Safely carrying cargo and passengers on an aircraft is not an easy thing, weight distribution and load have to be correct to ensure the aircraft can take off safely and equally importantly get to its destination and land safely. Calculations are needed to ensure the aircraft is not overloaded, and this becomes especially important on large cargo aircraft such as the Hercules. To assist aircrew, the air force has long made use of manual computers that allow the information to be entered, and results read off by turning a dial and setting it to the correct figures, this calculator comes in a plastic cover, the original owner has written his name on the front:Taking the computer out of the case we can see that it consists of two white plastic discs that rotate over one another and allow the calculations to be made:The centre of the computer indicates the aircraft type it’s for, the Hercules, and its use, a trim computer:As can be seen below this is the details indicating that it was designed by the Operational Research Branch for the Royal Air Force. A further table is printed on the rear, offering further assistance to the user:A series of numbers are printed around the rims of the two discs, with a clear slider that can also rotate:I must confess I have little aeronautical knowledge so the exact purpose of the computer and how to use it are beyond me. The Hercules has been the workhorse of the RAF for many decades, the following information form the RAF’s own website offers some interesting information on the current use of the venerable aircraft:

The C-130 Hercules tactical transport aircraft is the workhorse of the RAF’s Air Transport (AT) fleet and is based at RAF Brize Norton, in Oxfordshire , where it is operated by Nos 24, 30 and 47 Squadrons. The fleet comprises a mixture of C-130K C1/C3 and C-130J C4/C5 aircraft.

The C1 and C3 aircraft are used primarily to carry troops, passengers or freight and are capable of carrying up to 128 passengers, or 20 tonnes of palletised freight or vehicles, for up to 2000nmls. The freight bay can accommodate a range of wheeled or tracked vehicles, or up to seven pallets of general freight. In the aeromedical evacuation role either 64 or 82 stretchers can be carried, depending on the mark of aircraft and the stretcher configuration. The maximum unrefuelled ferry range is 3500nmls, which can be extended to over 4000nmls by air-to-air refuelling. The other main role of the C-130 is Transport Support (TS), which is the airborne delivery of personnel or stores by airdrop. In this role the aircraft supports airborne operations conducted by 16 Air Assault Brigade by the aerial delivery of paratroops, stores and equipment. The aircraft is particularly valuable in its TS role as it can be operated from unprepared and semi-prepared surfaces by day or by night.

The majority of aircraft are fitted with defensive infrared countermeasure equipment, whilst some aircraft used for special tasks have an additional, enhanced defensive-aids suite comprising a Skyguardian radarwarning receiver, a chaff and flare countermeasure dispensing system and a missile approach warning system. The C3 is also equipped with station-keeping equipment, which enables the aircraft to maintain its airborne position in a large formation in thick cloud or bad weather where the other formation members cannot be seen. The aircraft are receiving an ongoing avionics, electrical and structural upgrade, which will enable them to remain the workhorse of the AT fleet into the next decade.