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Civil Aviation Authority of Singapore
E-services

Application for obstacle clearance

Apply for clearance before conducting activities such as development of buildings, use of tall construction machineries such as cranes, or facilitating ship crossing.

Access SkySAFE (opens in new tab)

Development of buildings, use of tall construction machinery such as cranes and ship crossing can potentially affect safety of air navigation either due to the close proximity between the structure and an overflying aircraft, or the structure may cause an obstruction along the flight path.

As such, prior clearance needs to be sought from CAAS before interested parties carry out such activities.

Applicants can make an application via SkySAFE (opens in new tab) for the following obstruction control activities:

  • Erection of cranes and tall construction machineries

  • Ship crossing