Basic Configuration for a "Safe" airplane

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Pilot-34

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Yeah. Why? Span loading, blown lift, clear forward viz, near cg.
Engines in the wings disturb the airflow were the wings if they throw a propeller it’s likely to go someplace where it will hurt passengers and crew and of course by having them oh near the center of gravity they don’t counterbalance pilot and help get him out from under the wings
 

Victor Bravo

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I do so hate to push this delightful discussion back from the "theoretical" to the "applied", but.... Dearest Mr. Wanttaja, o keeper of ye olde mystic numerology, do you have any data on what are the differences in accident rates between the 2-control Ercoupe and the 3-control Ercoupe, or the (control interconnected) Tri-Pacer and the (interconnect disabled) Tri-Pacer?
 

Pops

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I do so hate to push this delightful discussion back from the "theoretical" to the "applied", but.... Dearest Mr. Wanttaja, o keeper of ye olde mystic numerology, do you have any data on what are the differences in accident rates between the 2-control Ercoupe and the 3-control Ercoupe, or the (control interconnected) Tri-Pacer and the (interconnect disabled) Tri-Pacer?
For the Ercoupes, it flight, not running off the end of the runway.
 

TFF

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Flying is easier than driving. The consequences are different for mistakes though. That can be a big hold up if you have a good imagination. I know I learn to the lowest common denominator. Bar high or bar low, I’m going for the bar. I find it’s better to be pushed up than settle down. It can be a challenge when you know you can sluff off but ask for someone to push you. Your average will be somewhere in the middle, so low bar minimum just means you have nothing extra to give.

Someone might struggle wanting to do stalls, that’s when they need to do a thousand with an instructor. You may never do one on your own, but you know how to ride through it. Exposure. Flying is built on exposure. You do it and do it until it doesn’t bother you. Some pick it up fast, lucky them. Most have some form of grind.

I got a friend who was a Guard F16 pilot. Some stars aligned for sure, but the pure and simple way he got it was he asked. He had worked his way into feeder airlines, so he knew how to fly, but was still green in a lot of ways. Still a kid. Put up with the interview hazing which would have been a gag on SNL. The only thing they told him was he had the worst grades of anyone they had ever accepted and he should go to night school and fix some. I saw him add a helicopter rating or three. He had to work at it. Talented pilot for sure, but new wheel house. He was humble learning and he knew he needed to be. He is still learning with it all but open. In certain areas the 30,000 hours transfer. Some of the most important stuff, he is at 200 hours of skill and he is smart enough to know it.
 

Bigshu

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Most of the GA fleet is 30 odd years old and many homebuilts are just homemade copies of them. If you compare the strides made in the automotive field during this time (ABS, Stability, Traction, airbags, crumple zones etc.) it is time to re-assess the design of the lightplane.
Or older! I think airbags and crumple zones are easily accomplished these days, if you don't mind the performance penalty ( what's safety worth? A few knots off the cruise speed, a few FPM off the climb performance?). If we weren't avoiding "gizmos" in this discussion, I think APs with "one button" recovery to level flight features would be a game changer in situations where a pilot is disoriented. Training is great, but situations exist where pilot skill isn't the issue.
 

PMD

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The more I think of it, the more I think my personal pick of best layout for safety and aero would look very much like a Piaggio Avati with a "safety cell" cabin and a pair of vertically mounted pusher diesels (norrow cowling). Not so sure about the Canard part, but the three surface layout of the Avanti I think deserves some discussion.
 

PiperCruisin

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The more I think of it, the more I think my personal pick of best layout for safety and aero would look very much like a Piaggio Avati with a "safety cell" cabin and a pair of vertically mounted pusher diesels (norrow cowling). Not so sure about the Canard part, but the three surface layout of the Avanti I think deserves some discussion.
Personally, I prefer the conventional config (for singles anyways) because I like the heavy stuff in front of me in a crash. I do like the three surface config.
 

Dana

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If that was the reason, the problem likely was with the training / knowledge / skills of the CFI’s. I talked to an FAA man at Oshkosh several years ago about the recent change in stall training and also about spin training. His response was something to the effect of “There is no chance that the FAA will require spin training.” The FAA is afraid of actual stalls. {Sigh.}
Absolutely, a lot of CFIs are terrified of spins.

Another problem is that a lot of today's training aircraft are not certified for spins.
 

rotax618

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I don’t advocate including auto safety devices such as airbags and crumple zones in lightplanes, if you need these devices to survive it is usually too late.
Many safety “improvements” to some GA aircraft consist of a stall strips to tell you that you are about to spin in and a couple of extra paragraphs added to the flight manual warning you of the possibility.
A stall should be a gentle loss of a small amount of height and never result in a spin, stall/spin is WW1 aerodynamics.
Most GPSs can provide terrain warnings, many aircraft are not fitted with one.
A simple device to maintain attitude in cloud or severe turbulence would not be too heavy or complex given todays electronics.
BRS chutes have save a lot of Cirrus pilots.
There are many other design improvements that could be implemented, but it’s always best to start with a clean sheet and design with safety in mind.
 

PiperCruisin

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Absolutely, a lot of CFIs are terrified of spins.

Another problem is that a lot of today's training aircraft are not certified for spins.
At the end of my PPL checkride, many moons ago, the DPE asked if I wanted to see my plane do a spin (PA28-140). I said sure. He tried twice before giving up. Everytime, it rolled over a bit and headed straight for dirt. I learned how to do it since then, it wraps up fast and not great for the gyros.
It can do them, at least my model ('73 in Utility Cat), but the Cherokee is not a good plane for spin training. Cessna Aerobat was a lot of fun for spins.
 

Daleandee

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Flying is so expensive now that it soon will only be a sport for the wealthy.
"Soon will only be" ... I thought it was a sport for those that are wealthy now. At least that's what many of my friends believe. Should I confess to not being wealthy? I find that when I tell them I built it they realize that I might not be wealthy but I am nuts to fly my own creation! 😁
 

Daleandee

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To answer the basic question for me was to find the strongest airframe design that fit my certificate, flying style, mission, and budget and couple that with the most reliable engine that I could wrench on that my wallet could stand. I ended up with a Corvair powered Sonex. So far it has proved to be exactly what I was after.

Would it be safer with a chute? More wingspan for better climb, slower cruise, and better glide? Should it have a steel cage fuse? How about five way seat belts (as opposed to the four way installed now)? Decisions, decisions ...
 

rotax618

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Current designs are what they are, you could add terrain warning and perhaps a BRS but to exploit all possible safety, within current technology, requires a clean slate and new ideas.
 

BJC

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Another problem is that a lot of today's training aircraft are not certified for spins.
Yup. But as they say, “A pilot certificate is a license to learn.” No reason to stay ignorant just because of the FAA. Many E-AB can be spun. Pilots can get that LODA tomorrow, and start spin training this Saturday.
Many safety “improvements” to some GA aircraft consist of a stall strips to tell you that you are about to spin in
The stall strips that I have flown are there to generate turbulence over the horizontal stabilizer that the pilot can feel in the control stick to warn of an impending stall. They are not “about to spin” indicators.
Most GPSs can provide terrain warnings, many aircraft are not fitted with one.
Walk through the E-AB parking area at Oshkosh. Many have EFIS’s installed that have terrain warning. Legacy TC GA aircraft typically do not.
A simple device to maintain attitude in cloud or severe turbulence would not be too heavy or complex given todays electronics.
Ditto comments above.
At the end of my PPL checkride, many moons ago, the DPE asked if I wanted to see my plane do a spin (PA28-140).
In my PP check ride, I had to recognize, and recover from, a spin under the hood, so I didn’t actually see the spin, but it was there, and easily recognizable with a T and B. Slightly more complicated for me to recognize with the “more modern” TC that replaced the T and B.

It takes a conscious effort (i.e., holding pro-spin controls well into the post-stall) to spin a C150 or an A152, regardless of entry. Simply relaxing the forces on the controls and allowing aero forces to position the controls will prevent a spin. Simple to train, practice and master, if one wants to.


BJC
 
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rotax618

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BJC I’m sure you have the skills, my comments were in recognition of the many now deceased pilots that either didn’t have your skill or the platform and circumstances gave them no hope of ”textbook” recovery. Airplanes can be made safer !
 

BJC

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I don’t have any special skills, but I have had the interest and good fortune to have flown several aerobatic (and non-aerobatic) aircraft in all areas of the flight envelope. I fly for fun, and enjoy maneuvering to my limits and or the aircraft’s limits. I, too, can provide a too-long list of friends who have died in crashes.

I understand that this thread is about making the aircraft “safer”, but my experience is that pilot training can significantly reduce fatalities in a relatively short time (less than a decade) while modifying existing or new designs will take decades, increase cost, reduce the performance and capability of sport aircraft.


BJC
 

PiperCruisin

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Maybe the point I was making was that for the Piper Cherokee, you have to really work at it to spin it. Probably makes more sense to work on avoidance like the airlines. The typical spin entry would be base to final where you won't have time. Better to encourage a little top rudder and proper airspeed to avoid the skid.

Most accidents I read about are fuel management, CFIT/LOC from VFR into IMC or night/mountains, high density altitude, or just plain screwing around. There might be a few accelerated stall base to final, but that is probably more prevalent in higher performance aircraft. So training will always have an element of model specific training.

Maybe planes need a CFI help line, like Onstar, where the CFI can say, "Did you not look at the weather ahead? SIGMETS... hear of those? Maybe you should do a 180 and land at K--- till it blows over. Oh, and there is a TFR to your 10 o'clock you failed to check."
 
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