ilmapohjaiseen
Ilmapohjaiseen is a Finnish noun form that appears as the illative case of the compound ilmapohja. The word ilmapohja itself combines ilma (air) and pohja (base) and can refer to an air base or airfield infrastructure in aviation or military contexts. The illative form ilmapohjaiseen signals motion toward or into that base and is found mainly in historical texts, regional dialects, or specialized writings. In Modern Standard Finnish, the more common illative for ilmapohja would be ilmapohjaan; ilmapohjaiseen is less frequent and may reflect variation in spelling, regional usage, or stylistic choice.
Etymology and formation: ilmapohja is a compound noun formed from ilma and pohja, and ilmapohjaiseen is derived
See also: Finnish illative case, ilmapohja, air base, aviation terminology.
References: Finnish language references on noun inflection and aviation terminology, such as grammar resources from Kotus