How to handle a roll trim runaway in the SkyWest ERJ cockpit: press and hold the AP/TRIM Disc button

Roll Trim Runaway in the ERJ: The One Move That Really Counts

Let me explain something that all Skywest ERJ pilots drill into their bones: when roll trim goes rogue, time and control are of the essence. The jet might start yawing or banking with no clear command from the stick, and the autopilot can complicate things if it’s still engaged. In that high-stakes moment, the memory item you reach for—AP/TRIM Disc button press and hold—is not just a checkbox. It’s the first, critical step toward regaining hands-on control.

What a roll trim runaway actually feels like

First, a quick mental picture. You’ve got the autopilot either engaged or playing in the background, and the aircraft begins to roll in an uncommanded way. It might start leaning toward one wing with an unexpected trim input adding to the motion. The natural impulse is to flinch, grab the controls, and try to steady the airplane with quick, reactive corrections. But here’s the catch: if the trim system is running away, you don’t want to chase the problem with more trim or a hurried manual input. You want to separate the autopilot and the trim system from the equation so you can take clean, deliberate control back.

The memory item that saves the day

The correct response is straightforward in theory and decisive in practice: AP/TRIM Disc button press and hold. What does that do, exactly? It disconnects the autopilot and the roll trim system. In one deliberate action, you stop the trim runaway from keeping the aircraft in an unsafe rhythm and you reclaim manual control. It’s a memory item because it’s a crisp, repeatable step that you execute under stress, not something you improvise on the fly.

Think of it like flipping a switch that cuts the autopilot and trims away from the cockpit’s automatic nudges. Suddenly, you’re flying the airplane again with your hands on the wheel, your eyes on the horizon, and your mental map returning to a stable baseline. When the airplane is out of balance due to runaway trim, the safest path forward is to stop the automatic tendencies as quickly as possible and assess your options with a clean slate.

How to respond in the cockpit: a practical sequence

Here’s a grounded way to think about it, without turning it into theater:

1. Recognize the anomaly

• The aircraft begins to roll with a rhythm that doesn’t match your inputs.

• The autopilot may still be connected, or you might notice unusual trim activity that doesn’t settle with your adjustments.

2. Pin down the action to take

• Remember the memory item: AP/TRIM Disc button press and hold.

• This action is designed to yank the autopilot and roll trim off-line so you can pilot manually.

3. Execute the memory item with purpose

• Locate the AP/TRIM Disc switch on the captain’s side (typical ERJ layouts place it within easy reach on the glareshield).

• Press and hold the AP/TRIM Disc button. Do not release it until you’ve stabilized the situation.

• You’re not “fixing” the problem with more inputs; you’re stopping the automatic system so you can take control.

4. Reassess and reestablish control

• With the autopilot and roll trim disconnected, bring the aircraft to a stable, coordinated flight.

• Use gentle, deliberate control inputs to keep wings level and maintain a comfortable bank and pitch.

• Once you feel you have the aircraft under manual control again, consider whether to hand-trim carefully or re-enable trim in a controlled, deliberate way.

5. Decide the next steps after stabilization

• If the runaway is successfully contained, continue the flight with manual control and follow the company SOPs for further checks.

• If the situation persists or you can't regain stable control, follow the immediate escalation procedures and prepare for any required contingencies with the appropriate crew and air traffic control.

Why this answer makes sense compared to other options

In a moment of confusion, it’s tempting to grab at the closest physical cue—like the wheel or a visible trim indicator—and try to muscle through the problem. Some questions might pop up in your head about “the wheel jam” or “aileron trim fail.” The point is this: those options don’t rapidly disconnect the autopilot and the roll trim system, which is the essence of breaking the runaway’s grip. The AP/TRIM Disc action is the fastest, cleanest way to halt the runaway forces and regain clean control. It’s not about overpowering the issue with a stronger input; it’s about removing the automatic influence so you can reestablish control safely.

Why this matters beyond a multiple-choice question

This memory item isn’t a trivia nugget tucked away in a book. It’s a real-world tool that keeps you and passengers safe in turbulent moments. In the Skywest ERJ cockpit, the emphasis on quick, reliable responses mirrors how crews operate under pressure in the airspace you’ll actually fly through. It’s one thing to know the right answer in a test; it’s another to live the decision under cockpit lighting, weather, and cabin pressure. Having this action ready—publicly documented, practiced, and translated into muscle memory—reduces reaction time and clarifies priorities when the instrument panel looks chaotic.

A note on the broader CQ and KV landscape

Within Skywest CQ and KV knowledge areas, the emphasis isn’t just on memorizing commands. It’s about internalizing why those commands exist and how they influence the airplane’s behavior. The roll trim runaway scenario is a perfect example: you learn not only the exact memory item but also the rationale—disconnecting the autopilot and trim so you can fly manually, stabilize, and then proceed with the flight in a controlled, deliberate manner. That kind of understanding matters because it helps you explain decisions clearly to instructors, peers, and maintenance crews if you ever need to debrief.

Common misconceptions worth clearing up

• The first instinct to jam the controls is not the fix. Strong, reactive input can worsen a trim-driven roll if the autopilot is still trying to hold path or if trim inputs are fighting you.

• A “jamming” wheel is not the quick fix you want in this scenario. While it may reflect a symptom, it doesn’t address the root problem—the need to stop the autopilot and trim system from applying uncommanded inputs.

• Relying on a single mechanical failure scenario (e.g., aileron trim fail) without acknowledging the autopilot’s potential involvement can delay the correct, fast action.

A few practical tips from the cockpit floor

• Build it into muscle: regularly rehearse the AP/TRIM Disc action in your training mindset. The more automatic it becomes, the quicker you can react when it counts.

• Keep it simple: in the lead-up to a flight, one quick, repeated mental check is better than a maze of second-guessing when you’re dealing with a roll disturbance.

• Trust the sequence: your primary goal is to regain control. After that, you can evaluate configurations, rerun checks, and coordinate with air traffic control if needed.

Closing thought: stay calm, act decisively

Roll trim runaway is the kind of scenario that tests both skill and nerve. The memory item AP/TRIM Disc button press and hold is crafted for exactly that moment: a clean break from automatic systems so you can steer the airplane safely again. In the end, it’s a small action with a big payoff—one that underscores the core philosophy of flight safety: clarity, control, and composure under pressure.

If you’re delving into Skywest CQ and KV topics, you’ll notice the same thread again and again—clear procedures, repeatable actions, and a deep understanding of why those actions matter. The memory item for roll trim runaway isn’t just a line on a checklist; it’s a cornerstone of safe, capable flying in the ERJ fleet. And that, more than anything, is what separates good pilots from the ones who stay on course when the skies get a little unruly.