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Comment: Re:Boeing bought more politicians. (Score 1) 127

by mtaff (#48011319) Attached to: Sierra Nevada Corp. Files Legal Challenge Against NASA Commercial Contracts

No one should be left out because there should be no contract. Instead, NASA should be fostering a spot market for launches. They should have a separate bid for each launch: "We want X satellite in Y orbit, and insured for Z dollars." Then give the launch to the lowest bidder. That way each company can work continuously to cut costs and improve services, knowing that if they leapfrog the competition, they can win the next launch, instead of being locked out for years.

For values of 'satellite' that include human-carrying s/c, and exlcude what would colloquially be called 'satellites'. And even if the contract was for a single launch, there would still be a contract, unless you are advocating for handshake deals.

Comment: Re:realities? (Score 1) 526

by mtaff (#17730822) Attached to: Running Your Electric Meter Backwards
The main safety issue is one of energy density, me thinks. It just isn't very bright to have 50kw (grabbing numbers) in a small device that is sensitive to, say, earthquakes. That is a lot of energy to control during during catastrophic destruction. I think part of the key to the safety issue is to have many smaller flywheels in an array where each flywheel is physically separated, and unlikely to cause a chain reaction.

Another option to examine is the merits of engineering in a fail-safe braking system (e.g. a 50kw electrical load) that could safely take some/most/all of the energy quickly. When a seismometer detects a large enough quake (or vibrations/heat indicating bearing failure), say 3.2 Richter, it hits the "brakes" and begins to turn motion into electricity to power this "braking" load. Wasting the stored energy in such a manner is better than risk of loss of the flywheel itself. This would essentially use the UPS-type design as an emergency braking system for a long-term storage design (for values of long-term approaching 14 hours).


A conference is a gathering of important people who singly can do nothing but together can decide that nothing can be done. -- Fred Allen