There's a story going around in the halls of radio geekdom (the SDR radio monitoring circles) that one of the unidentified objects that the Air Force shot down last week was a ham radio balloon. It's all circumstantial evidence, but that evidence all fits and sounds believable.
First, I need to do a little background information and introduction to the acronym salad that's
inevitable here.
Sending remotely operated or semi-autonomous balloons on otherwise random trips has become another of the hundreds or thousands of sub-hobbies in ham radio. Large amateur radio balloons, carrying more than four pounds that are launched in the USA require FAA clearance, need a radar reflector attached, and usually continually transmit APRS telemetry before naturally popping and falling back to earth after a few hours, just like a weather balloon. APRS in this sense is the Automatic Position Reporting Service that uses what hams refer to as packet radio to transmit a radio's location at regular intervals; because of its dependence on packet radio, you'll see that acronym translated as Automatic Packet Reporting Service.
I'm guessing that because of the FAA requirements for the larger balloons, a sub-sub-hobby got started referred to as pico balloons (literally a billionth of a balloon - but in this case, a small balloon). These are generally the helium-filled, Mylar balloons you might get for a birthday party and carry small, solar-powered payloads that are only a few grams in weight. These can generally be launched from anywhere without FAA approval. What for? Another amateur radio mode that's currently in wide use is called WSPR, for Weak Signal Propagation Reporter.
WSPR was invented to allow stations to transmit a weak signal on recommended
frequencies in any of the different amateur bands so that anyone can see at a
glance if a band they're interested in is "open" to some part of the
world. The transmit power is at the discretion of the operator, so some
guys will send milliwatts and others will send several watts. The idea started as a beacon network, where stations around the world transmitted on a schedule and reported what they heard to the internet. Similarly,
one can transmit a WSPR "ping" from their station and look up what other places heard their ping. A pico balloon can carry a small, low power
transmitter and GPS receiver, with a small solar cell array, and by using
the WSPR network, determine where the balloon is. A well-designed pico
balloon can drift around the world several times and its path mapped. As
you might expect there are clubs
like the NIBBB, where the
hams who want to do this hang out and help each other.
Which brings us to what may be the News Story of the Year:
There is speculation that at least one of the objects shot down over Canada, Yukon by a US Air Force jet may have been amateur radio pico balloon K9YO-15 which was launched from Illinois on October 10 2022. It was on its seventh circumnavigation of the globe after being aloft for 123 days.
What RTL-SDR reports is that this was a silver mylar 32" spherical balloon, similar to or even exactly this one from balloons.online. The payload was a GPS module, Arduino, SI5351 clock generator used as a WSPR and APRS transmitter and a solar panel, all together weighing 16.4 grams.
The K9YO-15 balloon ceased all WSPR telemetry transmissions while flying just below Alaska since Feb 11 00:18 UTC (just before sunset in Alaska when the solar panels would stop working).
By using NOAA wind models and the last known location by Alaska, K9YO-15 was projected to have been over Yukon when the US Air Force shot down the unknown balloon object at Feb 11 20:41 UTC (3:41 PM EST / 1:41 PM Yukon time according to Canadian Defense Minister Anand). Reports put the altitude of the shot down object at approximately 40,000ft (~12000 meters), which matches the projected ~11500 meters of K9YO-15. Based on the previous days transmission times, it is suspected that if it were operational, the balloon would have begun transmitting again sometime later in the Yukon afternoon when the sun was stronger, but no transmissions have been seen.
The last reported position from K9YO-15 is indicated by the yellow
triangle, with the projected path shown. The balloon was at the black star,
closest to an uninhabited Alaskan island called Hagemeister island,
when this forecast path was created.
The yellow star works out to be around the Yukon cities of Dawson City and
Mayo. The area is being searched, but nothing has been found. It's
a big area and the K9YO-15 balloon is small; if it was blown up by some sort
of weapon, the debris is going to be even smaller than that 36" balloon linked
to above. Over on Twitter,
@ikluft
(KO6YQ) reported on this speculation, and kept monitoring for K9YO-15 for
several days. Yesterday, he tweeted that while the balloon hadn't been
heard for days, that's not unexpected in the long, dark winter nights of the arctic. The NIBBB club officially lists the balloon as "missing in action."
There's a mental picture that goes with this all; a handful of ham radio pico balloons around the world getting tracked down by the most advanced militaries in the world and shot out of the sky. Reading around shows a cost for these missions to take out a $50 ham project as between 1 and $2 million. Burning that as dollar bills would be more useful; at least you could get warmed by the fire or make some coffee or something.
at least the USAF is getting some target practice, even if it doesn't shoot back
ReplyDeleteIf it turns out that the AF shot it down I sure hope the pilot was under orders to take it down. Having a pilot with decision making skills that are so poor as to make shooting down a mylar radio balloon on his own authority seem like a good idea is somewhat frightening to me. Cost seems like it is in the ballpark. Four hundred thousand for an AIM 9X if that is what they used. It is IR but does have a very good proximity fuse. Then throw in $70K per hour for the F 22 and some more for a tanker plus whatever other aircraft where up there. This has got to be embarrassing as heck for the aircrews. EdC
ReplyDeleteAre we sure Raytheon isn't sending the balloons up?
ReplyDeleteNo word yet on how many scrambles from Nellis every time some kid in Anaheim loses their mouse-eared balloon.
ReplyDeletetouche.
DeleteI expect DHS to designate hams as a terrorist organization (with world-wide affiliates) any moment now. The entire Callbook will be placed on the 'no-fly' list. Any vehicle with a Larsen or callsign tag gets a felony stop by law enforcement. If you don't hide that triband yagi you risk a swat raid or a Hellfire missile.
ReplyDeleteOutside the ham radio community who knew about these? No license required and fairly small. Are their projected tracks and altitudes provided to FAA? 40000ft is prime altitude for airliners and biz jets..
DeleteSo no one in the administration would have a clue what they are, they wouldn't know who to ask because they are inept, and the size and altitude make them a potential risk to air traffic And it's the great balloon panic of 2023 so "Do something.....do anything!"
I had no idea about those pico balloons, so I'll SWAG the wider ham community doesn't know about them, either. The people who play with them are a tiny fraction of the ham community.
DeleteMy way to look at this is to figure "cubic feet of balloon per cubic mile of airspace" as a crude way to figure out what the chances of an airplane hitting them would be. Looking at that one website (NIBBB) and the others they link to, I'd hazard a guess that there's less than 100 of these balloons flying at any time. As far as I can tell it's being exceptionally generous to go with 100. One of those balloons is a "couple of" cubic feet (for 18" by 6" thick, that's 3-1/2 cubic feet). A mile contains 147,197,952,000 cubic feet (147.2 billion cubic feet).
Don't forget every one of those airplanes has engines on it that has to pass a test of having a bird shot into it to simulate ingesting birds on take off or landing. The bird is a far tougher test than a Mylar balloon. The bird, after all, is essentially water, which isn't compressible, and the balloon is very thin plastic surrounding helium.
Thanks for the write-up. I clicked through on one QRZ forum post from my news feed about it, but just the first page was so full of typical web-forum trash posting, that I just closed the tab. Getting good information... nah, no such luck.
DeleteI"ve been aware of only a little of the ham balloon stuff - definitely not the tiny ones.
As far as the cost goes, well, the flight hours, etc. could just go towards the required min. time to keep up proficiency, i.e. they'd fly them anyway as training otherwise. They do expend live missiles against training drones.
Made me think of an old story about the chicken gun test. IIRC, it was for windshields not engines, but anyway, the punch line was the operator didn't know he was supposed to thaw the chicken first.
I worked with a guy 30-ish years ago who swore he was there when it happened. This would have been at Pratt & Whitney in Vero Beach, the next bigger city down the coast. (AFAIK, they've since moved the engine test range down to Palm Beach county, more like 100 miles down the coast). Of course, I have no idea if he was really there or if it was just another retelling of that story.
DeleteIngesting small flying birds might be less of a problem than ingesting mylar and the small amount of other material in the balloons, as the blades are very carefully balanced. As the pieces of the balloon are ingested further into the engine, the increased temperature could cause thin film residues that will adhere to the blades and other parts of the engine. I worked several designer and tech writing contracts with a major US engine vendor, and the modern engines are not as robust as those from, say 30 years ago. I saw a video of a regular six sided dice that was ingested into an engine as part of a test. Not good, and I can only imagine what my D&D 20 sided dice would do...
ReplyDeleteThe pilots commented that they couldn't see their targets visually, but of course the radar picked them up - which speaks to a corner reflector for all of us who understand basic radar principles. The FAA requires them so modern commercial aircraft don't blunder into them.
ReplyDeleteI certainly don't expect a POLITICIAN to understand this stuff, but wouldn't you think the higher-ups in the Military would at least have a passing knowledge of this sort of thing? Not really, they are political animals also.
And so it goes.
A buddy I helped get started in ham radio flies these. I think he was the 7th ham to have a balloon circumnavigate. We used to launch them off the roof of our office building at the U. His were usually one or two mylar party balloons filled just enough helium to float at around 40,000 feet to get the most of the jetstream. He custom designed and built his transmitter which can do either APRS or WSPR depending on the area. The CPU that controls it has geofencing rules to keep it from transmitting in countries that forbid it. The antenna is a piece of yak hair wire 1/4 wave hanging below. Power is a couple of solar cells and a supercap. The whole thing weighs ounces, well under a pound. I would not sweat running into it with my Aeronca Champ. A turbine that can eat a ramp worker would never even notice it. He lost a couple of them during their dark periods in the mid east. We used to joke that they ended up coming home draped over the wing of a reaper drone. Who knew?
ReplyDeleteThese are often flown as part of a school project - get the kids at a junior high or high school to participate in the building and planning and launch and tracking. Good STEM project. There are folks who have learned to make really good, optimized, balloon envelopes, that are so good that they often manage to stay aloft long enough to circumnavigate several times before having an issue or running into weather.
If TPTB were interested, I suspect they could get the tracking URLs for most all of these balloons for mission planning purposes. Most of the balloonists publish theirs so their fans can follow along.
Bill Brown WB8ELK of 73 fame got very big into this and I think has a pretty good web page about it all
We've launched several from schools and hamfests. I think my buddy has launched about 20 so far with at least one circumnavigation and probably more since I was directly involved. He also does High Altitude Balloon launches which typically use a more normal weather balloon rather than a pico, which take about 3 hours to go up to around 100kft and back down. Those have to weigh under six pounds, have a radar reflector, parachute and often have cameras, multiple transmitters, once a cross band repeater, and end in a fox hunt trying to find and recover the balloon after landing. We sometimes help with that by car or Champ. APRS usually falls off the networked receivers below about 2000' so unless we are close enough to hear it all the way down (usually lands more than an hours drive away) it gets interesting trying to find it. Often it lands in a tree which helps by making the APRS beacons able to be heard further but the you have to deal with the tree.
All in all a lot of fun stuff. I hope TPTB don't ruin it by banning the balloon stuff. Of course that won't affect the folks other places that do it...
The thing that gets me is that the military is supposed to have really good sigint. You can't tell me that they can't pick up the signals those balloons are transmitting. And all of the communications protocols are open source by the codes that regulate the HAM airways. They had to be getting the balloon's ID, and it's not hard to track what it is with that.
ReplyDeleteSo. Are the commanders ordering these shot down stupid? Paranoid? Cavalier? Spiteful? Negligent? None of those sounds like a good option to me, and I can't really think of any others.
Can I do multiple choice? If not the answer is Stupid. If so, add cavalier and negligent.
DeleteWhile I'm certain the balloons have radios on them that the military can monitor, it's also one weak signal in the "DC to Daylight" span to find, at the right time (when it's transmitting), decode and track to the source.
Those systems are low power - they've given up batteries to just charge a large capacitor. The trade off is they can't transmit when the solar panels don't allow. They transmit intermittently, probably in parts of the HF spectrum that the military never listens to. They don't know those pico balloons are up there to even try to monitor.
Add in a little cavalier attitude, anxious "just do something" imperatives from the top brass, and this is what you get.
My friend's balloons typically transmit about 10mw on 20 meters WSPR when the solar cells are getting enough sun to charge the supercap, into an end fed antenna. When it's over areas that support APRS like CONUS it switches modes to APRS which has more receivers and support. The received data from either mode is collected and available on servers like APRS.fi.
ReplyDeleteIf the defense folks weren't aware of those resources hopefully they are now where they can easily keep track.
Of course Congress is in 'do something even if it's wrong and counterproductive' mode and is talking about making the balloons carry ADS-B which is a non starter. A far better solution would be to link the ADS-B servers to the APRS servers to share the APRS data into the ads-b data stream. One hopes cooler heads prevail.
I do HOPE that the Feds aren't so stupid as to try to take on the ham community. NASA is solidly on our side. Many former military are hams, whether active or not (some just pick up the license after their service, but don't use it).
ReplyDeleteThe ISS Contact program, in conjunction with ARRL, has been wildly popular with the public.
There are currently about 3/4 of a million currently licensed hams out there. The ARRL has a nice war chest for defending the radio spectrum from encroachment by the cellular network companies. They could easily move some of that money to protection of the amateurs' right to launch small balloons.
Linda Fox, KM4GSF
I think it was more ignorance or stupidity than an attack on ham radio. The balloon is transmitting at QRPp levels, as CNYguy said, and while the military can undoubtedly monitor HF, I doubt they could identify it as coming from the balloon. In fact, the entire time the F-22 (? I think) was following it might have been when the transmitter wasn't even transmitting.
DeleteWhen dealing with the government, stupidity is always a reasonable first guess, right?
Either stupidity or malice. It's rampaging congresscritters who are looking to 'do something' that are apparently the proximate threat.
ReplyDeleteThe military can monitor hf no doubt. But they don't need to. The balloonists make their tracking data public online. You get a ufo report, check it's position against the balloons being tracked. Easy peasy.