Sep 09, 2025

What is a RAT

The Unsung Hero of the Sky: Understanding the Ram Air Turbine (RAT)

When people think of aircraft safety, their minds usually jump to ejection seats in fighter jets, oxygen masks in airliners, or redundant hydraulic systems. Yet, hidden within the sleek frames of both military and commercial aircraft lies a small but vital device: the Ram Air Turbine, or RAT. While it may never be as glamorous as a jet engine or as noticeable as a winglet, the RAT has saved lives and earned its place as one of aviation’s most ingenious emergency systems.

At Challenge Coin Nation, where we celebrate the culture and history of aviation through custom coins, patches, and morale gear, we know that even the smallest components often carry the biggest stories. The RAT is one of those stories.

We at Challenge Coin Nation are a veteran founded company and are honored to be able to continue serving our brothers and sisters in arms all over the world. We sell many different military themed items, but challenge coins are our specialty. Check out our accidental ejection coin below.

What Is a Ram Air Turbine (RAT)?

A Ram Air Turbine is a small, foldable propeller attached to a generator or hydraulic pump that deploys from an aircraft during emergency situations. Unlike the main engines or the auxiliary power unit (APU), the RAT doesn’t burn fuel or require a starter system. Instead, it harnesses the power of airflow as the aircraft moves through the sky.

Deployment: The RAT is normally stowed inside the fuselage or wing. In the event of dual engine failure or electrical loss, it automatically or manually deploys into the airstream.
Operation: Once exposed, the oncoming airflow spins the RAT’s blades. That spinning energy drives a hydraulic pump, generator, or both.
Purpose: The RAT powers critical flight controls, avionics, and essential systems long enough for pilots to stabilize and land the aircraft.

In short, the RAT is the ultimate aviation backup plan.

Why Was the RAT Invented?

As aircraft became more advanced in the mid-20th century, they increasingly relied on electrical and hydraulic systems for flight control. Losing both engines and the primary power supply meant a plane could quickly become uncontrollable.

Engineers needed a solution that was:

Independent of fuel or batteries
Reliable in emergencies
Simple enough to work with nothing but airflow

The RAT was the answer. Early designs appeared in military aircraft in the 1950s and 60s, and today they are standard equipment on nearly every large commercial jet and many fighter aircraft.

How the RAT Works: Design and Engineering

The RAT may be compact, but its design packs in decades of engineering refinement. Here’s how it functions:

1. Deployment Mechanism

Triggered automatically when all engine-driven generators fail.
Can also be manually deployed by the crew.
Stored flush within the fuselage for aerodynamics.

2. Blade Design

RAT blades are optimized to spin at relatively low airspeeds.
A 2-3 foot diameter propeller is typical, though smaller RATs exist on some fighters.

3. Energy Conversion

The spinning turbine shaft connects to either a generator (to produce electricity) or a hydraulic pump (to provide pressure).
Larger aircraft RATs can produce up to 70 kW of power, while smaller versions may output just a few kW—enough for essentials.

4. System Integration

The RAT doesn’t power the entire aircraft—just the essential “survival” systems, such as:
- Flight controls (via hydraulics)
- Avionics (navigation, radios, displays)
- Instrumentation
- Limited lighting

Real-World Saves: When the RAT Made the Difference

Though rarely used, RATs have played a starring role in saving lives:

Air Transat Flight 236 (2001): An Airbus A330 lost all fuel over the Atlantic due to a leak. The RAT deployed, powering critical systems. The pilots glided for nearly 20 minutes before landing safely in the Azores—saving all 306 on board.
US Airways Flight 1549 (2009): Better known as the “Miracle on the Hudson,” Captain Chesley “Sully” Sullenberger’s Airbus A320 lost both engines after a bird strike. The RAT deployed, giving enough power for essential controls as the crew successfully ditched in the Hudson River.
Military Applications: Some military jets like the A-7D Corsair II rely on compact RATs to maintain hydraulics during engine failure. In combat, this redundancy ensures pilots can still maneuver and eject if necessary.

In each case, the RAT wasn’t the star of the news headlines—but it was the silent hero working behind the scenes.

Commercial vs. Military RATs

While the concept is the same, RATs differ based on mission:

Commercial Aircraft RATs
- Larger, designed to keep passenger jets’ complex systems alive.
- Prioritize avionics and hydraulic control for safe landings.
- Found on Airbus A320, A330, Boeing 787, and many others.
Military Aircraft RATs
- Smaller, optimized for fighter jets.
- Focus on hydraulics and essential combat survivability.
- Found on aircraft like the Eurofighter Typhoon.

Both types share one principle: give the pilot enough control to land—or survive.

Why the RAT Is a Symbol of Aviation Resilience

The RAT represents something deeper than just engineering. It embodies aviation’s core philosophy of redundancy and safety at all costs.

In a world where technology sometimes fails, the RAT ensures that pilots and passengers still have a fighting chance. It’s a reminder that aviation is built on layers of backup upon backup, and that even when everything goes wrong, there’s still one more line of defense.

Engineering Challenges of RAT Systems

While conceptually simple, RATs present several challenges:

Reliability vs. Weight: The RAT must be strong enough to endure high-speed deployment yet light enough not to burden the aircraft.
Testing Requirements: Because RATs are rarely used, they must undergo extensive reliability testing to prove they’ll work under stress.
Maintenance: Though rarely deployed in real flight, RATs still require scheduled checks to ensure instant readiness.

A malfunctioning RAT isn’t an option—its entire reason for existence is to work flawlessly in the worst-case scenario.

RATs in Aviation Culture

Among pilots, maintainers, and aviation enthusiasts, the RAT is often a topic of humor and respect:

Pilots joke about the RAT as the “tiny windmill of hope.”
Maintainers appreciate its rugged design, knowing it’s there when nothing else is.
Aviation fans see it as a symbol of clever design—turning airflow itself into a power source.

It’s the kind of component that doesn’t make headlines until it saves lives—and then becomes legendary.

Closing Thoughts: The RAT’s Lasting Importance

The Ram Air Turbine may be small, but its role in aviation safety is immense. From commercial airlines to front-line fighters, it has proven again and again that when everything else fails, a simple turbine powered by rushing air can keep hope alive.

At Challenge Coin Nation, we celebrate these overlooked heroes of aviation. Whether through custom challenge coins, patches, or collector’s items, we believe every piece of aviation history—big or small—deserves to be remembered. The RAT is a perfect example: a small device with the power to save hundreds of lives.