With the US shooting down a fourth unidentified object over US airspace on 11 Feb 2023, it has been an unprecedented week or so for NORAD and the homeland defence. Among the four objects that have been brought down is the well publicised Chinese balloon that was shot down by an F-22 using a single AIM-9X missile from an altitude of about 18,000 meters (58,000 feet) on 04 Feb 2023. The other three that have been brought down have not been “identified” with reports ranging from octagonal shape to unknown origin. This has led to some bizarre speculation as to their nature and origin. When asked by reporters if officials have ruled out extraterrestrial origin, Gen Van Herck, Chief of NORAD is quoted as saying “I haven’t ruled anything out at this point”.

While Pentagon officials have acknowledged that this sequence of events has no peacetime precedent, other United States officials have said that China’s surveillance balloon programme is not limited to the US and has also been used to spy on India ^[1]. The fact that another balloon has been seen over Latin America has lent further credence to the fact that a Chinese military unit in charge of outer space and cyber warfare was involved in the operation of these balloons and this activity has been going on for years. A senior U.S. State Department official has stated that the Chinese maker of the balloon has a "direct relationship" with the People's Liberation Army. The official said the large balloon, equipped with multiple antennas and solar panels, was capable of conducting signals intelligence collection operations.^[2] After initial hesitation, China admitted ownership of the "airship" but said it was a weather balloon that had been blown off course. Chinese foreign ministry said: "The airship is from China. It is a civilian airship used for research, mainly meteorological, purposes." In view of these developments it is pertinent to analyse the whole area of the near space and what it means to the future of surveillance in the military domain.

Near space can be described in simple terms as the area between commercial (or military) airspace and the low earth orbit. ICAO has published flight levels up to FL 510 or 51000 feet corresponding to an altitude of about 16 Km. Military aircraft like SR-71, Mig-25 and U-2 have flown regularly at 70000 feet (21Km). Russian pilot Alexandr Fedotov holds the world altitude record, set on August 31, 1977, when his MiG-25 (designated E-266M) reached 123,523 feet. Low Earth Orbit (LEO) altitudes start typically at 300 km from the earth’s surface. Hence near space can be roughly defined as the altitudes between 20 and 100 Km.

A lighter than air platform such as a balloon with limited steering capability (i.e. a dirigible) operating in near space is a much lower technology solution than a high flying air breathing platform or a satellite. Putting up such a platform in near-space is easier and much less expensive than launching a system into orbit. Therefore, near-space systems can provide responsive capabilities much sooner than orbital platforms. Military near-space vehicles can operate above the weather, be inherently stealthy, and fly above the range of nearly all threats. Near space has a stable weather conditions and is not affected by meteorological events. A typical near space balloon would operate between 65,000 and 95,000 feet and use gas venting and ballasting to control its altitude, in order that that its flight path can be optimized based on wind patterns in the atmosphere. Near space has an advantage in surveillance as vehicles in this airspace can cover a much wider area as compared to reconnaissance aircraft. In terms of distance, the vehicles would be 20 times closer to the Earth than low Earth orbit (LEO) satellites yet offering large coverage areas.

Such balloons would be operationally quite useful along large borders such as the Line of Actual Control (LAC) between India and China. As can be seen, they have some disadvantages too i.e. they can veer off course and can be shot down using high altitude fighter interceptors. As ground based Lasers become more powerful and proliferate, these disadvantages will be amplified. Despite these disadvantages they do pose challenges for air defence as radars have to scan at high elevation angles as well as adjust their speed gate filters in order to detect them and sophisticated, expensive missiles are required to shoot them down.

The other advantages that accrue from such systems are that these are persistent, cost effective, reasonably survivable (no SAM can reach such altitudes), and responsive. They can be designed to be expendable if needed. With advances in solar power and fuel cell technologies they can be self powered for long durations and relieve the burden on high value strategic assets that are currently used for surveillance. The current Ukraine war has shown us the ISR gap between western assisted Ukraine and Russia as well as how that gap has increased the cost for Russia in its “special military operation”. Complete battle space awareness will become a reality when data is successfully fused from old, current, and new technologies and pushed down to decision makers in the field.

Some of the current programmes that are developing Near Space Vehicles (NSVs) or carrying out conceptual studies for using capabilities of the near space are USA Sanswire Networks HAA (High Altitude Airship), NASA Stratosat, Helios; DARPA UAS (Unmanned Airship), Odysseus, Zephyr, Italian Polytechnic University HALE, and Germany HALE. Research has been particularly attractive because some sensors in space have started to reach the limits of their performance. For example NSVs could carry larger cameras with lenses of higher focal length and this combined with the lack of correction needed for ionospheric correction would lead to much sharper resolution. For Synthetic Aperture Radar (SAR) payloads also the resolution would be sharper than from space based platforms. These qualities when weighed along with the far greater persistence as compared to space based assets and manned aircraft makes this a very promising area. Lighter than Air (LTA) NSVs are also more cost effective than UAVs with estimates of a balloon based system like the Chinese object that was shot down on 04 Feb 2023 being about $ 15 million as against about 50 million for a Global Hawk type system.

Near space is not space, and most countries would recognize it as a part of a country’s sovereign airspace. A review of international law, international treaties, conventions, agreements and tradition, reveals that “there is no formal definition of where space begins.” While a specific altitude is not mentioned; however, those same conventions define the lower boundary of space as the lowest perigee sustainable by an orbiting space vehicle. Since NSVs are not orbiting spacecraft, by international law are in a country’s national airspace, regardless of altitude.

Aircraft and balloons traveling through near space are not new - the U-2 has been flying above 60,000 feet (ft) since the late 1950s followed by SR-71s. More recently, the RQ-4 Global Hawk has flown operational missions above 60,000 ft. Therefore operational missions in near space have to be flown with over flight rights or in conditions of air dominance. Much however is possible while remaining in own territory. China has shown its capabilities on LTA platforms in recent days. It is also extensively flying HALE UAVs regularly along the LAC especially in Eastern Ladakh. It has recognized the utility of this vertical region and has the first mover advantage. Chinese researchers, both armed services and servicemen have submitted more than 1,000 studies and reports on "near space," many of which concentrate on the improvement of "near space flight vehicles," according to reviews on CNKI, China's biggest online educational database. Since China is the centralis mores in the balloon saga and has done extensive research in the areas of LTA and NSV there is a threat posed to the LAC by such developments. It is therefore incumbent on India to study the near space region and exploit it in its national interest as well as track movements of such LTAs its adjacent airspace.

The missions that LTA NSVs can perform for the Indian military are surveillance and reconnaissance, communication, navigation, SIGINT and space support. The importance of ISR has been driven home by the occurrences in the Ukrainian war. There is a large asymmetry in the satellite capabilities of India and China leading to an “ISR gap” at the current deployment on the LAC. The near space region offers an opportunity to close the gap quickly with lower costs. In addition to military uses several civilian uses such as disaster monitoring, 5G, TV broadcast and disaster communications are possible. As the research into near space proliferates especially for LTA NSVs, a critical resource i.e. Helium would also need to be secured.

In conclusion, the shooting down of the Chinese balloon by the US has brought into focus the area of near space and the relevance of LTAs in that area. The episode has many lessons for India as China seems to have found a new way to exploit this region. It has also brought to the fore the lessons of ISR and the growing realization that any battle space of the future will need to include constellations of sensors in orbit, in near space, and in the air. As of today, the air and space platforms do not provide persistent ISR coverage all day, every day. Manned reconnaissance and surveillance platforms have the same low-density, high-demand challenge as the space based platforms. Unmanned platforms are beginning to fill the gaps but not quickly enough. Placing advanced platforms in near space lowers the sensors from the ultimate high ground of space. The sensors are closer and thus have better resolution. Near space is a promising vertical air space for national security considering the advantages of NSVs as compared to other platforms in terms of cost-effectiveness, payload handling, endurance, mobility, high resolution, and coverage.

Endnotes :

^[1]https://www.ndtv.com/india-news/chinese-spy-balloons-targeted-india-several-other-countries-report-3762998
^[2]https://english.kyodonews.net/news/2023/02/8ff341a71a97-breaking-news-chinese-military-unit-involved-in-balloon-operation-sources.html?phrase=sex%20offender&words=
^[3]MAJOR ANDREW J. KNOEDLER Using Near Space Vehicles in the Pursuit of Persistent C3ISR, JUN 2005

(The paper is the author’s individual scholastic articulation. The author certifies that the article/paper is original in content, unpublished and it has not been submitted for publication/web upload elsewhere, and that the facts and figures quoted are duly referenced, as needed, and are believed to be correct). (The paper does not necessarily represent the organisational stance... More >>