Mercury–Redstone - Vehicle use: Mercury
American sub-orbital launch vehicle. The Mercury–Redstone was developed from the Redstone intercontinental ballistic missile and manufactured by the Chrysler Corporation. It is comprised of a single core stage. The Mercury–Redstone was the first U.S. crewed launch vehicle.
source: https://www.nasa.gov/centers/marshall/history/mercury-redstone.html
Variant
MRLV
Launches
6
Failures
1
Realized
0.83
Predicted
0.75
50
51
53
52
55
56
54
57
58
59
60
61
62
64
63
65
67
66
69
68
71
72
70
73
74
75
76
79
77
78
81
80
83
82
85
84
86
87
88
89
90
91
92
93
95
94
96
97
99
98
01
00
02
03
04
05
06
07
09
08
11
10
13
12
15
14
17
16
18
19
20
21
22
23
24
11/21/1960 - Mercury Redstone
ABRUPT ENGINE SHUTOFF AT LIFTOFF
1st Mercury Redstone Launch
At liftoff the rocket ascended approximately four inches before the engine shut off, causing the vehicle to settle back onto the launch pad. The investigation revealed that two electrical cables separating in the wrong order caused the Redstone’s engine shutdown. One cable was a control cable providing various control signals. One was a power cable providing electrical power and grounding. Both cables were connected to the rocket at the bottom edge of one of its tail fins and would separate at liftoff. The lack of electrical grounding caused a substantial current to flow through an electrical relay, which was supposed to trigger normal engine cutoff at the end of powered flight. This relay tripped, causing the Redstone to shut off its engine and send a "normal cutoff" signal to the capsule.
SOURCES:
0.50
0.50
0.83
0.75
Realized Rate
Predicted Rate