8.5 EDTO Flashcards
What does EDTO stand for
Extended Diversion Time Operations
What are the threshold times?
60 min for two engine AC
(ISA EO cruise speed)
180 min for 4 engine AC
(ISA all engine cruise speed)
Can the destination or Departure airport count as one of the EDTO alternates?
Yes
For flight plans based on EDTO max diversion times greater than 180 min what is different?
Wind and temperature conditions must be taken into account.
What are the distances for these times on 777-300ER?
60 NM
180 NM
240 NM
456 Nm
1327 NM
1765 nm
(ER: should no ERA be valid within 180 min, then 240 can be used)
(Distances shown on EFF)
Are critical fuel scenarios based on flight plan weight?
Yes. Also based on forecast atmospheric conditions (wind/icing)
EDTO critical fuel scenario assumes what?
At planned weight, enough fuel to:
- Fly to most critical point (EO, Depress or both)
- fly at speed defined on OFP to ERA
- 5% contingency (including APU/icing/CDL/MEL)
- hold for 15 min at 1500’ (minimum reserve fuel)
- approach and land
Dispatch requirements for EDTO
Dispatch will check weather/notams
MEL will indicate in AML if EDTO is affected by way of PADD (E)
If see EDTO, remember R FAW
(Dispatch check)
Routing (within max distance rings)
Fuel scenarios
AML (PADD’s)
Weather and Notams
Once in flight, who is monitoring progress of EDTO?
Pilots
Dispatch/flight tracker
IOC
Prior to EDTO entry point, ERA’s must be at?
Landing min
Crosswind within limit
(If goes below, need to find another suitable, if not flight shall not enter EDTO segment. But! PIC shall
Decide whether to continue or if fuel enough, reroute)
Flight within EDTO segment, what to monitor.
ERA weather.
If falls below landing min, attempt to find another.
Practically, you’d continue and use Wtv alternate avail.
Direct routings should be considered with care.
FCOM states “land at nearest suitable” and land ASAP.
Flight beyond nearest suitable only justifiable if all relevant safety factors taken into account. Some of them include?
Nature of malfunction.
Operational effect
Flight times to ERA’s
Preferred ERA’s vs EDTO era
Alt, weight and fuel
Weather
ATC
Terrain
Familiarity
If decide to divert, who should you let know?
ATC
IOC (as soon as practical)
Ism
(Note, diversion speed on ofp is for planning only…fly Wtv speed you like)
EDTO verification flight annotated how?
AML PADD and flight dispatch should be informed by ENG
What are the three scenarios to complete a EDTO verification flight?
Non EDTO flight
Non revenue
EDTO, but first 90
Min must be non EDTO
(BE SURE TO ENTER INto AML the success or result of verification)
If you ever get a EDTO verification flight, just pull up the relevant Actions required in 8.5.
Basically let Maintensnce know result after the 90 min and before entry.
Enter into AML after flight - completed
What is the definition of a 777 flying in EDTO?
Operating on a route to the point further than 60 minute fly time ISA still air conditions at one EO cruise speed
Can takeoff and destination airport be considered as enroute alternates for EDTO?
Yes
8.5.1
Is there any special requirements if the EDTO max diversion time is greater than 180?
Yes, usually consideration is using ISA and still Air
However greater than 180 minutes :
Forecast wind and temperature will be considered
Cargo fire suppression reduced by 15 min
ETO maximum diversion distances are cap calculated based on what aircraft configuration and what speed?
One engine in operative speed tables at VMO/MMO in ISA and still Air
Planning for a critical fuel scenario for ETO at the planned aircraft weight ensures there’s sufficient fuel to cover?
The more limiting of engine failure, depressurisation or both
Sent to required level
Cruise at Flight plan speed to an ERA (speed defined on OFP)
Descent to 1500 feet
Approaching Land +15 minutes fuel
What to do if prior to EDT entry point the weather falls below landing minimum at your ERA
8.5.5.2
Another Airport showing nominated within the maximum diversion distance
If not possible, Flight shall not enter EDT segment
PIC shall decide whether to continue or if fuel on board permits to do a reroute
