CH4 Extended Diversion Time Operations Flashcards
What is the default threshold time for a twin engine aircraft vs a 3/4 engine aircraft?
Twin: 60 minutes
3/4: 180 minutes
What are the conditions used to determine the threshold distance?
OEI cruise speed
Still Air
ISA conditions
What rule part in NZ covers EDTO operations?
CAR 121
What is does CMP stand for? What is is?
Configuration, maintenance and procedures
Regulatory document that must be complied with for EDTO operations. it is produced by the manufacturer
What type of power plants must be used in an EDTO operation?
Turbine engines
What is the definition of an adequate aerodrome?
- Adequate length and strength
- An Instrument approach
- Approach and Runway lighting (incl PAPI/VASI)
- Rescue fire service of level 4 or equivalent
- ATC or AFIS
What is a suitable aerodrome?
An adequate aerodrome at which the weather is forecast to meet minimum requirements
What is the chance of an EDTO incident/accident?
“Extremely Remote”
less than 10^-8
What is the basic EDTO philosophy?
- To preclude a diversion being required, and
- To have programs in place protect the diversion if it were to be required
What things have been included in the preclude aspect of EDTO philosophy?
- Design enhancements to enhance reliability
- Systems designed/tested to ensure acceptable level of IFSD
- Maintenance and despatch requirements
- Engine condition and oil consumption monitoring
- Human error reduction in maintenance
What is a critical system?
One that in the event of a failure the QRH reads land at the nearest suitable airfield
What things have been included in the protect aspect of the EDTO philosophy?
- Pilots are knowledgable about about diversion alternate aerodromes
- Pilots have the ability to communicate with operator flight watch and ATC
- Aircraft has sufficient fuel and system redundancy
- Diversion airfield has facilities to protect pax from the elements
- Diversion airfield is suitable and will allow an approach to be commenced
What things does the CAA consider before granting EDTO approval?
- Type design (airframe/engine combo)
- Operator’s inservice experience
- Propulsion system reliability records
- Continuing surveillance of propulsion and airframe system reliability
What two certificates are required for EDTO certification?
- EDTO Type design approval
- EDTO Operation Certification
When EDTO is granted for more than 180 minutes EDTO what factors should be considered in the range circle plots?
- Actual/forecast winds
- Actual/forecast temperatures
- Limiting systems (usually cargo fire suppression system)
What is the FAA definition of in flight shutdown?
for EDTO only, “When an engine ceases to function (when the aircraft is airborne) and is shutdown, weather self induced, flight crew initiated or caused by an external influence”
What things does the definition on an IFSD exclude?
- when followed immediately by an automatic relight
- engine doesn’t produce the desired thrust but is not shutdown
What flights are included in IFSD data?
Every flight after the delivery of the aircraft
What is the max IFSD rate for 120, 180, 180+ EDTO?
120: Less than 5/100,000 engine hrs
180: less than 2/100,000 engine hrs
180+: less than 1/100,000 engine hrs
What period is the IFSD rate data gathered?
12 month rolling average
What is Air NZ’s policy when planning an EDTO operation?
To consider 3 stages:
- From departure to entering first EDTO
- From first EDTO entry until last EDTO exit
- From EDTO exit until destination
What fuel is required for an EDTO flight?
- Normal flight fuel (A-B, contingency, reserves)
- Emergency reserves (enough to divert from most fuel critical ETP in the EDTO segment to a suitable alternate and hold overhead for 15 minutes, and then conduct an instrument approach)
Describe how it is possible to see ETP diversion times that exceed the EDTO certification?
EDTO is not based on the same depressurised scenarios as ETPs are
What things should be done by flight crew prior to entering EDTO phases of flight? What should be done if they are inoperative?
- Serviceability for EDTO significant systems
- If U/S QRH, MEL and Flight operations should be referenced
What must the weather at the EDTO alternates be once the aircraft is airborne and in the EDTO region?
At or above the landing minima
What met minima must be met at EDTO alternates?
2+ precision Approaches
1 Precision approach
Non precision approach
2+ PA: 400ft or +200ft (above minima) ceiling, 1500m or +800m vis
1 PA: 600ft or +400ft ceiling, 3000m or +1500m vis
NPA: 800ft or +400ft ceiling, 4000m or +1500m vis
What different case considerations must be made when determining EDTO > 180min boundary ranges?
- Case 1: AEO
- Case 2: OEI
What are the conditions for calculating the Case 1 EDTO >180 min diversion?
Normal cruise speed Cruise Altitude Corrected for wind and temp Cargo fire suppression time limit - 15 minutes Shown as bold (red) line
What are the conditions for calculating the Case 2 EDTO >180 min diversion?
LRC (or stated higher) Drift-down altitude Corrected for wind and temp Most time limiting system - 15 minutes (excl cargo fire) Shown and thin continuous line
What is ‘Company Speed”? What is it used for? What is the value?
A higher OEI cruise speed to extend the Case 2 limiting distance
Entered into the FMC as CO Speed and is equal to 315kts IAS
What disadvantages will be meet due to using CO SPEED for the Case 2 cruise speed?
Increases ETP build up fuel
Fuel burn penalty due to increased weight
May affect payload capacity
What additional equipment are required for EDTO > 180 minutes than aren’t for less than 180 min?
APU
SATCOM voice
In what circumstance may an aircraft fly outside the flight planned area of operation on an EDTO segment?
If it is only slightly outside due to a weather diversion
