Figure 15: Cleaning of kinks for slower flights.

.  Adjustment of flight level
The method used consists of:
o
Dropping a flight leg if the slope in absolute value between two points is higher than 10000 ft.

o
Averaging the flight leg if the slope in absolute value is higher than 3000 ft but less than 10000ft. The absolute value of the slope of the previous leg is extended to the erroneous point but the sign of the flight leg slope is kept (Figure 16). This allows keeping the position of the point in terms of latitude and longitude but to smoothen the trajectory for compensating the erroneous flight level.

trajectories did not include flight level or presented inconsistent ground speeds due to successive positions recorded in a short period by different radar centres and rounded to the closest minute.
Table 28: Code system attributed to the zone indicator combinations.
Departure  En route  Arrival  Code 
C  F  C  0 
C  F  I  1 
C  D  C  2 
C  D  I  3 
I  F  C  4 
I  F  I  5 
I  D  C  6 
I  D  I  7 

. Creation of a table with necessary information for the merge.
The assessment finished; the information contained into the temporary flight table and the first and last legs information from the temporary flight leg table is imported into a temporary merge table (Table 29).
Table 29: Table MERGE_FLIGHT_INFO_TEMP.

Col #  Column Name  Data Type  Data Description 
1  OID  NUMBER(15)  Object Identifier for the flight 
2  CALLSIGN  VARCHAR2(15)  Flight’s callsign 
3  FLUID  VARCHAR2(21)  Flight unique identifier 
4  DEP_AIRPORT  VARCHAR2(5)  Airport of departure 
5  DEP_TIME  DATE  Time and date of departure 
6  ARR_TIME  DATE  Time and date of arrival 
7  FIRST_EVT  DATE  Time of the first event recorded 
8  FIRST_LAT  NUMBER(17,7)  Latitude of the first event 
9  FIRST_LON  NUMBER(17,7)  Longitude of the first event 
10  LAST_EVT  DATE  Time of the last event recorded 
11  LAST_LAT  NUMBER(17,7)  Latitude of the last event 
12  LAST_LON  NUMBER(17,7)  Longitude of the last event 
13  ASSESSMENT  NUMBER(1)  Number (0 to 7) attributed to the trajectory for assessing the quality 
14  MATCH_OID  NUMBER(15)  Object identifier used to match flights that must be merged 
16  ARR_AIRPORT  VARCHAR2(5)  Airport of arrival 

.  Identification of duplicated flights
The temporary merge table is scanned upon two criteria:

o
All flights that have the same FLUID are declared as duplicated.

o
Flights that have a different Fluid but the same callsign, departure airport and arrival airport can be duplicated if:

.  
Condition 1: The difference of time between the airports of departure of potential duplicated flights is inferior to 600 minutes.

.  
Condition 2 (Figure 17): The interval of time between the first event time of the reference flight and the last event time of the compared flight is less than 950 minutes and:

.  
The average speed between the first flight leg of the first flight and the last flight leg of the second flight is 0 or within 110 – 750 knots range.

.  
The average speed between the last flight leg of the first flight and the first flight leg of the second flight is 0 or within 110 -750 knots range.
　
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本文鏈接地址：AERO2K Flight Movement Inventory Project Report(26)