Video

[@jetrep]

I'm sure Peter doesn't characterize the raptor project as a failure but certainly most everyone else does. Incredible that after that failure his solution is to create a heavier, more complex aircraft.

[@g.zoltan]

Not necessarily heavier, as the NG is unpressurized, this is huge weight savings. Peter also said that the hybrid drivetrain is lighter than the previous one. The box wing is also much lighter than the high AR wings of the Raptor 1. I have no clue how the hybrid can be lighter, I think it wouldn't be out of character for Peter to say that because he knows the large weight of the hybrid is its greatest flaw. Also, some comments reveal to me that the pressurization of the Raptor was one of it's main selling points, and it's gone now. I think this should've been discussed in this video.

[@Mike-01234]

@@g.zoltan I saw another company is testing a hybrid converted Cessna 337 where one engine is electric hybrid powered it's used during take off and climb at cruse power is reduced to one engine the power isn't needed at high altitude cruse. I have heard 337 owners already do this shutting down rear engine feathering the prop that is what someone said on FB have no clue if that is true or even allowed in the handbook. The one thing I like about the idea of one electric hybrid is your not getting the weight of a IC engine electric engine will have power of IC engine but not the weight. Until battery storage technology is increased by some break through in technology I don't see electrics being used in aircraft.

[@gtr1952]

That was very interesting! Thank you for doing the research and presenting it so well! I followed the Raptor project for about the last 3/4 to the crash. I'm glad it's down and totaled, and nobody got killed in the process. Sorry if that sounds harsh, but he would not listen to anybody or anything. This might have been the best possible outcome. Thanks again... 8) JMHO --gary

[@flybywire5866]

I agree, nobody killed was the best possible outcome. Its a miracle it went that way. When i saw the video of the first test flight i thought that will never ever end well. If someone told him something is a bad idea, he made sure to incorporate it.

[@mercedescherokee6853]

I dont think he completed a lessons learned on useful load from his original combine

[@Triple_J.1]

If they can solve the weight issue, to bring enough fuel for long range, it could be an "international harvester"

[@Tsedek_ben_Shimon]

If he switches to a fluidic propulsion system instead of electric fans it would double the range. Fluidic propulsion is twice as fuel efficient as bladed systems and VERY quiet. Jetoptera has already built and flown a model of their design using this technology which appears to be far superior to the current electric engines available.

[@andrewsampson5659]

I am looking forward to Peter's comment on this video! If we ever get another video from him! Like I said when I first saw the new NG design pics - Its a total waste of time and money - over weight (again), under powered (again) - you can't argue with basic physics and aerodynamics.

[@jwboll]

You forgot to take into account the integration challenges that will be faced when installing the most important component, the air conditioner.

[@creightonking8436]

Haha.. so true.. AC works but it doesn’t fly worth a darn.. the new NG stands for a No Go

[@philpotter6388]

No. Cupholders.

[@aviator267]

This is the kind of R and D information you pay real money for. 👏👏 thank you for the research and effort you put into these videos.

[@daveb4446]

Except most of it is BS and he’s ignoring several existing prototypes. Ignorance is not a valid source.

[@leoa4c]

I have been doing research and design for my own light aircraft (light according to European regulations). I did consider a petrol-electric configuration. On paper, it looks fantastic. It offers limitless packaging solutions, good redundancy if two engines and motors are used, it allows one heaven-like degrees of design freedom. Beautiful. However, the weight penalty is absolutely massive! The generators, the motors, the cooling, the weight of the cables themselves. By the time that you place any amount of fuel to go anywhere, you are out of your class. I didn't even think of using a battery. Surely, it would've increased the empty weight by, at least, 25%. It's unthinkable. Regardless, if the Raptor NG is going that route, placing the fans right on top of the suction side of the wing is not the best solution. It will create a good amount of interference drag while the fans are running, and should one fail, there will be yaw and roll moments to counteract with limited surfaces. Something which is not helped by the fact that one or both wings will lose a significant amount of their lift. Placing the fans on pylons would be the logical solution.

[@Hajduk12]

The very moment I saw Raptor NG video few months ago, I posted a comment that it will not work. I work in surface mining and have been around hybrid power plants since early eighties. My conclusion on hybrid powered general aviation airplane was very much the same as yours, the biggest problem is the weight penalty for unnecessary power conversions from mechanical to electrical and back to mechanical (engine-generator-electric motor).

[@electricaviationchannelvid7863]

So how come Airbus is in a design phase of hybrid blended wing aircraft?

[@Hajduk12]

@@electricaviationchannelvid7863 What do you mean "hybrid blended"? When I was talking about "hybrid", I clearly talked about engine (e.g. internal combustion or turboshaft)-generator-electric motor. Do you have a link with more info?

[@daveb4446]

You mean the hybrids that are currently in the air being tested?

[@electricaviationchannelvid7863]

@@Hajduk12 hybrid refers to the propulsion system...blended wing refers to the design of the fuselage and wing shape...i used to have a video about it...

[@electricaviationchannelvid7863]

@@daveb4446 there are many versions of hybrid, it is a general term...fuel cells can be a part of it or fusion reactors or nuke batteries...or liquid batteries...capacitors...solid state batteries...or synthetic fuel...ion drive... the tech you see today commercialized was developed 20 years ago...

[@azcoyote007]

Hey hey hey. That sounds like science and FACTS buddy! No place for that in vaporware aircraft design!!!

[@daveb4446]

Sure, if you completely ignore everything we learned from the several ducted fans that are currently flying. This guy is a complete moron.

[@azcoyote007]

@@daveb4446 The guy who designed the Raptor? Agreed. Complete snake oil salesman.

[@RobertoRMOLA]

Thanks for your analysis! At that table you showed us comparing Lyc TSIO-540, GM LS3 and Mercedes M139S you forgot one very important parameter: rotational speed. Lycomings generate that amount of horsepower with only 2700 rpm and DIRECT DRIVE. LS3 and M139S produces that figures with much, much more rotational speed (5900 rpm and 6750 rpm, respectively), what demands compulsorily the use of a Propeller Speed Reduction Unit (PSRU), the Achilles' heel of the Raptor design (and any other PSRU equipped aircraft). Moreover, Peter Muller advocates the use of diesel engine instead of gasoline because of the future (almost current, indeed) lack of offer in several airports of the latter fuel. I don't think he's wrong in this choice, but he was completely mistaken with Audi V6 engine + PSRU option and I told him years ago when he was still laminating basic parts for his plane! The problem with diesel engine operating at high altitude - that he miraculously imagined - is the fact that you cannot restart the engine with low dense air without external forced induction (turbo AND mechanical compression). Such thing make it difficult or impossible to use such powerplant. I suggested the use of a conventional aeronautical engine as an interim powerplant, but I've received several anger response on that and I've decided to back off and only watch his progress. I confess that I was very distressed in each test he did. Other disturbing factors was an almost religion of fans supporting his actions. Such thing can be very unpleasant and dangerous.

[@rv6ejguy]

I don't think you grasped what I was comparing. The LS and M139 would be driving the generator directly in this case. No PSRU needed now. I agree on the rabid fan base comprised mostly of people who have no idea about anything technical or mechanical, egging him on and shouting down actual learned folks trying to help Peter succeed. They seem pretty silent now...

[@RobertoRMOLA]

@@rv6ejguy I apologize, I didn't really get the essence of your explanations... At that moment I was trying to do several things at the same time and I ended up losing the thread... I rewatch the video to get the idea. Well, that's really very complex to choose an engine and adapt a generator+battery to it expecting to have reliability, performance and fuel efficiency. Even in a car it would be a huge mental task to achieve systems integration, even more so in an airplane. I consider this Raptor NG a very bad idea, not only by the anomalous aerodynamics, but, especially, by the propulsion system presented. You pointed the "killer" factor: weight. IMO, the original Raptor could prove (or not) the aerodynamic concept using that beefy and healthy TSIO-540, but, apparently, budget was a factor, as well.

[@rv6ejguy]

@@RobertoRMOLA No worries. I agree, the concept could have worked with a real aero engine and real engineers designing the airframe.

[@vitordelima]

Without a proper APU this design is doomed, and those are expensive.

[@phoenixrising4573]

The religious devotion/enabling is definitely a phenomena that has become more and more of an issue with broadly shared projects from charismatic individuals. It's a vicious cycle of enabling and tribalism.

[@wagner24314]

it will have major roll instability

[@phoenixrising4573]

The PJ2 is a really cool looking aircraft, going to have to go research that one a bit.

[@marcv2648]

I found this analysis to be very interesting.

[@golfmaniac]

I followed Peter for several years. It was interesting and entertaining, but the further it went and the heavier it got, you could see it was going to be a failure. I could never see what the purpose of it was. He designed a slightly better looking Velocity, that was never going to fly as well as a Velocity. This new plane will be the same, a lot dreams, no substance.

[@Argosh]

He's resistant to advice and since he is apparently unwilling to learn from his massive warning shot I fear he won't die of old age...

[@Mike-01234]

Velocity is working on a Truboprop now I'm thinking of building the Velocity SE but power it with the Honda K20C1 racing turbo engine they sell as a crate motor 306HP 2 Liter engine for $6500 need to find a reduction gear box for it.

[@Dragon-Slay3r]

Pegasus?

[@Triple_J.1]

@@Mike-01234 ditch the highly boosted automotive engines if you want to fly in your lifetime. That PSRU would be a years long project in itself for an expert powertrain engineer. And whats the point of Turbo 300+ho without a constant speed propeller? Who is going to make one of those custom blades, pitch, controls, etc for you for less than $20,000? Nobody.

[@terencedunn]

Have you seen his newest vid? Now it is a 3 fan vtol aircraft. I would love to see an updated video on his new pipe dream.

[@BGTech1]

I just saw it. With proper development the original raptor could have been successful. But this new vtol design is just about invisible.

[@JosephHHHo]

Awwwwyeahhhh, I've been waiting for this!

[@e36s50b30]

Me too!!!

[@aviator267]

Me too.

[@josephjolly1936]

Thank you, great video.

[@localhawk1]

thank you for this video, answers a some really interesting questions. how little I know ... thanks

[@TeddyLeppard]

Jetoptera seems to be rock solid in their concept and execution. Just hope the company can attract enough capital to make it to production.

[@rv6ejguy]

It will have low propulsive efficiency and a low lift to drag ratio compared to conventional aircraft.

[@william1863]

Slits in the ducted fans will eliminate drag and speed issues look into it. 👍✝️

[@creightonking8436]

But Wait... if you dream it and hope really hard then physics and reality don’t matter....

[@thomasaltruda]

Nice job doing a breakdown on technology and examples of what’s out there. A lot of us doubt that Peter will have much success in delivering his wild claims, but you really put the time together to show why! Thanks! NG is a cool looking design though, I’m sure there will be more uninformed people to send over some money to him…

[@davidbeck1474]

Xt6

[@captarmour]

After all that work with the Raptor what makes sense would be to fix the structural issues and triple the power. my 2 cents

[@ianrs4685]

The raptor was an interesting concept, and did have potential, pity didn't have a metal prop and a gearbox with a few more NACA ducts,. but this thing I've seen larger rear wings on a hatchback, looks like it was designed by the 12-year-old me.

[@GerhardPohl]

Peter was flying the Raptor to Idaho. The only GA aircraft manufacturer in Idaho is Daher (TBA) who bought Kodiak a few years ago to acquire a US manufacturing and marketing base. They also did a lot of work on the Airbus E-Fan and had a contract to build a hybrid version of the E-Fan. The Raptor NG looks very much like the cancelled hybrid Airbus E-Fan. Much of the development work was paid for by Airbus. Similarly, lots of work has recently gone into Prandtl Box Wing planes. Carbon fiber makes them now economically realistic, this was not the case 100 years ago. In short, not as unrealistic as you think! 😃

[@rv6ejguy]

Interesting, however even Airbus can't defy the laws of physics. Raptor NG, as envisioned, will be heavy and slow compared to something like a Velocity XLT which has existed for years.

[@gpaull2]

Wait, technology has advanced in the last 100 years?!?! 🤔

[@sssbob]

All that matters is that it looks cool.

[@troygleeson738]

I agree for the most part, however, depending upon the exhaust nozzle size and relationship and blade pitch, a ducted fan can be optimized for any speed below mach (they do not generate-or should not-the pressure ratio for above mach). The efficiency spread can be broadened by a variable area nozzle, going form divergent to convergent. A high bypass turbofan is nothing more than a ducted fan with a turbojet core and they operate at high mach numbers at reasonably efficient cruise power points, but there is a penalty to be paid on the static thrust end. A properly designed duct will increase the thrust due to the accelerated flow around a properly shaped inlet lip and tip gaps need to be kept under 1% of blade radius to eliminate tip losses. You are right about the electric hybrid. They are just a very expensive, inefficient and heavy constantly variable transmission that add to the overall heat load. NASA has done a lot of research lately about wake ingestion into ducted fans for use on high efficiency next gen airliners. The reason wake ingestion is not used currently is that it disturbs air into the core engine and offers the blades uneven flow and thus higher fan stress but it offers efficiency gains. In order to make a fan work, you have to take advantage of all of these things, but a hybrid system is a non starter.

[@tinolino58]

Are you shure?

[@troygleeson738]

@@tinolino58 it isn't possible to be sure. I am convinced enough to commit it to hardware and find put for sure.

[@rv6ejguy]

Fan design is a big compromise when driven by the relatively weak (compared to turbofan engines) piston or electric motors we are talking about here. Commercial turbofans can optimize for cruise conditions because they have such an excess of thrust available for takeoff with huge hp available from the turbine plus jet thrust from the hot section. My point in showing these 3 flying ducted fan designs was to illustrate that even with nearly 400hp in one small 2 place design, none of these can exceed 160 knots, whereas something like the Virus can do this with only 80 hp, propeller and fixed gear.

[@troygleeson738]

@@rv6ejguy commercial turbofans are designed for high mach (divergent duct to the fan face) and overcome that with sheer power. This is indeed a recipe for failure with a lower power unit. With all due respect to the russian aircraft, it is neither small nor low drag. The l39 replica was very carefully designed over a decade. I read all of their published papers. Their fundimental design decision to try to emulate an existing design was a mistake. It is always a mistake when you need to optimise for a performance mission. This was the fundimental error in the russian design as well. Design is the art of comprimise and negotiation. They gave up most of their negotiating power for a specific form despite those forms being less than optimal. A small, highly loaded fan will not make high returns in static thrust, horse power for horsepower. But I believe it can be integrated into a design that has lower overall drag at speed. In any case, all of this will be either proven or disproven. I have built this propulsion system and am building the airframe now. I will let you know how it goes if you are interested. Otherwise I really appreciate your research on the subject of cooling and the Meredith effect. And with respect to raptor ng: not a snowballs chance in hell. He was better off keeping and refining it when it had real wings.

[@rv6ejguy]

@@troygleeson738 Very interested in your fan experiments. The PJII was designed first to look something like a MiG-29 or similar and that design priority resulted in major performance compromises. The UL-39 similarly affected by trying to make it look like the real L-39 as much as possible. TO distance and top speed in both cases are not impressive for installed power and weight compared to propeller driven designs.

[@dvsmotions]

This design won't even make it to the point where it could crash. We won't see a lot of info about this one before it's scrapped.

[@44bgood]

Good overview! Open propellers also have the same linear thrust falloff with velocity. ShaftPower=eta*thrust*airspeed. Drag of the duct itself is the real issue (if memory serves)

[@rv6ejguy]

Yes, propellers have a similar reduction of thrust with speed however much more disc area and hence higher efficiency to begin with. It looks like from the UL-39 data that fan efficiency will be below 50% above 200 knots where good props can still produce up to 85%. The PJ-II with a small airframe and nearly 400hp comes nowhere close in speed to something like a Lancair Legacy with 50-80 less hp.

[@44bgood]

@@rv6ejguy how do hi bypass turbo fans get around this ? High number of blades?

[@davidr8309]

@@44bgood a hi bypass turbofan also has the core of the engine. The bypass is doing more of the work when you are low and slow. The core is doing more of the work when you are high and fast.

[@rv6ejguy]

@@44bgood Thousands or tens of thousands of hp and lots of blades.

[@aGabay]

​@@rv6ejguy The main problem of ducted fans is the fact that they are kind of a hybrid: they are propellers, which are "power animals" and they are also kind of jets, which are "thrust animals", if you look at it from a thrust generation point of view (using the duct as a fixed, radial wing). You need high rotational velocity to make the duct work well, and you need to have really exact tip-duct tolerances. Too tight of a gap and the blade tip vortices collide with the duct, creating excessive drag and too wide of a gap creates turbulence on the inner surface of the duct, again creating drag.

[@gmcjetpilot]

Honda jet has engines on pylons over wing. Bolting engine direct on upper surface is a no no. Interference drag. Wing configuration is poor for all reasons mentioned, plus intersection drag. Not like Prius automobile, which has parallel configuration, gas engine or electric motor can drive car. This Raptor II is all electric with APU. Train's, Submarine's and some Ship's have a similar configuration, diesel or gas turbine drives generators to charge batteries and power electric motors.

[@willhartsell2283]

if i recall the Chevy Volt ( Not the Bolt) also used a serial hybrid powertrain vs the parallel in a Prius

[@PistonAvatarGuy]

@@willhartsell2283 It was originally intended to be a series hybrid, but series hybrids are hideously inefficient, so there are certain conditions where the engine drives the wheels through a clutch. Sorry for the repost, but had a major brainfart when I made the last comment.

[@nssherlock4547]

Good points.In a development video, Honda jet stated they moved the engines to pylons on the wings instead of the cabin, to also reduce cabin NVH.

[@davidclark3304]

Many of us have become disillusioned as we watched the Raptor fail to meet it's performance expectations in the test flights. I, perhaps among many, am disappointed that Peter has apparently abandoned his original design, which was approaching production, in favor of something completely new that will require years of development. I don't know how he financed the Raptor project, but probably his backers will get discouraged, and my expectation is that we will not hear from him again until he announces a decision to sell the project.

[@rv6ejguy]

It wasn't really anywhere close to production no matter what Peter said. Had to solve multiple major issues first, then test and freeze the design before production could begin. The Audi engine and his redrive would also have had to go. All that would have taken at least 2-3 more years. That being said, with a proper re-design, the original Raptor would be a lot more viable than NG ever will be.

[@brookrestall3274]

Cool, but,...... - Upper wing will experience flow disruption from fuselage at high angles of attack. - If the upper wing were to be comprised of the two outboard sections (from the original design's wings) basically formed into one large section spanning the winglets, it would still add interference drag where each winglet connects to the upper wing. - The fan shrouds cannot be embedded into the wing without a severe drag penalty as well as - aerodynamic (flow) issues created around and in front of the shrouds which may well create flow issues into the fans.

[@briangill2804]

Good video. As an engineer, I appreciate an actual science-based analysis of Peter's latest comedy of errors. A lot of what you had to say about ducted fans is new to me, but the folly of an electric hybrid powertrain is obvious on sooo many levels, as you pointed out. But mostly, what's the point? What does he even hope to gain with all that added weight, cost, and complexity? Most people automatically assume that because hybrid cars are efficient, the same is true of planes. Wrong! The only real thing that makes hybrid cars inherently efficient is regenerative braking. Normal cars convert braking energy to waste heat...hybrids convert it to electricity. That's why a Prius gets unbeatable city mileage, but unremarkable (for an econobox) highway mpg. Perhaps Peter realizes his latest Rube Goldberg contraption will be making so many forced landings that it actually will be able to take advantage of regen braking, LOL!

[@willhartsell2283]

really good stuff but a few questions. I get that the ducted fan may not be optimal, but in the graphs showing thrust vs speed, it would be great to show a 'comparible' fixed pitch prop just for a comparison. Also with regards to the effeciency of hybrid power trains, there are a few attributes that should be considered, 1) the engine can be sized/tuned for a specific power range that it 'always' runs at. you dont need to factor in a broad power/torque band like you do with a traditional power plant. I have no idea if this would offset some or all of the quoted 12% loss but it would be an interesting follow up. The engine could also be underprovisioned as it doesnt need to be sized to allow for max thrust 100% of the time. the battery could be used as a buffer to make up the difference for things like max power vs max continuious power etc. There is also the potential benefit that the engine could be shut down and restarted in flight as power demands dictate. But then again there is the 'penalty' of hauling around a bunch of dead weight when the engine is not running. It would be an interesting thought/engineering exercise to see how much of that power delivery loss could be recovered especially as it pertains to potential overall powerplant weight reduction. I assume this early on in the cycle their would still be substantial weiight penalties to all of this tech. not to mention complexities and reliability issues. It seems a turbine would be the best fit with regards to constant power power production, weight, simplicity but obviously not fuel burn and cost

[@rv6ejguy]

With a 50KWh battery that you can only draw down to 20% for longevity maybe, that's 40KWh. With twin 200KW motors (continuous rating), that's 400KW/ 536hp. The battery can only provide 40/400 or 1/10th of an hour at full power (6 minutes). For climb, this thing would need full power to be used so you can see with the power losses involved (536/.88) it really needs something like a 600hp engine to be able to drive those motors/ fans to be able to climb for more than 6 minutes. This is the big difference between cars and aircraft. A Tesla needs about 10.5 KW to cruise at 70 mph and 31KW at 100 mph. This thing would need at least 260KW to do 175 knots up high. The Tesla has a 1200 pound battery- 85KWh. With the turbo generator added, you might be able to get by with a 480hp ICE to do the job. Probably a mildly turboed LS would be the best choice. Also note that generator output is usually de-rated about 3% per 1000 feet for cooling purposes due to reduced air density. I didn't cover that aspect as the video was getting long already. That becomes a very serious concern at 17,000 feet as that's 50%. So liquid cooled is needed or a gen rated 50% higher at SL. Many reasons why this concept will flop IMO.

[@vitordelima]

@@rv6ejguy I wonder how ships, trains and other older hybrids deal with this issue.

[@rv6ejguy]

@@vitordelima None of these care much about weight and have to fly...

[@vitordelima]

@@rv6ejguy But an entire battery as energy buffer isn't viable for any of them.

[@rv6ejguy]

@@vitordelima The battery is a backup to get the airplane down safely if the ICE fails.

[@gmcjetpilot]

Peter should stick with original configuration but narrow the fuselage (44" cabin is plenty wide, his 62" wide yacht sized cockpit is draggy). Airframe must be way lighter, and it must be un-pressurized saving more weight. Flight control system, NO side stick with cables. Go floor mounted sticks with push-pull rods all on bearings (cables for rudder OK). Last the engine, either a Lyc TIO540 or Continental TIO550 with hyd MT prop. No radiator needed for air-cooled engine, and no PSRU needed for direct drive engines. It would be lighter, less drag, more thrust and have far more performance and reliability. Of course "Velocity" is a popular well established 4-Plc EAB kit plane in almost identical canard pusher configuration.

[@tinolino58]

Build a velocity

[@gmcjetpilot]

@@tinolino58 No you build a Velocity. I built a RV-4 and RV-7, short field, aerobatics, fast XC plane VFR/IFR with excellent range for a bargain. PS I have no desire to build or own any canard pusher.

[@nielsf2743]

Yup.. mostly I agree. Except the wide airframe may pay its way if it’s a lifting shape. (See Celera 500). I’m hoping someone with a bottomless pit of money and a ton of engineering expertise could develop a Diesel engine. It will be a cheap alternative to a gas turbine. Avgas is getting scarcer around the world, we need a JetA fueled power source. It was the diesel (JetA1) power of the Raptor which got me hooked on the concept.

[@gmcjetpilot]

@@nielsf2743 I hear you. But the autodiesel was it's downfall. The Diamond D62 twin diesel ($1.2M) is everything and more that Peter dreamed of.

[@Golf_Cart_Customization]

That's not how efficiency is calculated for a system. You don't subtract the percentages...you multiply them. .95 x .98 x .95 = 80%. My first time seeing your videos but maybe this isn't something you normally calculate.

[@ERusstbucket]

And if you use a calculator for the equation you provide that comes out to 88.445%, not 80%. Is there something I'm missing here?

[@Golf_Cart_Customization]

@@ERusstbucket nope. Made a mistake when I was typing it into my calculator.

[@rv6ejguy]

I went over this again and thought I'd summed the values after your comment but I did multiply them. Anyway always good to check my math!

[@Golf_Cart_Customization]

@@rv6ejguy you didn't really make a mistake. I did. Lol. Good video.

[@robertoler3795]

there are significant challenges with this design :)

[@PMMM9]

Look at the latest video where the builder shows his design mock-up for his fan design. How will these blades deal with ingestion of debris, birds etc?

[@rv6ejguy]

They won't. Not to worry about debris or birds, this fan design as is, will never power anything into flight and will never likely even be built. Check out my last vid discussing this fan design in detail. It can never do what is claimed.

[@andrewjamez]

Peter is back at it again. Check out his old channel.

[@anthonyhunt701]

I love the fan design. I know P&W has been messing about with that👍🏻 think something similar to the PJ-2 work on the Velocity to lower drag on the wing a bit? By maybe going undeneath? Are you building or have built R/C proof of concept for the Velocity?

[@tanguyadriaenssen9755]

And thereby crushing peters dream... again! But he won’t know until he builds the thing and tries to fly it

[@daveb4446]

Ross was zero percent correct about the original raptor. Literally zero of his predictions came true.

[@nathanielcohen9890]

ducted fans would be good for ultralights where your max speed is 63 mph.

[@vitordelima]

Without a carefully chosen and tweaked APU, battery size, ducts and fans, most of what you said is accurate. The push for hybrid-electric had other motivations, batteries are far from being suitable alone, and you can use the electric power anywhere on the aircraft, which is important if you have a VTOL. The technology is still too immature, not only the batteries aren't advanced enough but also the power density of the motors and generators. All of them have improvements being prototyped, but not available.

[@vaughnbay]

Nice vids! How about doing an objective and critical look at the Kerlo "VooDoo" project. That one should roll your socks. It looks to be the diametrical opposite of the DarkAero approach to design, materials, construction and test. Wish the poor soul doing the envelope expansion flying good luck!

[@comptegoogle511]

With the TDI technology and a hybrid motor, it would make a lot of sense to go with a high-compression Detroit diesel and a multi-stage electric supercharger. I agree with all the aerodynamic flaws that you point out.

[@rv6ejguy]

The weight of that would far exceed what was already laid out in this video. Hybrids don't make sense for aircraft at all.

[@comptegoogle511]

@@rv6ejguy If you have a three-stage turbo linked to a permanent magnet electric motor/generator to take care of the compression ratio of 1 to 12 and a two-stroke engine to take care of the compression ratio from 12 to 30 you would have a light and compact engine with a lot of punch when the electric supercharger pushes the air inside the engine and an economical engine when the exhaust turbo recuperates the energy for the electric motor. If you cool the air with an intercooler at every stage it would be even more efficient. A TDI system allows a higher compression ratio because it eliminates the knocking danger and a two-stroke gives you twice the amount of bangs for the same block size. Also, a Detroit engine has a simple check valve system for the intake requiring no cams. So no it won't be heavier. In one sentence, it would be a piston/turboprop/electric hybrid.

[@rv6ejguy]

@@comptegoogle511 BSFC of 2 stroke diesels is about the same as legacy SI aircraft engines (.38 to .40). The DD8 weighs 1400 pounds (1000 more than the SI engines I mentioned) and only develops 350 hp which is about 100hp less.

[@comptegoogle511]

@@rv6ejguy If the engine has an aluminum block, a 30/1 compression ratio, and an exhaust turbo to recuperate the energy normally lost in a two-stroke... fr.wikipedia.org/wiki/Audi_R10_TDI

[@comptegoogle511]

en.wikipedia.org/wiki/Audi_R10_TDI

[@cotyharney9730]

I found this video very useful and answered a lot of questions. Any chance we can talk one on one? Your knowledge could be very helpful

[@rv6ejguy]

I am glad you found the info I presented useful. I'm not sure NG warrants much more analysis. It will be a complete failure as an efficient and fast means of transport in the form we see it here. About all I have to say on it has been said in the video.

[@michaeljarvis6882]

I think it would come down to, blade's, what you're using to create electric, weight but feasible

[@venusreena2532]

Current Fi turbos are a bit different.. Ide opt for the entire F1 engine package.. used of course .. In a Velocity RG

[@philpotter6388]

Thanks, Ross. As usual, an intelligent analysis of Peter's poorly thought out dreams.

[@daveb4446]

Sure, if you ignore that most of what he says is BS and there are already existing aircraft that disprove it.

[@markspc1]

Hello Peter, long time no see you. Have you taken in consideration that gasoline/diesel have a 50:1 power density advantage to batteries ?

[@zain786ification]

What's your opinion about celera bullet plane .

[@rv6ejguy]

I don't see it meeting their original claims nor being a commercial success with the Red engine. Turbines rule this market.

[@m12345678963]

Thank your for the time you put into this. Could you explain why a ducted fan does not work as good at high air speeds. I hate to say it but the do look "cool" and I have wondered why someone did not make a direct drive ducted fan aircraft with a LS motor. I'm sure If it was practical someone would have already done that and from w non engineer the dusted fan does not look a lot different from the high bypass jet engines. Just interested in the why the fan is not as efficient as a propeller. Thanks again, just trying to learn a little more. Ps I fly being a corvair engine with a propeller, old tech but it works just fine for fun flying.

[@rv6ejguy]

The ducted fan has high disc loading compared to a propeller. I provided examples of flying fan driven aircraft to show that high speeds are not their forte with low powered piston or electric motors driving them. Large turbofan engines have tens of thousands of hp to drive the fan and have substantial exhaust thrust as well. That's a different world. Direct drive fans would have high blocking flow in the duct from the cross section of the engine.

[@m12345678963]

Thank you.

[@chrism9976]

It looks like a knock-off of the Jetoptera J2000.

[@ubermenschen3636]

@2:09, this conceptual design of the Raptor NG has so many negative aerodynamic factors against it that the plane designer was an art student rather than an aircraft engineer. Basically, it’s DOA.

[@ronnl001]

Fools and their money are soon parted.

[@gmcjetpilot]

So how much money have you lost? 🤔

[@sheshankutty8552]

Hybrid is inefficient, but might provide redundancy in an engine failure. :-) Most small aircrafts do not fare well when things go south especially with engines failing. As far the ducted fan, there are efficient designs with close tolerance, but it would still have the drag from ducting.

[@rv6ejguy]

Can you point me to some ducted fan designs which even perform within 20% of comparable propeller driven ones? The battery weight to complete even one circuit on a design like Raptor NG would be at least 200 pounds.

[@phoenixrising4573]

Based on the render, there's really no redundancy in the system as presented. He appears to be presenting a full electric driven fan unit, which means if the electrical system fails, the piston system fails as well.

[@sheshankutty8552]

@@phoenixrising4573 Sure he did not render internals of that plane, LOL,

[@MrAutospec]

I compared LH-10 Ellipse to Celera 500L and I can`t believe Celera can go twice faster! What do you think?

[@rv6ejguy]

It won't in real life. Laminar flow will be disrupted with a few bug impacts on the wings, nose, tail etc. but even then, I think their original numbers were fantasy. Folks that can afford multi million dollar airplanes don't buy piston powered ones, they buy turbine. They don't care about fuel burn.

[@MrAutospec]

@@rv6ejguy Thanks! What do you think about new Celera diesel engine RED A03?

[@rv6ejguy]

@@MrAutospec Looks through the replys. I answered this a couple times already.

[@vitordelima]

@@rv6ejguy The idea was saving money for charter companies, not private aircraft. If it is that big with comparable performance to a high level piston airplanes (Velocity, Cirrus, ...), it's still a valid product.

[@vitordelima]

@@rv6ejguy Still without active aerodynamics it will be very hard to do what they are claiming.

[@ronboe6325]

I'll submit that since the IC engine will get 20-30% efficiency the over all efficiency is going to be much worse. I have no idea how efficient the fans will be but we can safely assume they won't be 100%. Power was big problem in the original design so he has managed to make a much more complicated way to produce even less power. Then, as you pointed out, some serious problems with the aero design.

[@Colin_Holloway]

The Formula 1 M/GU is interesting in that they using the motor phase to eliminate turbo lag on acceleration!

[@rv6ejguy]

Yes, but we don't care about that aspect here in aircraft where turbo lag isn't a factor.

[@VanWarren]

excellent analysis, counting the cost, saves so much money and wasted time in the long run.

[@georgeingram9157]

Tesla model S motors are only good for about 50hp continuous. Most motors can also be used as generators. Reluctance motors and generators offer the highest power to weight, but have finicky drive requirements. But even with the best motors and generators, NG would still fly like a turkey, if at all.

[@AndyRRR0791]

Ross being a party pooper here again. Where's ya magic wand, mate...?

[@rv6ejguy]

I think Peter will be the one needing the magic wand... His first design was an utter failure and so will this one be.

[@AndyRRR0791]

@@rv6ejguy That's why I mean. The guy needs help!

[@Finder245]

What I find frustrating about the Raptor NG concept is that it tries to do too many things at the same time. It would make more sense to just build a Cozy as a platform, demonstrate and test the new features of the plane individually on that, keep what makes sense, and build a new plane around that. Trying to do so many new things at the same time is a recipe for disaster.

[@bartofilms]

I hope Peter reviews this and takes some of the valuable info onboard. Based on your assessments, there are a few redesigns that could be done somewhat easily ( I think...): 1. Increase wing area and raise the upper foil slightly to avoid vortices from fusilage and nacelles. 2. Mount the nacelles on pylons like HondaJet. 3. Run a bunch of LiPo battery clusters in series, but step them through capacitors before powering motors. Must have well regulated charge/flow controller units to prevent the LiPo's from over-heating. I think LiPo clusters would weigh considerably less than your estimate , but they are more expensive and more charge volatile than conventional Lithium power cells like Tesla currently runs.

[@rv6ejguy]

This layout is going nowhere as currently designed- even with major changes.

[@nielsf2743]

The original Raptor was nearly a good idea. At least it could take off and fly…. sort of. I wonder how many million dollars of investor funds is sitting in that corn field. This new one is just a joke. Peter can’t be serious with this idea. I sincerely hope that he’s publicised this contraption to get people talking because for sure it will never get airborne.

[@jacobbaker58]

Multiple linear generators (free piston motor) would have a better thermal efficiency than a turbine. About 57percent efficiency this could reduce the battery size and allow for redundancy.

[@rv6ejguy]

Who is making these? Proven reliability and longevity?

[@vitordelima]

@@rv6ejguy Some research labs. No.

[@papakurt862]

I wonder when Peter will start taking deposits on this one

[@nevillecreativitymentor]

St. Peter must hate you!! You were right on the money with the Raptor. They say in aviation ATTITUDE is everything ... I mean like how many levels of correct is that!!!?

[@davidpierce9330]

I wouldn't touch anything with Raptor in the name with a 10 foot pole...

[@jonathanhuman7333]

Only the F22

[@georgeingram9157]

I recommend a much longer pole.

[@superskullmaster]

Nah, this guy is done.

[@BrandonPrado1]

I have a friend who purchased the previous model and was supposed to receive it by December 2018 and he’s been waiting and waiting and apparently he’ll die before receiving it

[@rv6ejguy]

The project completely folded a year ago and deposit holders were offered refunds. Your friend probably wouldn't have wanted one of these as it didn't meet a single projected performance goal. A complete dud.

[@lukebayliss9127]

Even if you could get your head around distributed propulsion in a GA aircraft, I genuinely don't understand why he is going distributed ELECTRIC propulsion. As far as I am aware, train's are literally the only place those systems make sense due to low traction. There's a reason drive shafts have been around for centuries with little change besides materials.

[@MrBlincster]

But aint propellers always more efficient than fans?

[@rv6ejguy]

They appear to be, up to about 300-350 knots. Certainly in the piston powered GA market.

[@discus239]

What do you think Peter is really up to with this? He has a certain level of smarts, wouldn't your viewpoint click with him?

[@rv6ejguy]

No idea what's he's really up to and it could be complete misdirection, but if he continues with the hybrid electric fan idea, it will fail bigger than Raptor 1 with regards to performance. Only his own viewpoint clicks with him. He disregarded multiple experienced people trying to help him succeed with Raptor 1. I don't expect that hubris will change with NG. Raptor 1 or something like it with a turbo Lyconental could have worked with some revisions by real engineers. The pressurization was the key. Without that, it's just an inferior copy of the Velocity.

[@gpaull2]

Separating fools from their money?

[@Jacmac1]

You have 30GPH of fuel burn for the Raptor NG at 17K feet @ 175 knots. Do you believe the Raptor NG would be capable of such speed at any fuel burn rate at 17K feet? Considering all of the efficiency losses that add up and the overall weight, I don't see this proposed design being capable of anything but low altitude flight at a lumbering rate. I don't see how it could possibly hold four people with fuel and get off the ground at all, unless there is some breakthrough with ducted fan technology that Peter isn't telling anyone about.

[@rv6ejguy]

No. I gave the most optimistic numbers possible and believe if it ever flies in this configuration, it will be even slower than this which is why I said it will be a failure.

[@simonbaxter8001]

@rv6ejguy What do you think of his latest (march 2023) videos on the fan design and detailed NG design?

[@rv6ejguy]

All nonsense. I'll respond in the future.

[@UncleKennysPlace]

A video just dropped, and no, it's not feasible, at least as the designer specifies.

[@wayneyd2]

Now that the Raptor crashed. They now move on to steal yet another somebody else idea. AGAIN!

[@jefferyclark2114]

Nice kill piece. Thar said,I've seen a very similar design do some amazing things recently. What say we see what the test flights reveal?

[@rv6ejguy]

Please direct me to the similar hybrid ducted fan design you're talking about. I am not aware of another one that is flying. Thank you.

[@tinolino58]

Oh Peter.. 😳

[@JT203L]

Before I even watch this… Peter couldn’t build a plane with fairly refined technologies… now he wants to build one with bleeding edge? I mean let’s all hope he survives and doesn’t bring more donors in, cause they’re not ever gonna get an actual reliable plane

[@DontWatchProductions]

Trying to make an electric airplane makes about as much sense as making a gas powered vibrator.

[@Argosh]

I just hope this is so unrealistic that he won't get it to a state where it can be airborn long enough to kill him...

[@anthonyhunt701]

E-Fan should have been built!

[@53jed]

If a ducted fan loses power at higher speeds why are all those airliners running turbofans? A turbofan is essentially a monster ducted fan strapped to a turbojet engine. They wuffle along at around 500kts. There are supersonic turbofans no>

[@rv6ejguy]

The jet thrust is substantial and the big stuff has many tens of thousands of hp. Blades are optimized for high speed and with the very high hp available plus jet thrust, they perform well enough on takeoff and low speed. The piston driven or piston/ electric hybids have low power, with low disc area and low fan solidarity. With low power, they can't be optimized for high speeds as the tradeoff down low would be even more dreadful performance. As shown by the examples here, they perform poorly compared to conventional propellers.

[@vitordelima]

@@rv6ejguy Still ducted propellers could work.

[@speedomars]

The Raptor will never get made...NEVER...this guy is selling snake oil. He crashes a plane that is basically a Velocity, then switches right away to some other goofy approach. Smell a problem here folks?

[@ToyManFlyer1100]

I think the dude should stick to what he knows best...Building nifty looking Corn Harvesting Equipment...Don't remember what the Wingspan was...He took outta buncha corn in one fell swope...John Deere and International Harvester would be proud 👏!!! 👏 🙌 😀 👍

[@SamIIs]

"It's all about all electric"...!!!

[@rv6ejguy]

All electric will go nowhere with current battery power densities. The 700 pound battery shown in my example is good for only about 10 minutes of flight in this case. Essentially useless except for emergency power.

[@SamIIs]

@@rv6ejguy That is true, but it is the future it's undeniable.

[@vitordelima]

@@SamIIs Above a certain horsepower rating (maybe around 500 to 800 hp or less) anything electric is still shit for aircraft.

[@RobertLBarnard]

I've just found your channel, so glad to find your analysis and appreciate your post. What are your thoughts about the line of 3 and 4 cylinder engines from Yamaha? We are seeing impressive performance for STOL drag competition s, especially given the power to weight ratios and fuel burn.

[@rv6ejguy]

They have excellent power to weight ratios and are well suited to the STOL environment, where high power is used for less than a minute in most cases. For traditional use, boring along in cruise for hours on end, I'd expect they'd have to be de-rated somewhat for longevity.

[@RobertLBarnard]

@@rv6ejguy Thank you. But I was really hoping to hear something like, "derated down to 200 hp, you can get 1000 hours before needing to rebuild one. so for nearly turbine power-to-weight ratio and modern 4-stroke fuel sippage on a home-builder's budge, the Yamaha's are the logical choice". Lol, I guess hope is forever in bloom. Someday we may have such an engine. Thank you again.

[@rv6ejguy]

@@RobertLBarnard Even 400 hours is a lot of flying for most of us and a good tradeoff. Rebuild costs would be pretty cheap by Lycoming standards.

[@cheerdiver]

Electricity is the most expensive form of power, as even modern generators are only 50% efficient. Commercial induction motors start at 95% eff, inv/control maybe 95% yet expect 90%. Even to dis/charge, is well over 90%, yet the production by an ambient temp generator will still be 50% efficient. ICEngines are around 20% approaching 25% w/ forced induction. Props are not 100% eff. Notice how the college team made the fan internal to the body, to avoid duct drag. Duct fans can yield a 10% gain over prop eff. IMO, synthetic fuels will result in smaller engines, and lighter fuel loads. And everything will start following the Celera 500 design.

[@vitordelima]

If you don't heavily tweak the engine (some diesel generators can reach 50% efficiency), the whole thing doesn't make any sense.

[@daveb4446]

Hybrid electric is the most efficient ICE system available. Have you never hear of a locomotive before?

[@cheerdiver]

@@daveb4446 Sorry, locomotives are efficient b/c they run steel wheels on a steel rail (.07 drag Coefficient). Electric motors are needed for the torque requirements. Basically inefficient transmissions.

[@briangill2804]

@@daveb4446 The reason locomotives are hybrids are because they have 8 driving wheels, and distributing several thousand HP mechanically would be a mess. Also, as hybrids, they get some free energy from regenerative braking. Not the same situation as airplanes.

[@nonsequitor]

Overall electrical efficiency 88%.... great...soooo net fuel efficiency what? 20%?

[@rv6ejguy]

Probably around 25% overall, depending a bit on IC engine used.

[@tantan4662]

Someone from Kleinvision made a flying car recently So take your research into innovation as supposed We await see if you really know 🤔

[@iforce2d]

What does that have to do with this video??

[@RealRickCox]

Personally... I think Peter needs to get help from someone who knows a think or two about building experimental aircraft. Maybe Mike Patey would be willing to offer up some advice for him? :)

[@rv6ejguy]

But would Peter take that advice? He didn't take any first time around because of his hubris.

[@gpaull2]

Patey is too smart to get involved in this soap opera…

[@murryrozansky8753]

Many people have drunk the "Electric Kool-Aid " or are or plan to profit from it.

[@creightonking8436]

Electric airplanes just take money from investors

[@codetech5598]

@@creightonking8436 Lilium?

[@kirkc9643]

No chance. Don't need to be any kind of engineer to know that it is not feasible.

[@colinmcewan9815]

Agree with most of this, however, isn't the thrust vs. speed for ducted fans that you show assuming constant fan RPM? This is a limitation of ICEs but much less so for electric motors. After all, turbofans are just turbine-powered ducted fans, and it's hard to argue they're less suited to high speed use than props are.

[@rv6ejguy]

Most turbofan engines develop thousands to tens of thousands of hp and these are optimized for cruise. We don't have that kind of hp available in the case of NG. Thrust shown in the chart is at maximum rpm the motors can turn the fans at. Fan thrust varies as the cube of the hp. As a result, there have been no high speed piston/ fan powered aircraft developed to date.

[@vitordelima]

@@rv6ejguy There is a kit airplane that looks like a fighter jet, it uses fans and a piston engine.

[@russellesimonetta3835]

No go!

[@hcraretep]

Why not just battery. Mold some solar cells in the skin to help charge.

[@gpaull2]

Yes, for the untapped market of people who want to fly for 30 minutes and recharge for 3 days.

[@wayneyd2]

Yes! They steal the idea and design from RWTH Aachen.

[@SooperToober]

FrankenRaptor NG