Station Generators Questions

Q. When the electric goes off on an Raf Station how long does it last before it runs out of fuel ?

I wondered this because if that did happen the airfield would then be useless.

Q. Does the generator provide electric for the whole of the Tech side and the airfield or just the Tech Side ?

Regards,

HawkEye001

AVIA 13/451 states:

Airfield Electrical supplies are split into 3 groups: Permanent, Last Minute, and General.

Permanent included Ops Block, W/T installations, Central Boiler House, SSQ, SHQ, PBX, Runway Lighting, Bulk Fuel Installations, Watch Office, some Hangar supplies.

Last Minute was Officers' Mess and Qtrs, Officers Cook House, Sgts' Mess, Dining Room, further Hangar supplies.

The Last Minute and General Supplies were controlled from the Ops Block which could switch them off when required.

This system was first installed at Kenley with a 35kW generator.

Graham

Most airfields, including those I've worked on myself, depending on operational requirements (and depending on how well adhered to JSP554) have 415V generators for the B Centres which will feed airfield lighting and ILS and another for the Tower, A Centre, radar etc.

Again there are generators for ops, guard room, medical centres, the 'essentials' ect. How long they last often depends on sizes, but can run for most of the day, if not more going by the general size of generator and tank installed. If need be, POL would do refuelling runs of the tanks as the generator is running.

Some, but not many have an 11KV generator on the HV ring, with load shedding contactors to take non essential buildings off the load.

I assume that Carnaby is referring to WW2 airfield installations whereas Ant1981 is referring to contemporary airfields?

PETERTHEEATER wrote:

I assume that Carnaby is referring to WW2 airfield installations whereas Ant1981 is referring to contemporary airfields?

Not quite sure what one would call a contemporary airfield. But I'm talking about RAF airfields as of today.

Interesting debate. I well remember the monthly Stand-by generator tests that had to be done. I suppose stations varied but it always seemed to be on a Tuesday where I was. At the appointed time, usually about 9.00 am the station would switch to stand-by power. Operations would continue as would work in most of the hangars, but often other locations had to shut down due to lack of electricity. It always seemed that the Airmens' Mess kitchens would continue normally and I well remember during prolonged loss of external supplies the Officers and SNCOs having to go to the cookhouse to get food because their own Mess kitchens were closed. It was also surprising just what buildings lost their power and those which did not. I seem to remember that at Honington the Barbers Shop retained its electricity for some reason!

I asked the MPBW/DOE/PSA people why the generators had to be run, and why for so long - usually three or four hours. He said this was to make sure that there were no hot-soak problems with the switching and other systems but also to ensure that the engines were given a good thrashing. If they were run for only a few minutes at a time there was a risk of glazing the bores and causing premature failure of the engines. This was also the reason that after generators were switched off after a power failure, they would continue to run for some time after normal power was restored.

With the advent of the hardened era, a lot more generators of lower capacity were installed. Often individual buildings would have their own generator, eg the Pilot Briefing Facility etc. These were all equipped with self-starters and would spring into life the instant the incoming supply ran down. You had to keep your fingers out of the moving parts just in case they sprang into life without warning.

I notice that mentions a book called JSP 554. What does that describe? It it the I-Spy book of airfield electrical installations?

JCB wrote:

... and would spring into life the instant the incoming supply ran down.

ISTR the guy at Manchester Airport stated the generators for the runway lighting ran continuously. A drop in light for even a few seconds was not an option.

Graham

Our local Wessex Water had standby generators to take over from a mains power supply failure. That’s good thinking Batman, the only trouble was that their starter motors used mains to start. It took several lorries and sets of jump leads to get them going. That was a few years ago, with cut backs and hard times I wonder if they have learnt their lessons???