TOP SECRET The radius of action of the transport aircraft based on airfields not West of Berlin would limit the threat of airborne operations east of a line WEYMOUTH LIVERPOOL EDINBURGH. Conclusion 6. Without major movements of troops and aircraft, both of which we feel confident would come to our notice, the maximum force that could attack this country at short notice would be approximately half a Brigade. Recommendation 7. We recommend that the Chiefs of Staff approve this report and forward it to the Prime Minister for his information.