| Author | Message | ||
     Gregtonn |
I find the advanced concepts of the design to be very promising. The eVTOL capability is especially intriguing. G https://www.youtube.com/watch?v=ZpdDY2rDsLI | ||
| Crusty |
That was quite interesting. Thanks for putting that up! | ||
| Ourdee |
Doesn't take me long to sneak off and plunge down a rabbit hole: | ||
| Chauly |
A friend of ours quit Gulfstream to go work for Lillium. She loves it there... I can see why! | ||
| Hootowl |
Pretty neat. I wasn’t in a place where I could have the sound on. Will watch again later. | ||
| Blake |
Watch the video very closely and skeptically. It's VERY slick, and in my view very deceptive. The flight videos appear to be of an RC aircraft or possibly even CGI in some scenes, which is perfectly fine, if they are open and honest about it. They aren't. The tell is the lack of actual audio and any scenes showing a human pilot. Cockpits with blacked-out smoked glass? Uh... Lots of red flags. Why don't they ever show the full scale aircraft in that pristine factory setting running, or at a minimum a working prototype of its highly touted variable geometry outlet nozzle? At a minimum, you'd expect to see an actual video of that key new tech actually working. Most of the presentation is CGI renderings. It advertises a capacity of seven passengers and a VTOL range of 155 miles but has reportedly never flown more than 3 minutes? Hmmm... https://iceberg-research.com/2022/03/14/stronglili um-nv-the-losing-horse-in-the-evtol-racenbsp-stron g/ http://www.howardsmithlaw.com/SecuritiesFraudCases /Lilium.html | ||
| Hootowl |
It seemed to be a work in progress. I don’t think they were trying to be deceptive. | ||
| Mad_max |
Was it 36 motors? That seems like an awful lot of redundancy to build in. My understanding is, RC flyers don’t scale up very well. I’ve seen RC F35s with EDF motors that hovered very well. Turbine powered ones that fly and sound like a real jet. But this is the only fueled turbine powered F35 RC I’ve seen that flies like the real ones costing $145 million. https://www.youtube.com/watch?v=fElJF9Bd_4o I worry about these companies that are in business for a decade with very little to show beyond their original prototype. https://lightningmotorcycle.com/home/product/speci fications/ | ||
| Aesquire |
https://www.rcgroups.com/forums/showthread.php?205 6389-VTOL-RC-aircraft-concepts-designs-and-links https://static.rcgroups.net/forums/attachments/1/0 /0/1/7/7/a6335487-44-image.jpg The Lilium uses a form of blown flap, with distributed propulsion. ( a fancy way to say multiple fans/props/jets ) It's a Deflected slipstream approach during part of the time, Augmented thrust all the time, and has some "issues" as well as advantages. The reason for the many fans is not just redundancy. When one fan fails it creates a big drag increase and air will "pile up" in front of the lost fan, giving altered, asymmetric lift distribution and effectively stalling a portion of the wing in front of the blockage & behind. It's a pretty clever idea, but there have been a Lot of those in aviation that weren't successful. I follow one of the builder forums and vaporware fund suckers are a common occurrence. Pretty photoshopped pictures of imaginary airplanes skimming the water near famous tourist attractions are popular. ( nevermind the French police and version of our FAA would throw the book at Anyone flying past the Eiffel tower over densely populated Paris. ) You learn to pick out the buzzwords, and hypothetical dream specifications that have no test data behind them. Often planes that never get past a mock up stage. Some darn nifty mock ups too. This applies to other vehicles, motorcycles, cars, private airships, etc. Electric is a buzzword trend particularly powerful now. Might double the crowd funding for your project. There's an interesting actual plane, the Celera, https://ottoaviation.com/celera-500l they makes a buncha claims that might even succeed, partly, if they can get a fuel efficient enough engine for it. One that has actually been flown is a complex beast. https://en.m.wikipedia.org/wiki/RED_A03 Note the emphasis on "sustainable fuel" & biodiesel. Gotta get the fund raising buzzwords! The Celera team just announced they are going to try hydrogen fuel cells. Why? Fund raising buzzwords. And keep in mind they have an actual flying machine that a human has actually flown. A clean low drag design is great, the Celera should be fairly decent compared to a 1953 Cessna. Modern composite construction techniques allow a very smooth curved surface that is very hard to impossible to get with bent sheet metal. Smart design can be light & strong. I'm skeptical that they can meet all their dream goals of carrying capacity ( # of passengers and luggage ) economy, and speed all at the same time, but it's a work in progress, & good luck. The Lilium? Highly skeptical. I would not invest. | ||
| Aesquire |
You want to get excited about one that works?! https://opener.aero/ I'm waiting for the first Black Fly to be sold to a customer, and a final price so I can finally admit I can't afford one.  What makes Black Fly revolutionary isn't the multicopter technology. You can buy that for toys. Home builders have built real man carrying versions, and there are several companies making "flying motorcycle" and " robot air taxi" versions, a few actually available. ( the Human Cuisanart approaches are worth a fun argument, alone! ) The ability to transition from pure thrust lift off to wing borne horizontal flight isn't new, but it's darn hard and Black Fly does it well. ( lots of VTOL craft have failed in that aspect ) No, what's Revolutionary is the seating arrangement. Tail sitters, like the Ryan X-13 are scary hard to fly backwards for landing. The aerodynamics wants to flip the plane around, so it lawn darts. And the pilot is lying on his back, head down unless the seat pivots, with lousy visibility. Only the very best pilots need apply! Pivoting engine & wing designs, like the V-22 Osprey or the Lilium, need heavy complex mechanisms to work. Black Fly cheats. The fuselage rocks in pitch on the ground, tips up for take off and landing, and levels out in wing borne horizontal flight and on the ground for access. So the pilot is sitting in lounge chair position on ground and at cruise, but in a legs up on his back position in hover, take off, & landing. They just bypass the orientation problem with the auto land feature. You have to get to hover over your landing spot, ( Which can also be automated ) and push the Land Now button. They've been hoping for luxury SUV pricing. Since a typical modern Sport plane, ( in the 2 seat Sport Pilot ( US ) class ) is right about $100,000 and so is a luxury pickup truck, ( Ford Limited ) they have a shot at being in the ballpark on pricing. We'll see. Anyhoo... I want one. But I doubt I can afford it. | ||
| Gregtonn |
"Was it 36 motors? That seems like an awful lot of redundancy to build in." Redundancy is far down the list in the reasons for the multiple motors in the design. You may notice that the variable nozzles perform the function of the movable airfoils on conventional aircraft. Next, using several small motors distributed along the wings reduces aerodynamic drag. Thirdly the nozzles can be controlled individually to provide maneuverability and stability in all flight modes. I could go on but perhaps you get the point. It is not a perfect design but, as I said, I find concept tO be intriguing. Also takeoff and landing on conventional runways in a conventional manner could extend flight range considerably. G | ||
| Aesquire |
Redundancy is far down the list in the reasons for the multiple motors in the design. Yep! https://en.m.wikipedia.org/wiki/Rockwell_XFV-12 The XFV-12 used air blown over flaps, slats, ( and other technobabble terms most planes don't use ) from a central jet engine. Unfortunately the loss in pressure through the ducting stole so much energy it was a failure. The Lilium uses the multiple fans/motors to do the same thing, but without the restrictions and all the interior volume taken up with ducts. Heavy ducts. Where fuel would normally go. If course they stuff batteries in the space instead, so it is still a win. There is a similar future plane that uses one big thrust augmented blower on each wing and the tail, like a Dyson house fan. My bet is losses on the air flow will make it an expensive fail. But the Lilium has well understood fans in open ended ducts to compensate for the high loading on each fan. Higher blade loading, more power needed. There's a reason helicopters have huge rotors. It's more efficient, and you NEED that for vertical flight. Ducted fans are more efficient than regular props, if designed properly. Having a butt load of fans &, blade area is one way to do it. The V-22 Osprey has just 2 huge rotors. On almost all of the multicopter designs, including Lilium... If you get total power failure you will want a big red handle to deploy a whole craft emergency parachute. But that's basically SOP on many air craft, from paragliders to luxury fast glass airplanes. ( I have one on my hang glider harness ) I'm skeptical. Not just about the Lilium. But it's EARNED skepticism. Because I've been waiting for this for too damn long & it's Not going to go on sale. https://moller.com/ You might remember the Supertrap muffler? Moller developed it to quiet the ultra noisy wankels he was using. | ||
| Mad_max |
Well thanks for repeating but maybe that’s the wrong word. What I mean is it just looks overly complicated. It’s like, why does a 1st lady who has very few responsibilities need 36 staffers? Nobody bothers to explain. The Black Fly is impressive for what it is. Surprised by suck a low weight but fairly limited by speed and payload. Guessing that’s due to regulations rather than the design’s potential. Isn’t Musk working on some VTOLs? I have more faith in him than most start up companies. | ||
| Aesquire |
...fairly limited by speed and payload. Guessing that’s due to regulations rather than the design’s potential. The Black Fly is built for FAA pt103 operations. So a maximum empty weight, (255 pounds plus allowance for ballistic parachute and the floating hull that lets you fly from water. ) single seat, max speed about 60 mph and 5 gallons fuel. ( basically, it's a bit more complex with stall speed, etc. ) Pt103 covers "ultralights", paragliders, PPGs, ( powered paraglider ) hang gliders, and ultra light sailplanes. Created originally for hang gliders and powered hang gliders, pt103 is meant to assure public safety, ( crashing into a house is unlikely to wipe out people inside ) and allow flight operations of slowish little fringe things. Not allowed in Air Traffic restricted space, ( unless arranged, I've landed at an International airport for air shows ) and a bunch of other regs, like not flying over crowds. The big advantage of that class of air-things, is they're self regulating on flying ratings, not part of the normal Private Pilot licence system. Saves 6-10k$ and means you can just buy one. You have to learn the rules and skills, do silly stunts like a lawn chair and weather balloon cluster drifting through LAX airspace, and they throw a really large book at you. Because Black Fly is a "copter" type, the stall & top speeds don't apply. But empty weight does, limiting range. The FAA is still adapting to electric propulsion. So the mass of batteries is counted in empty weight. ( logic might say to add the 35 pounds a gasoline version can carry as fuel should be added, but that's in committee ) The FAA is Also still writing the rules for multicopter types. Anything that flies on thrust aka most VTOL, gets treated differently than things with wings, or autorotating rotors. ( because wings and autorotation allow a glide to land if power fails ) One safety consideration is there is a range of altitude where falling will kill you, but you're too low for a rocket launched parachute to be certain to save you. So, yeah, regulations limit range and weight, in the particular niche involved. There are other licence classes like Sport Pilot ( 2 seat planes with weight, speed, complexity limits ) etc. that give different size constraints. But wishful thinking can't change the physics. Batteries you can order on Amazon only have so much power density, far less than a gasoline tank. Yes, electric motors are relatively light per horsepower, but modern gas engines are pretty light, and most flying machines have only 1 or 2, vs. typically 8+ for electric craft. It's still early days, and it's kinda rocket surgery.  | ||
| Aesquire |
As to overly complicated? Oh, yeah, you betcha! Your instincts aren't wrong. A multicopter, drone type thingee, needs 6 motors for stable flight with one dead. (8 is better ) The controller for the motors is basically the same as in the toy versions. The charging system computer might be more complicated, certainly weighs more. The Lilium uses a lot of motors to pull off it's aerodynamic tricks. And a far more complex computer system. But, nearly all VTOL craft have more complexity than a typical normal airplane. There are exceptions, like the "tail sitters" like the Ryan X-13, which are just high power to weight ratio craft with funky landing gear, and are seriously dangerous pigs to land. There's a REASON the Harrier designers chose a different, more complex system. Many argue that electronic complexity is a different challenge than physically complex mechanisms. There's a lot more moving parts in a helicopter than a multicopter. | ||
| Mad_max |
Well how about that. They reduced the number of fans from 36 to 30. Still unlikely I could afford one. Aircraft Development Update https://www.youtube.com/watch?v=qZ73PftBfFg The Jetson One has similar speed, payload, flight time to the Black Fly. They were supposed to start at $60K but are more like $92K and they can’t keep up with orders. The BF was rumored at $42K but I don’t think they’ve sold any yet so who can say what the final price will be. I think initial price will be high simply due to demand. Jetson ONE vs Opener’s BlackFly https://www.youtube.com/watch?v=P48Bk4Rmk68 The no license Mosquito Air is under $40K and is a proven design. Not going to be as stealthy as the electric flyers obviously. The biggest practical difference is that you can refuel in a matter of minutes. Mosquito Helicopter | Detailed Factory Tour | How It's Made | Engineering https://www.youtube.com/watch?v=oQ4ENu7QKoY How about an electric flying jet ski? Not sure why they couldn’t put some little wheels underneath and launch from the ground. Maybe the landing is the bigger issue. https://www.maxim.com/rides/flynano-electric-flying-jet-ski-2019-1/ Nice concept. SUZUKI JOINS SKYDRIVE TO BUILD SUPER COOL FLYING CAR eVTOL BY 2025 https://www.youtube.com/watch?v=so_T81xeWpg Also nice concept. Jetoptera's Bladeless Propulsion System https://www.youtube.com/watch?v=Z8ARFa7HE3c Jetoptera Part 2 https://www.youtube.com/watch?v=buflSdO-MDY  | ||
| Aesquire |
I'm highly skeptical on how much power is lost in the thrust augmenter system. Like Dyson house fan, there's a compressor turbine wailing away inside to provide compressed air to the thing. You could use a turboshaft engine, Internal Combustion engine, or electric motors to spin the impellers. That's in rough order of power to weight ratio. IC, Turboshaft, Electric in order of "fuel mass to power/time". I'm very skeptical about drag increases in the ducted "fanless" ( the fan is buried ) design when power is off. Ram air flow in glide will produce large amounts of Induced drag. Induced Drag is the drag produced by Lift. Energy taken from the airstream to produce a force vector. Typically a wing shapes the flow to lift the aircraft, and that takes energy, speed, out of the flow, counted as drag. You normally think of drag as parasitic drag. The skin friction, the interference drag from where struts and corners meet other surfaces, ( air gets compressed & expands back... Takes energy ) and the frontal area drag from shoving air out of the way, and how it closes back behind a moving object. You add all that up for a ground vehicle, plus induced drag from downforce or lift either compressing or extending the suspension. Drag total increases with airspeed. In an flying thing you add parasitic and induced drag too, but the induced drag is a much bigger deal. And in a flying thing, induced drag is highest at slow speeds, while parasitic goes up with higher speed. That's because at lower speeds you have to suck more energy out of a slower flow to stay up. Those "fanless ducts" are big venturis, like a carburetor, squeezing the air to higher velocity and thus taking energy. ( just as wings do ) but being tubes, ( square or round doesn't matter ) there's no net lift on the chassis, so it's pure loss. Plus on biplanes, the pressure decrease over the bottom wing ( & increase under the top wing ) decreases the efficiency, the pressure differential above and below the wings, total, per area. Biplanes are great for giving you more area for a given wing span, and if you look at most biplanes they use the 2 planes as part of a truss to carry the loads, ( with lightweight, but drag producing wire bracing ) but there's Reasons biplanes are now either sport aerobatic craft or WW1 fighter replicas, and not used as airliners. | ||
| Aesquire |
As to the Jetson One... It's a human carrying multicopter like many drones. 8 motor/props for redundancy, good. You should be able to lose one and keep control & land safely. I class these as Human Cuisanart designs. You fall out, wave an arm around incautiously, or fly into a crowd or individual, and it's... Messy. That doesn't mean they don't Work! Just that there are critical safety concerns. The spinning death blades are obvious. The critical minimum altitude for emergency parachute deployment is another. That, ironically, makes it much safer to fly at 300 feet than 30. ( assuming 299 is high Enough for your deployment system. ) A small, slow, craft, like a paraglider, might only need a few hundred feet for a hand deployed 'chute. ( that's what I have for my hang glider ) A ballistic parachute, either cannon ( shoots the parachute from a tube with compressed air or a chemical reaction ) or rocket, ( drags chute out to full extension with a solid fuel rocket ) can deploy under 200 feet altitude... With Luck. Zero/zero ejection seats use a combination of ballistic deployed parachute & tossing the seat & pilot high enough to deploy and slow you before impact. Not only are they complex, expensive, and heavy, the FAA really, REALLY, doesn't want civilians abandoning their flying machines to crash, uncontrolled, into stuff like schools or homes. So ejection seats are basically forbidden for civilians. There's a huge pile of regulation that includes designing aircraft to safely land, if there's a power failure. It's a serious pucker factor thing for most pilots, except those who deliberately fly aircraft with no engines. ( gliders ) And even those of us that are used to gliders, wouldn't be overjoyed to be piloting a regular plane like a Cessna or 757, with dead engines. We just aren't as freaked out by the situation. | ||
| Gregtonn |
Drifting slightly off subject: Not just for EVTOL, this tech looks like it could be adapted to the Osprey aircraft and solve some of the safety and reliability issues it has been having. https://www.youtube.com/watch?v=orLjrswcpxI&ab_cha nnel=eVTOLinnovation G |
