You should complete the Pre-application Statement of Intent (PDF) (PASI) form and submit it to the FAA once your business plan becomes viable. Provide enough information in Box 10 of the PASI for the FAA to assess size and scope of your proposed operation.
When the FDSO receives your signed PASI, they will review the form to ensure that there is sufficient information to further process the pre-application. The completed PASI will be submitted to the FAA Flight Standards District Office (FSDO).
When the PASI is acceptable, the FSDO manager will initiate the Certification Services Oversight Process (CSOP) found in FAA Order 8000.92, to determine the availability of resources to support the certification project. The CSOP assures that sufficient FAA resources are available to support you during the certification process.