22nd April 2010
“Aircraft Operational Fuel Savings & Noise
Reduction - Past and Future”
Captain Hugh DIBLEY MICLT, FRIN, FRAeS
DDCL & Royal Aeronautical Society
RAeS Aerospace 2010 – Hugh DIBLEY : “Aircraft Operational Fuel Savings & Noise Reduction - Past and Future” 1 /60
Aircraft Operational Fuel Savings & Noise Reduction - Past and Future
This paper was first given at CEAS in Manchester in October 2009
Paper was aimed to show pilots’ role in improving operational efficiency – given that:
Pilots’ role being fundamental to safety had been established throughout the airline
industry and that the travelling public regards pilots as essential.
However recent remarks that pilots can soon be removed from commercial airlines in
line with driverless trains in the foreseeable future without effecting safety are grossly
misleading to say the least.
Those who quote pilot error as a frequent final accident cause as justification for
removal of pilots must be unaware of the thousands of accidents routinely saved by
flight crews – evidenced by the Mandatory Occurrence Reports that operators are
required to submit which show when crews have had to deal with malfunctions or
abnormal events which could otherwise have led to accidents.
Technological improvements have undoubtedly improved safety such as • Improved navigation tools – DME, INS, GPS etc with presentation on glass screens
• FMS flying the aircraft accurately/efficiently - when programmed correctly
• Safety warning devices – GPWS/EGPWS/TAWS – which deal with symptoms not causes
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Aircraft Operational Fuel Savings & Noise Reduction - Past and Future
Given at CEAS in Manchester in October 2009
However these improvements used by pilots have been underlined by basic
Human Factors improving Pilots’ Performance:
Selection, Training, Crew Resource Management, Flight Time Limitations, etc
(I served on Sir Douglas Bader’s UK CAA Flight Limitations Board in the 1970s where rules
were based on a travel time from home of 1.5 hours and that crews were given suitable
accommodation close the airport when away on trips.)
Removal of any of these factors can/will lower safety
The safety performance of some Regional Airlines’ operating smaller
manufacturer’s aircraft versus Legacy airlines flying Airbus/Boeing is relatively
poor due to less robust operational support and control within airlines.
Colgan Air crash at Buffalo in 2009 –
• First Officer dead-headed in freighter cockpit across the USA SEA-NYC,
• Dozed in crew room prior flight, stated unwell/unfit prior to flight
• Lost Situational Awareness, after stall warning made inappropriate flap selection
The past lessons learned must not be forgotten/overlooked
Government oversight must ensure operators comply with the basic rules
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Aircraft Operational Fuel Savings & Noise Reduction - Past and Future
Given at CEAS in Manchester in October 2009
Considerations regarding removal of pilots from commercial aircraft:
Unmanned Aerial Vehicles’ accident record…….appalling
Aim?
Best Use of Technology to Reduce Fatalities – currently approximately:
• Airlines – 1K pa
• Roads – 40K pa
• Medical errors > 100K pa?
Driverless/remote vehicles –
Docklands Light Railway (optional driver), Paris Orly-Antony train, Toulouse Metro,
Airport Shuttles since 1960s?………..controls: stop/go, doors open/close
TGF/High Speed Trains/Eurostar have onboard drivers………….
With volcanic ash grounding airlines…….French railways were on strike for 10 days
EU funded project for pilotless commercial aircraft currently exists……
Is this really the most sensible use of current funds and technical expertise?
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Aircraft Operational Fuel Savings & Noise Reduction - Past and Future
Given at CEAS in Manchester in October 2009
These are “Busy” slides – for reading PowerPoint post lecture from DVD
Some slides use graphics from a 35mm slide presentation at the 1980 RAeS Flight
International Fuel Conservation Conference in this room 30 years ago to show some
basic factors never change.
The primitive drawing showing the current aspirations in the final slide indicates that
we have made some progress in 30 years!
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15.
Lecture Summary
Simplified Aircraft Flight Profile – for a Single Aircraft
Efficiency Loss as ATC must Separate Aircraft then Merge to Land
Pre-Flight Planning – Cost of Carrying Extra Fuel on the Sector
Departure Noise Abatement Procedures
Cruise - Fuel Savings & Crew Situational Awareness
Descent – Large opportunity for Fuel Savings
Approach – Large opportunity for Fuel Savings & Noise Reduction
Steep Approaches – to reduce noise?
Crews’ Ability to Save Fuel/Time by Choosing Approach & Runway
Past Examples of Operational Fuel Savings
Possible Future Operational Fuel Savings
“Future” ATM Fuel Savings Being Achieved NOW – USA
“Future” ATM Fuel Savings Being Achieved NOW - Europe
Accidents which Need NOT have Happened
Conclusion
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1. Simplified Aircraft Flight Profile – for a Single Aircraft
Single aircraft
Efficiency is reduced by the need for
ATC to separate aircraft to avoid
conflicts then merge again for landing
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2. Efficiency Loss as ATC must Separate Aircraft then Merge to Land
ATC often have to take aircraft away from their optimum route and altitude to separate
aircraft safely.
The distance between aircraft, and loss of efficiency, depends upon the navigational
accuracy of the total system – could vary from 3 miles under radar to 120 miles en-route.
Latest navigation systems can reduce en-route space to 5 miles.
ATC is split into separate centres, sometimes determined nationally, and liaison between
centres can reduce efficiency.
During descent aircraft may have to cross points between centres at specific altitudes
thus flying level rather than following an efficient continuous descent with idle thrust.
ATC Sectors in South East England, UK
ATC Sectors Los Angeles, USA
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2. Efficiency Loss as ATC must Separate Aircraft then Merge to Land
As aircraft approach their destination, ATC must merge aircraft into a stream to the
runway to achieve the most efficient landing rate.
At present this is usually achieved by ATC giving aircraft headings and speeds to fly at
low levels which stretch the approach path while aircraft are placed in sequence at the
required spacing for the type causing extra fuel consumption and noise over the ground.
New Air Traffic Management Systems will merge aircraft into their landing sequence
earlier in the flight, and allow more efficient descents with idle thrust leading to quieter
Constant Descent Approaches with no periods of level flight.
The complexity of the process to merge traffic efficiently can be seen from the aircraft
tracks into Schiphol airport at Amsterdam and simulations of the Paris arrival routes.
Simulation of Paris Arrivals
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3 Pre-Flight Planning – Cost of carrying extra fuel
Carrying extra fuel over the minimum flight plan fuel always
involves as penalty due to the extra weight burnt at 3% per hour.
The actual cost of extra fuel depends on the relative cost of fuel
between the departure and destination airfields.
If the fuel is cheap enough at the departure airfield it can be
worthwhile carrying/tankering extra fuel into the destination.
However the effect of the extra weight on the aircraft must be
considered – extra landing distance, possible extra brake wear
and use of reverse thrust, reduced maximum cruise altitude, etc.
This decision is best made by the crew on the day who need to
know the cost of extra fuel for the most economic judgement.
For example:
HKG-NGO Save $127/tonne – definitely worth tankering.
LHR-BRU Save $1/tonne – not worth tanking for fuel price alone.
HKG-DEL Cost £1/tonne – extra fuel could be cheap insurance if
delays en route were likely.
NGO-HKG Cost £206 – cost of extra fuel prohibitive.
Many companies do not publish Fuel Price Differentials but just
tell crews when to “tanker” fuel, which may not be efficient.
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4. Noise Abatement Departure Procedures 1 & 2
Early turbojet powered aircraft were extremely noisy on takeoff so had to climb steeply
to 3,000ft before accelerating to retract flaps and climb at the most efficient speed,
shown as NADP 1 in red.
Later fan jet engines with colder/slower exhaust streams made less noise so could
accelerate sooner and climb more efficiently shown as NADP 2 in green.
Noise close to the airport could be increased but was less than from turbojet aircraft,
and noise further out is reduced as the aircraft is higher than with NADP 1.
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4. Noise Abatement Departure Procedures 1 & 2
The noise foot print from current large fan jet aircraft is some 75% less than from
the early fan jet aircraft, therefore NADP 2 can be used at most airports without
causing significant noise disturbance close to the runway.
Yet some states specify that the less efficient NADP 1 be followed at airports where
urban noise reduction is not a factor.
This is causing significant amounts of unnecessary amounts of extra fuel to be
burnt and emissions released into the atmosphere at low level.
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4. A380 Aircraft & Engines Optimised for Low Departure Noise
Minimising aircraft departure noise is considered to be a critical factor in aircraft design.
Rolls-Royce increased the fan size of the Trent 900 for the Airbus A380 to comply with the
London Heathrow airport departure noise limits at the highest takeoff weight.
Airbus optimised the low speed performance of the aircraft and engine nacelle design and
minimised the airframe noise to make the A380 currently the quietest large jet aircraft.
After takeoff engine thrust is selected automatically for minimum noise on the designed
climb profile which produces the best compromise between climb rate and acceleration as
the aircraft gains altitude to create the minimum overall noise disturbance.
A380 airframe & engine designed to minimize noise
A380 Optimised Engine Thrust & Climb Profile
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5. Cruise - Fuel Savings by Making Maximum Use of Winds
The flight profile must
make maximum benefit of
the considerable energy in
the atmosphere.
The example shows times
when the wind component
over Western Europe
changed by 220 kts.
Flight planning systems
are fed with winds direct
from the forecast weather
models which can be
updated by information
from aircraft in flight and
fed back by AMDAR.
Aircraft Meteorological
DAta Relay was started by
the Australian Bureau of
Meteorology in the mid
1980s
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5. Cruise - Fuel Savings by Making Maximum Use of Winds
EUMetNet-AMDAR became part of EUCOS observing system headed by the Swedish
Met Service (SMHI) to manage the collective resources of the 10 contributing National
Met Services to deliver the best available quality of meteorological information
Wind, temperature &
possibly humidity data
from aircraft in flight –
currently Air FranceKLM, British Airways,
Finnair, Lufthansa &
SAS - is downlinked via
the ARINC/SITA
networks.
E-AMDAR uses the data
to update the weather
models which are sent
to users including
aircraft in flight.
However changing routes to take advantage of strong winds are not always possible
due to military or political reasons. Some oceanic routes still use fixed tracks with large
separation standards which can be reduced in future using improved ATM systems.
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5. Cruise - Fuel Savings by Making Maximum Use of Winds
Examples of Oceanic Routes – Some fixed, others are variable calculated by the ATC to
produce Organised Track Systems or by individual operators for their Preferred Routes
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5. Cruise - Fuel Savings by Making Maximum Use of Winds
An example showing an advantage of future ATM systems –
Separation across the Gulf of Mexico can be reduced from 15minutes/120 nautical miles
to 5 nm after ADS-B (Automatic Dependent Surveillance-Broadcast) has been enabled
which links aircraft FMS information with the Air Traffic Centres on the ground
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5. Cruise – Crews Need to be Aware of Aircraft Performance
Crews should be have a good knowledge of the performance of their aircraft such as:
Optimum speeds for minimum cost, minimum fuel, etc and the penalties for flying away
from the normal/recommended speeds.
Maximum altitudes for the aircraft weight and air temperature – All engines (provided by
the FMS) and if limited by engine thrust of airframe buffet (not shown by FMS).
Engine(s) Out altitude which may not be shown by the FMS with all engines running and
be only available from graphs which are difficult to read quickly.
Crews have climbed the latest aircraft with modern FMS above
the maximum recommended altitude and had to descend again.
Some aircraft have become upset with total loss of control.
Cruise Speed & Fuel Consumption Relationship
Engine Out Altitudes may
only be available on graphs
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5. Cruise – Crews Need to be Aware of Aircraft Performance
Table showing Boeing 747 Freighter Performance. All Engines and Engine Out
information is quickly available for use after loss of the FMS or flight instruments.
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5. Cruise – Crews Need to be Aware of Aircraft Performance
Table of Airbus A320 All Engines and Engine Out information showing the overall
capability of the aircraft – better than from an FMS. Data is available after system failures.
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6. Descent – Large opportunity for Fuel Savings – or Wastage
THERE IS NO TRADE BETWEEN FUEL & TIME DUE TO A POOR DESCENT
Summary of Penalties Cause by Poorly Executed Descents:
(Written in 1973 – some of us were worried about the environment then….)
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6. Descent – Large opportunity for Fuel Savings – or Wastage
Reduction of True Air Speed at Low Altitude at
the same Indicated Air Speed causes increase
in fuel consumption and flight time
Descending early wastes fuel and time, can
expose aircraft to icing conditions and more
aircraft traffic, makes more noise, etc
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6. Descent – Large opportunity for Fuel Savings – or Wastage
NASA B737 Descent Trials showed that a typically flown profile in line operation which
descended early burnt 40% more fuel than the NASA 737 while taking the same time.
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6. Descent – Large opportunity for Fuel Savings – or Wastage
Circular slide rule primarily designed to help
crews follow an efficient flight idle descent
profile to comply with an ATC clearance such
as to cross 23 DME XYZ at 8,000ft at 250kts.
Direct DME-Altitude checks are available
throughout to verify on the profile. A fixed
gradient of 400ft per mile above 10,000ft is
suitable for IAS of 300-340kts according to
aircraft weight, and 300ft per mile below
10,000ft is suitable for 250kts IAS.
Checking the profile mentally, normally by
300ft per mile, requires regular computation of
an equation, such as at 50 DME:
(50-8-23) x 300 = 5,700 + 8,000 = 13,700ft
In a survey BOAC B747 pilots estimated their
efficiency was improved by at least 10 miles
when using the computer, covering the cost of
the 2 provided on each aircraft in 1 flight.
Besides minimising fuel burn and noise,
following this profile improves safety by
keeping the aircraft well clear of the ground
into nearly all airfields.
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6. Descent – Large opportunity for Fuel Savings – or Wastage
United Airlines nearly bought the circular computer but while the fixed gradient was
suitable 747s & DC10s, DC9s found it too steep and B727s too shallow for their high speeds.
This linear computer has the altitude and sink rate on an elastic scale which can set
gradients from 250ft per mile for slow speed descents or when in a tailwind up to 600ft per
mile suitable for high speeds on a light aircraft into headwinds of 200kts. Could provide
smoother descents than A340 FMGEC but not worth the effort for reduced engine changes.
Aircraft FMS now fly efficient descents, but if taken off the planned route by ATC pilots can
be back to calculating the best profile using mental arithmetic.
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7. Approach – Critical for Fuel Savings & Noise Reduction
Approach is the phase of flight after descent when
the aircraft is decelerated and configured by
extending flaps for the final approach.
Ideally it is a short period of continuous descent.
ATC may need to give headings and speeds while
aircraft are merged into a landing stream, when
flaps and landing gear must be extended as late as
possible to minimise the extra fuel burnt.
Baseline Cruising at 37,000ft
The baseline of the table giving comparative fuel
consumption is when cruising at FL370/37,000ft.
Minimum fuel is consumed while descending
which shows that long slow descents with idle
thrust are the most fuel efficient.
Maximum noise and fuel consumption, 400% more
than at cruise altitude, is when flying level with
flaps and gear extended (500% on a B747), but
reduced when descending on the final glidepath
even with the extra drag of full landing flap.
Maximum Fuel Consumption
Minimum Fuel Consumption
This demonstrates that level flight should be
resisted if possible and that level flight with flaps
and gear extended should avoided at all costs.
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7. Approach – Critical for Fuel Savings & Noise Reduction
This shows that city life need not be disturbed significantly if aircraft are flown level with
minimum flap setting above 3,000ft, preferably at least 5,000ft, before descending on the
glideslope to the runway with gear up until about 1,500ft to be established for landing by
1,000ft.
(On Airbus aircraft the gear can be extended at 800ft, like the Space Shuttle, but this is not the approved procedure.)
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7. Approach – Critical for Fuel Savings & Noise Reduction
One operator into London Heathrow required the flaps and gear extension to be confirmed
in the Initial Approach Checklist which was completed when leaving the entry points to the
London area, so the aircraft could fly with the gear extended for up to 60 miles.
With the extra drag of the gear and flaps the aircraft would descend steeply and then fly at
low altitude across central London making conversation impossible when over flying.
Aircraft noise disturbance over central London was a significant factor in the 1971 decision
that the third London airport should be built 100km East of London on the Essex/North Sea
coast, but this project was terminated after the 1973-4 fuel crisis.
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7. Approach – Critical for Fuel Savings & Noise Reduction
To try and reduce the extreme levels of noise over
central London this article was published in the
GAPAN Journal of March 1974 (Appendix A in the
CEAS paper and at www.Dibley.eu.com.) Suggesting
that crews should ideally fly a continuous descent
from the entry point to intercept the runway
glideslope and extend the landing at about 1,500ft to
be stabilised in the landing configuration by 1,000ft.
The idea was accepted by UK NATS and after input
from Lufthansa who were proposing their similar
Managed Drag Procedure, Constant Descent
Approaches were started into LHR in 1975. DMEs
were installed to give crews continuous distance to
the runway paid for by the Department of Trade who
was responsible for Noise Abatement.
However CDAs into LHR were not implemented as
well as hoped as the procedure has yet to be
included in the manufacturers operating manuals.
While local operators are proficient less regular
visitors will tend to descent early to intercept the
glideslope from below.
Similar CDAs can be flown into airports like JFK immediately reducing noise on the approach.
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7. Approach – Critical for Fuel Savings & Noise Reduction
The type of CDA introduced into London and the
Netherlands can give worthwhile noise reductions
from 10 to 25 miles from the runway with no
additional technology, and are being implemented in
other airports such as Sacramento.
However at busy airports merging aircraft into an
efficient sequence for the approach can be more
difficult with aircraft trying to fly CDAs.
Future ATM systems due in service by about 2010
will allow efficient CDAs from cruise altitude, but
procedures using parts of this system are already
operating in some areas as described later.
UPS have been integrating their own aircraft flying
CDAs into Louisville, which is possible because
UPS is the only operator there at night.
Similarly because of their relatively low level of traffic the Swedish aviation authority
LFV have been developing “Green” 4D trajectories flying CDAs into Stockholm
Arlanda, both locally from and across the Atlantic.
However crews can still make savings using their own initiative.
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8. Crews Can Save Fuel/Time by Choosing Approach/Runway
Approach tracks into busy airports can be structured with a long lead in for bad weather,
and some are flown automatically to follow agreed noise routes.
When traffic and weather permits, crews should be allowed to fly shorter visual approaches
RAeS Aerospace 2010 – Hugh DIBLEY : “Aircraft Operational Fuel Savings & Noise Reduction - Past and Future” 31 /60
8. Save Fuel/Time Flying Constant Angle VOR-DME Approach
Advantage of Being Able to Fly a
Constant Angle VOR-DME Approach
Using DME-Altitude Table
To Confirm On Profile to the Runway
Nairobi Kenya – Main ILS Precision
Approach is to Runway 06,
after which a 10 minute Backtrack-Taxi is
Required to Airport Terminal
with hot bakes and heavy use of reverse thrust
DME-Altitude Table on Left chart allows
Non-Precision VOR DME Rwy 24 Approach
to be flown on a Constant Angle Approach to
the runway of near precision approach
accuracy –
with 3 mins taxi, cold brakes, idle reverse
Right chart has no table so a Constant Angle
Approach cannot be flown.
Aircraft must descend early and fly level
towards the runway – the cause of many
accidents.
The US did not introduce Constant Angle Non
Precision Approaches until after 2000.
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8. Save Fuel/Time Flying Constant Angle VOR-DME Approach
Continued Need for DME-Altitude Tables
A principle behind LHR CDAs is that crews
can calculate their required altitude on the
CDA profile when given Distance to Land.
Similarly from DME-Altitude tables on
charts crews can check progress down a
Non Precision glidepath to an accuracy of
some 30ft, making such approaches much
safer than the Step Down “Dive & Drive”
NPAs that have caused so many accidents.
India introduced Constant Angle Approaches in 2005
Jeppesen would not publish tables unless
provided by the airfield state. Tables are
now more available eg in India since 2005.
The US did not introduce Constant Angle
NPAs / DME-Altitude tables but relied on
the introduction of RNP approaches to
avoid the less safe “Dive & Drive” NPAs.
It will take time for RNP approaches to be
implemented worldwide and for all aircraft
to be equipped, so DME-Altitude tables
need to be retained until this is achieved.
VOR-DME type Approaches are being replaced by GPS
based RNP Approaches – but will take years to
implement worldwide, so DME-Altitudes tables will still
be required on charts to check the descent profile.
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9. Steep Approaches – to reduce noise?
Steep approaches were mainly operated by
quiet STOL turboprop aircraft and were
cleared to operate into short runway
airports close to city downtown areas.
London City Airport
Airbus have obtained approval for their
smallest aircraft the A318 to fly the 5.5º
approach into London City Airport.
To fly a steep approach on jet aircraft
requires extra drag and a switch on the
A318 changes the flight control laws to
extend some speedbrakes during the final
descent, and gives the pilot aural warnings
when to start the flare to land which is
made about 40ft soonerDame
than normal.
Ann Dowling
& Tom Hynes
The autopilot must be
disconnected
found
for thebefore
Silent Aircraft Initiative
reaching the minimum
altitude
when the Glide Slope Angle = 3.9º
Optimum
Approach
runway must be in sight which is higher
than for the normal 3 degree approach.
Steep approaches are not expected to be
possible by larger Airbus aircraft, but work
will concentrate on reduction of
aerodynamic noise during approach.
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10. Past Examples of Operational Fuel Savings
Example of 8% Immediate
Fuel Saving by Crews
Flight data recording showed
that an aircraft fleet was not
operating efficiently.
1979 prices
A fuel economy newsletter
listed the flight segments and
what how much extra fuel
was being burnt / could be
saved by a better operation.
The total extra burn was
possibly 26% but this was
unlikely to be saved as not all
items would occur on one leg.
After crews were made aware
of the penalties and some
changes in procedures an 8%
saving was achieved
immediately.
Departure/arrival procedures
in italics are not optimised in
current operations.
Potential Fuel Saving 26%
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10. Past Examples of Operational Fuel Savings
A contract was secured because the crews’ more
efficient operation saved 13% fuel compared to the
previous operator which covered the crews’ cost.
A cargo operator became profitable by, amongst
other savings, increasing payloads by reduced
fuel reserves and improved fuel consumption.
The Fuel Monitoring Graphs show how individual
crew performance can vary and affect the
profitability of an airline.
The top graph shows the cost of carrying extra
fuel based on the Sector Fuel Price Differential.
The centre graph shows the cost of extra fuel
burnt in flight, perhaps by non optimum operation
of the aircraft – descending early, configuring for
approach too soon, etc.
The bottom graph shows the total of the two. The
difference between the extremes is over U$400 per
sector which for a year could total U$100Ks.
Such information must obviously be used
sensitively and only be used for encouragement.
Crew Fuel Monitoring Graphs
Top – Cost of Extra Fuel Uplifted
Centre – Cost of Extra Fuel Burnt
Bottom – Crew’sTotal Extra Cost
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11. Possible Future Operational Fuel Savings
For more information in this section see paper by Phil Hogge at www.Dibley.eu.com
The large increase in air traffic will mean future fuel savings will primarily depend upon
the efficiency of the Air Traffic Management Systems.
Similar ATM systems are being developed by the European SESAR (Single European
Sky Airtraffic Research) and the US NextGen project which will incorporate:
•
•
•
•
Aircraft fitted with RNP (Required Navigation Performance) equipment which
monitors the accuracy of the aircraft navigation system and alerts if downgraded*.
Sharing of all navigational data between the “actors” in the system – aircraft, Air
Navigation Service Providers, airports, etc – enabling aircraft trajectories to be
coordinated efficiently by controllers on the ground and crews in the air.
Display of other aircraft in the cockpit so crews can share the air traffic separation
workload with the controller and participate in ASAS (Airborne Separation
Assistance Systems) such as self separation or following other aircraft in trail.
An Arrival MANagement system (AMAN) to sequence and merge aircraft by giving a
Controlled Time of Arrival to bring aircraft from cruise altitude in an efficient
constant idle thrust descent to a smoothly spaced landing flow to the runway.
* The improved accuracy of RNP systems will improve the safety/efficiency of individual
aircraft by allowing instrument approaches to all runways and eliminating the need
for Non Precision Approaches which have proved to be less safe.
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11. Possible Future Operational Fuel Savings
Improvement in Navigational Accuracy from the Self Monitoring RNP system
Example of Improvements in Accuracy from RNP Approaches into Kelowna BC
However the full benefits of RNP will not be achieved until the route
structure is reorganised to make use of the reduced separation possible
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11. Possible Future Operational Fuel Savings
Examples of RNP AR (Authorization Required) Arrivals & Departures
RNP AR approach to Zurich Runway 28,
Altitude 1,420ft
RNP AR Approach to Kathmandu
RW 02, Altitude 4,390ft
Where an RJ100 crashed in 2001 Flying a VOR-DME
approach with no DME-Altitude Table.
With steep terrain close to rw so difficult to construct
Constant Angle DME-Altitude Table for all approach.
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11. Possible Future Operational Fuel Savings
Examples of RNP AR (Authorization Required) Arrivals & Departures
Departure from Lhasa, Tibet, altitude 9,670ft, Surrounding terrain up to 20,000ft,
Minimum Safe Altitude 27,700ft. Considered World’s Most Challenging airfield.
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Video of *
China Airlines RNP AR Approach into Lhasa, Tibet
Using NAVERUS Equipment
* Requires NAVERUS .wmv video (31Mb) to run from PowerPoint, or .flv (9Mb) run from outside PowerPoint
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11. Possible Future Operational Fuel Savings
Airbus’ Progress towards Incorporating the Various Aircraft Systems
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11. Possible Future Operational Fuel Savings
Example of Aircraft Navigational Display showing Other Aircraft,
which can be used for Separation Assistance by the crew.
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11. Possible Future Operational Fuel Savings
Future SESAR plan for “Reference Business Trajectories”
RPTs will be stored in the airlines’ schedule, authorised by the Air Navigation Service
Provider and executed by the crew to comply with the Controlled Time of Arrival
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12. “Future” ATM Fuel Savings Achieved NOW - USA
UPS are already using their own ABESS (Airline Based En-Route Sequencing
and Spacing) system to enable their crews to fly efficient CDAs into Louisville.
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12. “Future” ATM Fuel Savings Achieved NOW - USA
UPS Operations Control uses ABESS to Sequence & Merge aircraft during Cruise
Communication systems & Displays in UPS aircraft then allow crews to manage
their own FDMS (Flight Deck Merging & Spacing) during an idle thrust descent.
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12. “Future” ATM Fuel Savings Achieved NOW - USA
Considerable reductions in Noise and Fuel have made by the UPS ABESS &
FDMS systems, enabling their crews to fly efficient CDAs into Louisville.
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13. “Future” ATM Fuel Savings Achieved NOW - Europe
In Sweden flights have been flying “Green” 4D trajectories
Weather data from preceding aircraft
is used to update the CDA profile for
the Green aircraft, which is then sent
to the ground. Aircraft land within
seconds of the FMS ETA with a
significant fuel saving. Work
continues to permit the system to
operate in times of heavy traffic.
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14. Accidents That Need Not Have Happened
The new RNP Approaches generally require an accuracy of 0.1 n mile…..
DME (Distance Measuring Equipment) reads to 0.1 n mile, therefore:
Altitudes on a 3 degree glidepath can be checked / flown to within 30ft (300 x .1)
(It is important to use the correct DME - ILS or VOR if both are available!)
A DME in line with a runway can show an accurate glidepath on a Non Precision
Approach by a simple DME-Altitude table for a Constant Descent Angle approach.
Step Down NPAs and many accidents could have been avoided 30 years ago.
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14. Accidents That Need Not Have Happened
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14. Accidents That Need Not Have Happened
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14. Accidents That Need Not Have Happened
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14. Accidents That Need Not Have Happened
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14. Accidents That Need Not Have Happened
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14. Accidents That Need Not Have Happened
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14. Accidents That Need Not Have Happened
Don Bateman of Honeywell
– The Father of EGPWS which shows terrain on the aircraft navigation display and
gives an earlier warning than GPWS so has further reduced the accident rate –
highlighted that 9 accidents in 2001-2002 could have been saved if EGPWS had
been fitted to the aircraft.
However 5 of the approaches had a DME available but charts
had no DME-Altitude for the crew to fly a Constant Descent Approach
DME Available for
Approach – but No
DME-Altitude table
to show Constant
Descent Approach
Angle.
It is unfortunate that the Flight Safety Foundation CFIT Task Force in the 1990s did not emphasise the
benefits of DME-Altitude tables to fly accurate Constant Descent Non Precision Approaches which could
have encouraged their use throughout the industry, and perhaps have saved accidents such as these.
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15. Conclusion – Make Use of New Equipment NOW!
I hope this presentation has given an insight into operational savings which can be
made by the Flight Crew.
On early less automated aircraft crews could make substantial savings if they made
best use of the information that was available to operate as efficiently as was possible
at the time, but on the other hand considerable waste and disturbance to the
environment could occur by operating away from the norm.
In due course the future sophisticated aircraft and ATM systems should be capable of
keeping the aircraft operation close to optimum, and with flight crews and ground
controllers working together this should enhance their understanding of each others’
roles and bring further benefits to the industry.
However many of the features of the systems can be used NOW – just as UPS
have implemented their in ABESS and FDMS to fly efficient CDAs into Louisville.
Why cannot the UK make better use of FMS 4D capability to give aircraft arriving
from the West a Required Arrival Time reduce to wasteful holding?
Why do not airlines campaign to use this facility? It is extraordinary to have an
aircraft fly for 13 hours from HKG and then hold because it is too early to land
before a time which has been published by the airport years in advance!
And for those engineers who still feel that pilots have already been designed out
of the system….
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15. Conclusion
….Remember….you still need a pilot press the buttons in the right order……
A380 Flight Deck
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15. Conclusion
….Maybe not - after all some say it’s just like driving a train!
French TGV driver on
record 575kph/357mph run
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Thank you for your attention
22nd April 2010
“Aircraft Operational Fuel Savings & Noise
Reduction - Past and Future”
Captain Hugh DIBLEY MICLT, FRIN, FRAeS
DDCL & Royal Aeronautical Society
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