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pictsidhe

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A camera is best suited for close objects. Seeing an aircraft you are descending onto even 50yds away could allow evasive action ans expletives instead of pieces.
 

bmcj

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A camera is best suited for close objects. Seeing an aircraft you are descending onto even 50yds away could allow evasive action ans expletives instead of pieces.
Or even a rear view camera pointed back and skyward to see someone overtaking and descending on you in your blind spot while on final.
 
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Vigilant1

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In a few years, I'd expect the lidar units used by autonomous cars to be in mass production and relatively cheap. It would detect other aircraft, effectively filter these targets from terrain in "look down" mode, provide azimuth, elevation, and range info, provide rate of closure, and even sound the klaxon if the other aircraft will eventually be a conflict. So, you'd get everything needed to cue you to look in the right spot. Given sufficient reliability, it is even enough info to allow evasive action without a direct visual confirmation.
This all assumes clear LOS-- all bets are off in the clouds. Hey, you should be under IFR and positive control at that point.
 

Hephaestus

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In a few years, I'd expect the lidar units used by autonomous cars to be in mass production and relatively cheap. It would detect other aircraft, effectively filter these targets from terrain in "look down" mode, provide azimuth, elevation, and range info, provide rate of closure, and even sound the klaxon if the other aircraft will eventually be a conflict. So, you'd get everything needed to cue you to look in the right spot. Given sufficient reliability, it is even enough info to allow evasive action without a direct visual confirmation.
This all assumes clear LOS-- all bets are off in the clouds. Hey, you should be under IFR and positive control at that point.
Start thinking in dimensions and degrees - then having to sweep that space constantly - lidar doesn't make a lot of sense. Most units have a range much below typical separation minimums.

That said - I do remember reading something about using fisheye/spherical lenses, DSLR cameras and some serious computing horsepower to scan the sky for conflicts. But at this point you're talking a big xenon processors, multiple GPUs tb+ of ram and serious SSD hard drive space to do it... (Think fully optioned out 60k+ mac pro)
 

cluttonfred

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But at this point you're talking a big xenon processors, multiple GPUs tb+ of ram and serious SSD hard drive space to do it... (Think fully optioned out 60k+ mac pro)
Lol, but in 10 years that will be the computing power of your personal communication device (don't say phone). ;-)
 

Vigilant1

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Start thinking in dimensions and degrees - then having to sweep that space constantly - lidar doesn't make a lot of sense. Most units have a range much below typical separation minimums.
But, compared to an autonomous vehicle, our resolution requirements (angular and range) are very low and our minimum target size is very big. Also, I'd think even limited range detection and cueing would be darn useful in typical VFR scenarios. Where the problem is most acute, aircraft are limited to 250 KIAS. Even 1 mile of lidar range provides about 7 seconds of warning with 500 knots of closure. Is that enough time when you know exactly where the bogie is and where he's going? Heck, it might be the rest of your life!
 
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Aerowerx

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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.
My comment was aimed towards the delta wing/Horten pusher aircraft.

And with a clear floor ahead of the rudder petals, you would probably get just as good a view as having a camera.

And it would be more intuitive. Where would you mount the screen? How would you translate the picture on the screen to what is happening beneath your feet, unless you have the screen between your feet where the window would be anyway??
 

Aerowerx

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A camera is best suited for close objects. Seeing an aircraft you are descending onto even 50yds away could allow evasive action ans expletives instead of pieces.
Wait a minute!

What is the purpose of this camera?

Is it to see other aircraft under you, or to see the ground when about to touch down?
 

Dana

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...Even 1 mile of lidar range provides about 7 seconds of warning with 500 knots of closure. Is that enough time when you know exactly where the bogie is and where he's going? Heck, it might be the rest of your life!
Isn't that what ADS-B is supposed to be for? Though of course it only works if you and the other guy both have it...

Back to the cameras, I think a forward looking taxi camera is an option on the new WACO biplanes, no need to S-turn on the taxiway like the peasants...
 

Jerry Lytle

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A rear view mirror worked in WW2. Try an external panoramic mirror mounted at near the top of windscreen. Adds a little drag but didn't slow the Spitfire a whole lot.
 

Hephaestus

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But, compared to an autonomous vehicle, our resolution requirements (angular and range) are very low and our minimum target size is very big. Also, I'd think even limited range detection and cueing would be darn useful in typical VFR scenarios. Where the problem is most acute, aircraft are limited to 250 KIAS. Even 1 mile of lidar range provides about 7 seconds of warning with 500 knots of closure. Is that enough time when you know exactly where the bogie is and where he's going? Heck, it might be the rest of your life!
No compared to an autonomous cars ours are insanely hard... Lidar is great in that 100' ballpark with a forward (so 135ish deg?) scan that's only needing a range of 12" aff - 72". That's all they care about... Whereas aviation we need 360x360deg and a much finer resolution - half a mile away that c172 is how big - well 6' tall object 2600' away your scan needs to be every 0.132 degrees to reliably catch it (and 6' is pretty optimistic isn't it? will it catch the LG?) how long does it take to sweep lidar across 360degrees at 0.132 resolution?...
 

Vigilant1

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The long-range Waymo lidar is good out to a few hundred yards today, depending on the reflectivity of the target object. Sensitivity and resolution will depend largely on processing power, and nothing is improving as fast as processing power. So, it is not cheap or sufficiently fast now, but in a few years... This technology will be getting a lot of attention, esp when Elon finally concludes that his autonomous car dreams can't happen without lidar.
 

Aesquire

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It seems your ideal is a VR system that allows you to look through the structure of the plane and your own body to see 360 x 360. Preferably in 9K ultra high rez. And a microwave detection system that can pick up the reflection of the background radiation of the universe on any metallic object to give warning of impending collision. Something that makes the F-35 system look like a child's toy, has zero detectable emissions, and, to be perfect, use portable batteries so you don't have to have an electrical system onboard and can save the money on transponder gear.

Sounds great!

However, belly windows are too hard?
 

BJC

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What's "standard" approach angle for a, say, RV-7 or a C-172? Typical airport, U. S. ?
Per the FAA, 3 degrees is standard for a PAPI. Note the following:
c. Glide Path Angle. For utility runways without jet aircraft operations, the glide path angle may be greater than 3 degrees but not more than 4 degrees for the proper threshold clearance height or obstacle clearance requirements. If an angle greater than 3 degrees is used, it must be specified in a Notice to Airmen (NOTAM) and be published in the Airport Facility Directory.
Many of us fly steeper approaches, because we were taught to be within gliding distance of the runway.

BJC
 

Aerowerx

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Per the FAA, 3 degrees is standard for a PAPI. Note the following:


Many of us fly steeper approaches, because we were taught to be within gliding distance of the runway.

BJC
Or there was a hill a mile off the end of the runway.
 
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