Basic Configuration for a "Safe" airplane

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Voidhawk9

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John Denver did not stall or spin.
Not all canards have 'high' stall speeds, though the most well known and common Ez types have higher stall speeds than a 'similar' RV, it is true.
 

Jimstix

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Maybe we could improve the odds of survival post-impact with terra firma since we cannot improve the humans very much.

The two main killers in plane crashes are blunt trauma from the structure collapsing while not providing sufficient energy absorption and the post-crash fire.
Improve the energy absorption by design/build/test/repeat. A sizable human factors database is available from the auto industry and from the aircraft safety literature. Several sort-of successful fuel tank fire reduction techniques have been dreamed up. The question here is how much extra mass are you willing to carry around prior to the crash?

Airplanes, like hamburger, are sold by the pound (or kilo). More mass, more dollars, whether it is for safer cockpits or safer fuel tanks

Suppose that adding 23 lbs. (10 kg) to the average airframe reduced the number of deaths by 1%. Great, but that might not be enough to make it worthwhile.

How about a 10% reduction in general aviation deaths by adding 230 lbs. (100 kg)? Maybe, AVEMCO would say "Okay, you have the enhanced structural and fuel tank upgrade, so you get 10% off your yearly insurance bill." This may save you money but your LSA (+100 kg) flies badly, if it flies at all.

These are not easy trades. I'd like to hear some discussion on this.
Jim
 

Marc Zeitlin

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The safest aero wise is a canard/tandem wing style that refuses to departure stall, or spin in on approach.
As much as I love canards, and I do, the statistics do not bear out your claim. VE's, LE's, Velocitys, COZYs, etc. do not have substantially different crash/fatal crash statistics than other homebuilt aircraft. While my aircraft has saved my ass a couple of times by not stalling on a base to final turn when I had a bit of ice on the canard/wings, the overall statistics don't show rates different enough, either higher or lower, to make statements about the overall safety record being better than other types of aircraft.

Wish it were otherwise, but if wishes were horses...
 

PiperCruisin

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They typically have higher stall speeds than lower performance aircraft, but for equivalent performance (Glasairs, Lancairs, etc.) the stall speeds are fairly similar - within a few kts.
Agreed. Higher performance, higher wing loading means everyone needs to be on their game. Speed is fun, but there is no free lunch.
On the opposite side of the spectrum I also flew paragliders. I found them to have a non negligible danger risk.
1. Your legs are the landing gear.
2. The amount of up lift required to keep you in the air versus the amount that could kill you seemed like too narrow a band for my liking. Beginners did ok and so do experts. Its the intermediates/novices that are expanding there envelope and get experience that end up in trouble.
 

Victor Bravo

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2. The amount of up lift required to keep you in the air versus the amount that could kill you seemed like too narrow a band for my liking.
Precisely why there will be only rigid, aero controlled wings mounted on any flying machine this author's arse will be sitting in.
 

speedracer

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On my first flying job, my boss told me to fly on one fuel tank and check the time it took for the engine to quit. Then you know how long you can fly on the other tank before the engine quits for good. I told him, no thanks.
I used to ride with my brother in law in his Apache. He would routinely run one tank dry before switching tanks, I guess, to have a known amount of fuel left. Of course, he never told his passengers that he was going to do this. Talk about making the hair on the back of your neck stand up when the engines quit! LOL.
 

Pops

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John worked full time hauling skydivers in his Beech-18. ( my hanger neighbor). I was in the right seat when we went to a local larger airport to get the oxygen tank refulled. Just turned base from downwind he switched to the, he thought, fuel tanks that had more fuel. He really switched to two empty fuel tanks. When he switched the fuel valves I glanced down as the fuel pressure gauges hit zero and both engines started to wind down. Never seen John move so fast as he was turning the fuel valves back to the other fuel tanks with both hands at the same time.

Never forget that day because as we taxied out to the runway there was a DC-3 taxiing out behind us. Told John if I had a camera, I would jump out and take a picture. Not often you see this anymore. (Hogan Air's DC-3).
 
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Dennis DeFrange

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Settin in the back seat of a twin Apache . Pilot was going to do a touch and go . Firewalled it and I asked if the plane would take off full flaps . There was an abrupt (OS) up front and then a few moments of chaos . I'm guessin , we were about to bite the wennie .
 

cluttonfred

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It's not a popular point of view, but I do believe that the aircraft with the least amount of demands on the pilot is, in fact, the safest. A plane with only two controls (up/down and left/right) could, in fact, be very safe if set up correctly:
  1. A single throttle lever which, when pulled back below the idle setting deploys spoilers/air brakes/landing flaps for adjusting glide path even with the engine off.
  2. A wheel/yoke/stick for turning left and right using rudder only, ailerons only, or interconnected rudder ailerons, no pitch control.
  3. Rugged tricycle gear steerable from the same wheel or yoke, or differential hand or foot brakes.
It wouldn't be very maneuverable or terribly exciting but it would also not be subject to pilot error causing a loss of control in the usual stall/spin scenario. You'd need to test passive stall/spin recovery in the case of violent turbulence. I imagine a nice modern cockpit like a Tesla with dual yokes and a large central lever like an inverted U for throttle/air brakes.

OK, I've got my fireproof Underoos on, flame away!
 
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Voidhawk9

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Well, modern airliners are a bit like that. And it does indeed work well when used as intended and when things are working like they are supposed to.
But... then you get 'lazy' pilots who fail to handle the unexpected very well.

Flame off. 😁
 

Bigshu

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It's not a popular point of view, but I do believe that the aircraft with the least amount of demands on the pilot is, in fact, the safest. A plane with only two controls (up/down and left/right) could, in fact, be very safe if set up correctly:
  1. A single throttle lever which, when pulled back below the idle setting deploys spoilers/brakes/landing flaps for adjusting glide path even with the engine off.
  2. A wheel/yoke/stick for turning left and right using rudder only, ailerons only, or interconnected rudder ailerons, no pitch control.
  3. Rugged tricycle gear steerable from the same wheel or yoke, or differential hand or foot brakes.
It wouldn't be very maneuverable or terribly exciting but it would also not be subject to pilot error causing a loss of control in the usual stall/spin scenario. You'd need to test passive stall/spin recovery in the case of violent turbulence. I imagine a nice modern cockpit like a Tesla with dual yokes and a large central lever like an inverted U for throttle/air brakes.

OK, I've got my fireproof Underoos on, flame away!
I'm exactly with you on these opinions. I agree that keeping the pilot task saturation low can lead to better situational awareness/pilot control. I think a little more coordination of controls in the design phase makes for a popular aircraft (thinking of the Ercoupe here). I'd be very interested in a modernized Ercoupe, with or without rudder pedals, designed for modern size occupants, with a single throttle control set up as you describe, with a flap/spoiler/ speedbreak interconnect. I think that would be a pretty safe, not neccessarily "sporty" airplane. If you didn't have rudder pedals, you could make the throttle a foot pedal on the right, and the spoiler/speedbrake a pedal on the left. How much easier to train a car driver with a system like that? NOW we'll see the flames!
 

Bigshu

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Suppose that adding 23 lbs. (10 kg) to the average airframe reduced the number of deaths by 1%. Great, but that might not be enough to make it worthwhile.
Well, how much do airbags weigh? Seems like the shoulder harness airbag solution in cars really cut down on serious injury/fatalities in cars. What's wrong with wider adoption of chutes for planes? What's the fatality rate for planes with chutes? If a crumple zone up front would help, how much would some extra sheet aluminum and longer longerons weigh? Seems like this is a solvable problem that is being held up by the regs on how you certify aircraft.
It reminds me of sailboat designs from the 80's, versus the way they became shaped in the 90's. Big change from narrow sterns and longish overhangs, to wider sterns with chines and plumb bows. The wider sterns and plumb bows added interior volume and initial stability, but had an impact on handling in following seas and other metrics. The buyers liked the new changes, but the old boy network hated the change from "traditional, time tested design". Sometimes we're our own worst enemies.
 
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