Visibility needs, wants, myths

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Vigilant1

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Technology may someday change things, but "see and avoid" is now not only a good idea, it is my responsibility and the law (in VMC, etc). So I need to be able to see the area I'll occupy soon, and a reasonable distance around that path. If my plane has a deck angle/nose geometry such that I can't see if I'm descending onto someone on my normal descent glidepath, then that needs to be adressed.
Other than that, I'm most interested in the area about +/- 15 degrees from the horizon, from wingtip to wingtip, but mostly within 45 degrees of the nose. That's where the closure rates can lead to short effective windows to see and act.
 
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AdrianS

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Would you consider a camera a viable add-on to cover a blind spot?
I've been quite impressed with the latest gen reversing cameras in cars, and they're pretty low power / light weight.

Obviously they may fail, and you'd have to allow for that.
 

TiPi

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The camera would be no problem, but where do you put that large screen needed to be able identify any objects? Unless there is a smart way of identifying and displaying an object in the camera range, it would just give you a false sense of security
 

BJC

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Would you consider a camera a viable add-on to cover a blind spot?
I've been quite impressed with the latest gen reversing cameras in cars, and they're pretty low power / light weight.

Obviously they may fail, and you'd have to allow for that.
I have experience in a couple of airplanes with lousy forward and forward-down visibility that can be concerning if proper clearing via yaw and or roll is not utilized. Taxiing those airplanes requires slow forward speed and diligent S-turns.

Try looking at something 1/4 mile away with an auto’s backup camera. I find it not acceptable for seeing other aircraft or for seeing to land. I think that it would be OK for supplementing visibility for taxiing.


BJC
 
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BJC

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The question of poor down visibility came up in the Horton 2 seat thread.
I will also note that, using an 8 year old EFIS with synthetic vision, it is possible to land an airplane that is directionally stable on the runway without any visibility outside the cockpit. But, where I fly, non-ADS-B aircraft in the area would be a great concern if flying by synthetic vision alone.


BJC
 

bmcj

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I’m Not sure if a camera would be suitable for spotting traffic in the air, but I’ve always thought that it would be good for seeing the ground for pilotage enhancement in something that lacks downward visibility (or for aerobatic box sighting). I also think that a couple of well placed cameras would be good for spotting wingtip clearance while taxiiing and also for forward taxi visibility in extreme taildraggers.
 

Dan Thomas

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So far, there is no viable substitute for the human eyeball. Resolution, night vision (non-infrared), degrees of coverage--are all better when you can actually look at something. I want to be able to see a lot more than 45°, too, since a faster airplane coming at me from 90° will be outside that 45-degree limit until it hits me.

Airplanes are all a collection of various compromises. BJC's biplane is an example of a visibility compromise necessary for short-coupled aerobatic taildraggers, but for most of us there really isn't much excuse to own an airplane that's half-blind. Isn't 90% of the fun being able to see the world from a privileged viewpoint? If I had to look at a screen I might as well stay safe at home and fool with the computer flight sim.

And paint your airplane yellow or scarlet or some firetruck green so other pilots can see it. Not some pseudo-military camoflage job; to me, that's just asking for trouble.
 

TFF

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This happened last week. On flight following at 7000. ATC tells us there is IFR traffic on the right. He pops up on our ADSB. We get a visual. Pretty sure he sees us. We descend 500 because he is aiming at up. He got as close as he could because he had magic electronic box too. We helped the controller out. He helped us out. This other guy was going to use every inch of margin. It’s good to have visibility, but I bet someone in a hard to see out plane sees more than the most in a regular plane because he is looking, hard.
 

Twodeaddogs

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it's a bit like driving different cars; yours, well, you are used to it's characteristics so you don't notice how much you move your head to see around the A-pillars or how hard it is to look out of the rear window when reversing. I'm tall so flying aircraft like the 1940s Taylorcrafts are hard work as you are constantly moving your head in the circuit, looking for aircraft, whereas flying a Zenith or a Rallye or a Jodel is so much easier.
 

Topaz

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It also depends a lot on what the airplane's role is. A high-speed cross-country cruiser can "get away" with a lot less visibility (and often does, due to pressurization) than, say, a sailplane. A sailplane has different visibility needs than a STOL bush-plane.

For high-speed cross-country, you need enough visibility for see-and-avoid in the pattern and down "low and slow" approaching an airport. Up at cruise, you're likely going to be either IFR or have flight following telling you about possible conflicting traffic. Pressurization forces smaller windows, trying to avoid a big weight penalty.

Sailplanes thermal. Meaning they tightly circle in the column or bubble of rising air, and it's a fair bet that one glider won't be alone in that thermal. I've been in single thermals with five other gliders, myself, and have seen video and still photos of big thermals with 10, 15, and even 17 gliders all circling within 200-300 yards of each other, and maybe 200 feet altitude separation from the lowest in the gaggle to the highest. Power pilots think we're crazy, but it's the way we fly. Clear and unobstructed visibility all around is critical to safety. The only thing that's allowed to compromise visibility is drag reduction.

STOL bush-plane pilots need to be able to look down. That little grass field, bit of dirt road, or sandbar doesn't have any approach aids, and if you can't see it, you can't land there. Visibility upwards is far less important, which is one of the many reasons you see so many high-wing bush planes.

There is no single solution. There's no "correct amount" that will work for all airplanes. What would be acceptable to a powered cross-country airplane or bush-plane would be tantamount to suicidal in a sailplane. A sailplane canopy strong enough to handle pressurization would be enormously heavy. A low-wing bush-plane would be virtually useless. It all depends on the use-case for the particular airplane.
 

Aesquire

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Forward and down angle needs IMHO depends on angle of descent. ( effective glide ratio )

That's based on experience in 4/1 L/D gliders. Like Bush planes, you land fairly steep and flare. By 8/1 you don't need to see as close. Etc.

OTOH you don't typically need to see straight down unless you're under a round parachute. And you won't land there, anywsy. You're going to be blown toward the power lines or barbed wire fence. Murphy's law. DAMHIK.

What's "standard" approach angle for a, say, RV-7 or a C-172? Typical airport, U. S. ?

I love the view on that Chinook. :)
 

Aerowerx

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"Everyone" talks about using a video camera mounted in the nose for downward visibility.

But there is a cheaper, lighter, more reliable method, if you don't like the view over the nose.

Just put a window on the floor! Or make the nose cone out of clear lexan!
 

Vigilant1

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But there is a cheaper, lighter, more reliable method, if you don't like the view over the nose.

Just put a window on the floor! Or make the nose cone out of clear lexan!
It might work for some niche configurations, but would be impractical for the rest. There's often an engine up there, an instrument panel, rudder pedals, and a pair of legs. In the real world, the floor takes a beating (grit, shoes). For most fixed wing acft, there's not much of interest directly below the aircraft, and looking 20 degrees below the horizon, even at an 15 degree deck angle, would be well forward on the "floor". Grazing angle through the plastic is also a factor for consideration.
 

Marc W

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My visibility requirements changed when I moved from southern California to western Colorado. I bought my CX4 in California and loved the visibility I have with the low wing and bubble canopy for flying in the congested airspace there. And there isn't much to look at on the ground of any interest to me anyway.

Here in Colorado, where the odds of encountering another airplane are very low, I would much rather be able to see down. Partly because it is new country and I am still exploring the lay of the land. The other reason is that one of my favorite pastimes is to fly around the Grand Mesa looking for elk. The low wing is really inconvenient then. If I build or buy another airplane it will be a high wing.
 

BJC

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Here in Colorado, where the odds of encountering another airplane are very low, I would much rather be able to see down. Partly because it is new country and I am still exploring the lay of the land. The other reason is that one of my favorite pastimes is to fly around the Grand Mesa looking for elk. The low wing is really inconvenient then. If I build or buy another airplane it will be a high wing.
It’s a fairly simple mod to be able to put the wing on top. See https://www.aircraftspruce.com/catalog/eppages/christen801.php


BJC
 

Hephaestus

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The camera comment comes up a lot (not just by me).

You wouldn't be using a small screen and .3mp camera to spot traffic. In my case - I used it to verify gear down while waiting a repair (johnson bar felt funny, couple worn parts and long eta's) purely peace of mind. Mounted in the tail, used a suction cup GPS mount screen to the windscreen.

For its purpose - verify gear down. Worked great. Also let me ballpark verify my height at flare. And let me see the center line flashing down beneath me. While it was installed I did reference it more than I thought I would.

So... For issues like the perceived horten viz issue - where i still don't think there will be one - I can't see it needing a high AOA approach... similar camera again near the tail - looking forward could fill in some blanks.

You'd never focus on it in the panel... I don't know why anyones thinking sitting there staring at it looking for a tiny 1px spot on the screen to find traffic...
 
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