anyone ever try try fishing boat depth finder in there plane? couple things, in the opps darn it, always reading about planes flying into a hill, some of these depth finders are accurate to the foot at a pretty good clip, and when flaring to land thought it would be interesting to see how it works. thinking they should work through fog or rain or darkness. lot of them are very accurate down hundreds of feet. just a thought????
depth finder
- Thread starter tempdoug
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mvivion
SPONSOR
Bozeman,MT
They operate on the principal of sonar. Sound is transmitted and then the receiver “listens” for an echo. Water is dense, so sound transmits through water well. Air, not as well, but the big problem is the air/water interface, which reflects the signal.
I operated a Cessna 206 for several year that had a depth finder installed in one float. It worked fine, as long as the plane was on the water, and accurately measured water depth.
What you’re talking about would be a radar altimeter, which measures height above ground.
MTV
I operated a Cessna 206 for several year that had a depth finder installed in one float. It worked fine, as long as the plane was on the water, and accurately measured water depth.
What you’re talking about would be a radar altimeter, which measures height above ground.
MTV
Gordon Misch
MEMBER
Toledo, Wa (KTDO)
That, and - - Which direction is it "looking"?
If looking down, it won't give any info about that big rock out in front - - -
And if looking forward, that canyon out front might not be illustrative of the antenna wires 10 ft ahead.
Yikes!
If looking down, it won't give any info about that big rock out in front - - -
And if looking forward, that canyon out front might not be illustrative of the antenna wires 10 ft ahead.
Yikes!
BC12D-4-85
SPONSOR
Fairbanks, AK.
The depthfinder's utility is aquatic when landing on shallow lakes or rivers with turbid water. Turn it on, touch down, check depth before falling off the step. Kept me alive for years especially on Alaska's windy North Slope. But they can fail on contact if the plane's static charged and the transducer takes a hit. Rare but happens.
Gary
Gary
skywagon8a
MEMBER
SE Mass MA6
What mam90 and farmboy said. I used one for years. It only looks at what is directly under you so would be too late to avoid an obstacle. It will show the depth trends so that you can make proper judgement whether to continue or not. It is NOT reliable when on the step as there is not always solid water for it to "look" through. The turbulent water/air bubbles makes the unusable. Also it is not accurate on muddy bottoms.
mvivion
SPONSOR
Bozeman,MT
My transducer was mounted just fwd. of the step, and worked fine in almost all situations. Our maintenance geniuses first mounted it just behind the step, and that’s where you run into problems with air. As I noted, sonar doesn’t do well with air/water interface.
MTV
BC12D-4-85
SPONSOR
Fairbanks, AK.
As MTV notes mounting forward of the step reduced interference from entrained air. My ride had it mounted in the inboard upper scalloped portion of EDO 3430's. The idea was to avoid damage when parked from gravel and that proved to be the case for 20 years. But...then there's always the "water rudders which flip up and make noise when extended in shallow water" technique. Or, make a water pass and return to look for two dark mud tracks from a soft bottom. All part of the job.
Gary
Gary
Last summer I installed a new fancy fish finder on a customer's boat, it read the distance to ground while on the trailer when I powered it up, I could also see my feet when I walked around the back of the boat.
Obviously this was short distance with no water/ air interface.
Obviously this was short distance with no water/ air interface.
BC12D-4-85
SPONSOR
Fairbanks, AK.
A fathometer can awaken above the water. The display will change (mine was digital) but the actual distance may not reflect reality. The speed of sound in air vs water etc. But it has some utility if needed.
Gary
Gary
There are used radar altimeter systems and parts on eBay. They put out distance in hundreds of feet, so they are no good for landing. They are ancient, expensive and they all look heavy as can be.
I made a little rechargeable electronic altimeter for pattern work that is accurate to the foot. I can set it on the ground to "zero AGL" or exactly at pattern altitude at "1000 AGL" and then it gives me a readout of the exact altitude above the touchdown point as I climb or descend. I like to check out my AGL altitude as I make the base and final turns. This has helped me with my sight picture understanding in my Super Cub. Only problem is, when I am in the flare I am not interested in looking at the display!
But it might be cool for another hobby project to modify a laser ruler to audibly call out distance from the wheels to the ground for the last 20 feet in the flare .
https://www.ebay.com/itm/UNI-T-LM50...hash=item2f35ce9d19:m:mjwIU2bKdWBrn8Ow7UxpbbA
https://www.ebay.com/itm/RS232-TTL-...a=0&pg=2047675&_trksid=p2047675.c100008.m2219
I made a little rechargeable electronic altimeter for pattern work that is accurate to the foot. I can set it on the ground to "zero AGL" or exactly at pattern altitude at "1000 AGL" and then it gives me a readout of the exact altitude above the touchdown point as I climb or descend. I like to check out my AGL altitude as I make the base and final turns. This has helped me with my sight picture understanding in my Super Cub. Only problem is, when I am in the flare I am not interested in looking at the display!
But it might be cool for another hobby project to modify a laser ruler to audibly call out distance from the wheels to the ground for the last 20 feet in the flare .
https://www.ebay.com/itm/UNI-T-LM50...hash=item2f35ce9d19:m:mjwIU2bKdWBrn8Ow7UxpbbA
https://www.ebay.com/itm/RS232-TTL-...a=0&pg=2047675&_trksid=p2047675.c100008.m2219
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BC12D-4-85
SPONSOR
Fairbanks, AK.
That laser rangefinder with voice output is something Ron KL7GB needed years ago when he lived in Fairbanks. Former C-130 pilot during the oil pipeline days in Alaska that lost his vision in a vehicle accident (motorcycle?). He walked all over town with a cane and built his own home with help. He had a wood workshop downstairs. All done in his mind but he needed a voice ruler for special projects but none were available then. It's amazing what he accomplished without one. I helped him build and install radio antennas in trees and he always knew where he was.
Gary
Gary
skeeter.enterprises
Registered User
I've been working on this exact problem for a couple years, and I think I finally have a solution. I've wrapped it into my business Skeeter Enterprises, check out Stadia there. It's a LIDAR that gets mounted to the wing strut and connects with a smartphone to give altitude data. https://skeeterenterprises.com/products
skywagon8a
MEMBER
SE Mass MA6
How well does it work over glassy smooth water?
skeeter.enterprises
Registered User
It depends on the water clarity. Silty/muddy water it seems to do fine. Testing over relatively clear water severely limited it's range, but still worked at smaller distances. I haven't found any crystal clear water to test over, but I suspect in that scenario it wouldn't work well or at all
JWE
FRIEND
NC30
Check out this thread on the FlyHusky website:
http://flyhusky.com/forum/index.php?threads/lidar-altimeter.2698/
http://flyhusky.com/forum/index.php?threads/lidar-altimeter.2698/
skeeter.enterprises
Registered User
Thanks for the link, very interesting. It looks like the main difference is that Stadia has a more powerful LIDAR, doesn't require any modifications to be made to the aircraft, and connects to the users smartphone as opposed to having a dedicated piece of equipment. This is certainly interesting tho, and very similar to my first prototype.
Not real-world useful if connected to smartphone. Have it connect via bluetooth directly to bluetooth capable headphones. Automatically begin audio readouts when descending below 100 feet. "100 - 80 - 60 - 50 - 40 - 30 - 20 - 15 - 10 - 9 - 8 - 7 - 6 - 5 - 4 - 3 - 2 - 1."
A pilot would not turn on a smartphone app, connect to the altimeter, watch it during landing, etc. Especially during a hairy landing, which is when it would be needed.
Use a good high capacity USB rechargeable lithium battery, one that's good for many hours. For battery life, include an altimeter chip and maybe an accelerometer in the electronics. Then go low power mode when ascending and holding altitude. Full power when descending only. Turn off when at no altitude change for more that 10 minutes (i.e. on the ground) or no vibration (i.e. engine off). KISS and make it useful, not a novelty that will not be used in practice. If you get the details right, I would buy one of your LIDAR altimeters!
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skeeter.enterprises
Registered User
You're absolutely right Tennessee, I should clarify:
The smartphone does not need to be be fully on for Stadia to work. When the phone screen is switched off, Stadia still runs in the background. The Stadia app interprets the LIDAR data, and produces audible sounds. So you can connect your bluetooth headphones to your phone, or through an aux cord like with classic David Clarks, and hear the sounds. No need to look at the phone at all, or even have it readily available. I've tested the voice output that counts down the altitude in numbers, but I found that a beeping tone seems to be more popular. I'll probably have both options available in the Stadia app. My dad is partial to the beeping, as he can tell by the change in tone and frequency where he is above the ground without having to really listen. The Stadia app also has a visual readout, but like you said, it's not really useful on final.
I'm glad you brought up the low power mode, because that's something I gave a bit of thought to as well. The Stadia device has enough battery capacity to run the LIDAR full time for 11 hours. But in the app there's an option to put it into Standby mode which turns off the power to the LIDAR. Stadia can run at least 16 hours in Standby mode. The Stadia battery is rechargeable via micro-USB cable. My dad will typically keep Stadia in Standby mode, then before he starts descending for landing he turns it to Active mode. Most of the inspiration comes from him, he does a lot of cub flying in Alaska. If you're interested in getting more information I'm more than happy to help.
skeeter.enterprises
Registered User
Hey, the Stadia LIDAR altimeter is finally ready for me to sell! If you want to check it out there's pictures and video on my webpage https://skeeterenterprises.com/stadia-1
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Scooter7779h
PATRON
Anchorage, Alaska
What a crock. I’m a surveyor that helped develop Optec Lidarvfor ground and near shore bathematry. The idea of having a Lidar in a Cub to judge altitude is just flat out ridiculous. Look out the widow, don’t need dashboard eye candy that isn’t going to have a latency update rate to be worth a ****. If you rally wanted to bury your head in the dash, and likely crash, get a radar altimeter. Cubs are VFR machines, look out the frigging window, it’s not complicated.
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skeeter.enterprises
Registered User
Not sure how you can say that the latency update rate is worth a **** since you've never used it nor asked me any questions about it. This device was originally designed for ski flying when conditions make it difficult to determine the height above the ground visually. Others have since seen other merits to it and seem quite happy with it.
Scooter7779h
PATRON
Anchorage, Alaska
Bury your head in the dash and have a nice day. Do what you want. Been flying Cubs for 47 years, never once did I even think I needed a Lidar. Ridiculous imho, obliviously your enthralled, maybe you need artificial enlightenment. Whatever.
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