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Larry Page’s startups working on flying cars

bloomberg.com

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Re: Larry Page’s startups working on flying cars

#191

Post by parfe »

6stringmerc wrote: post #173
parfe wrote: post #163

Earlier quoted context omitted.

I just flew on an a320 and watched the plane taxi to the gate. Someone on the ground crew in an orange vest walked around the plane and did a visual inspection using a flashlight. At no point did someone from the flight crew leave the plane.

Curious as to what airline and at what airport? Usually pre-flight is before the plane taxis "from" the gate not when it arrives "at" the gate.

Are you referring to only the first flight of the day?

A plane lands, taxis to the gate. Passengers disembark, the plane gets cleaned and refueled, people on the ground checked it out, new passengers board (me), and it taxis from the gate. At no point did the pilots leave the airplane to "walk-around".

Re: Larry Page’s startups working on flying cars

#192

Post by marvin »

uncoder0 wrote: post #175
6stringmerc wrote: post #160

Earlier quoted context omitted.

No, they do work just fine with Jet-A. Are they practical? No. Will electric battery technology overcome the constraints within 5 years? That's a viable hypothesis, sure.

I don't think battery technology could overcome the specific energy constraints in 5 years... Seems highly unlikely. Jet-A is 46 MJ/kg - Lithium Air ~40MJ/kg - Lithium Ion is 0.85MJ/kg Lithium Air is the only thing remotely feasible that 'functions' in a laboratory and it has not left the lab since 1970. "Another recent review on Li-O2 batteries, authored by materials scientists from Technion- Israel Institute of Tec…

It wouldn't be an entirely apples-to-apples comparison to jet fuel. A fully-electric VTOL aircraft would ditch most of the wings, for instance, and instead make the fuselage lifting-body.

Wings are large to provide enough lift at takeoff and landing speeds, tail and rudders to provide aerodynamic stability which would be provided by electric motors instead. Also, the engines would be lighter and a significant fraction of the empty weight would be batteries. We wouldn't see an electric drop-in replacement for a long-distance airliner in the near future, no one is claiming that.

Re: Larry Page’s startups working on flying cars

#193

Post by jfoutz »

handedness wrote: post #130
outworlder wrote: post #102

Earlier quoted context omitted.

> Preflight checks and flight safety. Larry should first build normal small aircraft that can do without constant manual checks before flight. Omg, this. The amount of checks required for any sort of aircraft is ridiculous. A lot of it involves button pushing and checking status. This could be automated. For instance, for a cessna 150: STARTING ENGINE Mixture – RICH Carb heat – COLD Prime – AS REQUIRED Master switch…

The examples you gave take no more than 30 seconds. Sure, FADEC can eliminate most of them, but they're quick. Other examples–checking the oil, the tank sumps, the intake, the tires, the flap tracks, the rudder bolt(s), the wing tips, the tailwheel springs, etc.–are the stuff that software largely can't replace, and are the more time-consuming part of taking off. Put another way, the latest fighter jets and commercia…

Could cameras at various points of the plane could identify when things are not perfect? Computer vision has limits, but identifying leaks, ripples on a surface that should be smooth, and rivet discoloration seem pretty feasible. Granted, I'm not a pilot, and i've never done a walk around.

I can't figure out how you'd check the tips of the wings, but the leading edges should be visible from up by the nose. Similarly, the trailing edges from the tail.

It's also easy to be extra cautious. bias to 0 false positives. Sure it will detect problems that turn out to be dirt or poor lighting or something, but one visual check seems faster than 20 (or however many are necessary).

in a controlled environment like that, you could require stuff to be painted computer vision friendly colors. Even more, i'd bet oil reflects differently than metal under different lighting. internal stuff could be lit up with IR or some other part of the spectrum for easy detection.

I dunno. seems like perhaps a few pounds of electronics.

Re: Larry Page’s startups working on flying cars

#194

Post by PhasmaFelis »

marvin wrote: post #142

This thread has the potential to become hilariously cringeworthy in a decade or so. I'll be checking back in five years to see if lightweight VTOL aircraft are still an idea that is "obviously stupid because we've tried it before and it didn't work". My guess is that the progress in batteries and electric motors will have made this concept a lot more feasible by then. At some point it will be a completely obvious ide…

The problem isn't the tech. There have been flying cars--as in, vehicles that are both road- and airworthy--for more than half a century. The problem is the logistics and practicalities.

Re: Larry Page’s startups working on flying cars

#195

Post by cpncrunch »

TeMPOraL wrote: post #182
skj wrote: post #166

Earlier quoted context omitted.

What happens when a car veers off the road into your living room?

Probably much less damage, because a typical car in the city is going much slower than a typical plane falling from the sky, and kinetic energy goes with square of velocity...

A plane (with BRS parachute) falls at 10-20mph, according to BRS's website. Typically a small plane will weigh about 2000-3000lb.

A car in the city will be going at about 30mph, and will weigh about 4000lb.

There are news stories here regularly of cars driving into storefronts. Generally when I hear a story about a Cirrus activating their parachute, it lands on empty space and doesn't do any damage.

Re: Larry Page’s startups working on flying cars

#196

Post by marssaxman »

Nav_Panel wrote: post #104
marssaxman wrote: post #80

Earlier quoted context omitted.

Wait, now - you want to exacerbate sprawl and worsen suburban inefficiency, and this is supposed to be a benefit? I think you have just convinced me that personal flying vehicles are a terrible idea to be opposed at all costs.

I'm not saying this view is a positive thing, it's merely what I imagine will happen if personal flying vehicles become affordable, based on past trends and our political environment. I would personally prefer more investment in public transit and dense urbanity, which isn't even really possible due to overly restrictive zoning laws.

Ah, sounds like we are much in agreement then.

Re: Larry Page’s startups working on flying cars

#197

Post by stcredzero »

TeMPOraL wrote: post #183
stcredzero wrote: post #181

Earlier quoted context omitted.

No matter how energy efficient the engines are, hovering and short takeoffs use lots of energy. What about electric vehicles with beamed power? The "heavy lifting" for a small electric aircraft could be done at the airport using beamed power, freeing up weight and increasing the effective range of the aircraft.

The question is, how much power would be needed. It screams "military-grade futuristic microwave weapon" to me.

LASER!

Re: Larry Page’s startups working on flying cars

#198

Post by robotresearcher »

6stringmerc wrote: post #155
tim333 wrote: post #149

Earlier quoted context omitted.

We have machine operated lifts and trains, almost self driving cars, aircraft autopilots and having witnessed my own efforts at flying a plane I think a computer could quite likely do a safer job.

Oh really? Because there's a bunch of Air France wreckage just North of South America regarding a computer fuck-up that wasn't properly ajudicated by the pilots in command, which would have saved the passengers (as it had in other instances where the pilots saved the plane). That's just a high-profile one by pilots who were easily more qualified than you or I to be in charge of a major airliner. http://www.ntsb.gov/i…

And 400,000 Americans dead in traffic accidents in the last 20 years. All happily driven by humans.

Re: Larry Page’s startups working on flying cars

#199

Post by robotresearcher »

EA wrote: post #30
rtpg wrote: post #15

What problems do flying cars solve? I know it looks cool but is there some huge thing that would get solved with this?

I work around dozens of pilots. Most of them used to own, co-own, share, or lease a plane. Only a few of them actually have a plane they could go fly right now. Maintenance, upkeep, costs, and regulations are obvious reasons why some would be deterred from owning and using a private plane. But most everyone of the pilots said, if you want to go to the beach, in general, the best way to get there is a 6 to 8-hour driv…

Float plane. Tie up at your dock.
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