Double floatplane crash Ketchikan

Roger Roger

Paid to sleep, fly for fun
Does adsb show non-adsb equipped aircraft?
Only if they are showing on TIS-B and the adsb aircraft is in range of a ground station.

Not relevant in this case because practically all the 135 aircraft down there are equipped, including the two accidents aircraft.

Whether it is always turned on and functioning properly, I can’t speak to.
 

knot4u

Repeat Offender
Do most small aircraft not have TCAS? I know some do, but is it rare and something that would be way too expensive for these types of operators?
 

BobDDuck

Island Bus Driver
Do most small aircraft not have TCAS? I know some do, but is it rare and something that would be way too expensive for these types of operators?
Most GA aircraft do not have TCAS. Some do have TIS which just shows nearby transponders reacting to interrogation pings from ATC radar. ADSB-in (in those aircraft that have it) shows nearby adsb-out targets plus transponders picked up and retransmitted by a ground station, if there is one nearby.
 

knot4u

Repeat Offender
Most GA aircraft do not have TCAS. Some do have TIS which just shows nearby transponders reacting to interrogation pings from ATC radar. ADSB-in (in those aircraft that have it) shows nearby adsb-out targets plus transponders picked up and retransmitted by a ground station, if there is one nearby.
I looked up the cost after I posted, makes sense that a lot of GA aircraft wouldn't have it. I wonder if I mistook TIS for TCAS in some small GA airplanes I've flown in. Hopefully once the ADS-B mandate has been implemented these sorts of things will be far less frequent, but as @Roger Roger points out sometimes people do weird things for odd reasons and sometimes stuff breaks so I doubt it will never happen again.
 

Fixtur

Prefamulated Amulite
Having taught and flown aerial tours in a number of TIS-equipped airplanes. It’s saved my bacon a few times at busier un-towered airports where someone hasn’t figured out how to use a two-way radio.

It’s also surprised me in areas of spotty ADSB tower coverage (south of KHAF below the bravo in this case), where one second there’s nothing on the box and two minutes later demonstrating slow flight you get an alert and another skyhawk zooms 300 feet overhead.

Moral of the story - it’s a wonderful tool, but only an augmentation to “see and avoid”, not a replacement.

Fix, happy to be in the flight levels now, Fix.
 

Roger Roger

Paid to sleep, fly for fun
Having taught and flown aerial tours in a number of TIS-equipped airplanes. It’s saved my bacon a few times at busier un-towered airports where someone hasn’t figured out how to use a two-way radio.

It’s also surprised me in areas of spotty ADSB tower coverage (south of KHAF below the bravo in this case), where one second there’s nothing on the box and two minutes later demonstrating slow flight you get an alert and another skyhawk zooms 300 feet overhead.

Moral of the story - it’s a wonderful tool, but only an augmentation to “see and avoid”, not a replacement.

Fix, happy to be in the flight levels now, Fix.
If both aircraft are equipped with functional and operating ADSB (as the aircraft in this crash supposedly were) dead spots from towers do not matter.
 

z987k

Well-Known Member
If both aircraft are equipped with functional and operating ADSB (as the aircraft in this crash supposedly were) dead spots from towers do not matter.
Depends if they're on 1090 or 978.

If they're UAT only that's not true.
 

Capt. Chaos

Well-Known Member
Both were 978 equipped, the Otter had traffic displayed on the EFIS and the Beaver on iPad. Dam shame, Randy was was good guy.
 

z987k

Well-Known Member
What? 978-978 works and 1090-1090 works. You only need a ground station for 978-1090.
978 will stop broadcasting after a period of time if the transponder isn't interrogated within that period of time.

If you have two people outside radar for enough time 978 won't be broadcasting and they won't see each other. I was just discussing this problem with the uavionix tech at the airmen's show.
 

Capt. Chaos

Well-Known Member
978 will stop broadcasting after a period of time if the transponder isn't interrogated within that period of time.

If you have two people outside radar for enough time 978 won't be broadcasting and they won't see each other. I was just discussing this problem with the uavionix tech at the airmen's show.
Incorrect. 978 broadcasts at 1 second intervals irregardless of transponder interrogation or radar coverage. 95% of all 978 installs in Southeast are in planes with no accompanying transponder, just a UAT control head and there is no radar coverage anywhere in most of Southeast at a altitude a floatplane operates at.
 

z987k

Well-Known Member
Incorrect. 978 broadcasts at 1 second intervals irregardless of transponder interrogation or radar coverage. 95% of all 978 installs in Southeast are in planes with no accompanying transponder, just a UAT control head and there is no radar coverage anywhere in most of Southeast at a altitude a floatplane operates at.
Wow, I'd never heard of people installing ADS-B but choosing to still not be 2020 compliant. Bravo Alaskans!

The 1 second interval is not a requirement, and most equipment I've looked at stops doing it when it doesn't have a mode A source. I was unaware there were any installations that would even function without at least a mode A source, as then you're not in compliance with the FAR for ADS-B airspace.

Further, the altitude reported from ADS-B is supposed to be from a baro source, not GPS. Which is why every installation I've seen takes this from a serial from the transponder, or is sniffing the mode C. I guess if you had an encoder that gave the right serial out that could work. Or just have it set up to report it's GPS altitude since you don't care about the requirements anyways.
 
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Roger Roger

Paid to sleep, fly for fun
Wow, I'd never heard of people installing ADS-B but choosing to still not be 2020 compliant. Bravo Alaskans!

The 1 second interval is not a requirement, and most equipment I've looked at stops doing it when it doesn't have a mode A source. I was unaware there were any installations that would even function without at least a mode A source, as then you're not in compliance with the FAR for ADS-B airspace.

Further, the altitude reported from ADS-B is supposed to be from a baro source, not GPS. Which is why every installation I've seen takes this from a serial from the transponder, or is sniffing the mode C.
With all due respect, you don’t know what you’re talking about. The non-transponder installs use a control head that looks like a transponder and either an encoder integral to the head or a separate one just like many xponders. I know from extensive experience that aircraft to aircraft works just fine in absence of a ground station. Every trip to Skagway....
 

z987k

Well-Known Member
With all due respect, you don’t know what you’re talking about. The non-transponder installs use a control head that looks like a transponder and either an encoder integral to the head or a separate one just like many xponders. I know from extensive experience that aircraft to aircraft works just fine in absence of a ground station. Every trip to Skagway....
I don't think you're aware of how a lot of the different UAT vendor's products work. That may be true of the manufacturer you guys down in SE found that would do a non ADS-B compliant ADS-B installation(It's the dumbest thing I've heard of in forever). All of the sniffing UAT installations stop reporting once they can't sniff mode C, which transponders don't broadcast unless interrogated. Every vendor I've talked to didn't re-write the code for their other products. If the transponder isn't doing anything, then the ADS-B box stops reporting.
To be sure we're talking exclusively about UAT here, not 1090, which is completely different.
 

Capt. Chaos

Well-Known Member
I don't think you're aware of how a lot of the different UAT vendor's products work. That may be true of the manufacturer you guys down in SE found that would do a non ADS-B compliant ADS-B installation(It's the dumbest thing I've heard of in forever). All of the sniffing UAT installations stop reporting once they can't sniff mode C, which transponders don't broadcast unless interrogated. Every vendor I've talked to didn't re-write the code for their other products. If the transponder isn't doing anything, then the ADS-B box stops reporting.
To be sure we're talking exclusively about UAT here, not 1090, which is completely different.
First off, all the ADS-B installs were done by the FAA as part of the original Capstone test project. There is no rule airspace anywhere in Alaska for VFR aircraft other than Anchorage. So all the of VFR aircraft here were given a UAT and a custom built GSL71 UAT control head. All done again by the FAA. Even in our IFR aircraft the UAT takes wired data from the transponder and altitude encoder, and is not depended on any interrogation by the transponder.

The original MOPS for ADS-B didn't allow for anything like Uavionix's system, they were actually given a cease and desist letter from the FAA when they first started trying to sell it. Pressure from the GA groups, as well as the FAA realizing it was better to have these low cost ADS-B work a rounds than people doing nothing and the rules were changed to allow the wing light sniffer type stuff. Uavonix started as a ADS-B hack and didn't meet the orignal ADS-B rules.
 

Cherokee_Cruiser

Well-Known Member
When I did my Ketchikan cruise air tour in 2015, my #1 concern was the fact that there were just way too many planes operating in that window of when the cruise ship is there. We docked in the morning and set sail by the evening (5pm I think). Everything has to happen in that window. Honestly a midair here was inevitable.

I like how the NTSB is gonna investigate. Sure, go ahead. But I give you their standard midair probably cause: "the failure of the pilots to see and avoid each other in VFR........."

The same line they've used for decades which hasn't done jack to prevent midairs.
 

Capt. Chaos

Well-Known Member
When I did my Ketchikan cruise air tour in 2015, my #1 concern was the fact that there were just way too many planes operating in that window of when the cruise ship is there. We docked in the morning and set sail by the evening (5pm I think). Everything has to happen in that window. Honestly a midair here was inevitable.

I like how the NTSB is gonna investigate. Sure, go ahead. But I give you their standard midair probably cause: "the failure of the pilots to see and avoid each other in VFR........."

The same line they've used for decades which hasn't done jack to prevent midairs.
What sets this one apart is both airplanes were equipped to prevent this very thing from happening.

As have been the last 6 fatal crashes in Southeast Alaska (not including the Guardian accident). I know there are folks in the FAA and NTSB that are taking a hard look at why after the introduction of the Capstone program there were no CFIT or mid-air's for a decade and all of the sudden these same aircraft are being piled up all over in the Tongass.
 
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