| Significance | Code | Meaning |
|---|
| FIR | EGTT | London FIR | | | / | | | Qualifiers | Q | | | | NB | Nondirectional radio beacon | | | AS | unserviceable | | | / | | | Traffic | I | IFR traffic affected | | | V | VFR traffic affected | | | / | | | Purpose | B | For inclusion in Preflight Infomation Bulletins | | | O | Operationally significant for IFR flights | | | / | | | Scope | A | Aerodrome information | | | / | | | From flight level | 000 | Surface | | | / | | | Up to flight level | 999 | Unlimited | | | / | | | Centre Latitude | 5131N | 51° 31' North' | | Centre Longitude | 00041W | 0° 41' West | | Radius of area affected | 005 | 5 nautical miles |
| | NON-DIRECTIONAL BEACON BUR / BURNHAM 421KHZ UNSERVICEABLE |
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