When do you need a take off alternate?
If you cannot get back to your departure Aerodrome due to weather or performance reasons.
Where should a take off alternate be located and what is different for ETOPS?
Within 60 minutes flying time (400nm) in still air standard conditions at the one-engine-inoperative cruising speed.
For ETOPs approved aeroplanes and crews, additionally, for all states EXCEPT USA and Saudi Arabia:
within 120 minutes flying time (800nm) in still air standard conditions, or the approved ETOPS diversion time if this is less, at the one-engine-inoperative cruising speed based on the actual takeoff mass.
What minima apply for take off alternates in UK?
Normal operating minima
What is different for take off alternates for these 3 countries:
USA, Canada and Saudi Arabia?
The T/O alternate must be above the country alternate minima.
OMA 8.2.6 b, c and d
What criteria must you satisfy to dispatch without a destination alternate?
a) Flight time less than 6 hrs
b) 2 independent runways
c) Visibility ETA +/- 1 hr = 5 km
d) Cloud ceiling ETA +/- 1 hr = 2000' or circling + 500' whichever is the greater
e) Increase reserve fuel by 50% ie 15 mins holding at 1500 ft
OM A 8.18.8
What are the criteria for a destination alternate and when would you be required to select 2?
a) BA policy always to have one
b) 2 destination alternates are required if destination weather conditions will be below planning minima +/- 1hr of ETA OR no met is available
What is the difference between a fuel alternate and a commercial alternate?
Fuel alternate = diversion unlikely
Commercial alternate = diversion is likely
What is the reason for an enroute alternate - ERA?
To reduce contingency in the event there is no SCF data ie to reduce from 5% to 3% of trip fuel
See contingency fuel OMA 8.18.10
It must satisfy the EASA geometry and use planning minima / application of forecast conditions table (AFC)
OMA 8.2.5.i, m and q
What are the planning minima step down criteria for destinaltion alternates and ERAs?
What are the planning minima requirements for :-
- Destination alternates
- Isolated destination alternates
Norm operating RVR limits. For NPA or circling approaches, cloud ceiling at or above the minum on the IAC
Planning minima apply (step down policy eg Cat 3 to Cat 1, Cat 1 to NPA minima etc)
OMA 8.2.5.p and q and AFC table OMA 8.2.5.m
Planning Minima for Non UK airfields - which countries have special rules for TO and destination alternates?
Australia, Canada, Saudi and USA
Which 2 manuals are the ETOPs requirements and guidance split between?
OMA 8.21 and OMB 2.29
The normal fire and rescue category for the B777 is XXX
What is the category required for ETOPS en route alternates?
Normal 777 = 9
ETOPS = 4 with 30 minutes notice
B777 performance Manual 1.3
Define an ETOPS adequate airfield (7 points)
It will have the necessary:-
1) Air traffic services
4) wx reporting
5) Nav Aids
6) Emergency services
7) at least 1 instrument approach
What is the rule distance and time for ETOPS?
1200 nm and 180 minutes
How many electrical generators are required for ETOPS Dispatch of a B777?
3 are required
What are the requirements for ETOPS En route alternates
1) LDA of expected runway is adequate for forecast conditions/state
2) Instrument approaches are available for the expected runway
3) Forecast from ±1 hour earliest/latest ETA meets the planning minima and crosswinds (incl gusts) are within limits (accounting for runway condition and visibility)
ETOPS Planning Minima (OM A 8.21.5)
precision approach: DA + 200', RVR/VIS + 800m
NPA/Circling: MDA +400', RVR/VIS + 1500m
4) FCB should also give information on airfields that are appropriate to the route but don’t meet the forecast criteria
Once you have dispatched, what minima is required at the ETOPS alternates?
Normal operating minima
ETOPS critical fuel reserves are calculated from 3 different scenarios.
What are they?
1) Depressurisation, followed by a descent to 10,000 ft and a 2 engine diversion
2) Depressurisation and a descent to 10,000ft + Engine Failure and a single engine diversion
3) Eng failure followed by a diversion.
NB: upon reaching the alternate, fuel is required to hold at 1,500ft above field elevation for 15 minutes. Wind and icing allowances are made.
Much detailed info - see OMA 8.21.9
What is the validity of a B777 ETOPS Transit check?
What happens if you return to stand after the initial departure?
Validity = within 4 hrs of the scheduled departure time.
Return to stand - no need to repeat ETOPS transit check unless the aircraft nightstops.
B777 transit check instructions
What runway state would negate an airfield being used as a takoff alternate?
DURING FLIGHT PLANNING FOR LANDING AT AIRFIELDS WITH CONTAMINATED OR SLIPPERY CONDITIONS, THE RUNWAY SHOULD NOT BE USED IF FULL REVERSE CANNOT BE OBTAINED FROM ALL ENGINES.
B777 Performance manual 3.5
However, post dispatch, following an engine failure an aircraft can return/continue to a contaminated or slippery runway using QRH PI Section, Non Normal Config Ldg Eng Shutdown tables to check adequate runway length available
When would you need to perform an Alleviated ETOPS transit check?
Where would you find out how to do it?
When there is no BA authorised Engineer at the departure Aerodrome eg following an unscheduled diversion to a non BA station
To be used on authority from Maintrol
AML user guide
ETOPS verification flights are carried out if required by OMA 8.21.13.
What action is required by the commander?
1) An ADD is raised in the AML 'ETOPS Verification flight required' and the reason
2) Commander records in action taken 'ETOPS verification flight satisfactory'