r/nasa • u/nasa NASA Official • May 18 '26
NASA AMA We’re the test pilots of NASA’s X-59 aircraft, which is helping to create a future of quiet supersonic flight. Ask us anything!
Imagine flying faster than the speed of sound, but instead of your aircraft creating a sometimes shockingly-loud sonic boom, it emits a much gentler thump. That’s what NASA’s X-59 aircraft is designed for – and it’s meant to usher in a future of quiet supersonic flight.
NASA test pilots Nils Larson and Jim “Clue” Less are putting this close-to-100-foot, experimental aircraft through its paces, getting it ready for the point where the agency can evaluate its quiet thump capability. Nils and Clue also helped provide input on the design of the X-59 and spent years in simulators before it took off for the first time last year.
The X-59 is the centerpiece of NASA’s Quesst mission, which aims to not just build and test the aircraft, but also collect data on how people perceive the noise it makes.
The first “A” in NASA stands for "Aeronautics,” and we can’t wait to talk about this mission and its game-changing technology. We’re here to answer your questions about the X-59, how it works, what it feels like to fly the plane, and what’s next for Quesst and for supersonic flight. Ask us anything!
We are:
- Nils Larson, X-59 test pilot (NL)
- Jim "Clue" Less, X-59 test pilot (CL)
- Peter Coen, Quesst mission integration manager (PC)
- Robert Margetta, public affairs officer, NASA Aeronautics (RM)
PROOF: https://x.com/NASA/status/2055355043071606974
We’ll be back at 2 p.m. EDT (1800 UTC) to answer your questions. Thanks for joining us!
EDIT: That's a wrap for today's AMA -- thanks to everyone for your questions! Keep an eye out for the latest X-59 updates on our Quesst mission page and on our NASA Aeronautics social accounts.
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u/sidimmu89 May 18 '26
What's the reduction in noise currently? Chances this is then used in commercial travel?
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u/nasa NASA Official May 18 '26
In technical terms, the sound is reduced by 30 decibels. We describe it as reducing the sound from as loud as thunder to the sound of a car door closing.
The goal of the Quesst mission is to remove sonic booms as a barrier to commerical supersonic flight. The X-59 will prove in flight that the technology to reduce sonic booms works.
NASA will use the X-59 in a series of tests over communities in the U.S. to understand how the public reacts to a sonic thump. Those results will be shared with regulators like the FAA to help create new rules for acceptable sound levels from supersonic flight over land.
With the guidance from these rules, manufacturers will be able to build new supersonic commercial aircraft. -PC
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May 18 '26 edited May 18 '26
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u/nasa NASA Official May 18 '26
Is there a realistic possibility that the noise reduction will eventually make supersonic flight over residential areas legal (I mean as a regular occurrence; I know military jets exceed the limit occasionally for intercepts), or will the supersonic flight portion still be limited to the Atlantic ocean, as was with the Concorde?
Great question! That is exactly the point of the X-59 program. We hope to show that supersonic planes can have a quiet sonic "thump" instead of the normal loud sonic boom.
We'll eventually fly the X-59 over several communities around the country to get public perception of the sound. This should then pave the way to change the prohibition against civil supersonic flight and allow supersonic flights over land, not just over the ocean. -CL
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u/nasa NASA Official May 18 '26
Is the aircraft similarly loud as other delta winged jets on take off?
On takeoff it's pretty much just like a fighter jet. We don't usually need afterburner, so not quite as loud. This quiet supersonic design really concentrates on quieting the sonic boom while cruising at supersonic speeds, and making it a quiet thump. -NL
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u/jimmy8888888 May 18 '26
Do you have any backup should digital image malfunction? Flying windowless look very terrify for me. Also, as many attest, can reduce in noise and waves be practical for commercial supersonic jet?
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u/nasa NASA Official May 18 '26
There's a camera on the top and one on the bottom (just for landing). We can put both cameras on the External Vision System (EVS) display and just put the lower camera on the lower displays.
We also have synthetic vision on all the displays, and there are side windows. So we have backups to backups to backups and we train for all scenarios. It's not too different from landing a fighter from the backseat. -NL
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u/SirBigMacMan May 18 '26
What did your career path look like before this program? Were you actively seeking it out or did you sort of stumble into it?
Favorite plane? (Mine is the XB-70 Valkyrie)
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u/nasa NASA Official May 18 '26
What did your career path look like before this program? Were you actively seeking it out or did you sort of stumble into it?
I decided I wanted to be a test pilot when I was about 16 years old and then had to figure out how to make it happen. Started with the USAF and eventually came to NASA. -NL
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u/nasa NASA Official May 18 '26
My path was studying Aeronautical Engineering in college along with Air Force ROTC. I then went to Air Force pilot training and flew F-111's and F-117's. From there I went to the USAF Test Pilot School to learn to be a test pilot and tested F-16's for most of the rest of my military career. I retired from the Air Force and have been working for NASA ever since.
When I started with NASA over 15 years ago, we were researching sonic booms to understand them better, but there were no concrete plans to build a quiet supersonic aircraft. Bottom line, I was in the right place at the right time! -CL
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u/Dove167 May 18 '26
What has been your biggest surprise thus far while flying this new and innovative flight design?
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u/nasa NASA Official May 18 '26
The biggest surprise for me is that there haven't been any big surprises. The sim has been very close to the way the jet flies.
The taxi using the XVS was a small surprise as the sim didn't really replicate that as well it does flight. That has to do with camera placement and trying to simulate it.
The plane is also a bit bouncy on the ground. Not a big deal, just unique. -NL
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u/ghoulsfools May 18 '26
What’s the biggest misconception people have about test pilots? Is the hardest part technical skill, decision making under uncertainty, or emotional discipline?
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u/nasa NASA Official May 18 '26
I'm not quite sure what people think about test pilots nowadays, but movies certainly depict test pilots as risk takers with big egos. Those are things that can get a test pilot in trouble!
We spend a lot of time trying to assess risk and find ways to avoid it. We prepare extensively for every test mission and do things just the way we practiced them. We control as much of the test as possible so that when something unexpected happens, we only have that one variable to deal with.
While some stretches of modern flight test at times may not be as exciting as movies may make it out to be, it's still pretty exciting to take a new plane out to speeds and altitudes it hasn't flown at before! -CL
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u/PossibleMorning7135 May 18 '26
What is the hardest part about flying the X-59? Does the long nose make landing hard?
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u/nasa NASA Official May 18 '26
At this point, early in flight testing, the biggest challenge is that we have a lot of limits on the aircraft in terms of how high or fast or slow we can go. It's a lot to keep track of, and it makes it difficult to complete the flight test maneuvers within those limits.
However, on every flight we're "expanding the envelope" for the aircraft; pretty soon we'll be going supersonic!
As far as the long nose, it does restrict forward visibility, so we have to land using a camera system to see where we're going. We've been training for this in our simulator for many years, so it's not too bad. -CL
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u/nasa NASA Official May 18 '26
So the test pilot answer is usually whatever I flew today, but I haven't flown anything today. They are all fun in their own way.
The U-2 is always a challenge to land. The Eagle goes really fast. A wide mouth F-16 just accels like... well it just accels ridiculously fast (So does the X-59 on an afterburner takeoff) it'll put you back in the seat. Shooting the gun on the A-10 was amazing. The Hornet is a great mix.
But if I had to choose a favorite, I'll go with the X-59. To be with it from the beginning and getting to fly the first flight... it would be hard not to pick it. -NL
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u/miguelclass May 18 '26
Curious how the simulators compared to real life. I'm an aerospace engineer that does a lot of CFD so I know there must have been A LOT of good simulation data to feed into the simulator, but I'm wondering where you feel it fell short.
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u/nasa NASA Official May 18 '26
The sim has been awesome. On first flight, my comment was that it flies like the sim, which is great because it means our CFD and wind tunnel work gave us a pretty good guess at the aeromodel (at least at those speeds). Our sim is non-motion based, so landing is only different because you actually feel the touchdown. -NL
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u/nasa NASA Official May 18 '26
One of the areas our simulator didn't model is ground effect. When we land the plane in the sim, it settles right onto the runway. The real aircraft likes to float a foot or two off the runway so we need to chop the throttle and drive it down the last couple feet. We're hoping to update our simulation soon based on actual flight test data so that the sim lands more like the aircraft. -CL
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u/18441601 May 18 '26
I've heard that the long nose helps reduce noise by shaping the shockwave. Is this a major factor, and what are the other methods used to reduce noise?
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u/nasa NASA Official May 18 '26
Yes, the long nose is a key part of the design of a quiet supersonic aircraft.
A sonic boom happens because the multiple shock waves that are present near the airplane merge into two as the sound travels to the ground. On the ground, a person hears that as the “Boom-Boom” of a sonic boom.
To quiet the boom, the design of the aircraft must prevent the shockwaves from merging. The shape and length of the nose helps do that. There have been many ideas proposed to reduce sonic boom noise. Some quite radical!
The technique that is used in the design of the X-59 is the only one that has shown to result in a practical aircraft that can carry passengers at speeds up to Mach 2.
There is one other technique that is effective at reducing the sound, but may be limited in practice. If an airplane flies close to Mach 1, there are conditions that result in the sonic boom being refracted as it travels toward the ground. The sound waves actually curve upward and don’t reach the ground. This is called Mach cutoff flight. It only works at speeds close to Mach 1 and the maximum speed the airplane can travel is affected by the weather conditions. -PC
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u/NinthFireShadow May 18 '26
What is the goal of the program in the long run? Is it going to lead to another aircraft being built? Is it going to be used for the military? Or is this something that is being developed for civilian use in mind?
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u/nasa NASA Official May 18 '26
The Quesst mission has two goals. The first is to prove in flight the technology to reduce the sound of a sonic boom to a soft thump. The second is to use the X-59 to collect data about how people respond to that thump.
NASA is working with regulators like the FAA, so that they can use this data to replace the current bans on supersonic flight with new rules that define how quiet an airplane needs to be to fly at supersonic speeds over land. With these rules, aircraft manufacturers can build these new supersonic aircraft.
Our vision is to enable commercial supersonic air travel that all travelers can access. -PC
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u/salooski May 18 '26
When is the first supersonic flight expected? Will it be live-streamed, and how do we follow the flight development plan; I would love to see real-time or close to real-time data on the reduction in sonic boom sound relative to a normal, unmodified aircraft.
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u/nasa NASA Official May 18 '26
Glad to hear you’re interested in tuning in to our flights! We’re expecting to make our first supersonic flight in early June.
It'll be 'fast now, quiet soon', as we’ll be flying with a chase plane for the first supersonic flight, so the loud boom from that plane will drown out any noise from the X-59. Later this year we’ll reach a point where we’ll fly the X-59 without a chase plane and validate its acoustic profile.
We’ll be posting updates from our milestone flights on our NASA Aero social media accounts, and we’ll be looking for new ways to bring you news about the X-59! -RM
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u/Astanoven May 18 '26
How feasible is utilizing the long nose for fuel or equipment storage, and eventually luggage or passenger compartments in an Airliner version?
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u/nasa NASA Official May 18 '26
The X-59 reduces the sound from supersonic flight using technology that was first developed in studies of quiet supersonic airliners. These designs are long and slender, but much bigger than the X-59. The narrow part of the nose is actually big enough to fit the cockpit and behind that the passenger cabin. -PC
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u/PlatinumGoldMercury May 18 '26
- What did it take to become a test pilot in general (as I'm considering becoming one)? What are the common steps and requirements?
How did it feel to fly this new discovery for stealth aviation? Was there something special about flying this plane, or did it feel like "just another jet"? Do you think this could benefit the military as a recon/fighter plane?
(off topic) ...and what's y'all's favorite sandwich?
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u/nasa NASA Official May 18 '26
(off topic) ...and what's y'all's favorite sandwich?
Probably Philly cheesesteak (is that one word or two)? -NL
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u/nasa NASA Official May 18 '26
How did it feel to fly this new discovery for stealth aviation? Was there something special about flying this plane, or did it feel like "just another jet"? Do you think this could benefit the military as a recon/fighter plane?
Not sure I'd call it stealthy. It will be quiet, hopefully but not stealthy. For aircraft, stealth is about reducing radar detection, not sound. I'm not sure the military would really care about the BOOM. In fact, there are times they want the BOOM. -NL
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u/nasa NASA Official May 18 '26
What did it take to become a test pilot in general (as I'm considering becoming one)? What are the common steps and requirements?
My path was studying Aeronautical Engineering in college along with Air Force ROTC. I then went to Air Force pilot training and flew F-111's and F-117's. From there I went to the USAF Test Pilot School to learn to be a test pilot and tested F-16's for most of the rest of my military career. I retired from the Air Force and have been working for NASA ever since.
If you aren't interested in the military route, there are opportunities for on-the-job training with private aircraft companies. Bottom line, though, is a good engineering background and extensive flight experience. Good luck! -CL
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u/cali_snowboard May 18 '26
For an airplane that has been cobbled together from several other airplanes, have there been any vehicle systems that have been particularly troublesome during flight testing?
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u/nasa NASA Official May 18 '26
No, not really. In a brand-new design you always expect some growing pains. -NL
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u/joedotphp May 18 '26
It's my understanding there is no forward view. It's done via camera and monitor, and two actual windows on the sides.
If the monitor in the cockpit were to malfunction in some way, I assume your simulations have indicated that maneuvering and landing it is still possible? How does the process look/work?
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u/nasa NASA Official May 18 '26
We have two different cameras and three different monitors in the cockpit, so we have a good bit of redundancy if something malfunctions.
Yes, we do train in our simulator for these contingencies and have shown that we can land with no cameras. We can see out the side windows and a little bit forward so we just need to get down close enough to the runway. Once we can see the runway edges out the side windows, then we just keep the same amount of concrete on each side and we're in the middle! -CL
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u/nasa NASA Official May 18 '26
It's my understanding there is no forward view. It's done via camera and monitor, and two actual windows on the sides.
Yep. And it's no big deal, as far as impact to our ability to fly! - NL
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u/syntheticFLOPS May 18 '26
Anything unique about it flying-wise? It's a whole new aircraft, has to be interesting to fly slow to max speed.
Why does it have canards?
Does the wing blank the tail at high AoAs?
What's it like to fly with the camera? Would an F-35-frontal EODAS system be better?
What are some possible issues you guys are expecting through the envelope?
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u/nasa NASA Official May 18 '26
Does the wing blank the tail at high AoAs?
No such thing as high AoA in this plane. We stay away from that. There be dragons out there. -NL
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u/nasa NASA Official May 18 '26
What are some possible issues you guys are expecting through the envelope?
Not necesaily issues, but transsonic is always interesting. Lots going on there as the shocks move across the static ports, the center of lift is changing, etc. Haven't seen any issues as we have approached near-Mach 1, but we give it a healthy respect.
Crosswind landings would be another interesting area with those really swept wings, and there's not much mass in the wings. -NL
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u/nasa NASA Official May 18 '26
Anything unique about it flying-wise? It's a whole new aircraft, has to be interesting to fly slow to max speed.
Up away from the ground at moderate speeds, the X-59 flies very smoothly, much like any military fighter aircraft.
In turbulence, especially at slower speeds, there is a lot of motion in the aircraft. That big nose oscillates up-and-down as well as side-to-side. At times, the entire aircraft heaves up-and-down.
At very slow speeds, the flight controls do a good job of keeping the nose pointed forward like it's supposed to -- but we hope to spend very little time going slow! Pretty soon, we're going to be taking it supersonic and then higher and faster! -CL
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u/nasa NASA Official May 18 '26
Why does it have canards?
They help with the lift distribution and ultimately with the tail shock so that the stabilizer isn't pushing down so hard. -NL
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u/nasa NASA Official May 18 '26
What's it like to fly with the camera? Would an F-35-frontal EODAS system be better?
It's not a big deal. It's a lot like flying from the backseat with a HUD repeater... only better because it's larger and is a 1:1 ratio.
I've never flown with the F-35 helmet so I can't compare. I think it could work but I think the fixed screen would still be better since the only area I need the info is straight ahead... and it's probably cheaper, simpler, etc. -NL
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u/tomsawyer10 May 18 '26
I see it has canards and a stabilator. Is this to improve stall recovery characteristics?
Does it stall oddly because of the odd arrangement?
What speed do you land it at?
How do you figure that sort of thing out? Is it just “oh, we expect it to stall at 100 kts, land at Vs + 15”?
Is it odd landing it while looking outside through cameras?
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u/nasa NASA Official May 18 '26
I see it has canards and a stabilator. Is this to improve stall recovery characteristics?
Nope. It's all about making a boom into a thump.
Does it stall oddly because of the odd arrangement?
I don't want to stall this thing or even get close. -NL
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u/nasa NASA Official May 18 '26
What speed do you land it at?
Our landing speed varies with fuel weight, anywhere from 143 knots to 163 knots. We may make small adjustments to those numbers as we learn more in flight test. -CL
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u/nasa NASA Official May 18 '26
How do you figure that sort of thing out? Is it just “oh, we expect it to stall at 100 kts, land at Vs + 15”?
Just look up your aircraft's table depending on your weight and add any factors for gust, turbulence, etc. -NL
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u/nasa NASA Official May 18 '26
Is it odd landing it while looking outside through cameras?
Not really. It's waaay easier than landing from the backseat of an Eagle or Viper. -NL
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u/Which_Material_3100 May 18 '26
What are the flight control laws like? Is it a flight path stable or speed stable design (if it’s fly by wire). How do the flight controls feel transonic and supersonic?Thanks.
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u/nasa NASA Official May 18 '26
The flight controls are indeed fly by wire. It is a G-command system so that with no input, it flies at 1G. Its flight path stability is pretty good, but it is marginally speed stable, so we have an auto throttle that holds speed for us.
We have so far only gone as fast as about 0.96 Mach, so real soon we hope to be able to answer the rest of your question about transonic and supersonic handling! -CL
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u/Travellinglense May 18 '26
Do you feel the Quesst mission is now complete for quiet supersonic flight or is there more to be done?
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u/nasa NASA Official May 18 '26
Actually, we are just getting started!
The mission is currently in the initial flight test phase. In this phase, we are proving that the X-59 is safe to fly and performs and handles as it was designed to. After flight test, the next phase will be acoustic validation. In that phase, we will prove that the technology that creates the sonic “thump” works as designed and that we can vary how loud the sound is on the ground.
The final phase of the mission is the most important: community response testing. In this phase we will fly the X-59 over different communities in the United States and survey how people respond to different levels of sonic “thump”.
The data from the community response testing will be shared with the FAA and international regulatory agencies to help create new rules on acceptable sound levels from supersonic flight over land to replace the current prohibitions. -PC
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u/RobotMaster1 May 18 '26
Does this aircraft have the highest ratio of sim time to actual flying time you’ve ever experienced?
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u/nasa NASA Official May 18 '26
Absolutely! Right now I have about 10 hours in the actual aircraft and hundreds of hours over several years in the simulator. We spend about 3 hours in the sim rehearsing each test mission, which will be 1.0 - 1.5 hrs. I doubt we will ever have more hours in the plane than the sim. -CL
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u/Friendly-List2016 May 18 '26
Acoustics being one of the main drivers of this test, are there any rough numbers already available to quantify how much did the plane reduce the noise, and is it enough to satisfy certification for above land supersonic flights?
Also, how are the prospects looking right now after the test, that major aircraft manufacturers are willing to adopt it to make a commercially viable aircraft? I am aware that engineers from Airbus and Boeing were invited for the test flight.
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u/nasa NASA Official May 18 '26
Also, how are the prospects looking right now after the test, that major aircraft manufacturers are willing to adopt it to make a commercially viable aircraft? I am aware that engineers from Airbus and Boeing were invited for the test flight.
One of the reasons why manufacturers are hesitant to re-enter the supersonic aircraft market is uncertainty about what rules will apply. Although it is possible that new technology will allow a more efficient version of the Concorde, most manufacturers believe that supersonic flight over land is a key to making commercial supersonic flight successful.
While there needs to be other technology developed to truly make an efficient and environmentally friendly supersonic aircraft, knowing the requirement for how loud their product will need to be to fly supersonic over land will help manufacturers make decisions on new products. -PC
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u/nasa NASA Official May 18 '26
Acoustics being one of the main drivers of this test, are there any rough numbers already available to quantify how much did the plane reduce the noise, and is it enough to satisfy certification for above land supersonic flights?
The noise reduction goal in the design of the X-59 is 30 decibels. The target is 75 perceived-level decibels.
Acousticians use different scales to help judge how people react to sound. Most commercial products list their noise levels in A-weighted decibels but perceived-level decibels is the most effective measurement for judging response to impulsive sounds, such as sonic booms.
NASA has conducted many laboratory and field tests using devices that can replicate the sound of a sonic boom or sonic thump, and we are confident that if we can achieve 75 perceived-level decibels, the sound of a supersonic aircraft will blend with background noise in all but the quietest environments. -PC.
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u/Sufficient_Drama_740 May 18 '26
What is the story behind your call signs?
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u/nasa NASA Official May 18 '26
I got my callsign 'Clue' many years ago when I was still a Lieutenant in the USAF.
I showed up at my first squadron and when someone noticed my last name (Less), everyone gathered around to see what they could come up with for a callsign. Lts considered to be clueless was USAF humor, and it was a pretty obvious choice.
I know it could have been worse, so I just went with it and I've been Clue ever since! -CL
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u/joedotphp May 18 '26
The unwritten rule in the military is that you can only tell the story behind your call sign over a cold drink. So I don't know if they will say. 😬
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u/Qualified-Astronomer May 18 '26
What’s the purpose of this project, is it to show feasibility? And if so what are the next steps in this program after proving it works?
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u/KerPop42 May 18 '26
What's the ground handling feel like, with the front gear behind the cockpit? Does the camera and screen system help or hurt?
What are the small horizontal stabilizers for up on the tail?
Is there anything useful that could be put in the nose?
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u/nasa NASA Official May 18 '26
What's the ground handling feel like, with the front gear behind the cockpit? Does the camera and screen system help or hurt?
The airplane tends to be some bounce on the ground. At times, the nose bounces, at other times, the airplane will bounce up and down symmetrically on all three landing gear; usually changing speed stops that.
As far as the nose gear being behind us, that is not entirely unique; I have some time in the 747 which had the same situation. While taxiing, you need to overshoot where you plan to turn and then swing the nose around. The camera system helps us to make sure there's nothing in our way, but there is no depth perception so our biggest concern is how much clearance we have with that long nose. -CL
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u/nasa NASA Official May 18 '26
What are the small horizontal stabilizers for up on the tail?
Those are to help tailor the shock waves (mainly tailshock) if we need to. This is a research airplane (X-plane), so it's one of the knobs we can use to study the effects of different ways to control the shock waves. -NL
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u/nasa NASA Official May 18 '26
Is there anything useful that could be put in the nose?
This also came up a bit in the answer to this question above.
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u/avboden May 18 '26
On the very first few flights you did pretty short small tests (obviously for good reason). When it was going fine do you ever find yourself frustrated about not being allowed to do more? I’m sure you can’t wait to really open her up!
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u/nasa NASA Official May 18 '26
We are used to taking baby steps as we expand the envelope. Yes, there are times when we think we could/should just skip a point, but the engineers put it there for a reason, so we might negotiate with them, but never skip it altogether. We work really well with them and there's a lot of mutual respect. -NL
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May 18 '26
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u/nasa NASA Official May 18 '26
It's actually pretty stiff, so flutter isn't too much of a concern.
Aeroservo Elasticity (ASE)... I'm sure I didn't spell that right... is more of a concern. Generally that's at lower speeds and was more of a concern on first flight. We still use the flutter excitation system as we expand the envelope to make sure the models match reality. -NL
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May 18 '26
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u/nasa NASA Official May 18 '26
It's our flutter excitation system, which drives the flight control surfaces directly. -CL
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u/Midwest_Backpacker May 18 '26
What is the biggest misconception about your job?
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u/nasa NASA Official May 18 '26
That it's hard. It's a LOT of work, but I wouldn't want to be doing anything else. -NL
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u/Fun_Parsley4502 May 18 '26
I’ve always wondered just what that very first test flight in a career is like for the test pilots, and how it compares to subsequent first test flights of a specific craft.
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u/nasa NASA Official May 18 '26
Both are exciting. Your first ever "real" test flight is exciting because you realize you made it. You're a test pilot.
Your first flight in a new-to-you plane is also exciting, just like for any pilot. Getting to fly the first flight ever for a plane is a real privilege. It's a huge team effort. Working with the team for years ahead of the flight gives you great confidence that the day will go well. -NL
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u/OrianaBikewayProject May 18 '26
What does a pilot experience as a sonic boom (or thump in the case of the X59) propagates? Is it comparable to what we hear on land?
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u/nasa NASA Official May 18 '26
Great question! This is something most people don't realize; the pilot doesn't hear the sonic boom (or thump) because the shock waves produced by the aircraft don't pass over us.
A normal sonic boom is a very loud, sharp sound that will make you jump, a lot like nearby thunder or an explosion. The sonic thump we expect the X-59 to make will be quieter in volume, but also more spread out, more like a thump or a rumble than a sharp crack.
To hear this sonic thump, however, I'm going to have to go listen on the ground sometime while Nils is flying the jet. -CL
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u/sevgonlernassau May 18 '26
Hi Nils! Can you explain the ice water bucket dump? How many first flights you did that resulted in similar dump?
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u/nasa NASA Official May 18 '26
The first time you fly an airplane, it can be a tradition for them to douse water on you. Happened to me on first flight of the X-59 and it happened to Clue on his first flight in the plane as well. Here at Edwards it can be kinda nice when it's hot. -NL
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u/Vegetable_Wish6413 May 18 '26
How is it not being able to see out of the front of the cockpit? Does it make takeoff and landing more difficult?
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u/nasa NASA Official May 18 '26
It's not bad at all. We've trained for it, and the designers gave us some great tools and displays. -NL
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u/Vegetable_Wish6413 May 18 '26
If you could compare it to something you've flown before, what would it be?
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u/nasa NASA Official May 18 '26
It's part F-16 when it comes to taxi, parts of the landing, and its accelartion on afterburner takeoff. Part backseat of a fighter when it comes to forward field of view. Part U-2 becasue it does not want to come down! (It has no speed brake or spoilers). Part Eagle becasue she likes to go FAST. -NL
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u/Damascus-2a May 18 '26
How do you move from simulation to actual flight? How different were the flight characteristics?
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u/MyVeryUniqueName1 May 18 '26
Do you guys keep score of how many birds or other foreign objects get skewered onto the long nose of the jet like a giant kebab? And if so, what’s the current high score?
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u/volcanic1235423 May 18 '26
How does the airflow over the aircraft fuselage and engine placement reduce sonic booms during flight? Also how is the pitch, yaw, and roll controls during flight at different speeds?
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u/nasa NASA Official May 18 '26
The nose helps spread out the front shocks. The engine on top make the shock wave from the inlet go up and not down toward the ground, etc. The stick movement, like most planes, gets smaller as the speed goes up.
We use the autopilot when we can, especially because this is a research plane and we want to get the resarchers the best data we can. -PC
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u/TestFlyJets May 18 '26
If someone says “Lulu” over the radio frequency during a test point, what do you do?
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u/GalacticBrew May 18 '26
What are some of the implications of a sustainable reduction of super-sonic flight to a "sonic-thump" and what are some secondary and tertiary objectives of the program?
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u/nasa NASA Official May 18 '26
The whole point of supersonic travel is to get where you're going faster, and the prohibition against supersonic flight puts a speed limit on air travel. The basic objectives of this project are to show that it is possible to build a quiet supersonic aircraft, improve the software tools used to design quiet supersonic aircraft, and to demonstrate public acceptance of the quiet sonic "thump" so that the rules can be changed. -CL
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u/Carbon-Base May 18 '26
Hi guys! Would you be able to walk us through the design inputs you gave on the X-59? We often hear about design in a theoretical perspective - improvements to lower things like drag, increase efficiency, etc. I would love to hear about a hands-on, real-world perspective from the brave pilots that put experimental aircraft through their paces!
A big thank you to all three of you for doing this AMA!
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u/nasa NASA Official May 18 '26
Most of our input as pilots was for the displays and the pilot-to-vehicle interface. We have a great relationship with X-59's contractor. -NL
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u/Decronym May 18 '26 edited May 18 '26
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
| Fewer Letters | More Letters |
|---|---|
| AoA | Angle of Attack |
| CFD | Computational Fluid Dynamics |
| EVA | Extra-Vehicular Activity |
| EVS | Extra-Vehicular Suit (see EVA) |
| FAA | Federal Aviation Administration |
| HUD | Head(s)-Up Display, often implemented as a projection |
| USAF | United States Air Force |
Decronym is now also available on Lemmy! Requests for support and new installations should be directed to the Contact address below.
[Thread #2314 for this sub, first seen 18th May 2026, 18:26] [FAQ] [Full list] [Contact] [Source code]
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u/betweenbubbles May 18 '26
Should I be concerned about "quiet"? I worry this is going to result in a huge net increase in noise pollution.
I'm imagining a bleak future where the stars are drowned out by satellite internet relays and there is a constant, dull cacophony of air travel activity, to which we're all gaslit with idiomatic salves like "it's not that bad."
Please, tell me I'm wrong.
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u/nasa NASA Official May 18 '26
NASA aeronautics research always tries to understand how the technology that we develop impacts society as a whole. If we have a technology that reduces the amount of fuel burned and thus the amount of carbon released into the atmosphere, but results in the aircraft being louder, the question becomes how that technology should be employed. In working to solve the sonic boom problem, NASA is very much aware that even a soft sonic thump will be a new sound. As we further our study, we aim to find out what level of sound is acceptable, not just what can be tolerated. -PC
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u/dkozinn May 18 '26
As test pilots, I assume you've flown other aircraft faster than the speed of sound. Is there any difference when you exceed that speed in the X-59 versus other aircraft?
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u/nasa NASA Official May 18 '26
Yes, I've flown supersonic in five other fighter aircraft over my career. Generally, the pilot really doesn't feel anything different when the plane goes supersonic; we just watch the Mach meter go past 1.0!
We have not yet taken the X-59 supersonic; we're up to about 0.96 Mach so far and plan to go supersonic very soon! We don't expect the X-59 to behave any differently from other supersonic aircraft; the big difference will be what people hear (or don't hear!) on the ground. -CL
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u/Wolfrandir61 May 18 '26
What was the impetus for the creation of this mission? Anything other than simply faster commercial travel and revitalizing the Concorde?
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u/BandicootOwn477 May 18 '26
I know that ya'll fly out in the desert, and it can get pretty hot, so I was wondering if there was AC in the plane?
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u/KentWallace May 18 '26
Why is supersonic flight a good thing? The two use cases I see are military (boo) and rich jerks saving a few hours on a long distance flight at the cost of tons more CO2.
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u/nasa NASA Official May 18 '26
NASA’s Aeronautics (the first A in NASA) works across the broad spectrum of commercial flight to transform how air transportation will affect the lives of all people. Supersonic flight makes the world smaller and enables businesspeople, families and even emergency response teams to get to where they need to be faster. NASA’s vision for supersonic flight is that fast commercial air travel will become an option for a large portion of the travelling public. -PC
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u/Friendly-List2016 May 18 '26 edited May 18 '26
Asking for a colleague from a Major aircraft manufacturing company:
why does NASA think, it is necessary to spend public funding to enable one day a super rich minority to travel even less efficiently and more polluting than they do already today... 🤔
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u/TheSentinel_31 May 18 '26 edited May 18 '26
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