Orb expertise needed.

That was very interesting and informative, thanks.

Thanks Ross.

What it says on the tin.

If you wanted to move an aircraft by air in wartime before you took off you applied to the Movement Liaison Section for a Movement Serial Indicator and to tell them your route with approximate timings. The MLS gave you next available serial from a letter/number sequence and recorded your details on a list which was sent to all filter rooms.

When the aircraft was picked up on RDF/Radar/Observer Corps and reported as unknown to filter room the duty Movement Liaison Officer looked up his list for who was authorised to be there and said either “friendly MSI – disregard” or “hostile – engage”.

Ross

Thanks Ross. Could you please explain that in layman’s terms.

Movement Serial Indicator issued by the Movement Liaison Section.

Used to classify RDF plots.

Ross

Bumping this one up again in the hope someone can answer my query.

Thanks, David