The services do not set official guidelines on voluntary outflow (VO) rates. They assess the acceptable range of voluntary outflow in terms of the ability to provide sustainable manpower structures and, in particular, the maximum capacity of training pipelines that supply replacements for those who leave. Actual outflows are monitored against these assumption and constraints and action is taken to respond, for example, by the use of a Financial Retention Incentive.
Current voluntary outflow rates for pinch point trades are shown in the following table:
Pinch Point Trade VO Rate (percentage) Royal Navy (as at 1 July 2007) Able Bodied Seaman 6.5 Merlin Pilots 4.0 Merlin Observers 1.7 Merlin Aircrew 5.0 Leading Hand Warfare 4.4 Able Bodied Diver 2.4 Royal Marines Other Ranks 6.3 Leading Hand Air Engineering Technician 2.0 Petty Officer Mine Warfare 5.4 Able Bodied Warfare Specialist (Sensors Submariner) 4.3 Able Bodied Warfare Specialist (Tactical Submariner) 6.5 Strategic Weapons Systems Junior Ranks 3.3 Nuclear Watchkeeper 2.7 Army(as at 12 February 2007) Royal Electrical and Mechanical Engineers Vehicle Mechanic 1 5.8 Royal Electrical and Mechanical Engineers Recovery Mechanic 5.7 Royal Electrical and Mechanical Engineers Armourer 5.1 Royal Engineers Clerk of Works 1.8 Army Medical Service—General Surgeon 0.0 Royal Engineers Mechanical Engineer Fitter 8.2 Royal Logistics Corps Ammunition Technician 4.2 Royal Logistic Corps—Postal and Courier Operator 5.9 Royal Logistics Corps Movement Controller 2.9 Queen Alexandra's Royal Army Nursing Corps—Radiographer 10.4 Royal Engineers Military Engineer Geographic 5.8 Intelligence Operational Military Intelligence 5.0 Royal Engineers Explosive Ordnance Disposal 2 3.8 Royal SIGNALS Information Systems Engineer 3.7 Royal Engineers Command, Control and Communications Systems 9.5 Army Medical Service—General Medical Practitioner 5.8 Royal Logistics Corps Chef 2.5 Queen Alexandra's Royal Army Nursing Corps—Operation Department Practitioner 3.6 Royal Logistics Corps Petroleum Operator 6.3 Army Medical Service—General Duties Nurse Soldier 10.3 Royal Artillery—Operator Unmanned Aerial Vehicle 10.9 Army Medical Service—Nurse Officer 8.5 Army Medical Service—A&E Nurse Officer 0.0 Army Medical Service—Anaesthetist 0.0 Army Medical Service—Radiologist 0.0 Army Medical Service—Orthopaedic Surgeon 0.0 Army Medical Service—Intensive Therapy Unit Nurse Officer 0.0 Royal Air Force (as at 1 May 2007) Medical 2.3 Operational Support (Intelligence) 2.1 Operational Support (RAF Regiment) 2.7 Operational Support (Provost/Security) 5.1 Princess Mary's RAF Nursing Service 2.3 Weapons Support (Air Load Master) 0.6 Weapons Support (Linguist) 0.0 Air Traffic Control 2.3 Flight Operations Manager/Flight Operations Assistant—Sergeant 4.8 Firefighter 10.6 Gunner 5.3 Movements Operations/Controller 3.4 Motor Transport Technician 2.5 RAF Police 4.2 Staff Nurse (RON) A&E 6.4