noise per seat or how to increase annoyance without really trying
DESCRIPTION
Noise Per Seat or How to Increase Annoyance Without Really Trying. Bill Swan Economist BOEING Commercial Airplane Group Marketing. Noise Per Seat Lowest for Small Airplanes. Noise Per Seat Lowest for Small Airplanes This is PER SEAT, not per departure. - PowerPoint PPT PresentationTRANSCRIPT
Noise Per Seat
or
How to Increase Annoyance Without Really Trying
Bill SwanEconomist
BOEINGCommercial Airplane Group
Marketing
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Noise Per Seat Lowest for Small Airplanes
Noise Per Seat Lowest for Small AirplanesThis is PER SEAT, not per departure
Bigger airplanes make more noise PER SEAT
not only is per departure noise higher, but so is per passenger noise
If you drive airports to fewer airplane movements per day
air travel moves to larger airplanes
total noise increases
This result is revolutionary
counter-intuitive for many
means limiting departures will increase noise
reducing noise will mean using smaller airplanes & more departures
Now, can we really explain how we got these numbers?
Movement Mix at AirportsTake 1% of the world’s scheduled passenger jet departures
Think of it as Amsterdam’s Schiphol airport in size
Short haul under 1600 kilometers; 3200 for widebodies.Night defined as after 2300 and before 0600.
Apply Stage 3 Departure Loudness
Stage 3 Noise Rule Translated to Seats
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Rule as UsedGross Weight Stage 3
Takeoff Noise for 2-Engine Jets
Total Noise Combines Loudness and FrequencyNoise is measure of Annoyance at one spot on the ground – one person listening
Day-Night Level (DNL) is total noise estimate:
one of several in common useimperfect but as sensible as any
DNL makes sense:
louder is worsemore frequent is worsemoving from 50 to 60 per hour not as bad as from 10 to 20adds 10 dB for night operations
)]10(86400
1log[10 10/epnl
s
sNDNL Ns is Number of departures of airplane size sepnl is the single-event noise level (with 10 added for night)
Noise Per Departure is Change in TotalNoise reduction for removing one departure
DNL value at start was 70.7 total for all movements on list
How much does total noise change for one departure?
Requires two DNL calculations and taking the difference
Noise Per Seat Divides by SeatsPer-seat measure is noise per passenger
These are the values plotted on the original graph
Normalized Against Their Own Lowest Available,Actuals Show the Same Pattern
Actual Noise for Big Planes is Worse
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Regulation Limits
Actual Noises
Consequences Are SurprisingIntuitions about departure frequency are misleading
Example: replace 2 departures at 125 seats with one at 250 seats:
total noise goes up 50%5-days-a-week at 250 seats makes same noise as twice-daily at 125large airplane/constant noise reduces air travel by 30%
Limits on departures will increase total noise:
if air travel is anywhere near original total seats
Noise reductions can be achieved by adding departures:
accompanies with reductions in airplane sizes used
Reducing noise at airports will require:
more departuressmaller airplanes
Frequency caps will increase total noise:
unless air travel is curtailed dramatically
Simple Measurements Do Not Reduce NoiseBut simple things will
83% of departures are narrow-body short-haul daytime:
they contribute only 28% of the departure noisebased on being 3dB quieter than long-haul levelsthese will be eliminated first with departure limits
1% of departures are wide-body long-haul night time:
they contribute 26% of the noisethese will not be the first to be eliminated
Drastic departure-reduction plan:eliminate all below 125 seats, plus 60% of 125-seatersreduces departures from 446 to 266
OR Reduce the wide-body sizes by one step (50 seats):
requires 6 more operations per day for same seat totalreduces noise the same as drastic departure-
reduction plan
Can Institutions Work to Reduce Noise?Political constraints can limit travel while increasing noise
Noise per seat higher for larger aircraft.
Noise certification levels miss lower short-haul noise levels in actual use.
Measures that miss these two effects will not limit noise effectively.
Can institutions develop measures that will?