My work presentation on ETOPS: its meaning, applications and its associated thorough management system.

1. ETOPS

2. ETOPS
Extended Range Twin Engined
Operations
Kelvin Lam, Jul 2016

3. Background
Older aircraft...
Spot the similarity...?

4. Background
• Tri-/quad jet engines
• ↑ fuel consumption = ↑ cost of operation
• ↑ maintenance cost
• ↓ probability of all engines shutdown

5. Background
Newer aircraft...
Spot the similarity...?
Probably not much;
they are twinjets.

6. Background
• ↑probability of all engine shutdown
• Can be fatal!
• Nowadays, engine reliability ↑
• ↑Aircraft reliability
• ↑Longer range capabilities
• Therefore, mitigation plan possible:
ETOPS certification

7. Introduction
• ETOPS criteria defines maximum flight
duration with one-engine operating, at one
engine inoperative speed.
• From any plausible critical points, the A/C
must be able to land at a diversionary airfield
within the ETOPS permitted threshold.
• Threshold determined by:
A/C & engine manufacturer, aviation
authorities, IATA etc.

8. Diversionary airfields

9. 60-minute rule

10. 120-minute rule
ETOPS
black hole
Beginning stage of ETOPS

11. 138-minute rule
After 6 months on 120 mins operations, an additional 15% maybe granted

12. 180-minute rule
After 12 months on 138 mins operations, with good A/C & engine reliability, 180-
mins approval may be granted. This enables almost any commercial routes to be
flown.
To South
America

13. What has changed?
• Diversionary distance with 1 engine
operative (drag)
• Descend & cruise speed control
(maintaining FL and gentle slope that
gives best TAS)
• Critical fuel planning, taking engine
failure/depressurisation into account

14. What has changed?
Dispatch-wise...
• MNPS & RNP certification and
consideration (“perpendicular” to RSVM)
• Stringent MMEL  extra weight
• Additional failsafe navigation systems
• Weather minima requirement when route
dispatch

15. ETOPS critical fuel reserves
• In case of engine failure / depressurisation,
diversionary scenarios can be like this...
Very low
efficiency
for turbine
engines!

16. ETOPS critical fuel reserves

17. ETOPS critical fuel reserves
Gas Turbine Engine – Propulsive Efficiency

18. ETOPS critical fuel reserves
Higher fuel
burn to
compensate
reduced thrust
Gas Turbine Engine – Propulsive Efficiency

19. ETOPS critical
fuel reserves
*NB: not the same as Cost
Index / Performance Factor,
as this is a safety-critical
situation

20. Procedure
• Complete failure checklist
• Inform ATC
• Initiate descent
• Determine alternate airfield
• Divert using pre-planned diversion strategy
and speed profile, subject to actual
situational evaluation
• OFF Fuel X-Feed to faulty engine

21. Procedure
• OFF Air-Conditioning PACK (reduce
engine load)
• APU START (maintain blue hydraulic level)

22. Diversion distance
• Influential factors:
A/C Gross Weight at take off
ISA atmospheric / metrological condition
Diversionary FL = 170 (usual)
Never exceed speed: one-engine
VMO/MMO
Engine choice

23. Approval principle
• According to EASA AMC 20-6, three
criteria is defined to apply for ETOPS
approval
Type design approval
In-service Experience Approval/Continuing
Airworthiness
Operations Approval

24. Type-design approval
• Ensures that the aircraft type certification
provide...
Adequate system redundancy
Data supplied for safety assessments
Reliability of engine in IFSD situation (In
Flight Shut Down)

25. In-Service Experience approval
• Requires data from world A/C fleet &
engine to achieve necessary level of
engine reliability collectively
• Requires evidence of operator’s capability
to maintain & operate ETOPS aircraft
• Question to be considered:

26. In-Service Experience approval
• Requires data from world A/C fleet &
engine to achieve necessary level of
engine reliability collectively
• Requires evidence of operator’s capability
to maintain & operate ETOPS aircraft
• Question to be considered:
“How does the extra cost in ETOPS crew
training & hardware certification, justify fuel
saving cost in longer timespan?”

27. Operations approval
• Requires more stringent quality on engine &
APU (crucial for maintaining ETOPS
airworthiness)
• Restrictive MEL aircraft requirement
• ETOPS route may have reduced pool of
ETOPS-certified A/C due to maintenance
input
• Reputable & sound forward planning to
achieve no ADD (acceptable deferred defect)
target for ETOPS

28. Operations approval
• Significant system:
– Adversely affect safety of ETOPS flight when
failed;
– Its functioning is imperative to a safe diversionary
flight

29. Operations approval
• Significant system:
– Adversely affect safety of ETOPS flight when
failed;
– Its functioning is imperative to a safe diversionary
flight
FAIL! FAIL!
FAIL!FAIL!
FAIL!
FAIL!FAIL!

30. Mitigation
Type-design
approval
In-Service
Experience approval
Operations approval
Monitored by
EASA
Data
supplied
Airline
maintenance /
flight-ops
management
input
HOW?

31. ETOPS Management
Type-design
approval
In-Service
Experience approval
Operations approval
Monitored by
EASA
Data
supplied
Airline
maintenance /
flight-ops
management
input
ETOPS
MANAGEMENT
Evidence sent to EASA
from time-to-time...

32. ETOPS Management - airline
Closer fleet monitoring on
repetitive defects
ASRs
Regular ETOPS
meeting/engineering newsletter
Airline
maintenance /
flight-ops
management
input
ETOPS
MANAGEMENT
Mitigate many inter-related ADDs
(iceberg theory)
Above & beyond MEL standard

33. ETOPS Management - EASA
Monitored by
EASA
Data
supplied
ETOPS
MANAGEMENT
Monitors IFSD rates,
abnormal power thrust,
turnbacks/diversions.
Any other significant ETOPS
events

34. ETOPS Management
• When a problem is spotted, airline can
consider:
Performing less restrictive ETOPS route
Honour (most) ADD requests
Priority maintenance tasks
Call for meetings with stakeholders

35. ETOPS Management
• To remain ETOPS compliant, airline shall
demonstrate
– High standard of (paper-work from)
maintenance
– Low number of ADD
– Low number of faults
– Good monitoring & management systems

36. Conclusion
• ETOPS definition & meaning: flight duration,
critical point, diversionary
• Progressive approval: 60, 120, 138, 180,
beyond 180
• ETOPS certifying consideration: dispatch
route, critical fuel
• ETOPS approval: type-design, in-flight
service, operations
• ETOPS management: ADD/fleet monitoring,
ETOPS meeting