It's baack! The Raptor 2.0

3393RP said:
Not a problem. Peter says he can adapt software currently written for drone applications to manage VTOL operations, and the pilot won't have to learn or perform the control inputs necessary for hovering, transitioning to takeoff, and landing.
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oooooh, I'd love to see someone try to go to the FAA with re-used drone software for a safety of flight application.

Sure, let's mash some ol' drone software into a Level A application.

Weeeeeeeeeeeeeeeee
 
Bob Noel said:
oooooh, I'd love to see someone try to go to the FAA with re-used drone software for a safety of flight application.

Sure, let's mash some ol' drone software into a Level A application.

Weeeeeeeeeeeeeeeee
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Based on my observation of people here who think that their experience developing consumer applications gives them superior insight into to DAL A software development I'd say he's far from alone in his misunderstanding of flight-critical software design and testing processes.

Nauga,
whose margins have margins
 
John Myers said:
This seems to defy the laws of physics, like his other creation.

Is there a simple equation that relates power to thrust assuming 100% efficient power transfer? Seems like this could be quickly debunked mathematically.
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Well, work is force x distance.

So at his maximum stated speed of 300 knots (154m/s) on two of those engines you have 3000 lbs of thrust, which is 13340 Newtons.

So work per second is 154m x 13340 Newtons, which is 2054360 Joules.

Power is joules per second, so that's 2.05MW.

From two 67KW (90HP) thrusters.


It may not be quite that bad as I doubt the 300 knots figure is at sea level, but it's not far off.
 
Peter’s measurement of thrust is newters instead of newtons, which makes the math work out.
 
My back of the envelope calculation says that to get 1500# thrust from a 24" duct at zero airspeed (i.e. hover) takes 1222 HP assuming an impossible 100% efficiency, That's a bit more than 90HP.
 
I never followed those Raptor threads until now. My understanding of his current concept is that the two 90hp fans in the back with one in the nose constituted the 3x1500 lbs of thrust for VTOL.

You folks doing the math and physics show the ridiculous disconnect from reality that exists here. However, if he got rid of the also ridiculous 300 ktas, and VTOL concept,(and 4000MGW),(and 14ft wings since not enough lift for lower airspeeds), I wonder what kind of performance could be obtained with just the two 90hp in back. What kind of internal combustion electric generation in the rear would be required to power both of his fans? It would seem that the weight and balance would be way way off though and concentrated in the rear. The pictures are beautiful though, and perfect for flame wear.
 
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MajorTurbulence said:
However, if he got rid of the also ridiculous 300 ktas, and VTOL concept,(and 4000MGW), I wonder what kind of performance could be obtained with just the two 90hp in back.
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Well, the Tecnam 2006T has two 100HP engines, and it has a max cruise speed of 145 knots, so a bit less than that?

... but that's ignoring the extra 700lbs of empty weight and at least six extra square feet of fuselage frontal area that his next-gen raptor has.
 
Dana said:
My back of the envelope calculation says that to get 1500# thrust from a 24" duct at zero airspeed (i.e. hover) takes 1222 HP assuming an impossible 100% efficiency, That's a bit more than 90HP.
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Bah! The math isn't important when you have a vision! :)
 
I'm surprised Peter is not getting offer letters left and right from RR, GE, PW, etc for Chief Engineer, total comp packages into the seven figures

Rolls Royce claims their Trent XWB is the world's most efficient aero engine, their own site claims it puts out about 50,000 hp and generates about 75,000 lb thrust. Peter's diesel electric partial span ducted fan need just 0.06 hp per lb thrust vs RR's 0.67 hp per lb thrust. RR could improve their efficiency by a factor of more than 10 by simply using Peter's tech. Wow.

RR
50000 hp / 75000 thrust = 0.67 hp per lb thrust

PM
90 hp / 1500 thrust = 0.06 hp per lb thrust


Source: https://www.rolls-royce.com/product...pace/widebody/trent-xwb.aspx#section-overview
 
man.. Robinson could add another 700 lbs to their R22 max gross weight just by using one of Peter's ducted fans.
 
I didn't even catch which ducted fans he was using. Is there any data on them?
 
100% Peter designed fans. I question that his design can even run at 5000 rpm for 5 minutes let alone produce his claims. Lots of working parts for a “fan”. His prototype rattled and bounced around like a pin ball machine.
 
Lindberg said:
There's three of them.
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3 fans, 2 motors driving 2 generators to power the 3 electric fans. If I understood right. By the way, the motor doesn’t actually exist yet either….

His claims are so insane it’s not even worth pointing out the inefficiency of having both gas and electric motors.
 
Since the ducted fan came up.. here's a snap of it from the vid. The added arrows are mine. I can appreciate some of the "dyson" esq vision behind this, however this has a lot of nonconventional components. The biggest of which to me are the rollers to keep the fan assembly tracking. Each will require maintenance, lube, and introduce points of failure.. I count 22(?) of them

The other is the idea of driving this thing, I assume this is one large stator with the fans being technically the rotor. An interesting idea, but surely not necessarily a weight conscientious one?

I could actually maybe get behind this type of ducted fan if it weren't for the absurd hp to thrust claim and what I assume is a lot extra weight

upload_2023-3-6_13-12-29.png
 
Tantalum said:
The biggest of which to me are the rollers to keep the fan assembly tracking. Each will require maintenance, lube, and introduce points of failure.. I count 22(?) of them
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At 1500 lb thrust, each of those rollers/bearings will only see 70 lb of force. It looks like they're about 1/16 of the radius of the spool, so at 5000 rpm (did he give that figure somewhere? I can't recall) they'll be turning 80,000 rpm. I'm not double-checking my math for obvious reasons. But what could possibly go wrong with those numbers?

If memory serves, Mr. Muller comes to the world from a software background. People who write code often fall into the trap of finding some small thing they dislike about existing software, arrogantly thinking that they can make a better piece of software from scratch,* and being right often enough at a small scale that the positive feedback loop puts them high on the Dunning-Kruger peak for all other pursuits. Compared with programming, aerospace provides a more complicated, less predictable,** and less forgiving*** environment to navigate down from the peak to the trough.

* Thus the proliferation of "exciting" and "unique" programming languages and software libraries that scratch one person's itch but crash as soon as they see inputs that their author was too narrowly focused to consider.

** If you write a 5-line function and test it against a range of inputs, you can generally trust that it will work the same when you put it into a 25-million-line project. If you design a 5-inch rudder and test it anywhere, you cannot trust that it will work the same when you put it on even a 250-inch airframe.

*** For all but the lowest-level programmers these days, the worst-case scenario in unit testing is that you instantaneously get a core dump that shows you where and generally why your program crashed. Two minutes later, you're unit testing a fix. For airframe testing, even the best-case failures take a long time to adjust and re-test, with a worst case time measured in lifetimes, namely that of the departed test pilot.
 
iamtheari said:
People who write code often fall into the trap of finding some small thing they dislike about existing software, arrogantly thinking that they can make a better piece of software from scratch,* and being right often enough at a small scale that the positive feedback loop puts them high on the Dunning-Kruger peak for all other pursuits
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wow, very well put!
 
People who write code often fall into the trap of thinking they have tested all possible inputs.
 
iamtheari said:
If memory serves, Mr. Muller comes to the world from a software background. People who write code often fall into the trap of finding some small thing they dislike about existing software, arrogantly thinking that they can make a better piece of software from scratch,* and being right often enough at a small scale that the positive feedback loop puts them high on the Dunning-Kruger peak for all other pursuits.
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That's called the Andy Grove fallacy, when applied to the life sciences. https://www.science.org/content/blog-post/andy-grove-rich-famous-smart-and-wrong

Silicon Valley (wherever the practitioners might actually be located) has had some spectacular failures when they step in to 'solve' biopharma problems, thinking that whatever they've been doing so successfully in their industry will apply just as well to the problem of drug discovery. Doesn't work that way. In tech, one has the advantage of both the hardware and the software being designed by humans, so it's all pretty well understood. Not so much when dealing with biological systems, which not only weren't designed by us, but usually are only understood at a fairly high level. Get a little further down in the weeds, and biology is a weird, wild, wacky world that does NOT behave the way we want it to or think it should.
 
Salty said:
People who suck at programming maybe.
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there is huge chasm between the people who can write excellent code and the people who know how to test. Different skills.
 
Bob Noel said:
there is huge chasm between the people who can write excellent code and the people who know how to test. Different skills.
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Knowing how to test is a completely different thing from “thinking they have tested all possible inputs”.
 
DaleB said:
I think he’s either completely lost his marbles or has decided to move on to simply making a living by finding gullible suckers and taking their money. It’s moved from “impractical dream” to “utter nonsense”.
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Yeah, he's gone from making something that is sortof flyable to straight out Florida Con-man....
Didn't that guy who was trying to make flying cars for years finally cash in by selling to a Chinese company? Maybe he's going that route.
 
I may be misremembering...I though he handed off the project to another group. Wasn't that where he was headed with Raptor 1 when it went down?
 
I think the depth of the bulls*** has reached the level where it obscures not only the answers, but the questions themselves.
 
Why doesn't the most hated airplane builder just say it's a space plane!
 
3393RP said:
A minor correction: kW rather than kV.

They're way behind Peter. He's producing 1,500 lbs of thrust with 67 kW.

:D
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Not only that, he's got them beat with a fan that's a full 8" smaller! It's amazing!





Or at least delusional. :p
 
It's nice to see the advancement, but not even the DARPA fan could lift an Ercoupe for VTOL. You'd need three of them. Very cool tech though!! And it really puts PM's claims into perspective.
 
You want to believe in him and his innovation, but he’s such an arrogant and condescending lad that it’s hard to.


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Llk said:
You want to believe in him and his innovation, but he’s such an arrogant and condescending lad that it’s hard to.


Sent from my iPhone using Tapatalk
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It might be easier to overlook the arrogance and condescension, if his math wasn't so blindingly wrong and his engineering skills so lacking.
 
At present I'm just trying to understand what innovation he's proposing. EDF's have been successful in model aircraft for many years but they don't scale into full-size planes (yet). If he's just going to run a couple generators to run the EDFs, why not just attach the 'generators' to propellers?

It just seems like his innovations are answers in search of problems.
 
3393RP said:
Yes, folks, the Raptor is back. The black magic ducted fans will propel it to 300 knots on 10-11 GPH. It does VTOL too!

Range: California to Hawaii on 80 gallons of fuel. You don't need to watch all 34 minutes, the surprises miracles are revealed in the first 9.


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Edit: I did the calculations on claimed static thrust vs. power required for producing that thrust vs. fuel consumption to make that power (especially with "a couple of small generator motors", which certainly won't have a BSFC any better than what we have now, despite mfg claims.)
The results would require Moller-esque manipulation to get close to the claims.
 
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Salty said:
People who suck at programming maybe.
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All software sucks - consumer and "business" grade applications are "80 percent" efforts - they work fine for most scenarios, most of the time, mostly with klunky navigation. If an ERP or sales or phone app can't handle a particular and less-likely event gracefully the vendors don't much care unless the push back is significant.

But 80 percent isn't so hot for physical world purposes - I'm not gonna be happy if my car fails to start one random morning each week. i don't remember the source, but seems like I recall the astronomical cost per line of code for the original space shuttle software getting man rated - I think the computers were essentially flight hardened IBM 360s? Or at least based on the 360 architecture.
 
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