Podcast: Hot Air Or High Tech? China’s Spy Balloon

Listen in as Aviation Week editors discuss a week of high drama, including the shootdown of China's balloon and the future of high-altitude surveillance platforms.

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Joe Anselmo:

Welcome to Aviation Week's Check 6 Podcast. I'm Joe Anselmo, Editorial Director. An overflight of the continental United States by an uncrewed Chinese spy balloon and its shootdown off the coast of South Carolina, have generated a furor in the U.S. and raised many questions. Why would China invade another nation's airspace with an airship when it has spy satellites at its disposal? How extensive is China's spy balloon program? Why were earlier over flights of U.S. territory by Chinese airships missed? And was the F-22 shoot-down of the balloon as easy as it looked on television?

Joining me to delve into those questions and more are three Aviation Week editors: Senior Defense Editor Steve Trimble, Executive Editor for Technology, Graham Warwick, and Pentagon Editor Brian Everstine.

Steve, let's start with you. You've just written a detailed analysis for the Aviation Week Intelligence Network that reveals this certainly isn't a one-off incident, but part of a years-long series of Chinese spy missions using balloons all over the world.

Steve Trimble:

Well, there's a few takeaways from this whole episode, this saga, if you will, of this balloon coming across our airspace. We learned some big things. First, and probably foremost is that China has been waging, apparently, a high altitude balloon spying campaign, not just over the U.S. but all over the world, that there had been previous incursions of U.S. airspace by these balloons that we actually just weren't aware of until they went back and checked the forensics of the data they already had with the characteristics of this balloon that they knew and realized that they were seeing the same things. But these same balloons have been spotted before over Japan and Taiwan on multiple occasions, photographed just like they were here just last week. And there's a balloon now floating over Latin America.

It's all a bit baffling. As you mentioned, China has over 250 surveillance satellites somewhere in orbit, many of which that cross the United States every hour, every day. They have sophisticated payloads, you can look up the public information on the Yaogan series satellites, and the Xi'an series satellites, and these are pretty sophisticated things. What the high altitude balloon contributes to that overall surveillance collection is not clear at all at this point. Clearly China sees some value in it, but I'm sure that's going to be analyzed and evaluated.

In the meantime, we learned a couple other things. First of all, that balloon that the Chinese floated across the U.S. is pretty impressive. We've been trying to do these sorts of things, these ultra-long endurance, high altitude balloons for a long time, both commercially and with the military, and some have been more successful than others. Loon was probably a good example of a mixed success story, but that project's been canceled for a couple years now.

But this balloon was different than all of the others that we've seen before in the sense that it still used what appeared to be that super pressure pumpkin-shaped envelope, helium envelope, that we've seen with other types of this kind of ultra- long endurance balloon. But it had, instead of having this translucent fabric in the envelope, it had an opaque envelope. And that's pretty important, because it means that they figured out a way to reflect the energy from the sun away from the balloon so that the solar energy didn't go into the helium inside the gas bag, increase the temperature of that helium, which increases the pressure, which then causes the balloon to explode. That's why all the previous balloons we've seen this have been translucent at those altitudes and for those durations to allow that solar energy to pass through the balloon and minimize the amount of heat that gets created within the helium structure itself.

So, for them to be able to figure out how to do that, and keep the overall weight of that structure, that fabric structure down to a point where they can still have a useful payload and it looked like they had a pretty substantial payload, is an impressive achievement that people are going to try to be figuring out, especially in the high altitude balloon community. So those are two of the big things I've learned about what the Chinese have been doing, but with a lot more to learn as more information comes out.

Joe Anselmo:

Graham Warwick, let's look at this from a technology point of view. I mean, what intelligence can a balloon offer that you can't glean from a spy satellite?

Graham Warwick:

Well, there's been a lot of increased interest in using high altitude platforms, balloons and unmanned aircraft, in the last five to 10 years. The reason is that they fly at lower altitudes than satellites, which means that the payloads they carry, if they're imaging sensors, they have higher resolution because they're closer to the ground, or if they're a communications payload, they have lower latency because they're closer to the ground. So when folks are looking at really detailed earth imaging for crop analysis or ice depth, whatever you want to measure, your sensors are more accurate. And then if you are a flying cell tower, which is one of the big missions they're looking at for these things, your area of coverage and this quality of service that you provide within that area could be greater.

Also, its persistence versus a satellite. A satellite passes over, so you've got a period of time while it goes over. If you can control the balloon, then it can stay over a period of time. And this was demonstrated by Google's Loon project, which basically positioned a flying cell tower over Puerto Rico after the hurricane hit, and it basically orbited Puerto Rico for quite some time, restoring cell coverage. So if you can control it, you can stay in one place. You might not want to do that over the U.S., but you can do it.

And then another thing is cost to launch, because compared to the satellite, basically you can put these things essentially on the back of a truck and move them to wherever you want to launch them from it. Loon actually developed a very, very sophisticated automated launch system where they basically fire these things into the air like pellets, and then they just did their thing.

And as I say, the two main missions that people have been looking at are telecommunications, earth imaging, things like that, civil applications. You're inside the atmosphere, so the issues with it are fundamentally control. That's why it seems a bit of a weird thing to do for surveillance, because there's only a limited amount of control that you have over a balloon once you launch it. Now, what Loon did was, using artificial intelligence algorithms they became very sophisticated at adjusting the balloon's altitude so that if you go up and into a different wind direction, the balloon will go a different direction, you go down into a different wind direction, you go in another direction. They were really sophisticated at mapping the weather patterns and working out flight paths that would keep the balloon on essentially whatever track they wanted just by continuously adjusting its altitude.

Now, Steve can probably tell us to what extent the U.S. says this balloon intentionally changed its altitude to change its direction. I don't know. So, control is one issue. Weather is an issue, not so much at the high altitude because the winds are generally lower at higher altitude, but as we've seen with anybody flying a stratospheric, unmanned aircraft, getting up and down is a nightmare. I mean, you're going through multiple weather systems on the way up, multiple weather systems on the way down. It's very dangerous. We've lost a lot of piles of flying UAVs, balloons maybe, they just get blown around a lot while they're going up and down.

And then the thing that this particular incursion really brings to light is the airspace. Who controls the airspace? Up until now, this is above Class E airspace, this is high altitude airspace above 60,000 feet. It's pretty empty. And if there's anything in it, it tends to be military and it tends to be our military, not somebody else's military. So, it hasn't really been much of a challenge managing that airspace. But with all of these commercial companies looking at using the higher altitudes for commercial missions, telecoms, et cetera, and with this explosion of commercial space activity and vehicles passing through upper atmosphere, either on the way up or the way down -- or in some cases up around and down if you're a Virgin Galactic, something like that -- there has been a move in the last few years to look at how we improve the management of the upper airspace. They call it upper Class E airspace, NASA calls it Extensible ATM, which means that you're taking your current paradigms for air traffic management and then you're trying to extend them above 60,000 feet. That poses a lot of issues for surveillance. How do we know if that anybody's up there? Communications, how do you communicate with them and all that?

So this has been boiling around for a few years, the FAA has an operating concept for higher altitude, Class E airspace, but there hasn't been much urgency behind it. So this may put a bit of a rocket or a balloon up on tackling this issue of how do we surveil and control this upper atmosphere.

Joe Anselmo:

Brian Everstine, I wanted to ask you about the shootdown and how it unfolded. President Biden took a lot of heat for letting the balloon go from Montana all the way to South Carolina before shooting it right off the coast of South Carolina. And at the same time, it seemed the mainstream media just treated it as a given that the U.S. military would just go in and down this balloon. It was way up there, as Graham just said, I mean way, way above commercial air traffic. It wasn't easy to do, was it?

Brian Everstine:

No. And I thought it was pretty interesting to see how this played out. We first learned of the balloon back on February 2nd as it drifted over North Idaho and into Montana. And the Air Force at the time scrambled a couple F-22s out of Nellis Air Force Base, where they're having a red flag exercise, to go get a look at it and start the options of what they were going to do. And that day, President Biden apparently gave the Pentagon the authorization to shoot it down, but top military commanders came back and said they'll want to wait until it drifts out over water. ‘We can take some steps on the ground to cover up the secretive facilities that it might drift over.’ And then as it approached over the coast of Myrtle Beach, we had this made-for-TV spectacle where had F-22s launched out Langley and watched it drift across until finally it went about six miles off the coast, and we saw the AIM-9X shot that just instantly took it down. It looked like it was the easiest thing in the world.

But I'm really wonder wondering how easy that was. I asked General VanHerck, the Commander of NORAD and Northcom about this, about why they went with a Sidewinder, and he basically said he didn't know if this AIM-9X has ever even been tested at this altitude. It was shot at 58,000 feet. The balloon was between 60,000 and 65,000. And if you go back, there was audio of the pilots talking to command and control, and they were authorized for the AIM-9X, but also other ordinance if they needed it. General VanHerck said they went with the AIM-9X as opposed to the AIM-120 AMRAAM because they wanted a shorter range, a smaller warhead, but there was authorization for others. But it was first shot of a Four-Ship of F-22s and it immediately went down. So, it looked easy. But going into this, they didn't even have the data to know if it would work.

Joe Anselmo:

So Steve, in your story, you got into some details also about how the balloon was actually shot down. Do we want to tell our listeners a little bit about that?

Steve Trimble:

Yeah, just to amplify what Brian was saying about the challenge posed of shooting down a hot air balloon, or actually a helium balloon probably, at 60 to 65,000 feet, the big thing is, that's too high for guns. Even if they could use guns, it could take a long time for the helium to actually leak out through any holes. This is a 200-foot tall balloon, any holes you put in it, even with 20 millimeter rounds from a F-22 cannon, it's just going to leak out and it will take several days for the balloon to actually descend to the ground. So that's one issue. So then you have to go to missiles, but then what do you aim at? The helium balloon itself is a void. So even if the missile hits it dead on target, it will just pass through it and there's a potential it won't even fuse and explode.

So what they did of course, was they aimed, it appears, at the superstructure truss below the balloon where they could get a heat return or a heat signature for that imaging infrared seeker on an AIM-9X. And that was apparently enough to do it. But even then, just as Brian mentioned, nobody's tested an AIM-9X at 58,000 feet from an F-22 or any other aircraft, you just don't have dogfights at that altitude. So as the AIM-9X is ascending from the 58,000 feet launch point up to the target somewhere between 60 and 65,000 feet, that's the most detail we've gotten on where the target actually was, it may have to maneuver, do some terminal maneuvers, and the endgame.

Now the balloon is not evading and is not running away, so it's still a pretty easy target. But would it have enough authority in its control surfaces up there in that very thin air to actually hit that target? Obviously it did, and they probably weren't worried too much about it at that point, but I bet that they were probably doing some pretty hardcore analysis in that three or four-day period between when they started looking at and got the authorization to shoot it down and when they actually shoot it down. Because I think if they missed that shot, just how bad that would've looked in front of the entire world with video cameras clearly showing the first shot missing or the second shot missing, and maybe getting it on the third one. But they got it on the first one, and everyone thinks that that's a really easy shot to take because it's a balloon and how hard could that be? But I think it was actually pretty hard and I was pretty impressed by how they pulled it off and did it on the first shot.

Brian Everstine:

There was one thing I wanted to touch on, and I would love to hear everyone's input on this. In the briefing a couple days ago, General VanHerck said that they weren't aware of the prior incursions by balloons. There was three under the Trump administration, one under the Biden administration. But in this case it was spotted as it approached the Alaska Air Defense Identification Zone on January 28th. They watched it drift over to Canada and it pretty much had eyes on it pretty much the whole time. And what I thought was interesting about that is, the Pentagon has its Unidentified Aerial Phenomena task force, and their report released a couple months ago said that there had been 163 balloon sightings. And there was an awareness gap as General VanHerck said, but I think that as this UAP program played out, they were able to take a lot of steps to increase their awareness in an envelope that isn't typically watched. And I'd love to hear everyone's input on how this can change what the Pentagon needs to do for air defenses.

Steve Trimble:

But when you talk about that UAP task force and the 160 or so balloons that they found, most of those are probably just weather balloons. Just every day there's hundreds if not over 1,000 weather balloons going up in different parts of the world. And those can be seen by pilots and by people on the ground in some cases. And that's actually one of the ingenious methods here by the Chinese. It's the perfect crime, you're not expecting a balloon to come across from China and cross your territory. You're just not looking for that because why would you do it in an age with satellites and cyber attacks and all that kind of stuff? Why? What is the balloon going to help you with? But it can hide in plain sight. I mean, it can melt into this expectation that there's weather balloons going up all the time that we don't really pay attention to because who cares?

So, that might have been part of this and maybe some of them are part of that UAP task force. NORAD also had Project Pathfinder where they went back for other reasons and analyzed all their radar data, and used machine learning and AI algorithms to refine how they can tell the difference on secondary and primary, well, and primary radars between aircraft and birds so that they don't have some of the mistakes that they've made in previous years with that. That might have filtered into this as well. Once they had the characteristics of this new balloon and were able to analyze it very specifically, they could probably go back through their radar data and identify other cases very specifically.

Graham Warwick:

Yeah, actually most radars have got speed gates on them. They actually have a range of speeds that they ignore in order to manage clutter. So, it's quite possible that a lot of these radars just don't see, but then don't track anything below a certain speed. And these things are going in essence at the same speed as the air around them, so maybe just... But I do think that what this flags up is, when Loon was doing its testing, some of its balloons went right the way around the world, but it did all of its testing in the Southern Hemisphere, where, by and large, a lot of the time it was not flying over land or if it was, was not flying over the land of the paranoid.

Going forward, particularly as we see these companies wanting to use these balloons for telecoms, for earth imaging... And I'm sure the Chinese are doing exactly the same thing, they've got people looking at how you use balloons to provide cell phone coverage... The whole idea of balloon was to provide cell phone coverage in disadvantaged parts of the world where there was no tower infrastructure on the ground. That's a large part of China. And some of those balloons will not behave themselves. Some of those balloons will go off course. So we do face going forward, just as technology advances, we face the risk that more and more balloons of nefarious and non-nefarious intent will start to go off course.

So, I do think that there is a need out of this to create a surveillance capability, a tracking capability and a protocol. I mean, if you are a commercial balloon operator and your balloon goes AWOL and you can't communicate with it to tell it to come down and it goes off, there has to be a red telephone for balloons. Because otherwise we'll have repeats of this event triggered... And they won't be weather balloons. The fact is we already have weather balloons and they happen all the time. These are going to be much larger balloons with heavier payloads. So, there will be a need to have some way of saying that there's a balloon on its way, but it's not of military intent, it is a thing, and we probably need a way to get these things out of the upper atmosphere if they're going to cause a problem. These are all things that are just, we probably weren't really thinking seriously about until something like this happens, and we have to think about them.

Joe Anselmo:

Well let's get into that because Brian raised a point that there were previous incursions by Chinese balloons, the military is now saying, over Florida and Texas, and they were undetected. When critics were calling this a Sputnik moment for the U.S., I scoffed, but is this a Mathias Rust moment? Mathias Rust was the German teenager who flew a Cessna 172 into the Soviet Union and landed it in Red Square, undetected. Is this that kind of moment, a wake up call for the U.S., Brian, or is that overstating it?

Brian Everstine:

I think it might be a little overstating it, but maybe the previous incursions that we weren't aware about might have been, but now we've seen the capability to be able to track it so early. The missile fields it flew over, you can see them on Google Maps. It's not really that big of a deal for an expanded capability that China has. It might be a wake-up call for the American public. I'm wondering why this had so much constant TV coverage when the disclosure of the China's FOBS (Fractional Orbital Bombardment System) test couple years back didn't have this much of a public reaction. But I don't know, Steve, Graham, any thoughts?

Steve Trimble:

Yeah, actually I do. Just on that point, I mean, when Mathias Rust landed in Red Square in the late 1980s, I believe, it was a very tense moment in the Cold War, and the Soviets had extensive air defense systems that, in the public mind anyway, were supposed to be this impregnable barrier to any type of penetration flight by anything, much less a Cessna 172, which is what Rust was flying. In the United States, we just don guard our airspace in the same way. It's a bit less than that, and we have satellites overflying us all the time as well. I do think it does make us understand that we do need to figure out where these balloons are coming from, if China is using them for some reason in this extended multi-year intelligence gathering operation. But in terms of actual impact to the public perception of our defensive capabilities and surveillance capabilities, I don't know if it would have the same impact as what Rust did in Moscow. But it's a fun comparison to make.

Joe Anselmo:

Well guys, we're just about out of time, but wanted to quickly go back to what are the U.S. Army's plans for the future?

Steve Trimble:

So the U.S. military has been looking at near space for years and years. They've tried a bunch of different projects. A lot of them have not worked out very well, like the high altitude, long endurance demonstrator that DARPA had that unfortunately crashed in Pennsylvania on its first attempt, things like that. But they're definitely trying to get things going, again. There's a program called HEIOS that's in the U.S. Army, this would be the stratospheric layer of what the Army's calling their multi-domain sensing system. Right now, that program is really focused on the medium altitude layer. So, they're trying to buy a new, it's a program called HADES, and they're trying to essentially get a Global 6000 or G550 type aircraft and load it up with some SIGINT and COMINT, maybe even a synthetic aperture radar and use that as a Guardrail replacement.

And so that's going forward, and right after that is when they want to get to and deal with this stratospheric layer. And they're looking at a lot of different things, including high altitude balloons as well as airships, as well as solar power gliders like the kinetic zephyr. But I think they're looking at going much higher than what the Chinese balloon could do, mainly so that it couldn't get shot down by their equivalent, I guess, a J-20 with a PL-10 missile or something like that. But they're struggling to understand what they can actually do, because when they go much higher than 60 to 65,000 feet, say 75,000 to 80,000, the SWAP, the size, weight and power capacity of what you can carry up there for long periods goes way, way down. And so they've looked at loads or power capacities in the single, well, in the tens of watts to maybe single kilowatts is what they're looking at. That doesn't give you a whole lot of capability, but they are very interested in getting into that region, that near space region, as they've been calling it.

Joe Anselmo:

And Graham, to wrap things up, you and I were talking about this whole thing. We've been talking about it all week, but there are really parallels to 1960 when the U.S. didn't yet have spy satellites. We were overflying the Soviet Union with U-2s, high altitude U-2s in the late '50s and into 1960, and the Russians shot one down. Just like this incident interrupted a summit between our U.S. Secretary of State and the President of China, it's scuttled a summit in Paris between President Eisenhower and Nikita Khrushchev, the Soviet leader. Is all the outrage over this balloon overblown? I mean, is this just the normal cat and mouse of espionage that's been going on forever?

Graham Warwick:

Oh wow. Given the questionable value of the intelligence that such a balloon over flight, if intentional, you have to think that the political fallout was part of the planning process, the timing, the whatever. I don't know. It just seems that the potential value of the data recovered seems to be outweighed by the political consequences of being found doing it. So, I don't know.

Joe Anselmo:

Steve, I'm already way over on this podcast. I know you want to have a final word on this. So have the final word

Steve Trimble:

You brought up 1960, the shoot-down of Francis Gary Powers. He was in the U-2, already the CIA knew that they needed to replace the U-2 with what became the A-12, which the Air Force version was the SR-71 that a lot more people know about. And that was the idea of, well we got to fly above it, we got to fly faster than it, Mach 3, 85 to 90,000 feet, that's where we're going to go. But there was an alternative proposal that they were looking at, the CIA and the Navy were looking at, that was to use a high altitude balloon. And they decided not to do that and go with the SR-71. Given the fact that we've had three of these balloons or cross our airspace, and this is the first one that we actually noticed, maybe they had the right idea with the balloon back in the 1950s. They did use smaller balloons at lower altitudes all the time back then as well before satellites became available, but they were also looking at this huge high altitude balloon as an alternative to the A-12 and rejected it, but then never used the A-12 for those types of overflights because it could be tracked. Anyway, so it's just a funny thing that I've been thinking about since this whole thing started,

Graham Warwick:

And I have a similar thought which is that the U.S. has tended to always try to over-complicate this. As I say, they looked at balloons, but what they've actually spent most of their time developing is actual airships. I mean large controllable airships. They want the ability to persist, and control, and loiter, and we've never been able to get it to work. Meanwhile, the Chinese appear to taken the idea of a basic balloon and made it work.

Joe Anselmo:

I found it ironic, Steve was talking about the U-2 and the U.S. was using a U-2 to actually follow this balloon as it traversed the United States. The U-2's still around, still being used.

So, guys, great conversation. Thank you for all your insights. Fascinating. That is a wrap for this week's Check 6 Podcast. A special thanks to our producer in London, Guy Ferneyhough.

A quick reminder that Check 6 is not Aviation Week's only podcast. Regular listeners will be familiar with Sean Broderick, Guy Norris and Lee Ann Shay. And this week they gathered at Aviation Week's Aero-Engines Americas conference in Dallas to record a special episode of our MRO Podcast about commercial engine supply chain problems. Also this week, check out our latest episode of the Air Transport Window Seat podcast hosted by Karen Walker, which focuses on new DOT rules into clamping down on the ancillary fees charged by airlines. I know we've all suffered from that. You can find both these episodes where you found this one.

Have a great week, and thank you for your time.

Joe Anselmo

Joe Anselmo has been Editorial Director of the Aviation Week Network and Editor-in-Chief of Aviation Week & Space Technology since 2013. Based in Washington, D.C., he directs a team of more than two dozen aerospace journalists across the U.S., Europe and Asia-Pacific.

Steve Trimble

Steve covers military aviation, missiles and space for the Aviation Week Network, based in Washington DC.

Graham Warwick

Graham leads Aviation Week's coverage of technology, focusing on engineering and technology across the aerospace industry, with a special focus on identifying technologies of strategic importance to aviation, aerospace and defense.

Brian Everstine

Brian Everstine is the Pentagon Editor for Aviation Week, based in Washington, D.C. Before joining Aviation Week in August 2021, he covered the Pentagon for Air Force Magazine. Brian began covering defense aviation in 2011 as a reporter for Military Times.