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Perianne
08-18-2015, 09:48 AM
Who can answer military-type questions?

I have a couple, but will start with this one:

When a bomber drops its payload, do they calculate in the turning of the earth?

darin
08-18-2015, 09:53 AM
They don't. has no effect on accuracy, due to the very short-time the bombs fall. Plus, the Plane is moving too - like when you are in a car and drop a french fry, the fry drops exactly down between the seats - no leading required.

NightTrain
08-18-2015, 09:57 AM
Yeah, besides that all the new ones are guided, so they'll steer to target even with winds pushing them off course.

I don't think we're even using the WWII era 'dumb bombs' anymore.

Perianne
08-18-2015, 10:16 AM
I should have said that I was referring to WWII high level bombing, at say, 20,000 feet.


Wouldn't it take 30 seconds or so for the bomb to hit the ground? If the earth is moving at 1,000 miles per hour, that is about 17 miles per minute, or 8 miles in 30 seconds.

I suppose I don't understand why they would not have to calculate the fall time.

NightTrain
08-18-2015, 11:08 AM
Good question.

Artillery, Naval Gunnery and snipers take it into consideration for long shots, but I'm not finding anything for bombers. I would guess that it's because you're directly overhead instead of laterally away from the target, and the big variables in WWII for that was making sure the plane was absolutely level and accounting for winds. The bomb sights at the time didn't take Coriolis Effect into consideration.

https://en.wikipedia.org/wiki/Norden_bombsight

jimnyc
08-18-2015, 11:08 AM
Suppose you hold up a marble, in a wind proof room, about 20 feet high. Next to it, you hold up a steel weight, about 500x the weight of the marble.

Which one moves faster and which one hits the ground first?

(sorry for OT, but it's sorta not OT to an extent. I just recall this question/experiment from my physics class. I normally can't remember more than 20 minutes ago. This was like a million years ago!).

Perianne
08-18-2015, 11:19 AM
Good question.

Artillery, Naval Gunnery and snipers take it into consideration for long shots...

That was my second question, about snipers.

Perianne
09-01-2015, 10:23 AM
Who can answer military-type questions?

I have a couple, but will start with this one:

When a bomber drops its payload, do they calculate in the turning of the earth?

My second question:

I have a friend who is wanting to join the military eventually. She talks about a program where the military will pay for her schooling to become a nurse, and then she must serve. She is interested in a career, not just the minimum time of service.

My question is this: how would that work? What rank could someone in her position eventually achieve?

Gunny
09-01-2015, 10:30 AM
I should have said that I was referring to WWII high level bombing, at say, 20,000 feet.


Wouldn't it take 30 seconds or so for the bomb to hit the ground? If the earth is moving at 1,000 miles per hour, that is about 17 miles per minute, or 8 miles in 30 seconds.

I suppose I don't understand why they would not have to calculate the fall time.

WWII hig level bombing was "carpet bombing". They had a Norton sight, high tech in its day, but they used paper maps for recognition. A Huey Supercobra carries more firepower nowadays than a B-17 did in WWII.

As NT said, it's all laser guided. If you got the grid coordinates you can drop a bomb in a hat.

But I DO like WWII fighters/bombers. My great uncle felw a P-47,my grandfather flew a P-39. and my other grandfather was part of the Big Red One. Not that everyone in my family's military, or anything.:laugh:

Noir
09-01-2015, 10:41 AM
The earth is rotating on its axis, but this includes the atmosphere that the plane is in.

If a plane was stationary at 20,000 feet, the earth would not be moving beneath it. You would only have to take into account details like the turning of the earths axis if you were completely outside of its sphere of influence, i.e. firing a rocket form the moon at the earth.

Gunny
09-01-2015, 10:50 AM
The earth is rotating on its axis, but this includes the atmosphere that the plane is in.

If a plane was stationary at 20,000 feet, the earth would not be moving beneath it. You would only have to take into account details like the turning of the earths axis if you were completely outside of its sphere of influence, i.e. firing a rocket form the moon at the earth.

Doesn't matter. You got a guided missile and a target, the missile moves with the target. Where the Earth is is irrelevant.

Now you want to get some trajectory in, a .308 (7.62 mm) boattail is 8 clicks up and one click right at 1000 m on an M-14A1 with a 30x Unertl scope. Guess the world ain't spinning fast enough.

jimnyc
09-01-2015, 11:14 AM
Suppose you hold up a marble, in a wind proof room, about 20 feet high. Next to it, you hold up a steel weight, about 500x the weight of the marble.

Which one moves faster and which one hits the ground first?

(sorry for OT, but it's sorta not OT to an extent. I just recall this question/experiment from my physics class. I normally can't remember more than 20 minutes ago. This was like a million years ago!).

Answer you bastards!! :poke:

Perianne
09-01-2015, 11:21 AM
Answer you bastards!! :poke:

They will both hit the ground at the same time.

Gunny
09-01-2015, 11:26 AM
Answer you bastards!! :poke:

We have issues. :)

Just lead them a bit.

jimnyc
09-01-2015, 11:50 AM
They will both hit the ground at the same time.

Well that was rather anti-climactic. :( But of course you are correct!

Gunny
09-01-2015, 11:53 AM
Well that was rather anti-climactic. :( But of course you are correct!

I'm trying to figure out why there's Bee Gees on my speakers ......

Noir
09-01-2015, 11:57 AM
Suppose you hold up a marble, in a wind proof room, about 20 feet high. Next to it, you hold up a steel weight, about 500x the weight of the marble.

Which one moves faster and which one hits the ground first?

(sorry for OT, but it's sorta not OT to an extent. I just recall this question/experiment from my physics class. I normally can't remember more than 20 minutes ago. This was like a million years ago!).

The only value that could change the speed at which both objects fall is air resistance, caused by the friction between the object and the air against its surface.

If there is no air in the room then they will fall at the same rate (mass by gravitational constant)
If there is air then the rate will change based on the thickness of the air, the thicker the air the greater of a difference will be, with the object of most mass hitting the ground first.

jimnyc
09-01-2015, 12:00 PM
The only value that could change the speed at which both objects fall is air resistance, caused by the friction between the object and the air against its surface.

If there is no air in the room then they will fall at the same rate (mass by gravitational constant)
If there is air then the rate will change based on the thickness of the air, the thicker the air the greater of a difference will be, with the object of most mass hitting the ground first.

Well stated, young man! We did our tests indoors of course. But yep, resistance from say, the wind, would perhaps change things. In a "perfect" test scenario though, without resistance, they will always be equal.

Gunny
09-01-2015, 12:00 PM
The only value that could change the speed at which both objects fall is air resistance, caused by the friction between the object and the air against its surface.

If there is no air in the room then they will fall at the same rate (mass by gravitational constant)
If there is air then the rate will change based on the thickness of the air, the thicker the air the greater of a difference will be, with the object of most mass hitting the ground first.

Want to try again? You're going about WWI.

jimnyc
09-01-2015, 12:05 PM
Want to try again? You're going about WWI.

I think he's right, no? He wasn't talking about dropping bombs, but answering my question about dropping marbles or other stupid crap!

Gunny
09-01-2015, 12:08 PM
I think he's right, no? He wasn't talking about dropping bombs, but answering my question about dropping marbles or other stupid crap!

I'll whoop your ass at marbles. That ain't even a close call Mr I was born after the Internet. :)

And I just pick on him cuz I can. ;)

jimnyc
09-01-2015, 12:11 PM
I'll whoop your ass at marbles. That ain't even a close call Mr I was born after the Internet. :)

And I just pick on him cuz I can. ;)

I don't think I ever played marbles? Only reason I ever had them was because of my wrist rocket slingshot! Getting hit by a marble from 20-25 yards will seriously hurt! :laugh:

Gunny
09-01-2015, 12:30 PM
I don't think I ever played marbles? Only reason I ever had them was because of my wrist rocket slingshot! Getting hit by a marble from 20-25 yards will seriously hurt! :laugh:

You never played marbles? Holy shit.

You're fired. :laugh:

And you're doubly fired for these Bee Gees song stuck in my head.

jimnyc
09-01-2015, 12:40 PM
You never played marbles? Holy shit.

You're fired. :laugh:

And you're doubly fired for these Bee Gees song stuck in my head.

I was too busy using them as weapons and lighting my army men on fire.

I'm lost on the Bee Gees thing. What song do you have in your head and why? And what the F did I do? :laugh: And how deep is your love?