84
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What safety protocols did this Pythom Space rocket crew ignore?
The easy-to-spot stuff:
(assumed) Improper transportation of hazardous materials. Both white fuming nitric acid and furfuryl alcohol are considered hazardous materials; none of the vehicles in the ...
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63
votes
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Why is there a large wooden ball on Mariner 3's magnetometer?
I suspect the wooden sphere is a three-dimensional Helmholtz coil. A Helmholtz coil is a pair of circular coils, the radius of the coils should be equal to the distance of them. There is a coil pair ...
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57
votes
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Why is there any launch window at all for the Falcon Heavy test flight?
First of all, a typical launch window for going towards Mars is about 2.5 hours maximum. As a goal is to send the payload towards Mars, that is one limit to the window.
Also, there are a number of ...
- 121k
50
votes
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What is SpaceX doing differently with Starship to avoid it exploding like the N1?
One of the problems the N-1 faced was a lack of testing. They never did full up static fires, since the engines (NK-15) could only fire once after which valves needed to be replaced (multiplied by 30+...
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39
votes
Why don't we put an EmDrive in space?
EmDrive takes ~300W. You won't get it from a cubesat. You need over a meter of solar panels, or good 56kg of RTG battery.
It's been tested on Earth, made with materials and electronics meant to work ...
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39
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Why was AMOS-6 mounted on the rocket for a test fire?
The static test wants to be done relatively close to launch day, to minimize the likelihood of anything happening to the engines between the test and the launch.
The more conservative procedure is ...
- 166k
34
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Could Mars Rovers be lighter or faster if they didn't have to be tested on Earth?
The video shows only tests within the clean room on smooth clean test floors. The vibration test at first should simulate the conditions during launch.
Drive tests on a simulated Martian rough and ...
- 48.7k
32
votes
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What was NASA's Tire Assault Vehicle?
By the early 1990s the Space Shuttle Program had experienced some close calls with the landing and braking system, especially the tires. Hard data was desired about the response of the tires to ...
- 177k
30
votes
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Was Amos 6 insured for pre-launch operations?
Rewriting with clarification, I apparently misinterpreted the second tweet. Source still is this twitter feed (from a spacenews.com reporter).
The launch insurance doesn't count:
SpaceX explosion ...
- 7,216
27
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Why was the SpaceX abort test not initiated by real booster failure?
It was a real failure (albeit triggered externally rather than accidentally), just not the only failure that can happen. and it is the worst case of a series of the most likely failure scenarios: ...
- 593
25
votes
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How is sunlight simulated in spacecraft testing, given its brightness?
You can match the lux count of the sun, in a small area. The amount of solar power that shines on a satellite is about 1300 W/m2 in Earth orbit.
This is done at e.g. the ESA Large Space Simulator at ...
- 124k
24
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Why is there a large wooden ball on Mariner 3's magnetometer?
To add to Uwe's answer –
Aluminium is a bad material to wind coils around (like conductors in general) because any change in the current will for a while be “shadowed” by eddy currents. This can to ...
- 3,585
24
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Why no parachutes in the Orion AA2 abort test?
The test they were doing didn’t require parachutes. Data-taking ended right after the capsule separated from the tower. Since the capsule’s behavior after that was not part of the test, it could be an ...
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23
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How does NASA have permission to test a nuclear engine?
The nuclear test ban treaty bans testing nuclear weapons. It does not ban nuclear reactors. A nuclear rocket engine of the type proposed by NASA would be a thermal nuclear rocket:
https://en.wikipedia....
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21
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How does a simple construction keep a firing rocket on the ground?
I can answer this part "Has this same (or similar) design always been used for such tests?"
In the early days of the program Shuttle would occasionally do a pad test where the main engines were fired ...
- 177k
20
votes
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Why is the F9-029 Amos 6 case more complex than the F9-020 CRS-7 explosion?
Several issues have been reported informally, mostly in Elon Musk tweets.
Not as many cameras turned on as usual
Storage on site was damaged, and not all data was uploaded during test
This fueling ...
- 79.2k
20
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Why was the SpaceX abort test not initiated by real booster failure?
You seem to think they were testing in ideal conditions. That's as far from truth as you can get. The abort happened at the moment in flight with worst aerodynamical conditions (called maxQ), when ...
- 309
19
votes
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How does the Saturn V Dynamic Test Stand work?
I can answer the Shuttle part.
The test in question was the Mated Vertical Ground Vibration Test (MVGVT). Here's how the stack looked in the test stand.
Five configurations were tested
Liftoff
...
- 177k
19
votes
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How do engineers know new engines will work nominally once they reach space?
There are a number of vacuum test facilities available for testing engines in space and near-space conditions. The NASA White Sands Test Facility has several test stands for space and near-space ...
- 12.6k
17
votes
Why is there any launch window at all for the Falcon Heavy test flight?
Another minor factor in the timing of the launch is avoidance of other spacecraft and orbiting debris, as exemplified in a note posted on the Spaceflight Now mission update page for this test flight ...
- 586
16
votes
Does static fire reduce reliability?
Probably highly relevant here is the concept of the failure curve where parts will generally fail either at the start or end of life. Some engine designs may be such that they do not have much of an ...
- 20.9k
16
votes
What is SpaceX doing differently with Starship to avoid it exploding like the N1?
The design of the N-1 was constrained by available materials
There's nothing inherently wrong with having lots and lots of engines. In the N-1's case, this was not because they wanted lots of engines, ...
- 261
15
votes
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Testing flight characteristics before actual flight in model rockets?
For simple stability, you need the center of gravity to be in front of the center of pressure.
You can find the center of gravity by hanging the rocket from a string with a loop that slips along ...
- 177k
15
votes
Why no parachutes in the Orion AA2 abort test?
From the article:
Tuesday’s launch was more focused on testing the launch abort system itself. The parachutes on Orion have been tested 47 times.
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15
votes
Could Mars Rovers be lighter or faster if they didn't have to be tested on Earth?
Faster? No. The speeds of all Mars rovers so far have been limited by the navigation software or the available electrical power, not by physical capability. Spirit and Opportunity were both ...
- 14.1k
15
votes
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What does the ATOLL programming language look like?
The documentation for the Ground Operations Aerospace Language is much more available - search at ntrs.nasa.gov and a variety of reports come up.
An ACM publication (which apparently is not a journal ...
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14
votes
Will the January 2018 government shutdown affect the Falcon Heavy launch?
Currently unclear
According to the Verge:
It's possible that the [static fire] test could come early next week. But the Falcon Heavy’s launchpad is located at NASA’s Kennedy Space Center, and limited ...
- 2,540
13
votes
How does the Saturn V Dynamic Test Stand work?
It is indeed difficult to find information on this building. As you can see in the photo below, it was part of a massive test facility at Marshall Space Flight Center:
(Overview of MSFC; Mike Jetzer/...
- 13.9k
13
votes
Was the SK-1 spacesuit tested in flight prior to Gagarin's historic mission?
Прототипом первого космического скафандра СК-1 был высотный костюм «Воркута», разработанный для летчиков истребителя-перехватчика Су-9.
Важнейшей отличительной чертой стал шлем, который при падении ...
- 7,813
12
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Why no parachutes in the Orion AA2 abort test?
This is not a complete answer as I do not know the status of the parachute development, but here are some reasons a parachute is not needed:
Ejected Data Recorders:
These ~20 data recorders, ...
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