This photo provided by South Korea Defence Ministry, shows balloons with trash presumably sent by North Korea, in South Chungcheong Province, South Korea. File
| Photo Credit: AP

North Korea’s trash balloon campaign, missile launches and the emergence of GPS “spoofing” have increased risks in South Korean airspace, aviation experts say, complicating airline operations as tensions rise between the rival nations.

In late May, North Korea began floating thousands of balloons with bags of trash, including human excrement, suspended under them into South Korea, in what analysts say is a form of psychological warfare.

Hundreds of balloons landed in the South during seven waves between May 29 and June 27, including one on a runway at Incheon airport, forcing a three-hour suspension of takeoffs and landings at its biggest international gateway.

When the balloons first appeared, aviation navigation interference from North Korea also spiked, including what appears to be the first bout of so-called “spoofing” affecting commercial aircraft in the South.

“Airspace safety is gradually deteriorating,” OPSGROUP, a membership-based organisation that shares flight risk information,” said in a June bulletin. “There are no official airspace warnings for South Korea, but the risk situation seems to be getting worse.”

South Korea’s Transport Ministry said its military, air traffic control authorities and airlines maintain a 24-hour surveillance and communication system.

“The South Korean military detects these balloons using surveillance assets… day and night,” a military spokesperson said, without giving further details.

North Korea, which also launched trash balloons in 2016, says they were retaliation for propaganda campaigns by North Korean defectors and activists in the South who send items via balloon.

Balloons have made flying in the area “quite complicated”

The balloon flights have several times shut down operations at Incheon, the world’s fifth-busiest international airport and an important cargo hub, about 40 km (25 miles) from North Korea.

“The balloons have made flying in the area quite complicated”, said Yun Chan Hwang, general manager of network operations for Korean Air Lines, which has adapted procedures to deal with the new hazard.

“If northerly winds are expected, the airline adds fuel to flight plans so aircraft can stay aloft longer or divert to alternative airports,” Mr. Yun said.

Disruption caused by the balloon campaign is being exacerbated by increased signs of interference to the Global Positioning System (GPS), a network of satellites and receivers used for navigation.

Militaries and other actors can broadcast signals that trick a GPS system into thinking it is somewhere it is not.

“This could lead pilots to drift off course, with the risk of straying into North Korean airspace,” said Kari Bingen, the aerospace security project director at the Washington-based Centre for Strategic and International Studies.

“Between May 29 and June 2 about 500 planes and hundreds of ships experienced GPS problems,” South Korea’s government said. It complained to U.N. aviation body ICAO, which warned North Korea to stop.

GPS spoofing appears new

“GPS interruptions in the South from North Korea have occurred for more than a decade, but spoofing appears new,” said SkAI, a Swiss company that runs a live disruption map.

“SkAI detected spoofing in South Korean airspace between May 29 and June 2 that affected dozens of planes,” co-founder Benoit Figuet said. “Some of the impacted airplanes were flying quite low in altitude. We even have seen airplanes being spoofed while being on the ground,” Benoit said.

Notifications to pilots issued by South Korea in May and June warned planes flying around Incheon and Seoul to “exercise extreme caution when using GPS”.

“No major aviation accident has been linked to GPS spoofing globally, but a business jet flying from Europe to Dubai nearly entered Iranian airspace without clearance in September 2023,” OPSGROUP said.

North Korea said last year it would shoot down anything it deemed a reconnaissance flight entering its airspace.

Most airlines avoid North Korean airspace. The U.S. Federal Aviation Administration bans overflights of North Korea for reasons including unannounced ballistic missile tests, air defence capabilities and potential electronic warfare.

“South Korea’s airspace is at constant risk of instability caused by some kind of political crisis,” OPSGROUP said. “Things have potential to change quickly, and without warning.”

Kim Yo Jong. File
| Photo Credit: AP

The sister of North Korean leader Kim Jong Un called South Korea’s recent front-line live-fire drills “suicidal hysteria” as she threatened unspecified military steps on July 8 if further provoked.

The warning by Kim Yo Jong came after South Korea resumed firing exercises near its tense land and sea borders with North Korea in the past two weeks. The exercises were the first of their kind since South Korea suspended a 2018 agreement with the North aimed at easing front-line military tensions in June.

“The question is why the enemy kicked off such war drills near the border, suicidal hysteria, for which they will have to sustain terrible disaster,” Kim Yo Jong said in a statement carried by state media.

She accused South Korea’s conservative government of deliberately escalating tensions as a way to escape a domestic political crisis. She said the riskiness of the South Korean drills is clear to everyone as they happened amid “a touch-and-go situation” established after the U.S., South Korea and Japan recently held a new trilateral military exercise that North Korea views as a security threat.

“In case it is judged according to our criteria that they violated the sovereignty of (North Korea) and committed an act tantamount to a declaration of war, our armed forces will immediately carry out its mission and duty assigned by the (North Korean) constitution,” she said, without elaborating.

Later on Monday, Koo Byoungsam, a spokesperson at South Korea’s Unification Ministry, described Kim’s statement as an attempt to trigger an internal divide in South Korea, saying that North Korea must first look at its own human rights violations and the international isolation caused by its nuclear programme.

South Korea’s Defence Ministry separately said it will continue its live-fire drills as scheduled but didn’t say when and where new exercises are planned.

North Korea has been engaged in a provocative run of weapons tests since 2022. But its two recent tests — one on a missile with “a super-large warhead” and the other on a multiwarhead missile — drew widespread skepticism from South Korean officials and experts who said North Korea likely fabricated successful launches to cover up failed tests.

In early June, South Korea fully suspend the 2018 inter-Korean military pact after North Korea flew balloons carrying manure, cigarette butts and wastepaper across the border to protest South Korean activists scattering political leaflets in the North via their own balloons.

The military agreement — reached during a short-lived era of reconciliation between the Koreas — required the two countries to cease all hostile acts at border areas, such as live-firing drills, aerial surveillance and psychological warfare. The deal had already been in the danger of collapse, with both Koreas taking steps in breach of it amid animosities over North Korea’s spy satellite launch last November.