Basic Configuration for a "Safe" airplane

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Hot Wings

Grumpy Cynic
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I think the # of orders of magnitude easier is somewhere in the neighborhood of 0.2.
I come at this from the other side - the DARPA autonomous jeep project. Compared to that challenge drones were considered little more than 3D Rumbas by the teams. I'm not trying to trivialize the task of creating a safe man rated autonomous aircraft but there are a lot more impromptu variables for a ground bound vehicle to process.
The Uber car that killed Elaine Herzberg failed the the most basic task of a self driving car - don't run over something in front of, or on a collision course with you. Going from that to a car that can tell the difference between a little water running across the road and a flash food wash out is going to take a while.
 

BBerson

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One overly simple example within the air show industry: a reverse half Cuban from upright is much less likely to result in hitting the ground than is a reverse half Cuban. The viewing public really doesn’t recognize the difference
The half reverse Cuban eight was the first entry level maneuver in AMA RC competition. It starts with an "uphill" climb. Botched maneuvers generally go "downhill" rapidly.
 

Marc Zeitlin

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I'm not trying to trivialize the task of creating a safe man rated autonomous aircraft but there are a lot more impromptu variables for a ground bound vehicle to process.
Many of the folks I worked with had worked on autonomous cars, drones and submarines.

While our original thought was that "hey - we're in the air - don't hit the mountains and don't hit the other planes or birds" was going to be good enough. Until we started thinking about the fact that the plane still needs to be able to do EVERYTHING that a car can do in order to get from the parking spot to the runway - don't hit the moose, don't drive through potholes, don't hit the gas pumps, don't get fooled by the rain, snow, or fog, don't run into other airplanes or buildings, even with the wingtip that's who knows how far away from the CG of the aircraft, don't take off if there's a flock of birds flying around the runway, etc.

So I agree that the car is probably more complex, and there are almost certainly more corner cases and issues, but the plane still needs to drive slowly on the ground in areas that may or may not be more controlled than roads (think uncontrolled, unfenced airports), and do it from 0 mph to takeoff speeds. THEN worry about not hitting crap in the air. Once you start digging into actual operations, it gets a lot more complex than one would think at first - certainly how complex WE thought it was going to be at first.

The airplane also needs to operate in the NAS, so needs to be able to communicate with ATC in a bidirectional way, so it not only needs to announce what it's doing, but it also needs to ingest ATC instructions and acknowledge/respond appropriately. Right now, with the existing NAS, that can only be done via voice control. Cars do not need to do that, as there is no GTC. Would you want Alexa being your interface to ATC? What's Alexa/Google/Siri's success rate at understanding you when you ask a question? 80%? 90%? Good enough to fly a plane? Hell no.
 

Dan Thomas

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Even just a study of the Five Hazardous Attitudes can wake the serious student up to the things that could get him. There are resources on the 'net for that, including self-tests to find which of those attitudes apply to you. And we ALL suffer from one or more to some degree. I remember our students' reactions after taking that test and seeing the results: "That's not me!" they'd say. "It sure is," the others would say. We don't see our faults as clearly as others do.

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https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/04_phak_ch2.pdf
 

Bigshu

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Two things come to mind:
First there's a lot of handwringing over GA accidents, but only because we fear the new regs from the FAA to address the "problem", when the problem is an inattentive or reckless pilot. How many accidents, fatal or not, are we talking about? The Nall report says 111, with 23 fatalities. We have that many car crashes in less than an hour nationwide (just making a point, I don't know that stat for real). So, the problem really isn't the number of accidents, it's that we are under the thumb of an agency that kills us with regulations trying to get to zero failures in a system that relies totally on human control. Everyone knows the only way to zero in that system is to legislate or engineer away the source of the problem, which is GA.
Second, since LOC on landing and takeoffs is the source of so many accidents, Why aren't we working more on VTOL aircraft, that makes those phases of flight slower and less affected by things like 50 foot obstacles, or short runways, or density altitude? Just asking!
 

Victor Bravo

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If large "major national infrastructure" networks have been successfully hacked, how is an airplane that is connected to any data network going to be made secure enough to not fall victim?

I looked at the Merlin website and saw they claim to have autonomous control from inside the airplane, not somebody in a room on another continent. That's just great, and inside the airplane software may be more resistant to hacking than a remote control system. But what about all the external sources of data being provided to that onboard system? Weather, altimeter setting, traffic instructions, commands from ATC, navigation, etc. etc. etc. What about the ethernet cable or thumb drive or bluetooth or microwave connection that someone loads into the aircraft to tell it what to do and where to go before the flight?

BTW MZ, the photo of you standing next to your airplane is PC-fabulous... to quote the late, great Buford T. Justice... "ooh, pardon me... you sounded a little taller on the radio" :)
 
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PMD

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Pilot training.

The single largest cause of aviation accidents in genav is "controlled flight into terrain," followed, I believe, by fueling errors. Neither of those are resolved by changing the airplane.
Not so. By increasing fuel supply to be longer duration than bladder capacity, fueling errors can easily be avoided. The required fuel quantity to do so decreases linearly with age (of the pilot, not the airplane). The latter is nature's way of contributing to flight safety.
 

Pilot-34

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Or, just make the gauges big enough to see, and don't bury them at the bottom of the panel. I always thought the pillar mount auto gauges were a great idea. Bigger faces, and always in your field of view. Never could figure why that hasn't been done in airplanes.
Fuel gauges should become more red and brighter red as they close in on empty.
 

Pilot-34

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All decent EMS systems have fuel warnings - my Dynon Skyview yells at me to switch tanks every time I burn 10 gallons, and it gives a yellow warning at 6 gal/side, and a red warning at 4 gal/side (all user configurable #'s). If I run out of fuel, I'll have earned it.
I’ve never heard of anyone running out of fuel with 4 gallons left.

It’s always that last teaspoon that gets you.

Honestly I think knowing that I had 4 gallons left in the tank which is nearly an hour in a lot of our planes Would actually be a detriment. “Well I’ve got almost an hour I can skip this one hour long fuel stop And slip into homebase.
 

Hot Wings

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Cars do not need to do that,
.......yet.

Hadn't considered the ground/taxi phase.
I'm guessing that if autonomous aircraft become the norm the verbal link will be replaced with a standard digital based one? We could probably use such a system for human piloted aircraft.
 

Pilot-34

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I'm a fuel sissy. I usually land with at least 5-6 gal in each tank mainly because my fuel gages are older than dirt and I don't trust them.
Healthy attitude.
I have been told that the reason airplane fuel gauges are so inaccurate is because they are simply old car gauges.
Should we fly planes from the 50s with fuel technology from the 30s…..
 

BJC

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Should we fly planes from the 50s with fuel technology from the 30s…..
I fly with fuel gauges plus a fuel flow totalizer that is very accurate.

When in CC flight, every 15 minutes, I do a mental cross check of fuel consumption, fuel quantity, distance covered, distance to go to the next airport, fuel required to get to the next airport. I also plan on landing with at least an hour's worth of fuel. If flying locally, I plan on landing with at least 30 minutes of fuel. I state my calculations out loud, and, if flying high (for me that is above 8,500 feet MSL) I have difficulty with the mental calculations, I will reduce altitude.

Simple rules, faithfully followed, can add significant safety to flight.


BJC
 

Marc Zeitlin

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... What about the ethernet cable or thumb drive or bluetooth or microwave connection that someone loads into the aircraft to tell it what to do and where to go before the flight?
All valid concerns that will eventually need to be addressed, just like in cars (Teslas automatically update themselves, I believe, for Cthulhu's sake), or in current EFIS/Navigation equipment into which one loads data each 28 days with an SD card or thumb drive.

BTW MZ, the photo of you standing next to your airplane is PC-fabulous... to quote the late, great Buford T. Justice... "ooh, pardon me... you sounded a little taller on the radio" :)
I don't know what photo you're referring to - there's no picture of me on the Marlin website. If you're referring to the picture next to the "Keeping Our Priorities Straight" on the "About" page, that's LB, the electrical technician and soon to be A&P, and the plane is N40CZ, not my plane, which is N83MZ.

No cigar for you :).
 

Marc Zeitlin

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Hadn't considered the ground/taxi phase.
Neither did we, until someone said "Hey - how is this thing going to get to the runway threshold?"

I'm guessing that if autonomous aircraft become the norm the verbal link will be replaced with a standard digital based one? We could probably use such a system for human piloted aircraft.
A digital system with visual display of ATC requests would work for both human and autonomous systems, and probably be way better than what we've got now, particularly since the messages could be individual and not broadcast on shared channels.

But given how long it took for the FAA to do a miserable job of implementing both ADS-B and the grand infrastructure upgrade that started when - in the 80's/90's? I wouldn't expect a switch to anything other than human beings talking on shared radio channels for another 20 - 40 years at the earliest. Which implies Natural Language Processing for ATC COMS for Autonomous Vehicles, and since NLP is by nature non-deterministic and the FAA has never (yet) approved a non-deterministic system (for what should be fairly obvious reasons - no one knows WTF they're going to do, for sure) I would not be holding my breath for approval of a fully autonomous aircraft in my lifetime, and I'm 64.

Now, Garmin has already proven that autonomous systems can be used for emergency backup (see all of their "Autonomi" stuff), but moving from "hey, the pilot's died - can we save these folks lives here"? to "George, take us to SLC" is orders of magnitude (and not 0.2 orders - multiple integers) harder from a technical, communication and regulatory standpoint.

No one here should be worried about losing the ability to fly their own aircraft due to autonomous aircraft taking over the airways within their children's lifetimes.
 

patrickrio

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Neither did we, until someone said "Hey - how is this thing going to get to the runway threshold?"
Runway should still be much easier. The reason is that you can much more easily build sensors and automated control into the runways and taxiways. This is too expensive to do on roads, but a minor bump in price for an airport. You have very finite distances to travel with very defined destinations and paths. Every vehicle is well defined in local processing and all vehicles are required to have standardized location devices on their corners so their exact location, speed and direction are known by local processing at all times. People are only authorized onto tarmac if also appropriately beaconed for direction and location. any detected deviation that is not solvable results in all stop for everything but immediately time critical safety operations.

Once landed the airplane would mostly become a dumb robot and it would be centrally controlled with local airport processing along with all other vehicles operating anywhere on the tarmac. The airport would look more like an automated Amazon Warehouse or a modern robotic factory or the subway in Singapore than a public road with Teslas, random vehicles, kids playing ball, random wildlife and fallen tree branches on it.
 
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Dan Thomas

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I fly with fuel gauges plus a fuel flow totalizer that is very accurate.

When in CC flight, every 15 minutes, I do a mental cross check of fuel consumption, fuel quantity, distance covered, distance to go to the next airport, fuel required to get to the next airport. I also plan on landing with at least an hour's worth of fuel. If flying locally, I plan on landing with at least 30 minutes of fuel. I state my calculations out loud, and, if flying high (for me that is above 8,500 feet MSL) I have difficulty with the mental calculations, I will reduce altitude.

Simple rules, faithfully followed, can add significant safety to flight.


BJC
Seems to me that the majority of pilots live where the majority of the people do: in big cities. They drive their cars there, too, and a gas station is never far away. They don't think about how far it is to the next fuel stop. Then they learn to fly, and that carefree attitude toward fuel is carried forward and they don't want to have to think about fuel planning. Some of them run out of fuel.

Out here in most of Canada's vast landmass we MUST be thinking about fuel when driving across country, which we do a lot. Lots of country to cross. Canada is bigger than the US and has 1/9th of the people. In many places there will be signs when leaving a community warning that the next fuel stop is XX kilometers away to get less astute drivers to think about how much they have and how far it will go. Tourists from the bigger cities tend to make such mistakes.

Fuel gauges are not trustworthy. Partly because most airplanes are old, they used old technology, that stuff is often worn out and the owners are too cheap to fix it, and because aircraft fuel tanks are usually in the wings where they have to be long and wide and flat-bottomed and very shallow, completely unlike a car or truck's tank. The wing's dihedral means that the sender can't be placed in the middle of the tank where the fuel level change due to attitude changes is minimal. It has to be inboard so as to measure the fuel as it gets low, since that's where minimum fuel---the most crucial fuel---will be. That means that the sender float is at its upper limit for a long time before the fuel level drops far enough that the fuel at the inboard end is falling. Stuff like this makes it really hard to design an accurate system without making the airplane a lot more expensive, as if they weren't already expensive enough. Large airplanes use multiple senders spread across the wing tanks, with their outputs summed to get a much more accurate reading.

We have choices. We can afford old airplanes that have these drawbacks and we can learn to think and calculate and be smart, or we can wait until we are rich enough to buy a new airplane with fancier systems so that we don't have to think so much. How many of you will wait, in futility, the rest of your life for that wealth just to save you the work of learning?

Facts. Some people don't like the facts. They go through life condemning all the stuff that they see as bad, and sit back and do nothing. Others face the facts and get on with the work and enjoy the stuff we have instead of waiting for the magic stuff that might never appear.
 

BJC

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Facts. Some people don't like the facts. They go through life condemning all the stuff that they see as bad, and sit back and do nothing. Others face the facts and get on with the work and enjoy the stuff we have instead of waiting for the magic stuff that might never appear.
Anyone who really wants to fly should get an ultralight or an airplane or join a flying club or find an airplane for rent ASAP, and start flying. Opportunities for enjoying sport aviation will never be better than today.


BJC
 
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