For Questions That Don't Merit Their Own Thread

[CFYL]

We have solid refueling pipes on military planes, maybe you can add something like a household connector to "recharge" something. Or do a maneuver mid-air to get the dust off. That's dangerous and possibly not worth it.

[Gargamel]

Brushes.   Like on a slot car tracks cept the brushes point up in This case.    The drone has a circular port with concentric contacts for the brushes to touch, allowing it to land in any orientation.   Or some such “plugless” concept, perhaps landing on a guiding cone to line up the contacts perfectly. 
 

But of all we’re doing is cleaning some panels, we really don’t need a fan.    Just rotate them sideways and a small vibration motor knocks the dust off.   

[kerbiloid]

A pyramidal quad hex of solar panels to let the dust fall down.

Wait... Weren't the Pyramids covered with silicon panels?

Edited May 25, 2022 by kerbiloid

[Gargamel]

1 hour ago, kerbiloid said:

Weren't the Pyramids covered with silicon panels?

Only the sides that faced north.    

[kerbiloid]

50 minutes ago, Gargamel said:

Only the sides that faced north.    

Nope. They are between 23.5° latitudes, so they are illuminated from every side depending on the year season.

And as they are in the Northern hemisphere, they are mostly illuminated from South.

And look, they are placed enough far and not on the E-W or N-S direction from each other, so don't obsure the photovoltaic panels covering their surface (until the intrigued locals had scratched the cover off).

Spoiler

According to wiki, the "Khufu" surface area is 85 500 m2, so ideally it's ~85 500 * 1370 / 2 * 0.1 ~= 6 MW of solar energy (if a half is in shadow, and the panels are 10% efficient), 

Enough much power to power any equipment inside.

[SunlitZelkova]

7 hours ago, Gargamel said:

That was my first reaction too, but we do have a working flying drone on the planet, so maybe it’s not too far fetched an idea. 
 

But yes, as you mentioned, is the added mass worth the trouble?   This is a stationary lander.  It has probably done all then useful science it can, and is now basically a weather station.  How actually useful is an extended mission for a lander like this?  

Seismology. This requires sitting still in one place for a very long time. The seismometer doesn’t carry its own long range communications I think.

[Gargamel]

51 minutes ago, SunlitZelkova said:

Seismology. This requires sitting still in one place for a very long time. The seismometer doesn’t carry its own long range communications I think.

Ground weather vs air weather.   One is just slower.    Amounts to the same thing, primary and secondary missions are complete, anything left is just residual (but still useful) data gathering.  

[DDE]

So, we've lost the Zaporozhye nuclear powerplant thread a while back, and I have major questions.

 

Spoiler

https://www.wsj.com/livecoverage/russia-ukraine-latest-news-2022-05-25/card/u-n-atomic-agency-chief-presses-for-access-to-zaporizhzhia-nuclear-plant-g7vHkGVBMtlvYgYQPakd

All politics aside, the quantity and relative composition sounds wildly out of whack. Unfortunately, my attempts to measure just how much out of whack are stymied by the extreme variances in data. For example, if we were to compare to Japan's plutonium stockpile, we encounter three different estimates:

Up to 262 t, 21 t separated - http://www.ccnr.org/plute_inventory_99.html

46 t - https://mainichi.jp/english/articles/20210710/p2a/00m/0na/018000c

9 t described as enormous -https://thebulletin.org/2021/03/for-the-npt-to-work-plutonium-has-to-go/#post-heading

So, again, I'm more inclined than not to take the Ukrainian officials' angry rebukes that he discussed nuclear fuel...  and emphathize with the IAEA PR people who want to murder their boss for his loose tongue... but still, how do I make sense of the numbers that don't seem to be physically possible? From what I'm able to gather, plutnium normally isn't such a significant fraction of spent fuel.

Edit: quite interesting that he said something very similar on May 10 and roughly zero people cared https://www.world-nuclear-news.org/Articles/IAEA’s-Grossi-still-hopes-for-mission-to-Zaporizhz

Edited May 26, 2022 by DDE

[kerbiloid]

Myabe they mean not extraxted plutonium, still mixed in low concentration with spent fuel which is buried aside.

[DDE]

3 hours ago, kerbiloid said:

Myabe they mean not extraxted plutonium, still mixed in low concentration with spent fuel which is buried aside.

This was my best guess, but at a 4:3 ratio?

[LHACK4142]

A  rocket motor using a gas-generator cycle, according to Wikipedia, burns some fuel to produce gas which in turn powers fuel pumps. Pressure-fed motors rely on pressure to force the fuel out. However, I remember seeing something about a type of motor that produces gas, then moves it into the fuel tank, creating a sort of in-between. Does my memory fail me, or is this a thing?

[kerbiloid]

The liquid-fuel ICBM/SLBM and launch vehicles derived from them usually do this.

To provide gas pressure in the propellant tank.
But not to make the engine pressure-fed, just to prevent cavitation in the sink.

[DDE]

12 hours ago, LHACK4142 said:

A  rocket motor using a gas-generator cycle, according to Wikipedia, burns some fuel to produce gas which in turn powers fuel pumps. Pressure-fed motors rely on pressure to force the fuel out. However, I remember seeing something about a type of motor that produces gas, then moves it into the fuel tank, creating a sort of in-between. Does my memory fail me, or is this a thing?

It's not a subtype of engine cycle, it's an add-on feature. A lot of Soviet hypergolic staged-combustion motors have a divert feature like this. This explains why in a four-engine cluster you'd have one engine of a different model - it has the pressurization tap-off.

Edited May 27, 2022 by DDE

[SunlitZelkova]

What exact models of vehicles did the Soviets use for their astrovan?

What do the Chinese use?

[DDE]

3 hours ago, SunlitZelkova said:

What exact models of vehicles did the Soviets use for their astrovan?

Modified Lvov Auto Plant LAZ-695B (pictured - Gagarin's), -V and -E until Soyuz-11. LAZ-699P and -I until the mid-1980s. Then LAZ-5255 prototypes.

[kerbiloid]

(Rocket boosters are detached)

[steve9728]

13 hours ago, SunlitZelkova said:

What do the Chinese use?

Different cities have different buses. From the 50s to the 80s in other cities like Beijing or somewhere north, it was probably mainly copied from Skoda, modified Dodge cars, and it was not unheard of to convert to gas power when fuel was scarce. After that there were probably trolleybuses, conventional diesel,  natrual gas and now electric buses which have largely been completely replaced. 

And where I born and grow up, Shenzhen, didn't have a long history: this place is basically only 40 years old:

• https://www.bilibili.com/video/BV1d3411L74K?spm_id_from=333.999.0.0
• https://www.bilibili.com/video/BV12L4y1g7vi?spm_id_from=333.999.0.0
•  https://www.bilibili.com/video/BV1j34y197rv?p=25 (this one was the most I have ever take before the metros opened)

Damn thanks for those videos, homesick again

 

Edited May 28, 2022 by steve9728

[steve9728]

Saw something pretty... werid: Goalkeeper CIWS like air humidifier

SHUT UP AND TAKE MY MONEY!!

[DDE]

3 hours ago, steve9728 said:

Saw something pretty... werid: Goalkeeper CIWS like air humidifier

SHUT UP AND TAKE MY MONEY!!

As far as water dispersal goes... the NLAW storage case shower.

Spoiler

Anti-tank weapon packaging becomes tank. Ironic.

[kerbiloid]

It's trying to escape on the tree.

[JoeSchmuckatelli]

2 hours ago, DDE said:

packaging becomes tank

Grin!

... 

Man... I wished I had a tree way back when... Best I could do was a bucket. 

Trees are kewl. 

Also  https://preview.redd.it/v6181fma1zs21.jpg?width=640&crop=smart&auto=webp&s=ae24de8ee082f71718e65be9c410b5d45f9e0748

Edited May 29, 2022 by JoeSchmuckatelli

[kerbiloid]

15 minutes ago, JoeSchmuckatelli said:

https://preview.redd.it/v6181fma1zs21.jpg?width=640&crop=smart&auto=webp&s=ae24de8ee082f71718e65be9c410b5d45f9e0748

A luxury for sybarites.

***

"A tundra toilet: two (ski) poles.
On one you lean, with another one drive the wolves away."

[JoeSchmuckatelli]

9 minutes ago, kerbiloid said:

A luxury for sybarites.

***

"A tundra toilet: two (ski) poles.
On one you lean, with another one drive the wolves away."

Somehow I knew once I posted that - someone - would point out that life is harder in Siberia!*

Spoiler

(FWIW - I actually lived your story; Norovirus in Iraq, wild dogs fighting over my sick... and me having to repeat the process throughout one very long night.)

*well, in a lot of places.  Yankees really don't know how good we have it sometimes.

[steve9728]

16 minutes ago, JoeSchmuckatelli said:

*well, in a lot of places.  Yankees really don't know how good we have it sometimes.

Meanwhile some Chinese you don't know where they lying: at least they have [insert any 'luxury things']

When the Chinese say that your living conditions are really particularly tough, then you are really very tough. Similarly, when the British say your food is too awful...

[JoeSchmuckatelli]

3 hours ago, steve9728 said:

when the British say your food is too awful

Is 'boiled meat' still a thing over there?