Downwash and Outwash

Helicopter downwash and outwash is a known problem that has caused fatal accidents and damage around landing sites. Some attempts have been made to inform users of downwash issues, such as this video produced by BP, with my assistance, in 2016 - 
https://www.youtube.com/watch?v=09bvuYRKwwc

A Coroner’s Report into the death of Mrs Jean Langan at Derriford Hospital, identified that she died after a landing helicopter’s downwash caused her to fall backwards and strike her head on the ground. 

The Coroner issued a REGULATION 28 REPORT TO PREVENT FUTURE DEATHS that identified concerns over the lack of a real time data base of Hospital Helicopter Landing sites to ensure the safe landing of helicopters. As the Department for Transport (DfT) identified in their response to the Regulation 28 Report, hospital landing sites are unlicensed and so they do not have to comply with the Guidance in CAP 1264. Ultimately, it is the helicopter operators using these sites that have to ensure they are safe to use. However, the hospitals (NHS), DfT and the CAA must all play a part, but I see some buck passing occurring. In the meantime larger SAR helicopters are unable to use many hospital sites, resulting in delays to treating casualties as they have to be landed at alternative sites and then moved by ground to the critical care they often require.

In April 2025 the CAA published CAP 3075-  
Protecting the Future: Trials and Simulation of Downwash and Outwash for Helicopters and Powered Lift Aircraft https://www.caa.co.uk/publication/download/24645

This follows on from CAP 2576 - 
Understanding the downwash/outwash characteristics of eVTOL aircraft https://www.caa.co.uk/publication/download/20721  

​Both of these CAPs are based on research support from Sophrodyne Aerospace - https://sophrodyne-aerospace.com/