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Messages - Zaphod

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Flat Earth General / Re: Why do airplanes fly at the height they fly at?
« on: January 24, 2021, 04:20:25 AM »

In aviation there are strict definitions for the terms "height", "altitude", and "pressure altitude" (referenced to "standard" 1013.2 hpa). Do a bit of googling!! A pressure change of 1 hpa (mb) equates to approx 30ft. Also google "altimeter temperature errors" and "international standard atmosphere (isa)". If the air beneath the aircraft is colder than standard, the aircraft will be lower than indicated (and vice versa). A barometric altimeter is effectively measuring the weight of air beneath the aircraft to derive a reading.

As I'm sure Gonzo will confirm, on really really cold days aircraft on approach will be vectored in at higher platform altitudes to maintain ground and obstacle clearance. Altimeter error is approx 4% for every 10 degrees above or below isa. If it's cold, the air beneath the aircraft is denser. If flying a non-precision approach (more google research for you) on cold days we make corrections to the final approach altitude profile to adjust for this error.

Barometric altimeters are very accurate, you just have to know what they are measuring!


I guess we've spoken to each other many times!!

Flat Earth General / Re: Why do airplanes fly at the height they fly at?
« on: January 20, 2021, 05:32:42 AM »
The more speed the higher. Because the underneath air hit the plane's body upwards. The more speed, the bigger such air mass will hit the plane upwards.

This is Downwards Universal Deceleration mechanism. (Kind of UA)

As usual Danang, you're talking complete bollocks.

Flat Earth General / Re: Why do airplanes fly at the height they fly at?
« on: January 19, 2021, 11:50:43 AM »
Hi folks,

Air traffic controller here.

Aircraft (well, their operators mainly) want to fly at the most efficient altitude. For modern high-bypass turbofan engined-airliners, that’s usually 30k to 40k feet. It will depend on weight, so a fully loaded 777 at max take off weight flying for 15hrs might only be able to initially climb to, say, 32k ft but a few hours later can then climb again to 34 or 36k ft.

We all still use the humble altimeter to determine what we call level (‘level’ in altimetery being a generic term, ‘altitude’, ‘flight level’ and ‘height’ all have specific meaning). So the altimeter is really just a barometer with the needle reading off feet, rather than hectopascals or inches of Mercury. The flight crew will set the altimeter with a pressure datum against which the altimeter will compare outside air pressure.

If the altimeter is set to what’s called QFE, the altimeter will read 0ft if the aircraft is on the ground, and if in the air will give the HEIGHT above ground level where the QFE reading was taken.

If the altimeter is set to QNH, the altimeter will read 0ft at mean sea level, and if in the air will give ALTITUDE above sea level.

So if a aircraft took off from, say, Miami airport at sea level, the QNH and QFE are the same, so would both read 0ft on an altimeter. Arriving at Denver airport, let’s say 5000ft above sea level, an aircraft has a HEIGHT of 0ft, but an ALTITUDE of 5000ft.

Now, as mentioned above in the thread, air pressure varies as one flies through the air, and over time even if one stays in the same location.....each nation will promulgate what’s called a ‘Transition Altitude’, below which aircraft fly on QNH or QFE. Above this Transition Altitude, they all set their altimeters to an arbitrary setting of 1013.2hPa (29.92in). This ensures that all aircraft are working off the same datum. This pressure setting gives us ‘flight level’, which you might have heard referenced by flight crew over the PA on a flight.

Flight Level 320 is nominally 32k ft, if the pressure at sea level is 1013.2hPa. It could actually be 30k ft, or even 33k ft depending on actual air pressure. So even though the in flight map displayed to the passenger keeps saying a constant 32k ft, an aircraft could go from 31k to 33k ft above seal level over the course of a few hours as the air pressure changes.

GNSS-derived altitude is not used at higher levels, but is becoming more common in encoding flight paths nearer airports.

Radar altimeters only work for measuring heights of 2500ft or less.

Good stuff Gonzo, saved me some typing. My first visit here for some time.

Where do you work? I'm a 777 "driver". Not working much these days for obvious reasons.

TA at most major UK airports is 6000 ft but there is a move to make it 18K like the US. Low TAs can add to the workload on approach as it generally coincides with a Localiser and GP capture at circa China and Russia when you add in a combination of QFE and metric ops, after a long night flight, in can be a complete brainf@£k!!

I think people are getting a bit bogged down here.....

Forces are vector quantities, they have magnitudes and (importantly) directions. "Push" and "Pull" are surely just defining the direction of an applied force from the perspective of the person applying said force.

Take 2 people either side of a "regular" door.  One person will have to "push" to open it, the other will have to "pull". It's just grammatical convention. The door doesn't care what word you use, it just "feels" a force acting in one direction.

Take 2 people facing each other in a tug-of-war with a rope. They would both say they are "pulling" on the rope. If they both turned around (backs to each other) they might say they are both "pushing" the rope away. Either the way the rope experiences a stretching force and is placed under tension. As an aside, if they both  "pulled" a 100N force onto the rope, they would both have to "push" 100N of force into the ground to stay still, and a spring balance placed into the middle of the rope would read........100N! (not 200N as sandokhan thinks - something he could easily prove to himself by experiment, yet chooses not to!).

5 be pedantic, what I was taught, and I think it still holds good is that surface tension arises from the fact that water molecules have covalent bonds where they do that groovy electron sharing thing, which gives rise to the H end of the molecule being slightly +ve and the O end being ever so slightly -ve, resulting in the hydrogen bonding you mentioned .The molecules naturally joint together like tiny surface tension. And you are most correct about the amazing properties water has as a result, making it quite unique. By rights it should actually be a gas at room temperature, but luckily for us it ain’t!.

Ah yes, that sounds familiar. I had to answer a short essay question in my "O" Level chemistry exam on hydrogen bonding and now, nearly 40 years later, terms like "polar covalent bond" and "electronegativity" are surfacing in my head again! From what I remember not all covalent bonds will produce strong polarity, but in the case of water it does due to the relative sizes of the hydrogen and oxygen atoms. Might go and re-visit some of this with a beer later.



Try basic science and find out what a covalent bond actually is. That should sort you out.

Covalent bonds are responsible for the formation of the water molecule itself, not for the inter-molecular attraction that causes the surface tension of liquid water, which is hydrogen bonding in this case. A hydrogen bond is the attraction between the negatively charged oxygen atom of one molecule with the positively charged hydrogen atom of another.

Hydrogen bonds are really cool and are the reason why water is one of the very few substances that is less dense in solid form that its liquid state. That's the reason water ice floats, why oceans freeze from the top rather than the bottom.

Good vid on surface tension here....

Technology, Science & Alt Science / Re: GOD-TIER CAMERA LIST
« on: December 06, 2019, 09:07:35 AM »
You can't just talk about awesome old cameras?
Always has to be some dig at FE?

Actually, good point. Sorry.

My other "go to" camera is an old Panasonic TZ60 which I pretty much use in auto mode. Takes amazing pics and generally gets the right modes.

The 7D is lovely though. Feels really substantial. I treated myself to a 70-200 F2.8L many years ago and that's a joy to use. Fantastic colours.

Technology, Science & Alt Science / Re: GOD-TIER CAMERA LIST
« on: December 04, 2019, 09:48:06 AM »
My Canon 7d Mk1 is fab. 7FPS is brilliant for ski photos.

But, surely the Nikon P900 is the only camera that can show the earth is flat?

Flat Earth General / Re: Strongest FE Evidence
« on: December 04, 2019, 08:37:26 AM »

Boeing and Airbus and Rolls-Royce and everyone else BUILD THEIR ENGINES using the SCHAUBERGER MODEL/TEMPLATE.

No one else could make it work.

But he could, for the first time, using DOUBLE TORSION ETHER WAVES. That is why jet airplanes use much less fuel than we are told.

That's pure comedy gold Sandy.

I know I've only been flying large commercial jets for 30 years now, but you'd think I'd have heard of that. I mean, when I order the fuel to go to say, off the top of my head , Toronto, then sign for it so the fuelling company get paid, then do the calculations to ensure that we've got enough and there hasn't been an embarrasing pounds/kilos mix up etc and that we've got the correct total aircraft weight so we can work out the take-off performance and calculate the correct engine'd think somewhere along the line the whole "weights and measures" system would pick up on the fact that airliners burn less fuel than advertised.

And FFS jet engines simply use the same "suck-squeeze-bang-blow" as internal combustion engines, not di-lithium crystal fucking flux capacitors.

You really need to get out more. Maybe actually like go to Niagara-on-the-Lake and look at the top half of the Toronto skyline across the water. Or go to a beach where there are cliffs behind and and see how much farther you can see as you climb.

Flat Earth General / Re: Strongest FE Evidence
« on: December 02, 2019, 12:07:29 PM »

From an elevation of 170m, what do you think the distance to the horizon should be on a round Earth?

What do you think the distance from Grimsby ON to the base of the CN Tower is?

Flat Earth Debate / Re: Proof the Earth is round
« on: May 23, 2019, 12:23:07 AM »
You clearly didn't read what i put.

I bloody well did because you said..

i would even accept a sun over London

You're really going to have to be more thorough with your arguments if you want FEs to respond to you here.

For the avoidance of doubt, I don't believe the earth to be flat anymore than I believe that you have more than half a brain.

Flat Earth Debate / Re: Proof the Earth is round
« on: May 22, 2019, 10:48:20 PM »

I will say this again: Prove the Earth is flat, by taking a picture of the sun from NY, while it is over London. So far, I'm getting alot of "Well your arguments weak.

So if the sun is "over London" it must be 12 noon, which would make it 7am in New York, which is well past sunrise in the summer.

Your argument is definitely weak!

You haven't really thought this through have you?

Philosophy, Religion & Society / Re: Brexit
« on: May 16, 2019, 03:16:25 AM »
The quite brilliant Stewart Lee on Brexit....

Feynman Lost Lecture

This is a really good short video on elliptical orbits based on a lecture by the great Richard Feynman, who was teaching Newtonian mechanics.

Flat Earth General / Re: McCarthyism vs Global Earth Denialism
« on: March 18, 2019, 12:00:58 AM »
Michael Shermer's "Baloney Detection Kit". Should be required reading for ALL.

1. How reliable is the source of the claim?
2. Does the source make similar claims?
3. Have the claims been verified by somebody else?
4. Does this fit with the way the world works?
5. Has anyone tried to disprove the claim?
6. Where does the preponderance of evidence point?
7. Is the claimant playing by the rules of science?
8. Is the claimant providing positive evidence?
9. Does the new theory account for as many phenomena as the old theory?
10. Are personal beliefs driving the claim?

Stumbled across this earlier whilst putting off cleaning the chickens out!

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Flat Earth General / Re: Bob Knodel and the laser ring gyroscope
« on: March 14, 2019, 01:24:42 AM »
I have one in the "planning stage" entitled "On the Coriolis Acceleration and the Sagnac Delay".
The first post is intended to be just the definitions and simple derivations, then wait and see.

Good man, I'll leave it to you then. Maybe 2 seperate threads for the coriolis and sagnac effects?

Flat Earth General / Re: Bob Knodel and the laser ring gyroscope
« on: March 13, 2019, 10:25:28 AM »
It was going so well up until the last post Sandy.

No formulas here please! Start a new thread for that.

What I will say though is this. You appear to have it all arse-about-face...

The coriolis effect is what we see in the real world - objects moving in curved paths, different directions in different hemispheres. This is all explained nicely using a rotating globe. Moreover the formula for the coriolis effect (by which I mean a predicting tool for the paths of moving objects) is derived using relatively trivial geometry. We start with a model, derive a formula, test it against reality. The coriolis effect has absolutely nothing to do with laser gyros or the sagnac effect.

You're fond of quoting Feynman here - if the experiments don't match the hypothesis then the hypothesis is wrong.

Now, you say the observed coriolis effect has an all-together different cause. Your hypothesis has to explain all the observed effects. Your hypothesis should have a mechanism from which you can derive a formula that can be tested against reality.

So, in simply terms, can you explain how ether drift moves objects on a round or flat earth, and how they curve in different directions on either side of the equator?


I'm awkwardly aware that I'm deviating from the topic of Bob Knodel and laser gyros here. After dinner I might start a new thread

Flat Earth General / Re: Bob Knodel and the laser ring gyroscope
« on: March 13, 2019, 08:56:55 AM »
Sorry Sando, but I don't "get" your statement ...

"Laser gyros employ the CORIOLIS EFFECT formula for a SAGNAC interferometer"

For RLG, we are talking about the timing of counter-propgating light beams around a loop in the housing. If the gyro is rotating the 2 beams take different times to return to the origin producing a phase shift, which can then be used to derive the rotation rate. This is the sagnac effect. As I understand it this is how a laser gyro works. It's not the coriolis effect. TBH it doesn't really matter what you call it - laser gyros can measure rotation. End of.

The coriolis effect is describing the paths objects take on the earth. Mainstream science explains this with a rotating earth. You're saying the cause is a rotating ether instead.

Can you please give a summary, in your own words, of the ether drift experiment and how it moves physical objects? (maybe best in another thread).

But thanks, at least, for replying without a load of copy and paste. Much easier to follow.

Sorry, crossed with EMS. He asks a good question - answer that one first!

Flat Earth General / Re: Bob Knodel and the laser ring gyroscope
« on: March 13, 2019, 06:49:54 AM »

Can we please do the "nitty gritty" of the Sagnac and Coriolis effects in a separate thread. There's no need for formulas and derivations here.

As I understand it......

Bob Knodel use a laser gyro for his test. Laser gyros employ the sagnac effect to detect rotation of the gyro. The gyro was in a fixed position wrt to the earth. The test detected a rotation.

The coriolis effect is due to viewing things from a rotating reference frame. In our case both the earth and the viewer are rotating. It is the rotating earth that is the cause of the observed coriolis effect. It affects all things in that frame, not just light. Some people, despite evidence,  still believe light travels through an ether. If the coriolis effect was due to a rotating ether wouldn't it only affect light? On the contrary we see the coriolis effect with bullets, artillery shells, storms etc etc. If the earth was stationary, a real force would have to be applied to objects with mass for them to describe the observed curved paths. How does the ether apply this force?

There you go - no formulas!

Flat Earth General / Re: Bob Knodel and the laser ring gyroscope
« on: March 12, 2019, 11:19:50 PM »
Can you PLEASE start a separate thread for the Sagnac merry-go-round! It's most frustrating to have multiple threads derailed by this.

Flat Earth General / Re: Bob Knodel and the laser ring gyroscope
« on: March 12, 2019, 12:03:18 AM »
Can you please have this discussion about the sagnac effect elsewhere? Not that it hasn't been done to death on multiple threads before!

Flat Earth General / Re: Bob Knodel and the laser ring gyroscope
« on: February 21, 2019, 03:49:51 AM »
Go on Sandy, have a go at answering JBs step-by-step derivation. As you’re so sure you’re right, it will be easy to show he’s a fool no?

Flat Earth General / Re: Apollo 16 floodlight failure?
« on: April 02, 2018, 04:58:58 AM »
Right, here goes....

Without trawling in depth through this whole thread, and I can only speak with authority about Europe and EASA rules but.....

The ZFT type rating sim course at an approved TRTO (type rating training organisation) culminates in an LST (Licence Skills Test) followed by a ZFT (zero flight time) base training sim detail - circuits and bumps replacing the need to do this in an empty but real aircraft. This gets the successful candidate the necessary paperwork to toddle off to their State's local license issuing authority and have said type rating formally added to their licence.

There then follows a period of Line Flying Under Supervision (LIFUS), the first few sectors of which must carried out with a LIFUS qualified TRE (type rating examiner). These are real commercial sectors with passengers on board. After those sectors the rest of the line flying course can be carried out by non-LIFUS trainers. The course culminates in a line check after which the now fully fledged skipper/co-pilot is out of the training system and on their own.

Now, in the old (pre-ZFT) days these first sectors would also have a 3rd pilot on board to help with the workload of the trainer, and to nip into the seat should the trainer become incapacitated. With the advent of ZFT this is now only necessary in certain circumstances depending on the previous experience of the candidate, and also depending on internal company guidelines.

So, Cahaya is quite correct in that the first time a candidate who has completed a ZFT type rating course, onto say a B777, actually lands a real B777 will be on a commercial flight with passengers. This is under the supervision of a LIFUS instructor. If the instructor were to become incapacitated there is no safety pilot, and the ZFT course allows the candidate to do it on their own - the sims are that good. Totallackey is also correct in saying that the first landing is under supervision. You're arguing about different things.

I did base training on real empty aircraft for the BAC1-11 and DC-10, and have done ZFT courses for the B737 and B777. I am currently a LIFUS qualified TRE on the B777, so I hope I know what I'm talking about.

Quite what this has to do with the Apollo program I'm not sure - the guys were all test pilots and quite used to flying real things for the first time......for real!


This is very silly when evolution is used as the reason. Evolution wanted the animal to reach the high food? Lol, how about no Scott. (This isn't directed at you shifter, just using your quote.)

Evolution wants nothing, evolution does not care, evolution has no will to survive or care for any other creatures survival. Evolution is simply a bag of raw ingredients being shook for a very long time hoping to make something usable.

This would go down to my thread a while back, of how evolution is a religion. It is simply switching one God for another...

Maybe the reason we are always having to add intelligence, desire, will, motivation to us and everything else being on Earth is because there was an intelligent designer.

BHS, - it's pretty clear from this post, and others from you in this thread, that you really don't understand much about evolution - what it is and how it works.

This is an excellent website that will walk you through the basics

I can also very highly recommend Dawkins' book "The Greatest Show on Earth - The Evidence for Evolution". If you PM me I can probably email you a copy!


I know some people are put off by Dawkins' "style", especially his rather strident approach during religious debates. But please trust me, this book is nothing like The God Delusion in its style. Dawkins is a wonderful science educator and The Greatest Show on Earth is beautifully written. Have a read of the amazon reviews from the link above and give it a go.

I've also just been having another "play" with the evolution website linked above. Again, really good.

Flat Earth Debate / Re: Emotion
« on: March 08, 2018, 06:37:19 AM »
Yep, question everything and don't just believe something that somebody tells you.

Well, that's all well and good but at the end of the day you have to ask yourself "where is the evidence leading me?"

Science is the application of rational thinking and the respect for evidence.

Michael Shermer (Skeptics Society) has taken an idea from Carl Sagan and formulated a "baloney detection kit" that goes like this....

1. How reliable is the source of the claim?
2. Does the source make similar claims?
3. Have the claims been verified by somebody else?
4. Does this fit with the way the world works?
5. Has anyone tried to disprove the claim?
6. Where does the preponderance of evidence point?
7. Is the claimant(s) playing by the rules of science?
8. Does verifiable evidence exist?
9. Are personal beliefs driving the claim?

Flat Earth General / Re: Kersti Kaljulaid and Brian Cox Similarity
« on: March 08, 2018, 06:25:27 AM »
May God damn that president son of whore bitch to infinitive.

.... yeah, where she can be made to preach from the pulpit for eternity about verbs to the gathered conjugation.

If someone from A TV calls me as a flat earth believer and asks me something like this, then I'm sure I can take his head off.

I think you've got the wrong end of the stick. It's a phone IN show not phone OUT show. He called them, not the other way around.

Would love to see you have a discussion with any of the presenters there - go on go on!

What is AXP?
Who is Matt Dillahunty?
Why are you sure he would not have been so patient?

AXP - Atheist Experience. Phone in discussion and website/blog based in Austin TX. Thought it was reasonably obvious from the title. Evidently my bad.

Matt Dillahunty - one of the presenters. Thought he was famous enough. My bad.

Patience - My opinion, probably my bad too - I'm married so am used to being wrong. ;D

This is the first time I've seen a discussion about FE on AXP. I'm sure Matt Dillahunty would not have been so patient!

Anyway, make a coffee and enjoy!

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