Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

JetZero

jetzero.aero

Post reply on HN
Print view View original

231–240 of 277 posts

Re: JetZero

#231

Post by cassepipe »

mlrtime wrote: post #187
cassepipe wrote: post #183

I love how the last image of the landing page is a model of the most efficient plane ever designed on a pole attached to what may be the least efficient vehicle ever made, the infamous US tax-loophole-pick-up truck

You mean the infamous best selling truck of all time globally? The vehicle that actual working people use everyday? Just because you see a few people use them not for work doesn't really mean anything.

And your point is... ?

Just because some people go to work in inefficient and dangerous-to-others cars does not make them more efficient. I am working a construction job, does this mean I should not think about what I am doing ?

Re: JetZero

#232

Post by ctippett »

SubMachineGhost wrote: post #74
syntaxing wrote: post #70

Fluid dynamics is my jam (most of my masters was studying it)! Even in the intro to fluid mechanics book, they spent a good half+ chapter why a flying wing is superior and how you can have it designed similar to movie theater seating. But my professor spent a class explaining why regulation will kill it even though the design is great.

Can you share more on why regulations will kill it please?

The regulations currently require all passenger aircraft to be able to maintain positive static stability, which is inherently at odds with the aerodynamics of an all-wing design. As technology and test-flights demonstrate that these designs are actually feasible (and safe), I expect the regulations will eventually be updated.

Re: JetZero

#233

Post by gertrunde »

iamwil wrote: post #103

What I really want, is a plane that can load passengers like containers--or like a rollercoaster car. Of course, it should be comfortable. I just mean that the passenger compartment should be modular. So you can put your luggage in and get settled while sitting in the airport, and then when the plane comes in, it just side-loads everyone all at once. Once landed, it just slides everyone off, and you can just I know t…

Those kinds of designs have been proposed before iirc, mostly with a large section of the fuselage that drops in/out.

There's Airbus's US patent US9193460B2 if you fancy a comedy read!

Re: JetZero

#234

Post by ungreased0675 »

When looking at potentially revolutionary technology companies, I tend to evaluate more harshly than I would with normal companies.

Three things on the JetZero website trip my BS detector. First, it appears they’re developing their own avionics displays/interface? That’s a terrible idea, they need to be laser focused on one core task.

Second is this quote: “The Pathfinder team has built and flown five generations of scaled aircraft over 30 flights. The most recent flights validate both the configuration and control laws of our full-size Jet1 Demonstrator.“

Over 30 flights seems really low. They should be testing way more than that, no?

Third, I spy a full-scale interior mock-up. There isn’t even a working prototype, but they’re paying people to pick out carpet colors?

I really want this to succeed, but it doesn’t look like these are serious people.

Re: JetZero

#235

Post by kelnos »

bruce511 wrote: post #118
noduerme wrote: post #95

Earlier quoted context omitted.

I've been that guy, but only if the scenery is interesting. Still, my attitude is that at noon, people don't need to have a blanket placed over their cage like parrots to make them sleep. I also was on a flight once that had a very bouncy landing with all the windows down - when I didn't realize we were anywhere near the ground yet. I'm not into tuning out reality to that degree, and don't really feel obligated to he…

Regulations require that window shades be up (open) during take off and landing. I was sitting next to a passenger once who was asked by the steward to raise the window shade. While doing it, they asked "why". Answering for the steward I said "it's so Fire and Rescue can see into the plane if we crash". (Which is true, I used to work at airport fire and rescue.) The steward looked at me with a "that's not helpful" lo…

> The steward looked at me with a "that's not helpful" look.

I get that they don't want people to panic, but I think an attitude of coddling people like that isn't productive.

Re: JetZero

#236

Post by kelnos »

cassepipe wrote: post #184
conorcleary wrote: post #182

Earlier quoted context omitted.

If the design is more efficient, then eventually the fuel you put into it can be replaced by your magic solution.

Except there is another issue, how many people do you fit in this shape ? If you can only fly 30 people that's not very efficient as it would mean more flights. Also I believe the further away you are from the rotation axis of the plane where it turns left or right, the more unpleasant your flight may be

The website says it can seat 250.

Re: JetZero

#237

Post by kelnos »

carabiner wrote: post #163
calmbonsai wrote: post #145

Earlier quoted context omitted.

I don't see how having a marginal amount of single-engine aviation flight experience is relevant to Dunning-Kruger. If anything, it's taught me how little I know about "real flying" compared to CFD and systems engineering. Commercial aviation is conservative because aviation is "hard" and mistakes in aviation are "extremely costly".

It's a lot like saying, "as someone 5 hours into driver's ed in my mom's honda civic, I believe that future stability control algorithms in self-driving cars..." Or the difference between a (noob) software user and a software engineer.

No, it's not. They're saying "as someone with a small amount of insider experience, even I can see how everything is super conservative and no one wants to innovate".

Re: JetZero

#238

Post by jmward01 »

eightysixfour wrote: post #48
jmward01 wrote: post #33

I wish them all the luck in the world. Aviation is in a massive rut and needs bold new designs and innovation. That being said, what makes this company different from the others that have come before? What makes their path to success more likely? The problem is likely less the technology and more the decade(s?) of burning money with no ability to sell anything because you have to certify everything. That cliff is so…

> Aviation is in a massive rut and needs bold new designs and innovation. Why does it need bold new design and innovation? More people (can afford to) fly every year, more safely, and with broadly more consistency than they ever have. The success of the commercial aviation industry as a whole is breathtaking.

The 737 max is a great example of the rut we are in. In order to put more efficient engines on they needed more ground clearance. This has been the issue with 737 forever and why they have that odd flat scoop on the bottom of the engines. That isn't great for efficiency. It is because they can't redesign the wing without years long recertification. So, yet again, instead of redesigning the airframe to optimally place the engines they pushed them forward impacting the cg of the aircraft and requiring them to hack systems into the aircraft that countered for the reduced forward cg. Then, because they again didn't want to go through the recertification nightmare, they claimed no new training on the aircraft was needed. This led to pilots not knowing how to handle when the systems added failed. The root cause of the hacky design and missing training was avoiding a years long certification process that would have made it cost prohibitive to create an aircraft with more efficient engines. This is a minor change compared to building in really innovative new features.

To your argument of (paraphrase here) 'it is good enough why innovate'. I flat out reject that argument. Horse and buggy were good enough. The telegraph was good enough. We only needed 1 mb of memory because it was good enough. We are missing so much right now. We potentially could have small, efficient, point to point air taxi service for the average person, completely dismantling the massive, and horrible to deal with for people, hub and spoke system. Travel could get so much better and cheaper, but instead we have the 737 max. An incremental change on a decades old design because real innovation is lacking in the industry.

Re: JetZero

#239

Post by JumpCrisscross »

amluto wrote: post #164
JumpCrisscross wrote: post #162

Earlier quoted context omitted.

Coördination stops lateral passenger movement. It does nothing for up and down. (Coördination is also about more than comfort. It keeps the flow attached to the wing. If your passengers are slipping, so is your wing.) In a roll, with a tubular fuselage, everyone—pilot and passengers—feel about the same vertical Gs. OP’s point is in a flying wing, the folks on the tips will lift up or drop down relative to the pilot a…

> Specify a maximum roll rate in training and normal-law software and this problem is solved I’m wondering whether there are major airfields with traffic patterns that require roll rates that would exceed whatever maximum is desired for comfort. My intuition is that the situation would be tolerable at most airfields but that normal-law limits that are too restrictive could be dangerous.

> major airfields with traffic patterns that require roll rates

One, this is where the more lifting body turning faster with less roll kicks in. Two, I suspect those airfields would also be the last ones to add terminals that can dock with a non-standard plane.

Post reply on HN