ADAPTATION OF MICROPHYSICAL AND CHEMICAL INSTRUMENTATION TO THE AIRBORNE MEASURING PLATFORM ILJUSHIN-IL-18-CYCLONE AND FLIGHT REGIME PLANNING DURING THE ARCTIC-HAZE-INVESTIGATION 1993-95

In 1993 the joint Russian-German Research Project 'Arctic Haze' starte d (see the Introduction and editorial note of this issue, by Jaenicke, Khattatov, Jaeschke and Leiterer). Besides CAO, four German groups we re involved. To the present three airborne measuring campaigns have be en performed. In total 251 h of flight within altitudes up to 8.7 km w ere flown in the western and eastern part of the arctic leading to a c omprehensive set of data of the northern arctic hemisphere. The measur ements were conducted aboard the Russian research aircraft Il-18 'Cycl one' which was used by CAO in numerous scientific projects mainly in t he former USSR. This 4 engined turboprop aircraft is well equipped wit h sensitive thermodynamical, optical and radiometric instrumentation. In consideration of the estimated aspects of 'Arctic Haze' additional microphysical, optical, and chemical instrumentation was adapted to th e research aircraft. For co-ordinated measurements a detailed flight r egime was planned taking into account the special requirements of the groups involved in the project. Main parts of the measurements were pe rformed in box flights designed to get representative information of t he investigated area. This allows the comparison of results gained in individual boxes at different locations or at different seasons. This contribution describes the basic equipment of the Russian research air craft IL-18 as well as the adaptation of the special instrumentation f or the 'Arctic Haze' investigations. (C) 1997 Elsevier Science B.V.