Responsive Access Small Cargo Affordable Launch (RASCAL ...

should be significantly more reliable that ELV launches. It was also assumed that the
first stage could land safely with two engines out, but fail to make the mission. This
would give the vehicle a thrust to weight of at worst 0.6 at takeoff, which is well within
the flight regimes of most fighter aircraft.
The upper stages of the RASCAL design were modeled in GT Safety with much
less aggressive numbers. The subsystem failure rates were taken at 80% of the ELV data
since the second stage will act as an ELV, just operating outside the atmosphere. It was
also assumed that the staging point would not be over a populate area. The resulting
numbers for the reliability and safety analysis are included as Table 8.
Table 8: GT Safety Outputs.
1st Stage
Loss of Mission MTBF 1 in 1094 Flights
Loss of Vehicle MTBF 1 in 6494 Flights
Casualty Rate
Upper Stages
0.0014
Loss of Mission MTBF 1 in 149 Flights
Loss of Vehicle MTBF 1 in 186 Flights
Casualty Rate
Total Vehicle
0
Loss of Mission MTBF 1 in 131 Flights
Loss of Vehicle MTBF 1 in 180 Flights
Casualty Rate 0.0015
As this table shows the MTBF for the first stage is very good with a mission failure only
once in 1094 flights. A loss of vehicle is even rarer with one occurring in 6494 flights.
The casualty rate of 0.0014 is also exceptional with only one accident occurring every
715 years. The upper stage is not nearly as reliable since it operates as a rocket rather
than an aircraft. The loss of mission every 149 flights with a loss of vehicle every 186
flights (80% of LOM failures are consider LOV). This reliability analysis results in an
overall launch system that will lose a mission every 131 flights, a vehicle ever 180
flights, and a man every 660 years. This loss of crew number is very high due to the
abort capability and ejection system built into the manned components of the vehicle
(first stage).
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