What aircraft was involved and where did it happen?

The accident on 2019-08-06 involved a Tecnam P2008-JC / Cessna 152, registration SP-HSI / SP-KWW, at TMA Łódź, PL.

What was the probable cause of the accident?

The near-miss was caused by the Cessna 152 climbing to a new altitude without notifying air traffic control, combined with a failure by the Cessna crew to maintain adequate visual separation from the other aircraft.

Mid-air near-miss between two light aircraft in Łódź TMA

Two aircraft flying under VFR rules experienced a close encounter in the Łódź controlled airspace after both crews independently decided to climb without notifying air traffic control.

What happened

On August 6, 2019, at approximately 08:21 UTC, a Cessna 152, registration SP-KWW, departed Łódź Airport (EPLL) on a VFR flight. The crew was cleared to fly via point YANKEE toward point WHISKEY at an altitude of 1,80 and requested a direct route from YANKEE to WHISKEY, which was granted by the tower controller.

Simultaneously, a Tecnam P2008-JC, registration SP-HSI, was conducting a training flight in the Łódź CTR. At 08:29, the Tecnam crew reported their position near point HOTEL and received clearance to fly toward point GOLF at 2,000 ft. The controller informed the Tecnam crew of the climbing Cessna 152 at 1,800 ft. The Tecnam crew acknowledged the traffic information, stating they were looking for the other aircraft.

Shortly after, the controller informed the Cessna 152 crew of the Tecnam aircraft approaching point WHISKEY at 2,000 ft. The Cessna crew acknowledged the information, stating they were maintaining 1,800 ft.

At 08:36, radar displays showed the two aircraft positions overlapping near point WHISKEY. The Tecnam crew, flying at 2,020 ft, observed the Cessna 152 passing approximately 50 ft above them. Following the encounter, the Tecnam crew reported they had increased their altitude because the Cessna 152 appeared to be significantly higher than the previously reported 1,800 ft.

The investigation

The investigation established that the encounter occurred within Class D controlled airspace. While the controller provided traffic information to both crews, the investigation focused on the actions taken by the pilots following these transmissions. The controller conducted communications in English with the Tecnam crew and in Polish with the Cessna crew; however, the use of different languages was not found to have impacted the understanding of traffic information.

Findings

The primary cause of the incident was the unannounced increase in altitude by the Cessna 152.
The crew of the Cessna 152 failed to maintain proper visual lookout for other aircraft.
Both crews made independent decisions to climb to avoid or adjust to the other aircraft's position without notifying the tower controller, which is a requirement in controlled airspace.
The Tecnam crew increased their altitude after the near-miss had already occurred, while the Cessna crew had increased their altitude prior to the encounter.