williatw wrote:
"Thought" they can be re-used isn't the same as data.
Ironic from someone singing the praises of a Power Point rocket.
From
The Rocket Company by Patrick Stiennon and David Hoerr "An off-the-shelf RL10A3-3A, with 16,500 pounds of thrust has been run for over 30 minutes without any maintenance. Pratt & Whitney is confident that one of their RL10s could make 25 flights before some maintenance might be necessary on the bearings and the gear train and perhaps 100 flights before the gear train would need to be rebuilt . The ultimate life of the current engine design was estimated to be about 130 flights, based on cryogenic thermal cycling of the bell."
williatw wrote:But consider this: lets assume for the sake of argument that a Triton NTR can only be used a max of 5X times(there & back)
You haven't provided a shred of evidence this vehicle would be reusable at all.
What points is it moving between? Low Earth Orbit and Low Mars Orbit? What is the delta V budget of this vehicle? You still haven't given me temperature in the rocket engine. No numbers, just hand-waving.
williatw wrote:before it is toast, but a chemical rocket can be re-used let us say 25 times (there and back). Considering the much greater SI of NTR 800-1200s vs 450s for a chemical rocket in a given block of lets say 12 years, and you and I were competing shipping companies. Who could haul the most cargo to Mars at a profit?
"Mars" and "profit" in the same sentence? We're not on the same page.
williatw wrote:I can haul more cargo per trip, my launch windows are wider than yours so I can launch more often because I have more DeltaV, and my trip times are faster. I can use the same propellant banks as you can but haul how many times the payload(at a profit) than you can in a given block of time. Even though my shipping cost are higher than yours because of my less re-usable system, in a given block of time I would make more profit than you would because of greater cargo volume.
EML1 has a 2.4 km/s advantage over LEO. Given a fully fueled and stocked ship departing from EML1, chemical also has wide launch windows and the option of shorter trip times.
Given water and and air at EML1, it becomes possible to provide adequate radiation shielding and extra consumables for the crew. An 8 month trip is no longer a suicide mission. This would lessen the need for short trips.