Tag: tests

The repairs to the cracks in the first Orion capsule have withstood static stress tests.

9:54 am

I’m so glad: The repairs to the cracks in the first Orion capsule have withstood static stress tests.

In addition to the various loads it sustained, the Orion crew module also was pressurized to simulate the effect of the vacuum in space. This simulation allowed engineers to confirm it would hold its pressurization in a vacuum and verify repairs made to superficial cracks in the vehicle’s rear bulkhead caused by previous pressure testing in November.

The November test revealed insufficient margin in an area of the bulkhead that was unable to withstand the stress of pressurization. Armed with data from that test, engineers were able to reinforce the design to ensure structural integrity and validate the fix during this week’s test. [emphasis mine]

I love how this NASA press release describes the cracking of the capsule bulkhead during the November testing, indicated in bold. “Insufficient margin”, eh?

Normally I am very forgiving when things fail during engineering tests, but for the bulkhead of this capsule to crack during these tests was actually pretty shameful, considering the decades of engineering work previously done in the building of space capsules and submarines. Things can certainly go wrong when you build something new, but I don’t see anything particularly revolutionary about Orion’s design. Lots of things might fail, but making sure the bulkhead could withstand the normal and well known stresses of spaceflight should not have been one of those things. The bulkhead failure suggests to me some sloppy engineering work took place in Orion’s initial design.

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ATK prepares for another test firing of its five-segment solid rocket motor.

9:31 am

ATK prepares for another test firing of its five-segment solid rocket motor.

The qualification campaign, led by rocket-builder ATK, will prove the solid-fueled motor is ready to help propel the Space Launch System from Earth on two test flights in 2017 and 2021.

Though obviously funded out of the Space Launch System program (SLS), there is no guarantee at this moment that ATK’s solid rocket will be used in these test flights. NASA has said that they are considering all options for picking the launch rocket.

In a sense, we are now seeing a side benefit produced by relying on independent and competing private companies to get into space. It has placed pressure on NASA and the companies building SLS to perform. Unlike in the past, when failure to produce a new rocket or spaceship meant that NASA would simply propose a new concept and start again, now failure will mean that someone else might get the work. The result: SLS might actually get built, for less money and faster.

Though I don’t see how NASA can possibly cut the costs down to compete with these private companies, their effort might succeed enough for Congress to keep the money spigots open until the rocket gets built.

Even as I say this I remain skeptical. Considering the federal budget situation, the politics of the upcoming election, and the strong possibility that private companies will successfully provide that launch capability at a tenth the cost, I expect that sometime in the next two or three years Congress will finally balk at SLS’s cost, and eliminate it.

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SpaceShipTwo’s First “Feathered” Flight

2:15 pm

SpaceShipTwo’s has successfully completed its first “feathered” flight.

After a 45 minute climb to the desired altitude of 51,500 feet, SpaceShip2 (SS2) was released cleanly from VMS Eve [WhiteKnightTwo] and established a stable glide profile before deploying, for the first time, its re-entry or “feathered” configuration by rotating the tail section of the vehicle upwards to a 65 degree angle to the fuselage. It remained in this configuration with the vehicle’s body at a level pitch for approximately 1 minute and 15 seconds whilst descending, almost vertically, at around 15,500 feet per minute, slowed by the powerful shuttlecock-like drag created by the raised tail section. At around 33,500 feet the pilots reconfigured the spaceship to its normal glide mode and executed a smooth runway touch down, approximately 11 minutes and 5 seconds after its release from VMS Eve.

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