Flight Attendant: A New Age Of Suspension
In the world of cross-country racing, it's all about those marginal gains. Whether it’s wider tires, lighter rims, or even waxing your chain—every little detail counts when it comes to crossing that finish line faster. Most avid mountain bikers have probably heard of Flight Attendant before, it’s not exactly new. After all, it’s been around for over three years, first appearing in the trail and enduro scenes. But it never really broke into the mainstream, mostly staying on limited-run bikes and the bikes of select RockShox Pro riders.
In 2023, there was a cross-country race for the ages. Nino Schurter, widely regarded as one of (if not the) greatest cross-country racers of all time, snagged his 34th World Cup win in Lenzerheide, Switzerland. A historic day, not just because it cemented Nino’s place as the rider with the most World Cup victories in history, but also for SRAM and RockShox, as it marked the first-ever race win on a Flight Attendant-equipped cross-country bike.
Since then, Flight Attendant has gone public for cross-country bikes, officially released in the Spring of 2024—and it’s been a game-changer. From dominating US Marathon events to crushing World Cups, it’s been showing up on the bikes of top racers at every event. It also seems to be making its way onto the bikes of top local racers. So, what’s all the hype about?
What Is Flight Attendant?
Flight Attendant is SRAM/RockShox's electronic suspension system, featuring electronic controls on the fork and rear shock—designed to take mountain bikes to the next level. It automatically adjusts suspension settings in real-time to optimize performance and efficiency based on the rider's terrain, movements, and input. Electronic suspension certainly is not new, Fox's Live Valve system has been around for six years as a wired solution on some cross-country bikes. However, it was never fully embraced by racers and riders, with many continuing to use Fox’s mechanical lockout due to complaints about Live Valve's performance. It’s not all that surprising, given that it was the first electronic suspension of its kind, and Fox is undoubtedly working on improvements.
Flight attendant is based on three modes, open, pedal, and lock. The suspension system rotates through these modes based on rider input, to make them as efficient as possible. By sampling all of the data that comes from the sensors, the fork and shock will account for the changes made by changing the compression in the fork and shock.
This is all about maximizing speed and control. In elite cross-country racing, even small time gains can make or break a race. RockShox testing shows that Flight Attendant can save over a minute compared to their standard mechanical system in an XCO race.
How Does It Work?
Flight Attendant automatically switches between modes as quickly as possible, ensuring it’s always optimized for the rider. But how does it determine when to open, and when not to? The secret lies in the spindle. The original Flight Attendant system used a pedal sensor to determine when to open/close the suspension, using cadence as a factor. With the latest cross-country Flight Attendant, this functionality now relies on a power meter, integrated with 'Adaptive Ride Dynamics,' to make the determination. The power meter uses the rider's power numbers to decide how stiff the suspension should be, with the idea that the more power you put out, the stiffer it needs to be. The LEDs on the fork reflect this with four zones—Low, Medium, High, and Sprint—distinguished by color. The softer the pedal stroke, the softer the suspension will trend. These zones are also customizable to the cyclist's preferences.
The other side of this is data analysis. Under high power, stiffer does not always mean better. In some race situations, Flight Attendant should be more open, even under high power numbers, to hold traction, as this is faster. The system inputs data it gathers from the terrain and rider movement to determine this as well. The system also has what they call 'Split State.' This means that the rear shock can be in the pedal position while the fork is fully open, and vice versa, depending on what is needed to be most efficient and comfortable at that time. The system also learns the rider's style and adapts accordingly. It stores data from the last 8 rides and will constantly adapt. So, as riders train and get faster/stronger, the bike will adjust accordingly.
In addition to the power numbers, there are the individual sensors on the fork and shock. By having two individual sensors that work together, they know where they are in space. This lets the bike know when it is pointed up vs. down, or when it is being leaned into a corner, etc. It also looks at the shaft speeds of the dampers and knows when it's in the lip of a jump, in the air, in chunk, etc. All of this data is inputted to make the bike as fast as possible, stiffening and softening as much as needed.
Making Everything Faster
Most who have ridden cross-country bikes, have used cable-actuated lockouts and might be wondering, 'Is this not just the same thing?' To some extent, this is correct, but that's not the full picture. Yes, it is emulating what a lockout does, but the difference is the speed, split states (the shock and fork lock out independently), and compromise. The biggest difference is the speed of actuation.
A report from SCOTT from 2019 follows Nino Schurter on the Lenzerheide World Cup Course and recorded how many times he used his lockout across the course. This number was 160 actuations of his lockout, spending most of his time in the middle zone (called 'transaction mode' by SCOTT) and the second most in the fully open mode. The first time Flight Attendant was ever raced in a World Cup was also on the same course, under the same rider, and it actuated over 1,300 times. So, over 8 times more usage than a standard lockout, which points to it being in the exact mode it needs to be in at any given time, far more than a mechanical lockout. In this race, RockShox claims this system was 1.8% faster. The Split States of Flight Attendant also mean the fork might have been fully open while the shock was locked at the same time, something a mechanical lockout can’t do.
On a traditional cross-country bike, a lot of racers will set up their suspension on the much stiffer side of things, so even when fully open, the suspension is a little more efficient while pedaling. But on Flight Attendant, the system does this for you. This means you can run your suspension to be more comfortable for descending because the sensors will make it firm when needed. So not only does it make you faster uphill, but downhill too.
The system also lets you, as a racer, just let go and race to your full extent, without thinking. When redlining and breathing out of your eyeballs, the last thing you want to do is think about when to lock out your suspension.
How To Set It Up
To set it up, start by pairing everything to your fork. Hold the AXS button on the fork till it blinks slowly green. Then do the same thing to the shock, once the shock pairs to the fork, the AXS lights will blink three times fast to let you know it is paired. Do the same thing for the shifters, derailler, and dropper post, pairing them all to the fork. Once all paired, open the AXS app. Make a new bike in the app, select add components, then select the name of the fork that pops up. Connect the fork accordingly. Once the bike is connected to the app, connect the power meter by selecting the “AXS Components” button, click the plus, then click add pedal sensor. There should be a box to type in the power meter’s serial number, (located on the back of the spider) then do that. Once everything connected, let the app walk you through the calibration.
Flight Attendant Bikes And Upgrades
Want to get a Flight Attendant bike for yourself? Check out the options from Mondraker, Specialized, SCOTT, Orbea, and Santa Cruz as each brand's flagship XC bike is already loaded with the Flight Attendant. If you want to look into making a different bike Flight Attendant, let us know! Some older bikes are cross compatible as long as we can get the right shock size. Email us at [email protected] to get started.