Jeff Bezos' secretive rocket company just revealed its plans to towerover SpaceX

William Mook wrote:

On Saturday, September 17, 2016 at 2:03:15 PM UTC+12, Fred J. McCall wrote:
William Mook wrote:

On Wednesday, September 14, 2016 at 10:14:45 PM UTC+12, Jeff Findley wrote:
In article ,
says...

Rob wrote:

wrote:

"The largest of the two new rockets, called the "New Glenn 3-stage," is an
enormous 23 feet in diameter (about half the length of a school bus), 313 feet
tall (close to the height of the Apollo moon rockets), and will spew out 3.85
million pounds of thrust ? about half as powerful as NASA's Saturn V launcher.

Size in feet and weight in pounds? Is it designed in the 19th century?


It's designed someplace that's actually capable of doing it. Real
aeronautical engineers work in feet, pounds, and Rankine.

LOL. I'll take working in SI units over imperial units any day.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.

SI Rules!


Then you should avoid airplanes entirely. Fuel is measured in pounds,
altitude is measured in feet, and distance is measured in nautical
miles. The only place that did it differently was the old Soviet
Bloc.


Outside the US SI units are generally used (kg, meters, kilometers)


Not for aviation. The INTERNATIONAL STANDARD is pounds, feet,
nautical miles.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson

On Sep/18/2016 at 6:16 PM, JF Mezei wrote :
On 2016-09-18 13:57, Fred J. McCall wrote:

Not for aviation. The INTERNATIONAL STANDARD is pounds, feet,
nautical miles.


And nautical mile is actually an SI measure (exactly 1852metres in the
currect definition, while originally was the distance for a second of
latitude. ( the km was originally defined as 1/10,000 the distance
between equator and the pole, now defined relative to speed of light, so
the nautical mile is also based on speed of light).

No the nautical mile is not an SI measure. Pretty much all are units
currently in use would be SI measures by that standard. The definition
of an inch in the US (the place still using inches) is 2.54 cm. The
definition of a pound-mass 0.45359237 kg. The pound-force is defined
as the gravitational force exerted on a mass of one pound-mass in one
standard gravity, which is 9.80665 m/s^2. Etc.


Alain Fournier

JF Mezei wrote:
Note: aircraft measure how full their tanks are by volume, not weight,

Maybe on some small or older aircraft, where you can also find car-style
fuel gauges that only indicate E-1/4-1/2-3/4-F indication.

On modern jetliners, the fuel gauges indicate weight of fuel.

William Mook wrote:

This is a preliminary estimate of stage weights - based on what has been publicly released

Stage Total------- Stage Wgt- Propellant
1------ 3,080,000.0 2,002,000.0 1,767,920.0
2------ 1,078,000.0 700,700.0 618,772.0
3------ 377,300.0 245,245.0 216,570.2
Payload 132,055.0 132,055.0


Just what "publicly released" numbers are you using to arrive at the
preceding? Please provide a cite.

Here's the acceleration with 7 engines on the first stage, 1 engine on the second stage, and 1 engine on the third stage, all at full blast (but recall they can be throttled back from 550,000 lbf to 20,000 lbf!)

G-start G-end
1.250 3.571
0.510 1.458
1.458 4.165

Here's the radial acceleration due to centripetal force of a rocket moving at the terminal velocities each is capable of;

Speed Loss Net--- Gee- Net
2.800 0.865 1.935 0.063 0.937
6.000 1.295 4.705 0.371 0.629
9.200 1.295 7.905 1.048 -0.048

So, the acceleration of the first stage starts at 1.25 gees straight up and ends up at 3.571 gees largely horizontal! Of course these can be throttled back to maintain a reasonable maximum - say 2.000 gees. At first stage burn out the ship is moving at 1.9 km/sec and centripetal acceleration is 0.63 gees and 0.937 gees is pulling back. The second stage starts out at 0.5 gees but rises to 1.458 gees at second stage burn out. At that time the ship is moving at 4.7 km/sec and centripetal acceleration reduces gee loading to 0.63 gees! Now, to counteract that gravity pull, the rocket is pointed up 25.5 degrees - as it continues to accelerate horizontally at altitude. The third stage fires horizontally, and if its not throttled back itends up at over four gees! However, throttling again saves the day, limiting the load to two gee.


It looks like you're saying that it doesn't make orbit without the
third stage. That's not right. The mission profile for this thing is
like the old Saturn V mission profile, where the third stage is in LEO
before it fires and is used for deep space missions.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson

JF Mezei wrote:

On 2016-09-18 13:57, Fred J. McCall wrote:

Not for aviation. The INTERNATIONAL STANDARD is pounds, feet,
nautical miles.


And nautical mile is actually an SI measure


Poppycock.


... (exactly 1852metres in the
currect definition, while originally was the distance for a second of
latitude. ( the km was originally defined as 1/10,000 the distance
between equator and the pole, now defined relative to speed of light, so
the nautical mile is also based on speed of light).

From:
http://www.bipm.org/en/measurement-u...ase-units.html


Read your own cite. Do you see 'nautical mile' as one of the seven
base SI units? No. So which POWERS of the base units can you
multiply together to get 'nautical miles'? By your reasoning above,
almost any unit is an 'SI unit' since you can convert from an SI unit.


With regards to air traffic control, the standard practice is for ATC to
be able to handle american pilots in english, feet, pounds etc. However,
local pilots are able to speak local language and use local units (such
as ordering fuel in litres instead of pounds). However, local pilots
needs to be able to speak eaglish and understand US units when they
travel abroad.


Silly notion. Again, STANDARD (as in International Standard) aviation
units are as I stated. I've never heard of anything other than GA
aircraft order fuel in VOLUME measures like litres. You care about
the WEIGHT of fuel because all your fuel consumption figures are by
weight.


Note: aircraft measure how full their tanks are by volume, not weight,
so easier to reconciliate fuel loaded in litres with what the aircraft
tank gauges show. But you still need to convert to a weight measurememnt
for aircraft performance and take-off limits purposes.


Who gives a **** what the guage measures? You better be thinking
about fuel in weight, because that's how you determine if the thing
stops and falls out of the sky or not.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn

On Monday, September 19, 2016 at 5:57:22 AM UTC+12, Fred J. McCall wrote:
William Mook wrote:

On Saturday, September 17, 2016 at 2:03:15 PM UTC+12, Fred J. McCall wrote:
William Mook wrote:

On Wednesday, September 14, 2016 at 10:14:45 PM UTC+12, Jeff Findley wrote:
In article ,
says...

Rob wrote:

wrote:

"The largest of the two new rockets, called the "New Glenn 3-stage," is an
enormous 23 feet in diameter (about half the length of a school bus), 313 feet
tall (close to the height of the Apollo moon rockets), and will spew out 3.85
million pounds of thrust ? about half as powerful as NASA's Saturn V launcher.

Size in feet and weight in pounds? Is it designed in the 19th century?


It's designed someplace that's actually capable of doing it. Real
aeronautical engineers work in feet, pounds, and Rankine.

LOL. I'll take working in SI units over imperial units any day.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.

SI Rules!


Then you should avoid airplanes entirely. Fuel is measured in pounds,
altitude is measured in feet, and distance is measured in nautical
miles. The only place that did it differently was the old Soviet
Bloc.


Outside the US SI units are generally used (kg, meters, kilometers)


Not for aviation. The INTERNATIONAL STANDARD is pounds, feet,
nautical miles.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson

http://aerosavvy.com/metric-imperial/

One of the challenges of international flying is handling different units of measure in different countries. In aviation, the battle between imperial and metric units continues

JF Mezei wrote:

On 2016-09-19 11:11, Fred J. McCall wrote:

multiply together to get 'nautical miles'? By your reasoning above,
almost any unit is an 'SI unit' since you can convert from an SI unit.

The nautical mile used to be defined as 1/60s of a degree of latitude.
( 90 * 60 nautical miles gave you distance from equator to a pole).

(I used to think it was longitude (circumference at equator = nm * 60 *
360 but apparently it never was).

However, its current official definition of a nautical mile is 1852
metres. 1852 is no longer a conversion factor it is the actual definition.

It may not be an SI unit, but its definition is fixed to one.


Still a conversion factor. And still not an SI unit.


Note that from a GPS point of view, distance is measured in radians
(angle) and then converted to human distances using the radius of the
earth (which depends oh which model you use eg WGS84 where
equatorial=6378.137km and polar=6356.752km for radius


Note that that's not at all how GPS distances are measured. GPS
positions are in meters from an ECEF reference point.


Not sure how pre-GPS rockets/satellites worked to express their position
above earth (and thus do the math).


Geodetic coordinates.



Who gives a **** what the guage measures? You better be thinking
about fuel in weight, because that's how you determine if the thing
stops and falls out of the sky or not.


If the plane measures how full its tanks are by having a scale under the
tank, then yeah, it measures weight. But if it measures by how high the
fuel gets in the tank, then it measures volume.


Wrong. If it measures how high the fuel gets in the tank it measures
DEPTH. This is then converted to 'volume' before it hits the gauge
based on the meter knowing the shape of the tank to get volume or to
pounds by knowing the volume and density between the sensor(s) in the
tank and the gauge.


And this is why when you get fuel by the pound, they also give you the
current density of fuel so you (or plane's computer) do the conversion
from volume to pounds to verify this is what you have in the tanks.


No, they give you the 'current density' as a measure of the quality of
the fuel and so they can correct to a 'standard temperature density'
for performance calculations.


Note: in the case of the Gimli glider, the fiuel gaues were inop, so the
pilots did math to calculate how many litres they needed, and could not
check that that quantity fulled the tanks to expected level.


Uh, they were only doing volume calculations because the fuel gauges
were INOP.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn

William Mook wrote:

On Monday, September 19, 2016 at 5:57:22 AM UTC+12, Fred J. McCall wrote:
William Mook wrote:

On Saturday, September 17, 2016 at 2:03:15 PM UTC+12, Fred J. McCall wrote:
William Mook wrote:

On Wednesday, September 14, 2016 at 10:14:45 PM UTC+12, Jeff Findley wrote:
In article ,
says...

Rob wrote:

wrote:

"The largest of the two new rockets, called the "New Glenn 3-stage," is an
enormous 23 feet in diameter (about half the length of a school bus), 313 feet
tall (close to the height of the Apollo moon rockets), and will spew out 3.85
million pounds of thrust ? about half as powerful as NASA's Saturn V launcher.

Size in feet and weight in pounds? Is it designed in the 19th century?


It's designed someplace that's actually capable of doing it. Real
aeronautical engineers work in feet, pounds, and Rankine.

LOL. I'll take working in SI units over imperial units any day.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.

SI Rules!


Then you should avoid airplanes entirely. Fuel is measured in pounds,
altitude is measured in feet, and distance is measured in nautical
miles. The only place that did it differently was the old Soviet
Bloc.


Outside the US SI units are generally used (kg, meters, kilometers)


Not for aviation. The INTERNATIONAL STANDARD is pounds, feet,
nautical miles.


http://aerosavvy.com/metric-imperial/

One of the challenges of international flying is handling different units of measure in different countries. In aviation, the battle between imperial and metric units continues


"International pilots are extremely well versed in all the aviation
units discussed in my article below. We use these units daily and can
juggle them in our sleep. The AirAsia 8501 flight crew was on their
own turf, flying a familiar route. To blindly speculate that they
became confused about units of measure is absurd."

Note that your cite agrees exactly with what I already said. Also
note that Russia (and the old Soviet Bloc), the big player using
metric (China and North Korea use metric because ... guess where they
got their aircraft from?) is channging to a flight level system based
on feet for altitude.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn

JF Mezei wrote:

On 2016-09-20 13:30, Fred J. McCall wrote:

Still a conversion factor. And still not an SI unit.

farenheight is defined by freezing and boiling points of water. You can
get a farenheit temperature wiothout needing to refer to another scale.

Nautical Mile is defined in terms of metres, a SI meaure. You cannot
get a nm without refering to the metre because it is defined as 1852 metres.


Still a conversion factor. And still not an SI unit.


Note that that's not at all how GPS distances are measured. GPS
positions are in meters from an ECEF reference point.

http://williams.best.vwh.net/avform.htm#Dist

latitude and longitudes are all about angles when you compare 2 locations.


No, they aren't.


(how the GPS calculates lat and lon from satellite signals propagation
delays and dopler is a different story)


GPS only bothers to calculate lat/lon/alt for the convenience of the
humans.


Wrong. If it measures how high the fuel gets in the tank it measures
DEPTH. This is then converted to 'volume' before it hits the gauge

At least you agree that plane's tank doesn't measure the weight of the fuel.


But the gauge very well may (actually mass, since an aircraft is an
accelerated frame).


No, they give you the 'current density' as a measure of the quality of
the fuel and so they can correct to a 'standard temperature density'
for performance calculations.

The thing is that truck that feed the fuel to the plane would measure it
in volume as it passes through the pump and gauge. So the density would
be entered at the truck to convert the volume to weight.


Fuel is priced in volume but jets buy it by weight.


When fuel is delivered in litres, then the conversion to weight is done
in the plans based on the density provided by the fueling crews.


No.


Uh, they were only doing volume calculations because the fuel gauges
were INOP.

The inop fuel gauges prevented them from verifying they had ordered
enough fuel and that enough fuel was loaded. The original mistake was in
their math in calculating how much fuel to order. The fueling folks put
into the plane the amount requested by pilots.

Had the fuel gauges worked, pilots would have realised that the amount
they ordered only half filled the tanks which should have been nearly
full and detected the original mistake.

Note: for water: 1litre = 1kg = 2.2 US pounds. Fuel is lighter than
water but not that much. So pilots should have had a rough sanity check
when they ordered their fuel or did the conversion from pounds to litres
that something was amiss.


The gauge in the aircraft would have shown POUNDS of fuel.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson

On Sep/20/2016 at 5:37 PM, Fred J. McCall wrote :
JF Mezei wrote:

On 2016-09-20 13:30, Fred J. McCall wrote:

Still a conversion factor. And still not an SI unit.

farenheight is defined by freezing and boiling points of water. You can
get a farenheit temperature wiothout needing to refer to another scale.

Nautical Mile is defined in terms of metres, a SI meaure. You cannot
get a nm without refering to the metre because it is defined as 1852 metres.


Still a conversion factor. And still not an SI unit.

No it isn't a conversion factor. It is the definition. Nautical miles,
inches, pounds etc. are defined based on SI units.


Alain Fournier