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RockShox Flight Attendant auto pilots your suspension with wireless electronic adjustments

rockshox flight attendant control module fork
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The all-new RockShox Flight Attendant Wireless Electronic Suspension Damping combines data from sensors at the fork, rear shock and cranks arms to, automatically switch your suspension damping between Lock, Pedal and Open modes.

By sampling rider inputs, trail terrain, and suspension position every 5 milliseconds, it ensures your suspension is always in the most efficient setting for whatever you’re riding.

rockshox flight attendant electronic suspension damping fork shock crankset sensors
Flight Attendant Components on a Canyon Neuron, including Fork Control Module, Shock Motor Module and Crankset Pedal Sensor. The FA components have a 308 grams weight penalty, depending on the spec; that includes fork, shock, pedal sensor, both SRAM AXS batteries and the difference in weight between a 1- and 2- button left controller.

At launch, Flight Attendant is only available through SRAM’s OEM partners, so expect to see this new technology on the top-end models from Canyon, Specialized, YT and Trek over the coming weeks and months. Here’s everything you need to know about SRAM’s new electronic suspension technology.

SRAM Flight Attendant

sram flight attendant rockshox axs suspension
The Flight Attendant Electronic Suspension System is only available as a 3-part system composing Crankset, Fork and Shock; the system relies on data captured at each of these points to adjust the suspension’s damping support in real time.

Forget fiddling about for lockout levers mid-ride; SRAM’s Flight Attendant Electronic Suspension Damping is here to put your bike’s suspension on auto-pilot, leaving you free to concentrate on the ride.

The new technology relies on data received by sensors at the fork, rear shock and crank arms to automatically tune the level of damping support at any given moment. It introduces a host of new componentry, all designed to work together seamlessly through the SRAM AXS Encryption Wireless Network.

rockshox flight attendant control module fork
LEDs on the Fork Control Module indicate which mode the Flight Attendant is in at any given moment; these also indicate the Flight Attendant’s bias setting… more on that later.

The Flight Attendant Control Module is at the heart of operations. Housed on top of the fork damper, the Control Module collates data from the fork, shock and crankset, pushing it into the Flight Attendant algorithm to make suspension damping adjustment decisions.

It’s worth pointing out that Flight Attendant is 100% wireless, and completely self-contained within their fork, shock, and spindle…there are no additional sensors required on the bike, so there’s no wires to run anywhere.

The Fork and Shock house accelerometers measuring G-Force and Pitch, information relating to how aggressively the rider is riding, how hard they are cornering, the roughness of the terrain and the steepness of the terrain, too. The Crankset Pedal Sensor simply measures whether the rider is pedaling or coasting; it does not measure pedaling torque or power.

sram flight attendant crankset pedal sensor axs
The Flight Attendant Pedal Sensor that sits inside the SRAM XO1 or XX1 Cranksets to monitor the rider’s pedaling inputs

Every 5 milliseconds (that’s 200x per second), the Flight Attendant is able to switch the suspension damping between Open, Pedal and Lock modes to give the rider the most efficient suspension damping characteristics for the given terrain. Low Speed Compression and Rebound adjustments remain a manual affair; more on that later.

Which Rockshox forks use Flight Attendant?

rockshox flight attendant ultimate mtb forks pike lyrik zeb electronic suspension
The 2022 RockShox Pike (120mm-140mm), Lyrik (140mm-160mm) and ZEB Ultimate Flight Attendant Forks (150mm-190mm)

The new Flight Attendant technology ushers in a new era of suspension technology for RockShox, with the launch of three new high-end forks, rear shocks and cranksets. The concept strikes us as most appropriate for XC racing, but it is RockShox’s mid- to long-travel forks that will be the first to take advantage of Flight Attendant; namely, the Pike Ultimate Flight Attendant, Lyrik Ultimate Flight Attendant and ZEB Ultimate Flight Attendant.

We expect the SID version make an appearance at a later date. These don’t replace any of RockShox’s current fork offerings – they simply sit at the very top of the range above the current Ultimate level forks that run the Charger 2.1 RCT3 damper.

How does it work?

specialized enduro s-works axs flight attendant
The Specialized Enduro S-Works with a full complement of SRAM AXS Componentry including Flight Attendant fork, shock and crankset

So, how does the Control Module prioritize the information it receives from the fork, shock and crankset sensors? SRAM tells us the system takes data from all sensors to paint a picture of the terrain and adjusts the damping according to the input received.

“Flight Attendant’s highest priority is adjusting the system to the open position when bumps or disturbances are detected and will adjust the system to be more efficient when it senses the rider pedaling”.

sram axs left hand 2 buttom controller reverb post flight attendant suspension
The new RockShox Left Hand 2 Button Controller allows you to cycle through suspension positions, overriding Flight Attendant, and it operates the RockShox Reverb AXS dropper post too – compatible with MatchMaker X

All well and good, but, we wanted to know just how quickly it is able to do that. Let’s take a Bike Park lap as an example. You’re hammering on the pedals on the run into a jump, and the Flight Attendant automatically switches your suspension to Pedal mode to give you the most efficient pedaling platform. When you take off, and your suspension effectively tops-out, does Flight Attendant know to switch the suspension back to Open mode to absorb a big hit upon landing?

flight attendant sram action shot table jump
Flight Attendant System is completely water and dust proof to IP69K

“There is not a clean answer to this question as a ton of factors influence how quickly the system will react,” says Chris Mandell, Rear Shock Product Manager at RockShox. “However, the thing to understand is that: as we developed the Flight Attendant system it became very clear to us that relying on speed alone would not allow the system to provide the rider with a seamless experience.”

“In the algorithm we blend the systems’ speed, rider input, bias setting and input from the sensors to provide the rider with consistent and predictable performance. Last week I had this exact experience in Bend OR. I was riding the jump trail there and found I had to pedal for the larger gaps to clear them. System worked brilliantly – It was open when I wanted and expected it to be.”

Flight Attendant Bias Control

rockshox sram flight attendant axs app bias control

The behaviour of Flight Attendant’s Auto Mode can be tailored using the SRAM AXS App. You can adjust the algorithm, instructing it to bias more toward the Open mode, the Lock mode, or you can choose to keep it neutral.

Switching the bias setting to -1 or -2 adjusts the Flight Attendant’s algorithm, telling the system to favor the Open mode, with reduced likelihood of it slipping into Lock mode. Alternatively, you can set the bias to +1 or +2 to produce the opposite effect, adjusting the algorithm to favor the firmer Lock mode. This would likely be more appropriate for more mellow rides that involve a lot of climbing on fire roads and smoother surfaces. RockShox tell us that Lock mode offers the same Lock Out force across Pike, Lyrik and ZEB forks. It is said to be firmer than the Lock Out of the Charger 2.1 RCT3, but softer than that of RockShox XC forks.

sram flight attendant system bias control favor lockout

The Zero bias setting is neutral, with no bias toward any mode. This could be the most appropriate setting for an XC or big mountain ride where you’re likely to encounter the most varied terrain, requiring the suspension to adapt more frequently along the way.

That said, Chris Mandell tells us that the bias adjustments are more about personal preference than what terrain you’re riding, saying “the system does not care if you are in a bike park or on an XC trail. In either location the system will read the terrain, rider input and bias setting to provide appropriate suspension states”.

sram flight attendant low speed compression adjustment via axs app

And if you don’t want to use the AXS App, you can mostly get away with that as there are mode preference buttons located on the top of the fork, too. And Rebound adjustments are all made using the usual knobs and dials on the suspension itself located in the usual places.

But, this automatic switching between Open, Pedal and Lock modes is independent of Low Speed Compression (LSC) and rebound adjustments, all of which are manually controlled…but only through the AXS App, without external manual controls.

The new Flight Attendant forks get 10 clicks of LSC adjustment and 20 clicks of rebound adjustment.

What happens when the Flight Attendant sensors and Control Module run out of battery?

Before powering off, the Flight Attendant reverts the suspension setting back to Open mode, leaving your suspension in its most trail-capable and descent-friendly setting.

2022 Fork Chassis, DebonAir+ Spring and ButterCups

rockshox lyrik ultimate flight attendant 2022 lowers arch detailing

The launch of Flight Attendant Wireless Electronic Suspension Damping brings with it new chassis for the Pike, Lyrik and ZEB forks, as well as an all-new DebonAir+ Spring.

The most notable change is the addition of pressure relief valves located on the lowers. These give the rider a mess- and tool-free way of quickly releasing air pressure that has built up in the lowers after a long, arduous descent, or following big changes in elevation; their purpose is much the same as that of the lower leg bleeders seen on the FOX 38.

2022 rockshox lyrik arch detail

While the ZEB fork chassis remains largely unchanged, the shorter travel 35mm stanchion Pike and Lyrik forks get updated chasses with a more aggressive aesthetic. The crowns see a little more machining, perhaps to save on weight, while the arch on both forks is a lot more sharply contoured, and also more heavily machined at the sides. We’re waiting to hear back from RockShox to find out how these updates have altered the forks’ stiffness and strength characteristics.

rockshox debonair+ air spring cartridge

Rockshox revised their DebonAir cartridge in 2020 with a larger negative air spring and relocated transfer port dimple to deliver easier setup and smoother small bump performance and mid-stroke support.

Now, they’re introducing DebonAir+ with an even larger negative air spring, which they say delivers even more buttery smooth small bump feel, better support, and a higher overall ride height for more confidence when things get steep. Comparing the ZEB DebonAir+ Air Spring with the earlier DebonAir Air Spring, you’ll notice a “top hat” – it is this region that provides the additional volume for the larger negative spring.

RockShox says that this, coupled with their ongoing friction reduction efforts, has created a linear spring curve from the beginning of the travel through the mid-stroke.

rockshox flight attendant damper buttercup vibration damping pucks

On top of their automatic electronic adjustment capabilities, the Flight Attendant forks get vibration damping inserts that sit just underneath the gold housings on the end of the damper and air spring.

Called ButterCups, they are basically two rubber pucks designed to absorb high frequency vibrations from the trail, stopping them travel up through the fork into the handlebar and eventually into the rider’s hands. SRAM reckon these go a long way to reducing hand and arm fatigue by blocking up to 20% of vibrations.

Side note: We covered the science behind vibration reduction benefits, and rounded up several products that further reduce arm pump if you want to maximize comfort and minimize fatigue-causing vibrations.

RockShox Super Deluxe Ultimate Flight Attendant Air Shock

rockshox super deluxe ultimate flight attendant air shock

Like the Ultimate Flight Attendant forks, the Super Deluxe Ultimate Flight Attendant shock also benefits from the new DebonAir+ air spring. It gets an increased negative spring volume, adjustable by the rider with the use of tokens, similar to what you’d normally use for positive chamber volume adjustments.

In addition to 20 clicks of LSC adjustment that can be made via the SRAM AXS App, the Super Deluxe Ultimate Flight Attendant shock gets 15 clicks of rebound adjustment, making it way more tuneable than the regular Super Deluxe Ultimate which offers just 9 clicks of adjustment. Chris Mandell tells us the rebound damping range itself has increased, with an improvement in the fidelity of the adjustments too.

specialized enduro rockshox super deluxe ultimate flight attendant electronic suspension shock crankset pedal sensor
Though only available on Super Deluxe Ultimate Air Shocks for now, it’s not impossible that a Flight Attendant Coil version will be offered in future.

The nature of the shock will differ dependent on the bike it is spec’d on, as each manufacturer is able to specify the specific air cans (progressive or linear) as part of the custom tuning process. These air cans will be available aftermarket however, they are not compatible with current Super Deluxe shocks.

SRAM Flight Attendant Cranksets

yt jeffsy sram flight attendant xx1 crankset pedal sensor
The YT Jeffsy fitted with Flight Attendant Wireless Electronic Suspension Damping Componentry, including the AXS Pedal Sensor housed within an XX1 Crankset – the system only works with these Flight Attendant Cranksets, and cannot receive data from existing power-meters or cadence sensors.

Flight Attendant will initially be available on higher end bikes spec’d with SRAM XX1 and XO1 cranksets, though it is compatible with most DUB spindles except the DUB 83 (DH) spindles. The cranksets are Direct Mount only, compatible with 30T, 32T, 34T and 36T chainrings. Options include 52mm and 55mm chainlines, with crank arm lengths of 165mm, 170mm and 175mm.

sram xo1 xx1 flight attendant cranksets axs pedal sensor

Pricing & Availability

At the moment, the SRAM Flight Attendant System is OEM only, coming on complete bikes from YT, Canyon, Trek and Specialized, with some other manufacturers lined up. The Flight Attendant suite of components, including forks, shocks and cranksets will be available aftermarket in due course, but we’ve no indication as to when that will be. Stay tuned.

SRAM.com

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16 Comments
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Tim
Tim
2 years ago

I can reach down and operate the switch myself for free and am not sure I would pay anything for this device. I bet most people are with me, but there will be enough people who are willing to pay a lot to fund the next round of devices, which I imagine will be more effective and control compression and rebound damping. Given that this system requires the use of their cranks, this is another way to force integrated systems on riders who don’t want them.

Andrew
Andrew
2 years ago

I wouldn’t call it ‘Forcing’ if people have an option to buy a bike with this or not…. which they do.

eddiecycle
2 years ago

I can handle a noise happening when I press a button, but little motor noises going on constantly is a dealbreaker for me. I also think that just cycling through the 3 compression modes that forks already have is a pretty rudimentary use of algorithms and all that extra cost. I would have rather seen either a simple wireless suspension switch on the bar or something like a more advanced implementation of the fast-switching valves that Fox released. Loud, expensive robot thumb is a disappointment

Bryan Cola
Bryan Cola
2 years ago

People already hating in this without using it. Same as wireless shifting. I am all for this tech. Why not try to make things better?

patrick
patrick
2 years ago

Any idea if current Quarq power meters could perform the functions needed? It sure would be nice not to need an extra piece when you already have an expensive crankset.

Speed565
Speed565
2 years ago

So now an ultra-expensive high-end bike can require up to 9-10 separate batteries, and the condition of each one needs to be taken care of ?!
SRAM AXS gears – 2 batteries
SRAM AXS Reverb – 2 batteries
This RockSHox thing – 3 batteries
GPS computer – 1 batterie
Plus light and optional sensors

Shimano Di2 and Fox Live central batteries doesn’t sound so stupid anymore.

Tim
Tim
2 years ago

OK, I was being hyperbolic. But it is an attempt at integration (i.e., mutual incompatibility) of not just drivetrain parts, something which we already have a lot of, but also of drivetrain parts with suspension. Want the best suspension? Well, you’re going to have to buy our cranks, then! This approach won’t work yet because the device doesn’t offer much value, but if/ when the device offers real suspension improvements, that will be a different situation.

Hexsense
Hexsense
2 years ago

hmm, if it can lock and unlock so often, can it do some weird wizardry stuff like lock only on each down stroke during the pedaling motion and then open to absorb bump at the top and bottom of the pedal stroke? It’s something inertia valve like Specialized Brain can’t achieve.

Hurricane
2 years ago

Why not just ride a bike with a DW link or CBF link and you won’t have to lock out your suspension. My Turner RFX with 160mm rear/ 170mm front, I never use the lockout levers.

blahnblahblah
blahnblahblah
2 years ago

cant wait to see the price of an s works running this

Ed.
Ed.
2 years ago

and auto locking the suspension when you reach 300+w

Seraph
Seraph
2 years ago

Haters gonna hate, but I am all about this system. Looking forward to seeing it as an aftermarket option so I don’t have to buy a new fork and rear shock.

Kyle
Kyle
2 years ago

Are some of the folks commenting under the impression that this is just a wireless remote lockout?

mark Hagen
mark Hagen
2 years ago

Surprised they introduced this in the more gravity/trail categories and not XC (although i wonder what it weighs?). You think the XC crowd would be a little more open to it. I’m a bit skeptical being not a huge fan of the Speci-Brain but i’m sure you can tune it accordingly to work well.

Cory Benson
Admin
2 years ago

@blah, ha check it out for the low, low price of $12,500.
https://bikerumor.com/2021/10/06/rockshox-flight-attendant-mountain-bikes/

paquo
paquo
2 years ago

not sure but i would think the x country market is a much smaller slice than trail so hey go where the money is

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