SpaceX Crewed Dragon Solar Panels Change and Safety Modifications

NASA requires Boeing and SpaceX to demonstrate that there’s no more than a one in 270 chance for a fatal accident during a flight. The Space Shuttle program lost two shuttles in 135 launches.

John Mulholland, vice president and program manager for the commercial crew program at Boeing assessed three separate requirements, including the overall loss of crew as well as ascent and entry risks and loss of mission.

SpaceX and Boeing increased micrometeoroid and orbital debris protection.

Visually one of the biggest changes to the SpaceX Crewed Dragon is changing from solar panels on wings to having solar panels directly on the lower body of the spacecraft.

Long-road for NASA,Boeing and SpaceX to Safer Manned Flight

In September 2014, NASA awarded firm-fixed-price contracts to Boeing and SpaceX, valued at up to $4.2 billion and $2.6 billion, respectively, for the Commercial Crew Transportation Capability phase.

NASA, Boeing and SpaceX Report on Safety

There is a 52-page report from the Government Accountability Office on safety work and improvements by NASA, Boeing and SpaceX.

Boeing’s spacecraft—CST-100 Starliner—is composed of a crew module and a service module.
· The crew module will carry the crew and cargo. It also includes communication systems, docking mechanisms, and return systems for Earth landing.
· The service module provides propulsion on-orbit and in abort scenarios as well as radiators for thermal control.

In 2018, the Commercial Crew Program’s top programmatic risks identified for Boeing include challenges related to its abort system performance, parachutes, and launch vehicle.

SpaceX’s spacecraft—Dragon 2—is composed of a capsule, which we refer to as the crew module, and a trunk, which we refer to as the support module.
· The crew module is composed of a pressure section and a service section. This module will carry the crew and cargo. It also includes avionics, docking mechanisms, and return systems for a water landing.
· The support module includes solar arrays for on-orbit power and guidance fins for escape abort scenarios.

In 2018, the Commercial Crew Program’s top programmatic risks identified for SpaceX are in part related to ongoing design and development efforts related to its launch vehicle design, the Falcon 9 Block 5.

· Composite Overwrap Pressure Vessel: This Block 5 design includes SpaceX’s redesign of the composite overwrap pressure vessel, which is intended to contain a gas under high pressure. SpaceX officials stated the newly designed vessel aims to eliminate risks identified in the older design, which was involved in an anomaly that caused a mishap in September 2016. SpaceX plans to qualify the updated design for flight prior to the uncrewed flight test design certification review.
· Engine Turbine Cracking: The Block 5 design also includes design changes to address cracks in the turbine of its engine identified during development testing. NASA program officials told us that they had informed SpaceX that the cracks were an unacceptable risk for human spaceflight. SpaceX officials told us that they have made design changes to this Block 5 upgrade that did not result in any cracking during initial testing. However, this risk will not be closed until SpaceX successfully completes qualification testing in accordance with NASA’s standards without any cracks. As of March 2018, SpaceX had not yet completed this testing.
· Propellant Loading Procedures: Both the program and a NASA advisory group have raised SpaceX’s plan to fuel the launch vehicle after the astronauts are on board the spacecraft to be a potential safety risk.

17 thoughts on “SpaceX Crewed Dragon Solar Panels Change and Safety Modifications”

  1. True, but better late than never, and electric trucks should be much more prevalent in the next 5 years, especially in China where the government can mandate their usage to shorten the transition time.

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  2. I have been saying more freight needs to be moved via rail in the US for years. Clearly the same is true in China. Rail is typically about 6 times more efficient. Europe does a pretty good job of moving freight by rail.

    Addressing just the new trucks when China has half the trucks seems like a step taken too late. Those old trucks are going to used for a long time. Cleaning up the fuel is just a small step.

    Diesels can run fairly cleanly, but it means a loss of efficiency. That is why all those car companies were cheating on the tests. They wanted the fuel mileage, but you can’t have it without emitting a lot of crap.

    But when a company is considering a new truck and the new ones get worse fuel mileage than the old ones…they do not buy. Then the trucks just get older and older. Rebuild, rebuild again…

    I think China should try turbine-electric hybrid for trucks. They can burn diesel or just about anything and cleanly. A smidge more sound pollution, but it is higher pitched so it does not travel as far. And you can probably throw in some noise cancellation which is easier to do with higher frequencies. As long as you are making millions of trucks, turbines makes sense…economies of scale and all. Batteries, you always have the high materials cost…if you are using some sort of lithium battery. Turbines, though, can just be engineered well and mass produced.

    I think turbine-electric locomotives also make sense, but the gains would be smaller.

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  3. Tesla Semi would be an interesting match for such a road heavy infrastructure like china for all that long haul trucking.

    For more local delivery vans/trucks, frankly local EV manufacturers simply scaling out their hardware platforms to delivery van/truck size would be sufficient, and better leverages regen braking experience. With the huge electric bus push going on right now in china, the basic components for such an effort are effectively available now.

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  4. I’m surprised these proposed changes are so incremental. China’s political and economic system makes big change straightforward, and they’ve been making big changes to green the economy. They just completely electrified their bus fleet; why not completely electrify trucking and rail?

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  5. A 12% reduction in air pollution in Beijing is like going from “will kill you” to “most probably will kill you”…

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  6. Personal communication from people in Beijing does NOT indicate that the air is significantly better.
    And yes, they have private air quality meters.

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  7. A history of diesel engines may not lead directly to electric engine tech. But trucks have a lot of different systems: suspension, brakes, steering, chassis, trailer hitches, hookups, cabins, ergonomics, etc.
    The actual engine itself is only one of those.

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  8. Tesla is talking about a one million mile warranty. You cant get much more reliable than that. Also have a history with diesel engines does not help with electric motors.

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  9. Yep the Chinese government has consistently under reported the pollution levels. What they do report is enough for a national emergency.

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  10. Long haul with roughly 1MWh battery.

    Same truck with 200-500kWh battery for local.

    Or use big battery truck for local and just charge it once a week.

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  11. I thought that Tesla trucks were for long haul trucking. I mean that’s what Elon said they were for in his presentation.

    (Tesla trucks make the most economic sense in short haul trucking through stop and go traffic).

    Also Volvo is working on electric trucks. Given that Volvo is Chinese owned I would expect China to buy lots of Volvo trucks instead of Tesla trucks. Also Volvo has a long history of making trucks and so their trucks are probably going to be much more reliable compared to the alpha and beta release trucks Tesla will make.

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  12. This is where Tesla trucks can make a huge impact. The genius of the Musk is that he taken on two segments of the car industry where electrifying makes economic sense: Luxury and trucks. Buses is the a one but people in America don’t ride buses. Electric trucks can make more positive environmental impact than electric cars in the years to come.

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