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Launch HN: Airhart Aeronautics (YC S22) – A modern personal airplane

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Re: Launch HN: Airhart Aeronautics (YC S22) – A modern personal airplane

#231

Post by echoangle »

the__alchemist wrote: post #223
TylerE wrote: post #206

Earlier quoted context omitted.

Stall speed is a misnomer. Stalls occur due to exceeding the critical angle of attack and can happen at ANY speed.

Whoever is downvoting this: Stop. It's the key point here. Planes don't need to know their weight to produce a stall warning; AoA is a great metric, and GA planes not having an indicator or warning based on it is astonishing.

I thought the point was predicting a stall by knowing the approach speed will be so low that you will stall, not detecting a stall just before it happens

Re: Launch HN: Airhart Aeronautics (YC S22) – A modern personal airplane

#233

Post by n_ermosh »

mhb wrote: post #229

In the demo, on what is the system's assumption that you want to land based?

a combination of altitude, commanded descent rate, and commanded airspeed transition the control system from flight to landing, flare and touch down, and into ground control mode.

Re: Launch HN: Airhart Aeronautics (YC S22) – A modern personal airplane

#234

Post by AdrianB1 »

echoangle wrote: post #228
AdrianB1 wrote: post #207

Earlier quoted context omitted.

Hard to tell. I have a frequent route that takes me ~ 2 hours of flight (13 liters/hour, 26 liters in total) or ~ 10 hours to drive with around 50 liters of gas. Flying means burning 50% less gas. But for others there may be better driving, how to calculate that?

What kind of plane are we talking about here? A Cessna 172 is cruising at about 200 km/h, so your route would be 400 km. You’re not driving 10h for that, right?

560 km, almost no highways, a lot of driving through the mountains at 50-60 km/h. Flying is an almost straight line of 320 km. Ikarus C42, cruising 160 km/h.

Re: Launch HN: Airhart Aeronautics (YC S22) – A modern personal airplane

#236

Post by danielschonfeld »

aeternum wrote: post #165
sethkim wrote: post #83

Instrument-rated pilot (and engineer) here. First - congrats on the launch! I think you're working on an interesting set of components that will prove useful to GA aircraft technology. Bringing fly-by-wire, and lowering the cost of maintenance/manufacturing are both great efforts. That being said, my personal view is that stick-and-rudder control is one of the less critical components to improving GA safety. Everythi…

Excellent points, it's really these other aspects that get pilots into trouble. For example it's crazy that most pilots are still taught to calculate W&B using printed charts and approximate takeoff performance. I think you could save more general aviation lives with a fairly minimal system. A gas gauge sensor that calculates whether you have enough fuel to get to your destination + reserve. Avionics where you input…

While some base to final stall accidents are as simple as you make it sound a good chunk of them happen when you try to come OUT of the turn at an already slow speed increasing the angle of attack on one wing alone. The stall and subsequent spin catches the pilot entirely surprised unaware of why they’re even stalling and with very little escape bandwidth.

The FAA has been trying for better angle of attack instrumentation but what I described above isn’t an easy fix with technology.

When you talk to pilots who inadvertently stall spin and lived to tell the tale most of them will tell you they didn’t even recognize that they were in a stall. That’s where the problem starts.

Re: Launch HN: Airhart Aeronautics (YC S22) – A modern personal airplane

#238

Post by blt »

BWStearns wrote: post #224
Majestic121 wrote: post #59

While I think the project is pretty cool, I can't shake the pollution side of things out of my mind. Air transport is one of the most polluting ways to travel, and I would expect a single person airplane is even worse than a full A380. Is there anything you're doing to alleviate this issue ?

Some of the LSAs I've flown are not actually that bad pollution/climate wise. Slightly less green per mile than my mini cooper, way more green than basically any common American pickup truck.

MPG-wise sure. Emissions-wise almost certainly not. Airplanes don't have catalytic converters, exhaust recirculation, etc.

Re: Launch HN: Airhart Aeronautics (YC S22) – A modern personal airplane

#239

Post by epolanski »

It's insane the length we go as humans (in the US at least) to not invest in the easiest, most cost-effective and environmentally friendly mode of transportation: trains.

Hyperloops, wider and wider highways, now personal airplanes.

Anything but goddamn trains.

It's mental to me.

Wish the best to the startup, after all they are filling a void someone else would, but still, not happy with the direction transport is going, which seems backwards sometimes.

Re: Launch HN: Airhart Aeronautics (YC S22) – A modern personal airplane

#240

Post by smackeyacky »

windexh8er wrote: post #129
sethkim wrote: post #83

Instrument-rated pilot (and engineer) here. First - congrats on the launch! I think you're working on an interesting set of components that will prove useful to GA aircraft technology. Bringing fly-by-wire, and lowering the cost of maintenance/manufacturing are both great efforts. That being said, my personal view is that stick-and-rudder control is one of the less critical components to improving GA safety. Everythi…

> It may sound snobby - but I'm not super excited about the idea of lowering the barrier to entry for GA on a foundational skill basis. Like the light-sport rating, it encourages more people to be in the (already congested) airspace system who haven't really gained all the other skills necessary or experience to be there. I'm not a pilot, but I've always wanted to go down the path. In theory - this should be rather e…

I wanted to do this too and was in a financial position to start lessons. Had raced cars in the past, rebuilt cars, mechanically savvy, fiddled around a whole heap with flight simulars, got excited about it. Paid my money for the initial 3 flights.

First time up (in a Cessna) beautiful clear day, low wind. Once we had done the safety checks I was instructed to taxi the plane. It was about as complicated as a ride-on mower and the throttle pull I swear is identical. No problem.

Instructor took over and punted the plane into the air. I was terrified. As I've written here before, a Cessna is like a Volkswagen Bug that somebody has thrown into the air. They shudder and shake and dip and every tiny pocket of turbulence throws them around. I completed the lesson without conveying my terror, did the turns, was able to identify stuff on the ground. Instructor landed the Cessna and I thanked him and told him I wouldn't be back.

I bought a motorcycle instead. They feel safer.

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