Gripen development

1
Gripen development
staffan.bogg_at_saab.sepresented at Meeting No.
96SAE Aerospace Control and Guidance System
CommitteeHilton Head, SCOctober 19-21 2005
2
Wake vortex

• Problem- AoA vanes might sense reduction in
  AoA/Nz initially at vortex passage- Elevons put
  in worse positions (compared to a/c without
  active FCS)
• Wake vortex transient reduction functionality-
  Implemented in OFP R146- Detection filter based
  on current AoA-information- Instant switching to
  complementary filtered AoA (instead of AoA based
  primarily on vanes position) at wake vortex
  detection- Ordinary AoA monitoring (CBIT)
  bypassed
• Flight Test- FQ Level 1 previously proved with
  filtered AoA- All vortex passages detected and
  FCS reconfigured to filtered AoA as designed-
  Flight tests to verify models rather than
  characteristics- Detection filter behaviour at
  low level flight (less than 150 ft) with
  turbulence to be explored

3
New functionality

• Improved Maneuver Load Limiting function- New
  export external stores- Heavier a/c and more aft
  c.g.- Basic design stores combinations, care
  free characteristics for all derivatives
  (nominal weapon release)
• Coupled Control functionality- Automatic
  navigation- Automatic/optimized climb
• Enhanced ALT mode- All attitudes (previoulsy
  limited to pitch angles of /- 60 deg)-
  Increased authority (roll rate/nz) at unnormal
  attitudes- Pilot Activated Fly Up