Aircraft flight control

  • Christensen, Erik Lintz (Project Manager)
  • Madsen, Søren Nørvang (Project Participant)
  • Woelders, Kim (Project Participant)

    Project Details

    Description

    The performance of a synthetic aperture radar is dependent on the aircraft moving smoothly along a great circle with high accuracy although some means exist for corrections provided the actual flight path is known with sufficiently high accuracy. The requirements on the actual flight path is much more rigorous when the SAR is to be used for repeat track interferometry (RTI) and the instrumentation of the Danish Air Force Gulfstream G-3 does not permit sufficiently accurate control of the aircraft.
    An automatic control system was developed during 1995 capable of keeping the aircraft within a few meters from the planned track as measured by the GPS system. The system controls the aircraft by emulating the instrument landing system (ILS) which is thereby used at 41,000 feet altitude at normal cruising speed. Fast fluctuations with around 1 m peak deviation were observed and some effort has been put into identifying the reason for those. The source is the aircraft flight control computer or the autopilot which operate with increased loop gain in the ILS mode. Correction of the deviation is problematic since the primary safety of the aircraft depends on these instruments. (Related projects - see: www.dcrs.dtu.dk).
    StatusFinished
    Effective start/end date01/01/199531/12/1997