https://www.caa.co.uk/Our-work/Newsroom ... collapse-4
Engine health flights. The main way of maintaining engine health during COVID restrictions should be through winterisation or inhibition. Engine health flights are only permitted, where required by the engine manufacturer or equivalent LAA/BMAA procedures for Permit-to-Fly aircraft. Flights must follow those procedures and there must be a four-week gap between flights. Each flight must be no more than 30 minutes (or as recommended by the engine manufacturer in order to prevent internal engine corrosion). Aircraft should aim to remain within the airfield circuit. Unless safety of flight requirements dictate, the aircraft should not travel beyond a 10nm radius of its departure aerodrome and no dynamic manoeuvring activity should be flown. Each flight should be at the highest practical height to minimise to the noise impact on members of the public maintaining social distancing, and not below 1,000ft AGL except for take-off, approach and landing. If the engine manufacturer's instructions indicate that the engine only needs to be run at idle or at low power whilst on the ground and no other essential maintenance is required, then no flight may be performed.
Criteria for the conduct of these flights:
while the UK Government's social distancing policy is in place the owner or organisation operating the aircraft must maintain a log of all the aircraft movements. As a minimum, this must include the purpose of the flight, the aircraft registration, the pilot and their licence number, the flight's date, time and duration. This log is to be kept and if required provided immediately in electronic form to the CAA.
Only solo flights by fully qualified pilots are permitted. No other flights, including instructional sorties are allowed. Aircraft must not be rented-out or flown for financial gain.
Aircraft must have a valid airworthiness certificate (CofA, Permit or Permit Flight Release Certificate) before a maintenance, ferry or engine health flight can take place.
These provisions apply equally to UK-registered and non-UK registered GA aircraft operating in UK airspace.
Any requests for exceptions to these provisions are to be submitted to firstname.lastname@example.org a minimum of 10 days in advance of the requested date of the flight.
At all times, the measures outlined by the UK Government to reduce the risk of the spread of COVID-19, such as social distancing, personal hygiene and minimising travel remain applicable, and pilots and operators undertaking flights on the basis permitted here must observe these. Aerodrome operators must also ensure that such flights are coordinated so that social distancing measures are not compromised at their location.