6.1   RUNWAY

The problem:

• Runway operation frequency limits the number of slots

Possible constraints:

• Airports may limit number of slots per airline 
• Airports may introduce “flat” landing fees to discourage small aircraft 
• Airports may ban “small” aircraft (limit around 100 seats)

Conventional solutions:

• All aircraft to approach with same speed to maintain minimum distance
• Aircraft to use high speed turn-off’s as available

Advanced solutions:

• Smaller minimum distance between approaching aircraft
  • Improved flight control 
  • Improved ATC 
  • new vortex break up devices and detectors
• High speed turn-off’s closer to end of runway
  • lower approach speed
  • better touchdown precision
• Use secondary runway
  • lower approach speed for shorter landing distance
• UHCA
  • Less aircraft needed for more people

Problems arising from the OHCA:

• High runway loading
  • Bridges, tunnels underneath the runway
  • Runway on piers
• High vortex generation
  • Big distance between UHCA and smaller aircraft
• Aerodynamic and engine noise
• Wing span
  • Other aircraft may not move if UHCA moves
  • Other aircraft may not be close to runway
  • Clearance between taxiways/runways
  • Clearance between two runways

Solutions for a UHCA:

• Stabilise bridges
  • High weight cut off
• Only big aircraft are allowed to start behind UHCA
  • Separation of aircraft
• Folding wing
  • Tracking system on runway to allow closer distances to other objects
  • Wing tip collision warning system