A F-35 is in Mode S over Europe

https://globe.adsbexchange.com/?icao=af351f

Now this is a real treat, a F-35 near a active conflict is openly broadcasting.

 

coincidentally, this is the SAME F-35 i have caught twice opening squawking 7700 while Stateside

 

I noticed on 3-2 it went across the states back and forth but the long journey the tracks are dashed lines the whole way. could it have been encrypted for the long stretch and then back to MLAT for the short manuevers?

 

if it was in Mode 5 there would be no track at all.

 

what explains why none of the feeders got signal on it between AZ and the east coast and back? it was mostly dashed likes like it wasn't being picked up?

 

so AF351F is the same code for every F35 in the US Inventory?

 

@CapStar362 did you see my question?

 

and the answer is the post before it.

we cannot interrogate a Mode 5 transponder, we do not have the cypher codes to do so and Mode 5 is full duplex encryption. Encrypted Interrogation and Encrypted Response.

Mode 5 is basically Mode S just fully encrypted. and backed by a multitude of international laws for even attempting to decrypt the codes needed to interrogate and recieve a transponder in mode 5.

 

that still doesn't answer my question. Why was the tracks across the states dashed lines? Why wasn't it picked up by the feeders? You said if it was encrypted there wouldn't be a track at all. But why didn't the feeders pick up on the long tracks making it dashed lines?

 

dash lines indicate poor to no reception and is a estimated plot, that is if im re-reading @wiedehopf 's FAQ correctly.

the dashed lines means it was not picked up or the data was in such poor reception that the data was garbled and corrupted.

we cannot interrogate a Mode 5 Transponder, that's why. its a federal crime and international crime to do so.

So if said F-35 was in Mode S ( Sierra ) , in open civilian broadcasting, then went to Mode 5 ( Five ) for some time, it would vanish from civilian receivers. If it goes BACK to Mode S ( Sierra ) during that same flight, at least how I'm interpreting this is, the dash line just is a guess of where and how the F-35 traveled. since it did not have the actual data, it made a guess.

so yes, i did answer your question. Unless we are in a FAA Tower or in a DOD Tower, we CANNOT see a Mode 5 ( Five ) Transponder PERIOD.

 

@eccentric-eric

perfect example

https://globe.adsbexchange.com/?ica...4.5&showTrace=2022-03-12&timestamp=1647063966

Notice how you can click on the history here where the line is solid? Because receivers have the actual data, now, try to click a dashed line.......oops, cant do that. because the data is not there, its a guesstimate of the actual flight path taken.

understand it now?

 

Thanks That's what i wanted to know about the dashed lines. I wondered if that's what happened. So i guess they can change the modes on the fly no pun intended. I wonder why they would change back and forth at this rate? Another question i have is, Is MLAT harder to pick up by the feeders? I often see such jagged dashed lines that go all over the place. I once watched a tanker on a Refuel track going east and had a solid track and i watched the turn just fine as the aircraft turned all the way around, then all a sudden the track that showed the turn disappeared and then the dashed lines appeared for about 50 miles going back west. I dont' know if there was bad reception or if it went to Mode 5. since it had good reception on the same track going east then dashed lines going back the same track makes me wonder if for whatever reason they went to mode 5. another thought would be if a fighter jet in mode 5 showed up to the tanker, the tanker went mode 5 as well.

 

no, when it does that erratic stuff, its low detection with errors and corruption

 

so MLAT is harder to receive from the feeders? If so why is it? Do they not send out as many packets of data? I know with ATCS Monitor some protocols don't transmit data as often so if you miss it you miss it. regular ATCS transmits every minute or every change that takes place and it repeats all data not just part of it.

 

The problem is that each MLAT aircraft needs at least four feeders to receive its Mode S packets in order for ADSBX to calculate its position. So in a sparse feeder area there will simply be not enough feeders.

Aircraft altitude has a big effect on the number of feeders - at 30,000 feet I can receive from aircraft over 100 miles away; at 2,000 feet it is around 10 miles.

 

thanks for the info. I've wondered. I'm aware altitude matters. Just wasn't sure the exact range. When i used to do ham radio sometimes i would get to talk to someone using ham radio on 2 meters in an airplane and I could talk for over a hundred miles just with my hand held radio at 5 watts. not sure the altitude. sometimes people launch weather balloons with a handheld radio doing a simplex repeater attached and people can talk hundreds of miles away. but it's hard to get in there as there is so many people trying to get in.

 

i'm sitting up on a hill a bit and my antenna is situated at the highest point of my roof which pokes up just over the tree line by about 20 feet. ive picked up aircraft south of me towards Atlanta on my receiver as low as 2000 feet but much further away at around 15-20 miles. up high over 150-200 miles away. i've detected high level aircraft as far away from me as almost Valdosta GA which is down at the GA/FL State Line. thats pretty much across the state for me.

my server hosts the receiver's internal viewpoint so i do check it every now and then for any errors and messages. but the receiver itself is in a self contained chassis with its own vent and air supply up in the very peak corner of my attic. ran the coax cable through the attic vent and sealed it from the environment, and the stick itself sticks out and above the roof peak. but its hard to spot unless you are looking for it and my HOA doesn't even know its there

A proper setup is always key also to high reliability if you are in a sparsely covered area, that helps others. im not allowed to run a pole on my home due to HOA ( bleh gag PUKE ) but one day when i get a new property WITHOUT a HOA, i will run a properly rated pole and the antenna much higher. i'm also going to build a lightning detector as well to feed blitzortung and windy apps.

 

what is the typical range on low altitude aircraft? I don't get nothing around Emporia KS below 3,000ft. so i can't see the helicopters. Everything drops off 30 miles east and about 60miles SW towards Wichita. The first picture shows that over 4,000ft the reception is better in my area.

 

That's not inconsistent with what I get. 4000ft to 2000ft makes a big difference, and below 2000ft the range continues to drop off quickly. It also seems to depend on the plane - some planes come into view further away than others in a given direction.

But comparisons are difficult as I am near a range of hills (UK) so I have a limited view of the sky in some directions. And my antenna is just a stick in front of an upstairs window looking away from the hills as I too am restricted by what I can put on the outside of my house.

I have wondered if helicopters are worse than planes for reception because of rotating metal blades right by their transmitter, but I have not seen any evidence to suggest that. I guess the transmitter transmits downwards and blades are above!