The US Federal Aviation Administration has published Engineering Brief No. 105A, Vertiport Design, Supplemental Guidance to Advisory Circular 150/5390-2D, Heliport Design, a revision to the original EB 105 issued on September 21, 2022.
According to the FAA:
“Principal changes include adjustments to the infrastructure classification, landing area geometry, markings, the addition of a section on parking, and the creation of a downwash and outwash protection area:
“1. Infrastructure Classification: Transitioned this EB to be supplement guidance to advisory circular (AC) 150/5390-2D, Heliport Design. Vertiports are a type of heliport with distinct specific requirements similar to hospital or prior permission required (PPR) heliports. The heliport design AC was established for heliports serving helicopters with single, tandem (front and rear) or dual (side by side) rotors. EB 105A provides guidance for vertiports (a type of heliport) serving aircraft with three or more propulsors.
“2. Marking: Updated the vertiport marking to align with other classes of heliport infrastructure. Vertiports are distinguished with the addition of a “VTL” marking on the touchdown and liftoff area (TLOF). See paragraph 4.0.
“3. Geometry: Laid the foundation for updating the landing area geometry, creating a subset of the controlling dimension (D) related to just the propulsion devices. Where D is the diameter of the smallest circle enclosing of the entire VTOL aircraft projections, RD is the smallest circle enclosing just the propulsion units, which for some vertical takeoff and landing (VTOL) designs may be smaller than D. The geometry of the TLOF and final approach and takeoff area (FATO) are now related to the RD rather than D. The safety area has decreased in size. See paragraph 2.0.
“4. Parking: Created a new section on VTOL parking with larger parking positions that support air or hover taxiing to them rather than just ground taxiing. See paragraph 3.0. 5. Downwash and Outwash Caution Area: Added a downwash/outwash caution area (DCA). Refer to the Federal Aviation Administration (FAA) Technical Center research report DOT/FAA/TC-24/42, eVTOL Downwash and Outwash Surveys, on velocity findings for example distances for aircraft 7,000 lbs (3,175 kg) and less. See paragraph 2.5.
For more information
https://www.faa.gov/airports/engineering/engineering_briefs/eb_105a_vertiports