. Below that, if you disconnect, you’re flying in a zone the system wasn’t designed or certified to support.

And here’s the reality: if something goes wrong, it’s officially a pilot deviation, because you didn’t comply with the published minima."*

Why These Restrictions Exist

 *"So why 160 feet for CAT I, and 80 feet for CAT II? These aren’t mechanical cutoffs. The autopilot doesn’t suddenly disconnect at those altitudes.

Instead, these are certification and safety boundaries. CAT I autopilot mode hasn’t been tested or approved to flare below 160 feet. CAT II, without autoland, is tested and certified down to 80 feet — but no further.

Airbus, EASA, and the FAA draw these lines to guarantee redundancy, system reliability, and safe pilot readiness for takeover. It’s about protecting you and your passengers, not about what the airplane can technically do."*

Myth vs Fact — Clearing Misconceptions

"Now let’s bust a few myths, because I know you’ve heard these before.

Myth #1: “The autopilot will drop out automatically if you pass 160 feet on a CAT I approach.”
Fact: Not true. The autopilot will happily keep flying below 160 feet. It doesn’t suddenly quit. But — it’s not certified to do so. If you let it, you’re outside the approved envelope.

Myth #2: “If I disconnect the autopilot below 80 feet on a CAT II approach, it’s fine — the airplane can handle it.”
Fact: The airplane won’t complain, but certification only allows autopilot down to 80 feet. Below that, you’re in uncharted territory, and in the event of an incident, it falls on the pilot, not the system.

"So here’s the reality check: the autopilot doesn’t just ‘quit’ at 160 feet on CAT I or 80 feet on CAT II. These are legal and certification limits, not technical ones. Respect them, because safe flying isn’t about what the airplane can do… it’s about what the airplane is approved to do."

Closing

 *"And that’s the key lesson, mentors: your FMA is your truth. Read it. Respect the minima. Stay inside the certified envelope.

If you enjoyed this breakdown, subscribe now to the A320 Mentor Channel, give this video a thumbs up, and share it with your fellow Airbus pilots. Remember: fly smart, land safe… and always mentor the next generation."*


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