USE OF DATA FROM ON-BOARD DATA RECORDERS FOR ACCEPTANCE TESTS OF AVIONIC DRIVING UNITS

The paper explains how information stored in on-board recorders of flight parameters can be used for acceptance tests, also referred to as qualification tests. The disclosed example refers to the An-28 ‘Bryza ’ aircraft where an old airscrew was substituted with the new generation Hartzell airscrew of the HC-B5 MP-3D type. The airscrew is an integral part of the driving system for the airscrew propelled aircraft that is provided with the TWD-10B engine. After revamping of the airscrew, the aircraft was named as TWD-10B/PZL-10S. The follow-up investigations were carried out with the aim to find out how much the airscrew substitution affected the alteration of key performance characteristics achieved by the driving unit of the aircraft. The investigations comprised both ground and in-flight tests and have led to determination of the essential characteristics for the engine operation as well as variations of the operational parameters in time. In some cases also so called phase portraits were found out for parameters of the engine operation so that to reflect dynamic properties of the engines. Such investigations are indispensable since the aircrafts are subject to operational limitations and technical conditions that must be mandatory fulfilled due to requirements of flight safety. The paper demonstrates that the data stored in on-board recorders of flight parameters can be really useful for execution of such acceptance (qualification) tests