Technical Provisions for Mode S Services and Extended Squitter

DRAFT - Working Paper ASP TSGWP11-01 for review by the TSG during the meeting in June 2011 in Paris
B-26 Technical Provisions for Mode S Services and Extended Squitter
A/V — L/W
code (Decimal)
ME bit
49
Length code Width code
ME bit
50
ME bit
51
ME bit
52
Upper-bound length and width for
each length/width code
Length
(metres)
Width
(metres)
0
0 0 0
0
15
11.5
1
1
23
2
0 0 1
0
25
28.5
3
1
34
4
0 1 0
0
35
33
5
1
38
6
0 1 1
0
45
39.5
7
1
45
8
1 0 0
0
55
45
9
1
52
10
1 0 1
0
65
59.5
11
1
67
12
1 1 0
0
75
72.5
13
1
80
14
1 1 1
0
85
80
15
1
90
If the aircraft is longer than 85 m or wider than 90 m, L/W Code 15 shall be used.
B.2.3.10.12 TRACK ANGLE/HEADING
Draft
The track angle/heading shall be a 1-bit (“ME” bit 53, Message bit 85) subfield of the ADS-B aircraft operational status
message (subtype=1, for surface participants) that allows correct interpretation of the data contained in the
heading/ground track subfield of the ADS-B surface position message. The bit values shall be interpreted as follows:
0 = Target heading angle is being reported.
1 = Track angle is being reported.
B.2.3.10.13 HORIZONTAL REFERENCE DIRECTION (HRD)
This 1-bit (ME bit 54, Message bit 86) subfield shall be used to indicate the reference direction (True North or Magnetic
North) for horizontal directions such as heading, track angle, selected heading, selected track angle, etc. The horizontal
reference direction subfield shall be encoded as specified in the following table:
DRAFT - Working Paper ASP TSGWP11-01 for review by the TSG during the meeting in June 2011 in Paris