L J
sorry, I thought you were a pilot. The AIP is the "Air Pilot" whuich is the bible for flying in the UK. The reference was to a section dealing with Heathrow (code EGLL).
The hold is based overhead the LAM beacon and is a racetrack turning 180 degrees away from the beacon, going straight for 1 minutes' flying time, then turning back towards the beacon and flying back (nominally) 1 minute until overhead, and then doing it all over again!
I haven't got a BNN chart in front of me, but I suspect the 222 degree line would be the track flown by an A/c following the radial from the BNN VOR. As DrKaos said, these procedures are designed to be flown by the pilot in the event of NO radar vectors from ATC (typically radar or radio failure). The radar vectors chosed by the ATCO would be similar to the non-radar pattern, but changed tactically to fit into the traffic sequence.
As to the symbol, it depends which chart you're looking at. Usually the NDB is circles of dots. A VOR is a hexagon and a VOR/DME is a hexagon in a box with a dot in the middle.
The NDB just sends out a signal in all directions and the needle in the cockpit points to it (hence Non Directional Beacon). The VOR sends out a pair of beams by which the equipment in the cockpit can detect it's displacement from any one of 360 tracks out (called radials). Dial up the radial you want and the needle says "fly left/right" until you're on it. Combined with DME (distance measuring equipment) you get what mathematicians call a polar coordinate...a point a known distance on a known bearing from a fixed origin.
I didn't realise I remembered so much of this crap
Tori