Basic Configuration for a "Safe" airplane

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Dan Thomas

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Now, as a bike and kart racer, that never mattered to me but in an ice race car you can bet it did (does if our club ever gets off their aging butts and organizes a series again).
Ah. Winter sports in Saskatchewan. Except in August when the ice is too thin....😁

I live in SK, too, much further south, about an hour south of Swift. Gets hot here in the summertime. We've seen 42°C at times. And, of course, -40°C in the winter once in a while.
 

Dan Thomas

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Because that's actually pretty darn reasonable; assuming there's no insane $ associated with annuals...
There are costs if you're going to stay legal in a TC'd airplane. The ICA: https://www.amsafe.com/wp-content/uploads/2018/07/ICA-Instuructions-for-Continued-Airworthiness.pdf

We looked after several airplanes that had it. And we had the test box that we used annually, and that test box had to be calibrated every couple of years, too, at the factory. Not many shops will have that thing.
 

Hephaestus

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There are costs if you're going to stay legal in a TC'd airplane. The ICA: https://www.amsafe.com/wp-content/uploads/2018/07/ICA-Instuructions-for-Continued-Airworthiness.pdf

We looked after several airplanes that had it. And we had the test box that we used annually, and that test box had to be calibrated every couple of years, too, at the factory. Not many shops will have that thing.
Well we're in the homebuilt world here :) I mean the gas cylinder can't be that crazy expensive every 10 years. So assuming <300$ costs every year - that'd leave it as a ROI if there's a reasonable insurance discount for having it.
 

Sunbird

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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
Helicopters have a long track record as VTOL aircraft... Ever tried to insure one?
The Auto Gyro in the 1920-30's was thought to be the solution to overcome the dreaded stall-spin accidents that plague fixed wing aircraft. It certainly has the second worst efficiency of all flying machines (pure wingless rockets/jets as flying machines are worst). If one add wings (Gyrodyne), I suspect it's potential efficiency may be better than that of a helicopter, but of cause never as good as that of a fixed wing aircraft - because of the weight and drag penalty of the rotor(s) in forward flight.

The bad track record of the helicopter is mostly due to its mission, it nearly always operates in an environment of obstacles and snares, accentuating it's Achilles heel, the tail rotor. Normal aircraft supposedly only operate in this hazardous environment during the take-off and landing phase, but there stall/spin induced loss of control aggravate the outcome as impact angle is less than desirable.

With the continued loss of airfields worldwide, VTOL might become less of a nice-to-have to more of a necessity in order to keep our dreams flying. With modern technology (such as short burst of electrical power for take-off to assist the IC engine, cruise in IC only) one may need to revisit the Gyrodyne in its various forms (my dream is twin rotors) as a possible safer aircraft (=mission).

Heavenly and Devine, what could be better.
 

drive330

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The basic configuration for an aircraft that is a “Safe” configuration is one not capable of flight.
Anything capable of leaving the ground can kill you.
For example a park near where I grew up had a Grumman Panther that the village elders had acquired from the Navy back in the day.
As a side note the kids were all over the Panther, the only item removed by the Navy was it’s engine.
Turns out they missed the “ejection seat” item on the de-commission check list….
True story.
Quietly they removed the mortar shell
that powered the ejection seat, no hoopla back then.
With an engine that Panther would fly, making it dangerous.
Eventually the village elders elected to encase the Panther in chicken wire and concrete, rendering the Panther incapable of flight, and thus perfectly safe.
I offer that chicken wire and concrete combined to be the perfect safety solution.
 

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Bigshu

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With the continued loss of airfields worldwide, VTOL might become less of a nice-to-have to more of a necessity in order to keep our dreams flying. With modern technology (such as short burst of electrical power for take-off to assist the IC engine, cruise in IC only) one may need to revisit the Gyrodyne in its various forms (my dream is twin rotors) as a possible safer aircraft (=mission).
That's the future problem at the back of my mind. Maybe we need to teach AOA management along with learning the V speeds of the aircraft we're flying. I don't remember much mention of AOA during training, but hitting the speeds was drummed in. I guess it's impossible to hit the speeds right and not have a safe AOA? That doesn't sound right...
 

Pops

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Because idiots are allowed to vote?
And the idiots think they are so smart that they need to tell the little people how to live.
The height of ignorance is when you don't know and don't know that you don't know. So you think you know everything. That makes you a politician.
 

Bigshu

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I wonder what insurance discount would be involved...

Because that's actually pretty darn reasonable; assuming there's no insane $ associated with annuals...
It'd be interesting to see the checklist for annual inspection the manufacturer supplies. If it's just a visual and use the device self test module, that doesn't sound bad. Even if it's periodic repack with replacement of the inflation device, that's pretty cheap if you go by marine flotation devices (yes, it's apples and oranges, but the bladders and inflation devices are roughly similar).
 

Bigshu

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And the idiots think they are so smart that they need to tell the little people how to live.
The height of ignorance is when you don't know and don't know that you don't know. So you think you know everything. That makes you a politician.
Everyone operates with imperfect knowledge. Both known unknowns and unknown unknowns can trip up anyone. It's not a unique problem to politicians. It is arrogant to believe you know all.
 

Pops

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Everyone operates with imperfect knowledge. Both known unknowns and unknown unknowns can trip up anyone. It's not a unique problem to politicians. It is arrogant to believe you know all.
Yes, that is the result.
 

Dana

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Watch the politics. Sure, lots of politicians are idiots, but naming them (one post deleted) makes things get ugly. Stick to airplanes, please.
 

Dan Thomas

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That's the future problem at the back of my mind. Maybe we need to teach AOA management along with learning the V speeds of the aircraft we're flying. I don't remember much mention of AOA during training, but hitting the speeds was drummed in. I guess it's impossible to hit the speeds right and not have a safe AOA? That doesn't sound right...
I taught a couple of classes in the local ground school, by invitation, and dealt with AoA in one of them. Even their instructors were looking a little surprised at what they hadn't understood. It's one of those subjects that get too little coverage because the instructors aren't clear on it. Carb ice is another.
 

PMD

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I never gave it much thought, as during my ab initio training I simply tried to think like an air molecutle and tried to learn how a wing flies. Even so, all of this attention to numbers and theories just doesn't compare with being able to learn to actually fly the wing. Early in my licensed times, I started flying with a bunch of people who taught us to live at the very limits of control - all heads up. Once one gets to that stage, THEN all of the numbers take on a much better meaning and understanding. I think we get so bogged down in the business of getting people licensed that we tend to forget to teach them to fly (and set the stage to keep learning). Those first 40 hours are not just the passport to start the learning process that never ends. We instead tend to often regard licensure as THE end of the process.
 

PMD

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Ah. Winter sports in Saskatchewan. Except in August when the ice is too thin....😁

I live in SK, too, much further south, about an hour south of Swift. Gets hot here in the summertime. We've seen 42°C at times. And, of course, -40°C in the winter once in a while.
If our US company survives COVID, and when the land borders are open again - I go through Val Marie on the way to Monchy/Morgan to get to my office. Will have to stop for a visit then.
 

PMD

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And the idiots think they are so smart that they need to tell the little people how to live.
The height of ignorance is when you don't know and don't know that you don't know. So you think you know everything. That makes you a politician.
Interesting choice of words. I always told our kids that if they ever expected to be a good scientist they would have to know absolutely for sure what it is they don't know absolutely for sure.
 

rotax618

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If we are discussing light Sports Planes (one and 2 seaters < 1/2 ton TOW), it may be beneficial to forego some efficiency in the name of safety. Very low aspect planforms have been shown to be both stall and spin resistant, the shape of the wing planform could provide other safety benefits including a larger internal volume, greater structural strength/weight and more crashworthiness. I know the higher/faster/further pundits insist on high aspect thin slender wings, but they “generally” have a more sudden stall/spin transition.
I am aware there are devices that can be included in the design that can alleviate these problems but they add complexity and weight to the very light homebuilt class, and are not entirely foolproof.
As they said about the Cub “it flies so slow it can barely kill you”.
 
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