The massive propellers were too much for the matting that covers the helipad though which was sent flying when the USAF CV-22 Osprey took off.
Taken on Apr. 21, 2021 the video in this post features US Air Force (USAF) Boeing/Bell CV-22B Osprey 10-0053 (assigned to the 352nd SOW, 7th SOS at RAF Mildenhall) landing on Addenbrooke’s Hospital Helipad, in Cambridge, for medical-transfer training operations.
As noted by Alert5, the downwash during takeoff blew away the rubber matting of the hospital’s helicopter landing pad.
The CV-22 Osprey is a tiltrotor aircraft that combines the vertical takeoff, hover and vertical landing qualities of a helicopter with the long-range, fuel efficiency and speed characteristics of a turboprop aircraft. The mission of the CV-22 is to conduct long-range infiltration, exfiltration and resupply missions for special operations forces.

Clearly the massive propellers were too much for the matting that covers the helipad though which was sent flying when the Osprey took off.
The CV-22 is the Special Operation Forces variant of the US Marine Corps MV-22 Osprey. The first two test aircraft were delivered to Edwards Air Force Base, California in September 2000. The 58th Special Operations Wing at Kirtland AFB, New Mexico began CV-22 aircrew training with the first two production aircraft in August 2006.
The first operational CV-22 was delivered to Air Force Special Operations Command in January 2007. Initial operational capability was achieved in 2009. A total of 54 CV-22 aircraft are scheduled to be delivered by the end of 2021.
Video credit: Trailspotter