49 CFR Appendix A
Maximum Allowable Curving Speeds
November 18, 2020
This appendix contains four tables identifying maximum allowing curving speeds based on 3, 4, 5, and 6 inches of unbalance (cant deficiency), respectively.
Table 1—Three Inches Unbalance
Open Table
Elevation of outer rail (inches) | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0 | 1⁄2 | 1 | 11⁄2 | 2 | 21⁄2 | 3 | 31⁄2 | 4 | 41⁄2 | 5 | 51⁄2 | 6 | |
Degree of curvature | Maximum allowable operating speed (m.p.h.) | ||||||||||||
0°30′ | 93 | 100 | 107 | 113 | 120 | 125 | 131 | 136 | 141 | 146 | 151 | 156 | 160 |
0°40′ | 80 | 87 | 93 | 98 | 104 | 109 | 113 | 118 | 122 | 127 | 131 | 135 | 139 |
0°50′ | 72 | 77 | 83 | 88 | 93 | 97 | 101 | 106 | 110 | 113 | 117 | 121 | 124 |
1°00′ | 65 | 71 | 76 | 80 | 85 | 89 | 93 | 96 | 100 | 104 | 107 | 110 | 113 |
1°15′ | 59 | 63 | 68 | 72 | 76 | 79 | 83 | 86 | 89 | 93 | 96 | 99 | 101 |
1°30′ | 53 | 58 | 62 | 65 | 69 | 72 | 76 | 79 | 82 | 85 | 87 | 90 | 93 |
1°45′ | 49 | 53 | 57 | 61 | 64 | 67 | 70 | 73 | 76 | 78 | 81 | 83 | 86 |
2°00′ | 46 | 50 | 53 | 57 | 60 | 63 | 65 | 68 | 71 | 73 | 76 | 78 | 80 |
2°15′ | 44 | 47 | 50 | 53 | 56 | 59 | 62 | 64 | 67 | 69 | 71 | 73 | 76 |
2°30′ | 41 | 45 | 48 | 51 | 53 | 56 | 59 | 61 | 63 | 65 | 68 | 70 | 72 |
2°45′ | 39 | 43 | 46 | 48 | 51 | 53 | 56 | 58 | 60 | 62 | 64 | 66 | 68 |
3°00′ | 38 | 41 | 44 | 46 | 49 | 51 | 53 | 56 | 58 | 60 | 62 | 64 | 65 |
3°15′ | 36 | 39 | 42 | 44 | 47 | 49 | 51 | 53 | 55 | 57 | 59 | 61 | 63 |
3°30′ | 35 | 38 | 40 | 43 | 45 | 47 | 49 | 52 | 53 | 55 | 57 | 59 | 61 |
3°45′ | 34 | 37 | 39 | 41 | 44 | 46 | 48 | 50 | 52 | 53 | 55 | 57 | 59 |
4°00′ | 33 | 35 | 38 | 40 | 42 | 44 | 46 | 48 | 50 | 52 | 53 | 55 | 57 |
4°30′ | 31 | 33 | 36 | 38 | 40 | 42 | 44 | 45 | 47 | 49 | 50 | 52 | 53 |
5°00′ | 29 | 32 | 34 | 36 | 38 | 40 | 41 | 43 | 45 | 46 | 48 | 49 | 51 |
5°30′ | 28 | 30 | 32 | 34 | 36 | 38 | 39 | 41 | 43 | 44 | 46 | 47 | 48 |
6°00′ | 27 | 29 | 31 | 33 | 35 | 36 | 38 | 39 | 41 | 42 | 44 | 45 | 46 |
6°30′ | 26 | 28 | 30 | 31 | 33 | 35 | 36 | 38 | 39 | 41 | 42 | 43 | 44 |
7°00′ | 25 | 27 | 29 | 30 | 32 | 34 | 35 | 36 | 38 | 39 | 40 | 42 | 43 |
8°00′ | 23 | 25 | 27 | 28 | 30 | 31 | 33 | 34 | 35 | 37 | 38 | 39 | 40 |
9°00′ | 22 | 24 | 25 | 27 | 28 | 30 | 31 | 32 | 33 | 35 | 36 | 37 | 38 |
10°00′ | 21 | 22 | 24 | 25 | 27 | 28 | 29 | 30 | 32 | 33 | 34 | 35 | 36 |
11°00′ | 20 | 21 | 23 | 24 | 25 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 |
12°00′ | 19 | 20 | 22 | 23 | 24 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 |
Table 2—Four Inches Unbalance
Open Table
Elevation of outer rail (inches) | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0 | 1⁄2 | 1 | 11⁄2 | 2 | 21⁄2 | 3 | 31⁄2 | 4 | 41⁄2 | 5 | 51⁄2 | 6 | |
Degree of curvature | Maximum allowable operating speed (m.p.h.) | ||||||||||||
0°30′ | 107 | 113 | 120 | 125 | 131 | 136 | 141 | 146 | 151 | 156 | 160 | 165 | 169 |
0°40′ | 93 | 98 | 104 | 109 | 113 | 118 | 122 | 127 | 131 | 135 | 139 | 143 | 146 |
0°50′ | 83 | 88 | 93 | 97 | 101 | 106 | 110 | 113 | 117 | 121 | 124 | 128 | 131 |
1°00′ | 76 | 80 | 85 | 89 | 93 | 96 | 100 | 104 | 107 | 110 | 113 | 116 | 120 |
1°15′ | 68 | 72 | 76 | 79 | 83 | 86 | 89 | 93 | 96 | 99 | 101 | 104 | 107 |
1°30′ | 62 | 65 | 69 | 72 | 76 | 79 | 82 | 85 | 87 | 90 | 93 | 95 | 98 |
1°45′ | 57 | 61 | 64 | 67 | 70 | 73 | 76 | 78 | 81 | 83 | 86 | 88 | 90 |
2°00′ | 53 | 57 | 60 | 63 | 65 | 68 | 71 | 73 | 76 | 78 | 80 | 82 | 85 |
2°15′ | 50 | 53 | 56 | 59 | 62 | 64 | 67 | 69 | 71 | 73 | 76 | 78 | 80 |
2°30′ | 48 | 51 | 53 | 56 | 59 | 61 | 63 | 65 | 68 | 70 | 72 | 74 | 76 |
2°45′ | 46 | 48 | 51 | 53 | 56 | 58 | 60 | 62 | 64 | 66 | 68 | 70 | 72 |
3°00′ | 44 | 46 | 49 | 51 | 53 | 56 | 58 | 60 | 62 | 64 | 65 | 67 | 69 |
3°15′ | 42 | 44 | 47 | 49 | 51 | 53 | 55 | 57 | 59 | 61 | 63 | 65 | 66 |
3°30′ | 40 | 43 | 45 | 47 | 49 | 52 | 53 | 55 | 57 | 59 | 61 | 62 | 64 |
3°45′ | 39 | 41 | 44 | 46 | 48 | 50 | 52 | 53 | 55 | 57 | 59 | 60 | 62 |
4°00′ | 38 | 40 | 42 | 44 | 46 | 48 | 50 | 52 | 53 | 55 | 57 | 58 | 60 |
4°30′ | 36 | 38 | 40 | 42 | 44 | 45 | 47 | 49 | 50 | 52 | 53 | 55 | 56 |
5°00′ | 34 | 36 | 38 | 40 | 41 | 43 | 45 | 46 | 48 | 49 | 51 | 52 | 53 |
5°30′ | 32 | 34 | 36 | 38 | 39 | 41 | 43 | 44 | 46 | 47 | 48 | 50 | 51 |
6°00′ | 31 | 33 | 35 | 36 | 38 | 39 | 41 | 42 | 44 | 45 | 46 | 48 | 49 |
6°30′ | 30 | 31 | 33 | 35 | 36 | 38 | 39 | 41 | 42 | 43 | 44 | 46 | 47 |
7°00′ | 29 | 30 | 32 | 34 | 35 | 36 | 38 | 39 | 40 | 42 | 43 | 44 | 45 |
8°00′ | 27 | 28 | 30 | 31 | 33 | 34 | 35 | 37 | 38 | 39 | 40 | 41 | 42 |
9°00′ | 25 | 27 | 28 | 30 | 31 | 32 | 33 | 35 | 36 | 37 | 38 | 39 | 40 |
10°00′ | 24 | 25 | 27 | 28 | 29 | 30 | 32 | 33 | 34 | 35 | 36 | 37 | 38 |
11°00′ | 23 | 24 | 25 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 |
12°00′ | 22 | 23 | 24 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 |
Table 3—Five Inches Unbalance
Open Table
Elevation of outer rail (inches) | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0 | 1⁄2 | 1 | 11⁄2 | 2 | 21⁄2 | 3 | 31⁄2 | 4 | 41⁄2 | 5 | 51⁄2 | 6 | |
Degree of curvature | Maximum allowable operating speed (m.p.h.) | ||||||||||||
0°30′ | 120 | 125 | 131 | 136 | 141 | 146 | 151 | 156 | 160 | 165 | 169 | 173 | 177 |
0°40′ | 104 | 109 | 113 | 118 | 122 | 127 | 131 | 135 | 139 | 143 | 146 | 150 | 150 |
0°50′ | 93 | 97 | 101 | 106 | 110 | 113 | 117 | 121 | 124 | 128 | 131 | 134 | 137 |
1°00′ | 85 | 89 | 93 | 96 | 100 | 104 | 107 | 110 | 113 | 116 | 120 | 122 | 125 |
1°15′ | 76 | 79 | 83 | 86 | 89 | 93 | 96 | 99 | 101 | 104 | 107 | 110 | 112 |
1°30′ | 69 | 72 | 76 | 79 | 82 | 85 | 87 | 90 | 93 | 95 | 98 | 100 | 102 |
1°45′ | 64 | 67 | 70 | 73 | 76 | 78 | 81 | 83 | 86 | 88 | 90 | 93 | 95 |
2°00′ | 60 | 63 | 65 | 68 | 71 | 73 | 76 | 78 | 80 | 82 | 85 | 87 | 89 |
2°15′ | 56 | 59 | 62 | 64 | 67 | 69 | 71 | 73 | 76 | 78 | 80 | 82 | 84 |
2°30′ | 53 | 56 | 59 | 61 | 63 | 65 | 68 | 70 | 72 | 74 | 76 | 77 | 79 |
2°45′ | 51 | 53 | 56 | 58 | 60 | 62 | 64 | 66 | 68 | 70 | 72 | 74 | 76 |
3°00′ | 49 | 51 | 53 | 56 | 58 | 60 | 62 | 64 | 65 | 67 | 69 | 71 | 72 |
3°15′ | 47 | 49 | 51 | 53 | 55 | 57 | 59 | 61 | 63 | 65 | 66 | 68 | 70 |
3°30′ | 45 | 47 | 49 | 52 | 53 | 55 | 57 | 59 | 61 | 62 | 64 | 65 | 67 |
3°45′ | 44 | 46 | 48 | 50 | 52 | 53 | 55 | 57 | 59 | 60 | 62 | 63 | 65 |
4°00′ | 42 | 44 | 46 | 48 | 50 | 52 | 53 | 55 | 57 | 58 | 60 | 61 | 63 |
4°30′ | 40 | 42 | 44 | 45 | 47 | 49 | 50 | 52 | 53 | 55 | 56 | 58 | 59 |
5°00′ | 38 | 40 | 41 | 43 | 45 | 46 | 48 | 49 | 51 | 52 | 53 | 55 | 56 |
5°30′ | 36 | 38 | 39 | 41 | 43 | 44 | 46 | 47 | 48 | 50 | 51 | 52 | 53 |
6°00′ | 35 | 36 | 38 | 39 | 41 | 42 | 44 | 45 | 46 | 48 | 49 | 50 | 51 |
6°30′ | 33 | 35 | 36 | 38 | 39 | 41 | 42 | 43 | 44 | 46 | 47 | 48 | 49 |
7°00′ | 32 | 34 | 35 | 36 | 38 | 39 | 40 | 42 | 43 | 44 | 45 | 46 | 47 |
8°00′ | 30 | 31 | 33 | 34 | 35 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 |
9°00′ | 28 | 30 | 31 | 32 | 33 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 |
10°00′ | 27 | 28 | 29 | 30 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 |
11°00′ | 25 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 |
12°00′ | 24 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 35 | 36 |
Table 4—Six Inches Unbalance
Open Table
Elevation of outer rail (inches) | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0 | 1⁄2 | 1 | 11⁄2 | 2 | 21⁄2 | 3 | 31⁄2 | 4 | 41⁄2 | 5 | 51⁄2 | 6 | |
Degree of curvature | Maximum allowable operating speed (m.p.h.) | ||||||||||||
0°30′ | 131 | 136 | 141 | 146 | 151 | 156 | 160 | 165 | 169 | 173 | 177 | 181 | 185 |
0°40′ | 113 | 118 | 122 | 127 | 131 | 135 | 139 | 143 | 146 | 150 | 154 | 157 | 160 |
0°50′ | 101 | 106 | 110 | 113 | 117 | 121 | 124 | 128 | 131 | 134 | 137 | 140 | 143 |
1°00′ | 93 | 96 | 100 | 104 | 107 | 110 | 113 | 116 | 120 | 122 | 125 | 128 | 131 |
1°15′ | 83 | 86 | 89 | 93 | 96 | 99 | 101 | 104 | 107 | 110 | 112 | 115 | 117 |
1°30′ | 76 | 79 | 82 | 85 | 87 | 90 | 93 | 95 | 98 | 100 | 102 | 105 | 107 |
1°45′ | 70 | 73 | 76 | 78 | 81 | 83 | 86 | 88 | 90 | 93 | 95 | 97 | 99 |
2°00′ | 65 | 68 | 71 | 73 | 76 | 78 | 80 | 82 | 85 | 87 | 89 | 91 | 93 |
2°15′ | 62 | 64 | 67 | 69 | 71 | 73 | 76 | 78 | 80 | 82 | 84 | 85 | 87 |
2°30′ | 59 | 61 | 63 | 65 | 68 | 70 | 72 | 74 | 76 | 77 | 79 | 81 | 83 |
2°45′ | 56 | 58 | 60 | 62 | 64 | 66 | 68 | 70 | 72 | 74 | 76 | 77 | 79 |
3°00′ | 53 | 56 | 58 | 60 | 62 | 64 | 65 | 67 | 69 | 71 | 72 | 74 | 76 |
3°15′ | 51 | 53 | 55 | 57 | 59 | 61 | 63 | 65 | 66 | 68 | 70 | 71 | 73 |
3°30′ | 49 | 52 | 53 | 55 | 57 | 59 | 61 | 62 | 64 | 65 | 67 | 69 | 70 |
3°45′ | 48 | 50 | 52 | 53 | 55 | 57 | 59 | 60 | 62 | 63 | 65 | 66 | 68 |
4°00′ | 46 | 48 | 50 | 52 | 53 | 55 | 57 | 58 | 60 | 61 | 63 | 64 | 65 |
4°30′ | 44 | 45 | 47 | 49 | 50 | 52 | 53 | 55 | 56 | 58 | 59 | 60 | 62 |
5°00′ | 41 | 43 | 45 | 46 | 48 | 49 | 51 | 52 | 53 | 55 | 56 | 57 | 59 |
5°30′ | 39 | 41 | 43 | 44 | 46 | 47 | 48 | 50 | 51 | 52 | 53 | 55 | 56 |
6°00′ | 38 | 39 | 41 | 42 | 44 | 45 | 46 | 48 | 49 | 50 | 51 | 52 | 53 |
6°30′ | 36 | 38 | 39 | 41 | 42 | 43 | 44 | 46 | 47 | 48 | 49 | 50 | 51 |
7°00′ | 35 | 36 | 38 | 39 | 40 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 |
8°00′ | 33 | 34 | 35 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 |
9°00′ | 31 | 32 | 33 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 |
10°00′ | 29 | 30 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 41 |
11°00′ | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 39 |
12°00′ | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 35 | 36 | 37 | 38 |
[78 FR 16113, Mar. 13, 2013]