Mastering the "Unflyable": Navigating A320 Dual Hydraulic Failures via the QRH Summary
Welcome back to the Masterclass. Today, we are dissecting one of the most cognitively demanding scenarios you will ever face in the A320: the Dual Hydraulic Failure. On a normal day, the A320 is a masterpiece of automation—a "fly-by-wire" cocoon that makes life easy. But when two hydraulic systems go dark, that cocoon is stripped away. You are left with a significantly degraded aircraft, a spiking workload, and a test of raw airmanship.
In the simulator, I see even the most seasoned crews struggle when the "magic" fades. Handling a failure of this magnitude requires more than just following lights; it requires a highly disciplined, strategic approach. This is exactly why Airbus developed the QRH Summaries. They aren't just checklists; they are your survival roadmap for bringing a wounded bird back to the numbers.
From Checklists to Strategy: The QRH Roadmap
While the Electronic Centralized Aircraft Monitor (ECAM) is excellent for handling immediate "drill" items, it is fundamentally insufficient for the long-term management of a dual hydraulic failure. The ECAM provides the "what," but it cannot seamlessly manage the chronological flow of the flight. As Airbus puts it:
"The ECAM alone cannot seamlessly manage the chronological flow [of the remainder of the flight]."
The QRH Summary fills this gap by providing a strategic roadmap divided into four chronological phases: CRUISE, APPROACH, LANDING, and GO-AROUND.
In the CRUISE phase, the summary forces you to move beyond the immediate failure. You must assess remaining systems and flight capabilities to select an appropriate diversion airport, while simultaneously calculating increased fuel consumption and landing performance—critical data points often overlooked in the heat of the moment. As you transition to the APPROACH phase, the summary acts as an integrator, weaving independent procedures like "LANDING WITH SLATS OR FLAPS JAMMED" and "L/G GRAVITY EXTENSION" into a single, cohesive plan.
The Discipline of Sequence: Respecting the STATUS Page
In my experience as an instructor, the most common "gotcha" is the "premature jump." When the master caution rings and the screen turns amber and red, the natural instinct is to grab the paper QRH immediately. Resist that urge. Rushing to the summary before finishing the ECAM is a recipe for disaster.
You must respect the workflow: Finish all ECAM actions, move through the STATUS page—which acts as the vital bridge between automated clearing and manual management—and only when the Pilot Monitoring (PM) announces "ECAM ACTIONS COMPLETE" do you transition to the QRH summary. If you skip ahead, you risk missing immediate, automated system reconfigurations that are vital to the aircraft’s current state. Crosscheck the ECAM STATUS page at every single step of the summary.
Rediscovering the Stick: Handling Alternate and Direct Law
When you lose two hydraulic systems (such as Green + Blue or Green + Yellow), the Autopilot (AP) is gone. Period. The Pilot Flying (PF) is now hand-flying an aircraft in Alternate Law.
Here is the "PF Trap": I often see the PF get sucked into the ECAM or the QRH paperwork, trying to help the PM diagnose the failure. Don't do it. If you are the PF, you must ignore the paperwork entirely. Your cognitive capacity must be 100% dedicated to the flight path. Maneuver with extreme care; remember, you are operating on only one remaining hydraulic system. High-demand control inputs could further degrade your remaining flight control authority.
Furthermore, you must anticipate the "hook" at the end of the approach: the moment you extend the landing gear, the aircraft reverts to Direct Law. This shift in handling characteristics, combined with the high workload of an abnormal configuration, is where the flight path is most at risk. Fly, navigate, and communicate—in that strict order.
The "Mayday" Mandate: Transparency in Crisis
A dual hydraulic failure is not a "Pan-Pan" situation. It generates a red LAND ASAP message on the ECAM, signifying a time-critical emergency. I sometimes see crews downplay the situation to ATC, perhaps out of a desire to remain "cool" on the radio.
This is a professional error. You must declare a MAYDAY. Total transparency is a survival requirement. ATC needs to know that you are in a significantly degraded state with limited maneuverability. Declaring an emergency ensures you get priority handling and that emergency services are standing by for an aircraft that may have limited braking or steering capability once on the ground.
The Meticulous Arrival: Briefing for the Degraded State
Because you are hand-flying in a degraded law with abnormal configurations, a standard briefing won't cut it. The QRH summary provides the exact structure you need to ensure no critical detail is missed.
Your briefing must be meticulous and cover:
- L/G Gravity Extension: The manual process and timing for dropping the gear.
- Selected Speeds: The transition from managed guidance to manual speed control.
- Abnormal Configuration: How the jammed slats or flaps will affect your approach profile.
- Tail Strike Awareness: The increased pitch attitudes required in certain degraded states.
- The Go-Around: This is the most critical part. You must brief the exact go-around configuration and speed, as a standard "Go-Around, Flaps" call may not apply to your specific failure.
Conclusion: Beyond the Chocks
The QRH summary is your primary tool for bringing a severely crippled aircraft safely back to the chocks. It moves you from reactive troubleshooting to proactive management. When the systems fail and the cockpit becomes a high-pressure environment, trust the structure of the procedure to guide your judgment.
Reflect on Golden Rule 4: Take action if things do not go as expected. In a dual hydraulic failure, things have already gone wrong. The question is: do you have the discipline to follow the roadmap, or will you let the workload fly the airplane for you?
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