Basic Configuration for a "Safe" airplane

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PiperCruisin

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The two single largest causes of accidents listed in the Nall report are "Loss of Control" during landing, and "Loss of Control" during takeoff.
The Nall report is always interesting, but not super clear. Sometimes I prefer to just look at the NTSB reports. Here what I get out of it, looking mainly out of fatalities for GA fixed wing:
1. For general categories, takeoff accidents lead with 23 fatalities out of 111 accidents while weather is a close second with 21 of 23. Landing is 1 out of 322. Takeoff is more dangerous than landing. A bad decision with respect to weather is a good way to die.
2. Looking at the details of the categories, Stall/spin/loss of control is about 39% of fatalities. 14% weather, 7% hitting something, 7% fuel management, and 33% miscellaneous. So, use good technique base-to-final, be careful when the weather gets iffy, don't be an idiot showing off, use good fuel practices (cause running out is embarrassing), mind the details cause one of those might get you (like high density altitude).
 

TFF

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RC airplanes no. Flight stability are for drones. For real model builders and fliers, it’s an important distinction that the AMA did not vocalize off the bat, hoping to capitalize on more memberships. We modelers have been paying for it ever since.
 

don january

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I believe that if there is some equivalent of a "longitudinal study" showing the causes of accidents over time, we would see that lower levels of pilot skill are going to be associated with accident rates. Perhaps our aircraft accident data aggregator par excellence Mr. Wanttaja has this data available, or can number-crunch whatever data is available, to see if I'm anywhere near on the right track here or not.

Like many others here (many of whom have far more flight experience and formal education than me), I believe pilot training will make the biggest dent in crash/injury incidents. All the other innovations absolutely have their place - the parachutes, Roncz's ICON wing, the electronic gadgets, ADS-B, FLARM, technical improvements in fuel/ignition, etc.

But stupidity or ineptness or judgment or skill or critical thinking (the human parts of the pie chart) is still the biggest problem IMHO.
"Bravo" Victor Bravo. Pilot training is the key and reparation of flying such as an Ag pilot helps. It doesn't help any by changing crafts frequently and conditions.🕵️‍♂️
 

rotax618

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I saw a good demonstration of the ability of a model flight controller to fly a model away from a crash, recently a guy at the model field was doing some pretty radical aerobatics, a violent pullup caused the engine to depart the airframe, he pushed the safety on the transmitter, the airplane straightened out of the spin and he was able to “land” it with very little extra damage. It was amazing that the control surfaces were able to overcome the change in CG.
 

don january

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RC airplanes no. Flight stability are for drones. For real model builders and fliers, it’s an important distinction that the AMA did not vocalize off the bat, hoping to capitalize on more memberships. We modelers have been paying for it ever since.
Yep. what are the dues these days for RC AMA ? Great thing to have if flying in a populated area. I would think that is another thing to protect your craft for flight
 
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blane.c

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There are many configurations that are safe, it is not realistic to pick one without a mission implied. Mostly I figure you can teach a monkey to fly, unfortunately you cannot teach a monkey good judgement. It is imperative for a pilot to know the limitations of the aircraft they are flying and exercise good judgement. Stay within the flight envelope of the craft in question.
 

Bigshu

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Thread drift can be fun, and training is always good, but not the topic of this discussion, nor is auto land or any other complex auto software. Just design elements, and small things that can add up to a package that helps to stack the deck in favor of the pilot.
Try coupling the rudder and ailerons, and limit elevator travel, a'la Ercoupe. Still, stall proof doesn't fix CFIT or running out of gas!
 
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Bigshu

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5) And for the electronic gadgeteers, a master caution light system (idiot light) where a low fuel condition (15% remaining or less), oil temperature, oil pressure, CHT, etc. puts a red light in the pilot's field of view.
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.
 

Bigshu

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The two single largest causes of accidents listed in the Nall report are "Loss of Control" during landing, and "Loss of Control" during takeoff.
There's lots of published info on how a lot of LOC on landing accidents could be fixed by using stabilized, straight in approaches. Like the airlines. I read an article a few years ago that talked about circular approaches being a good compromise, getting away from the squarish cornered oval approaches that cause a lot of the base to final turn accidents. Just teaching pilots to go around when the approach is botched could help a lot. Too many try to salvage a bad situation, and often get away with it. A go around would often be much more prudent.
 

Bigshu

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Eventually you will lose the legal right to human operate a vehicle where it is useful AND even in the un-useful places you won't be able to get insurance.
Well, technically, driving isn't a right. It's a privilege granted by local authorities, based upon written, practical, and vision exams.
 

Bigshu

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1) Sufficient vertical "side area" underneath or clear of the horizontal stabilizer, so that the vertical stabilizer (fin) doesn't get "blanked out" at high AoA and cause spin recovery issues.
I see these a lot more on new designs, particularly European designed LSAs. A good idea, and easy to incorporate, even in a taildragger.
 

Marc Zeitlin

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I don't think we have to worry about that in our lifetime for either cars or aircraft - though I'm not to sure about aircraft since they are are orders of magnitude easier to automate...
That's what I thought too, until I spent the last 3 years or so working with/for a company that's been developing Autonomous aircraft. Since they've come out of stealth mode, I can mention that it was:


While I do believe that aircraft may be slightly easier to automate than cars, I think the # of orders of magnitude easier is somewhere in the neighborhood of 0.2.
 

Marc Zeitlin

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1) Sufficient vertical "side area" underneath or clear of the horizontal stabilizer, so that the vertical stabilizer (fin) doesn't get "blanked out" at high AoA and cause spin recovery issues.

2) Proper twist or other airfoil components that result in strong inboard-first stall progression and give the pilot roll control at and past the stall.

3) Pronounced wing root and/or tail buffet to deliver a clear non-electrical seat of the pants warning to the pilot, regardless of (or in place of) any and all electronic gadgetry, lights, sounds, stick-shakers, or pilot shock collars.
All three implemented in the ICON A5.

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.

My Skyview A/P has a "Level" button - if I get disoriented, I can punch that and it'll hold heading and altitude.

So I think that the combination of innate design features and "automation" are useful and necessary to increase safety levels with the levels of training that we're likely to see in GA.
 

Bigshu

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So I think that the combination of innate design features and "automation" are useful and necessary to increase safety levels with the levels of training that we're likely to see in GA.
At the pipeline, we used a combination of engineering controls and frequent review/revision of policy and procedure to reduce problematic operations. Sometimes it's easier to engineer the fix (automation to grab the pilot's attention, or reduce task saturation) than it is to train to a level of proficiency on new procedures. When push comes to shove, and alarms are going off, it's very easy to go with the procedure you've done a million times as opposed to the improved procedure you've only done a handful of times.
 

Dan Thomas

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In the flight school were were taking ab inition students all the way to CPL/IFR. We would not train to the PPL minimum like most schools do. Most are just trying to get them past a checkride, and so we see LOC accidents because they just have not achieved much proficiency. You'll see them approaching on short final, way too fast and diving at the runway, and touching down fast and flat and far down the runway. What can you expect except eventually an accident?

Everyone forgets much of their schooling, and pilots are no exception. But those that have had too little training have less schooling they can afford to forget. Most PPLs seem to stop actively learning once they're licensed. They think they have "arrived." The stuff they don't know sometimes kills them.

Wire cutters on GA airplanes? Why? What are they doing buzzing around at that altitude? Or scud-running? They keep doing that and it will be a birdstrike or an engine failure in a bad spot or an accelerated stall/spin when they suddenly pull up to avoid something. Or cellphone tower guy wires catch the wing. Cropsprayers and low-operation helicopters use wirecutters, but for the rest of us it's just more weight and drag and false security. We could add all that fancy stuff like 'chutes and five-point harnesses and helmets and AoA indicators and ADS-B and so on, and still stall on takeoff trying to clear the trees, and crash and burn along with all the fancy stuff because we couldn't be bothered to do some takeoff calculations for takeoff roll and obstacle clearance for that runway on that day. Or bang into the granite because we wanted to get home so bad in that awful weather.
 

BBerson

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The ag-planes are an engineered configuration for crash safety with the pilot in a cage behind the load.
Any sort of crash structure is useful.
 

BJC

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Wrt pilot training:

HPI, Human Performance Improvement, is a program that teaches people how to learn from others’ mistakes, to recognize error-likely situations, and to actively avoid mistakes. Lots of www info available these days to satisfy your curiosity. It sounds simple, but is difficult to incorporate into large organizations, primarily because of individual resistance to changing one’s long-established work habits.

Twenty years ago, such concepts were new to the electric power generation industry. An early implementation: After two years of training employees and collecting base line data at electric power generation plants of two utility companies, we realized an audited 60% reduction in significant events the third year, and another 50% audited reduction the fourth year. The economic benefits were outstanding.

Such a program could, assuming widespread acceptance by pilots, make a major reduction in GA aircraft accidents and fatalities. Unfortunately, I do not see a path to widespread implementation. 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, so why fly the reverse? It is an error prone situation, with lots of variables, including density altitude, speed at pitch-up, peak altitude, airspeed at altitude, g loading on the pull-through, etc. Even the “best” have wasted a perfectly good airplane when making an error in calculating the key references. See
There have been 5 or 6 fatals in GA airshow routines from the same errors.

Wrt to aircraft design:

I had a brief flight in an imported aerobatic airplane that a friend owns. It is unique in my experience in that I could not sense a change in airspeed by a change in the stick force. For me, that dictated that I made frequent references to the ASI. That created what, in HPI, we called an error-prone situation.

A design safety feature, for me, would be flight controls that have self-centering and provide feedback to the pilot. Example: a Pitts can be flown right at the edge of a stall, because the controls provide feedback that the airplane is within a fraction of a degree of AoA of a stall, regardless of speed.

I this interests you, don’t fly around waiting for the FAA or your CFI to do something, research it yourself.


BJC
 
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