R.A.F. Aircraft - Damage Categories
Pre 1941
Cat.U Undamaged
Cat.M(u) Capable of being repaired on site by the operating unit
Cat.M(c) The repair is beyond unit capacity.
Cat.R(B) Repair on site is not possible; the aircraft must be dismantled and sent to a repair facility.
Cat.W Write-Off
1941 - 1952
Cat.U Aircraft Undamaged
Cat.A Aircraft can be repaired on site
Cat.Ac Repair is beyond the unit capacity, i.e. may be repaired on site by another unit or contractor
Cat.B Beyond repair on site, i.e. repairable at a Maintenance Unit or at a contractor's works
Cat.C Allocated to Instructional Airframe duties
Cat.E Aircraft is a write-off
Cat.E1 Aircraft is a write-off but is considered suitable for component recovery
Cat.E2 Aircraft is a write-off and suitable only for scrap
Cat.E3 Aircraft is burnt out
Cat.Em Aircraft is missing from an operational sortie (missing aircraft categorised "Em" after 28 days)
In addition to the above the cause of the damage is sometimes indicated by a prefix or suffix, thus;
FA Flying Accident
FB Operational Loss
GA Ground Accident
T Technical Cause
EA Enemy Action
Source:
http://www.k5083.mistral.co.uk/DAM_CAT.HTM
JAN