A source document for info, para 9 emphasises BOAC's point.
UNITED KINGDOM AIC: P 045/2009
18-JUN-2009
AERONAUTICAL INFORMATION Safety
AEROPLANES INBOUND TO THE UK WITH FUEL RESERVES APPROACHING MINIMUM.
1 Incidents of crews reporting an inability to hold in the vicinity of their destination aerodrome prior to landing because of a shortage
of fuel have indicated a lack of understanding by operators and crews of the situation existing in busy UK terminal areas.
2 A number of aeroplanes appear to be approaching the UK with no more than minimum reserves of fuel. Aeroplane commanders who
determine, in flight, that their aeroplane will have little or no fuel above that which their company specifies as minimum reserves, should
establish that the weather conditions at the destination and alternate aerodromes fulfil specified criteria and that no delay is expected before, commencing an approach.
3 The information concerning delays that is passed to the crew by the controller is the best available at the time and takes account of
the expected volume of traffic at the aeroplane’s estimated arrival time. If the information available to the controller indicates a reasonably easy flow of traffic and Estimated Approach Times (EAT) are not being issued for the destination aerodrome, the response to request about delay will be ‘No delay expected’.
3.1 ‘No delay expected’ means in these circumstances:
‘Do not anticipate being required to remain in a holding pattern longer than 20 minutes before commencing an approach’.
3.2 Where a delay greater than 20 minutes is expected, the controller will pass an EAT. When delays are expected to be less than 20
minutes, controllers will, when requested, give a general indication of the expected delay.
4 Traffic situations in the terminal areas can change very quickly even though ‘No delay expected’ will often mean precisely that,
crews should expect that on occasions some holding will be required before they are fitted into the final approach pattern.
5 It is important, therefore, that operators and crews should take a realistic view of the amount of fuel required, to satisfy the minimum
fuel overhead destination requirements.
6 Crews should plan to arrive overhead a destination aerodrome with, at the very least, fuel sufficient to:
a Make an approach to land; and
b carry out a missed approach; and
c if a destination alternate aerodrome is required, fly to an alternate aerodrome, carry out the subsequent approach and landing;
and
d for aeroplanes with reciprocating engines, fuel to fly for 45 minutes; or for turbo-jet or turbo-prop aeroplanes, fuel to hold for 30 minutes at 1500 ft above aerodrome elevation in ISA calculated with the estimated landing mass on arrival at the alternate or the destination, when no alternate is required.
7 When the planned alternate aerodrome is in the same busy area as the destination, for instance Heathrow and Gatwick, the track
miles on which the fuel requirement for flying to the alternate is calculated should be realistically assessed taking account of the extended routing which can reasonably be expected during busy periods.
8 Pilots should also be aware that although every effort will be made to expedite their arrival, a call such as ‘Fuel Emergency’ has no
status in the UK and ATC cannot give priority to an aircraft with a shortage of fuel unless an emergency is declared.
9 A radio call prefixed by MAYDAY for distress or PAN for urgency will ensure priority handling but the aeroplane’s actual fuel state
should reflect the seriousness of the emergency call. A commander should only make such a call when he believes the aircraft to be in
danger, not because the fuel state has fallen below the amount needed to comply with formula given above.
10 For the future, it is not anticipated that any special procedure will be introduced for fuel emergencies but the Authority is considering
ways of providing more accurate forecasting of delays.