Talk:E6B

Original Discussion

i just stumbled across this, uplifting story about this page: http://blog.wirelizard.ca/pivot/entry.php?id=43 —Preceding unsigned comment added by 82.143.235.237 (talk) 10:08, 5 November 2007 (UTC)

OK - my first original WikiPedia page, ever, after a couple of months of lurking, making anon minor edits, and wondering if I had something to add to the aviation sections. Editing/categorization/etc welcomed!

Should re-direction pages be set up for all the variant spellings of E6B? There does not appear to be ANY standard spelling, so I'm not sure how to approach this. --Madpilot 01:37, 13 Mar 2005 (UTC)

Thank you for setting up the original page. Never thought about doing one here before, but it's a perfect repository for info on it.

If possible, the page needs to be titled E-6B, which is its true name, along with the other variations as references. I've spent a huge sum of money and time tracking down its history, and will be updating the page with it soon. -- Kevindarling

The term "E6-B" is notthe true name of the device. Rather, it is merely one of many varying models of the device. Please see the detailed discussion on this, below.Clepsydrae (talk) 00:47, 23 February 2018 (UTC)

My first contribution to wikipedia, the front E6B pic -Dajackman

Hi - just a note, this is really hard to find, as the tittle "E6B" is the name given by the guys producing the thing. However, many different companys world wide produce it, and in the UK its known as th CRP-1, 1W, 3, 6 and 6M ... The correct name for it is a "Flight Computer" .. I've just started my own article as I figured that it didn't exsist on wiki as it doesn't come up in a search (bearing in mind I live in the UK and most GA pilots in the UK don't call it a E6B, but refer to it as a "crap1" .. May I suggest a title change to reflect its "generic name" and not one of the several manufactures name? (I suggest Flight Computer, not to be confused with an FMC) DreddHK 16:22, 21 June 2008 (UTC) —Preceding unsigned comment added by Dreddhk (talk • contribs)

I strongly concur. In fact, so does the Federal Aviation Administration (FAA), along with the United States Military, both of who refer to it in their various manuals as a "DR computer," "DR flight computer," or "flight computer." The most common reference is that of a "DR computer," in AFM 51-40, AFPAM 11-216, FAA-H-8083-25B, and FAA-H-8083-18. The first two are used for all pilots and navigators in the U.S. Air Force, and the second two are used by the FAA for all civilian pilots.

Reference above to the E-6B being called the Crap1 in the UK is true, but is only part of the story. The Crap1 is the version used by private pilots, but it is the Crap5 that is used by students for the Airline Transport Pilot Licence for their groundschool course. The Crap5 includes, for example, provision for Mach/TAS calculations which the private pilot would not need. The CRP designation as such seems to be the preserve of Pooleys, the main UK supplier of this type of instrument. Pooleys also supply a whole range of other variants, such as some with and some without 'wind arms' and also circular versions that do not use a drift slide.BroomstickPilot (talk) 10:21, 4 September 2010 (UTC)

When I first came into contact with the Dalton in the late 1950s (it was an ex RAF version in the form of a box with an endless belt inside,) I seem to remember the calculation side of the computer having a different name. If I recall correctly (it was after all fifty years ago) it was referred to as the Appleyard scale. However, nobody knew who Appleyard was. Can anybody please throw some light upon this?BroomstickPilot (talk) 10:32, 4 September 2010 (UTC)

The Jeppesen CR-1, while similar in function to the E-6B, is NOT the same thing. The CR-series lacks the movable slide and is just the circular portion. Here's a picture of the CR-3: [1] Captain Packrat (talk) 18:00, 9 April 2009 (UTC)

Math

I've just reformatted the provided equations so that they don't display as flat text anymore. Could the original author (if possible) or another Wikipedian familiar with the formula check my work and make sure I haven't made any glaring errors? --Yvh11a 13:44, 15 May 2006 (UTC)

I corrected the WCA equations. Groundspeed is weird, too. Please correct.

Ok, I corrected the GS equations, too. --64.254.245.130 19:27, 18 May 2006 (UTC)

I believe you need a negative sign before the WCA formula, and I think the GS formula should have a subtraction before the cosine term. I checked these using my real E-6B, and I think I'm right.

The last GS equation is indeed wrong. Sign error, is should read .... - 2 * B * D * .... instead.

For those interesting in the math: This comes directly out of the law of cosines. http://en.wikipedia.org/wiki/Law_of_cosines

--21:11, 28 August 2006 (UTC)Uffe

Also remember there are two ways of doing the Wind/Velocity math - either "wind up" or "wind down" .. each method works fine, but have slightly different ways of getting to the answer! DreddHK 17:00, 21 June 2008 (UTC) —Preceding unsigned comment added by Dreddhk (talk • contribs)

WCA and Ground Speed Math

Hi,

I'm sure that there should be a minus-sign in front of the sin-1 calculation. That would really calculate the WCA. The formula as it is stated right now calculates the Drift.

And I'm wondering about the GS calculation. I think it should read the formula mentioned in http://e6b.quickseek.com?

The current GS formula on this Wiki doesn't even come close to the right GS when using

Track=64 TAS=104 W/V=180/22

(should be about 112)

Regards! Arjan

• i concur with this. the equation, as listed now, does not give the wind correction angle. it should be sin(windDir - trueCourse), or same as what was mentioned above - a sign flip is necessary

Correction...

Correction on the things I say above: both formula's come up with about the same GS.

But when using "B sqrt(1-(D sin(A-C) / B)2) - D cos(A-C)" it comes up with 111,7471031 (=112)

When using the formula stated here, it comes up with 111,0764888 (=111)

Can anybody explain the differences between the two formulas? And which is the correct one? :-)

Regards! Arjan

Copyright?

Does anyone hold the copyright or patent for the E-6B style flight computer? (ie, a transparent rotating slider over concentric circles on one side with a logarithmic circular slide rule on the other) Sancho McCann 02:14, 23 December 2006 (UTC)

I see that the article answers my question!.... Good article! Sancho McCann 02:17, 23 December 2006 (UTC)

Conflict of interest

I just wanted to disclose that the link that I added a few months ago to the online e-6b applet was a link to my own website. I didn't realize at the time that this is not appropriate. So, I would like to open discussion as regards the appropriateness of this link. I believe it improves the article by allowing a reader to interact with a simulated E-6B. As regards the conflict of interest, it is not a monetary interest, as the website is a university website and the E-6B software is released under the GPL. Sancho 06:49, 11 April 2007 (UTC)

Your link is fine and appropriate to the article in my opinion and is not COI. But you may want to fix the link in the article so it does not lead to a redirect page. Russeasby 20:10, 13 April 2007 (UTC)

Okay, thanks! Sancho 07:49, 15 April 2007 (UTC)

MB-4A

The model given to USAF Navigators has MB-4A stamped on the top, contra this article.--72.191.31.112 (talk) 04:46, 10 January 2008 (UTC)

I am the person who wrote up the majority of the history. As noted in the article, a later designation starting in the early 1950s was MB-4. It, and CPU-26, have been used since then. - Kevin Darling (talk) 02:25, 13 May 2008 (UTC)

Both MB-4A and E-6B are merely the two most common examples of a DR computer, which is the device's proper name as evidenced by both FAA manuals as well as flight manuals from all military services.Clepsydrae (talk) 00:50, 23 February 2018 (UTC)

Derivation of mathematical solution

On November 12 I added an external link to my webpage showing the derivation to solution of the triangle of velocities, rather than just the equations. The link was removed as spam. I didn't realise external links were inappropriate. While my website is a commercial photography site the page the link pointed to, and all the other aviation related pages on the site, are all free with no commercial interest. I would like to open discussion as regards the appropriateness of this link. —Preceding unsigned comment added by 147.188.36.31 (talk) 09:16, 18 November 2008 (UTC)

Vector Addition of Velocities and Ground Speed

To obtain the ground speed vector one has to add the wind velocity vector to the air velocity vector. See the wind triangle diagram. The law of cosines can be used but care must be used to determine the relative angle between them. It is the supplementary angle of their difference. The direction of the air velocity vector is A - WCA and that of the the wind is C. Their difference is C - A + WCA. The supplement is 180° - C + A - WCA and the cosine of this is -cos(C - A + WCA). The ground speed is then,

$GS={\sqrt {B^{2}+D^{2}+2*B*D*\cos(C-A+WCA)}}$

Note the plus sign before cosine term. --Jbergquist (talk) 23:56, 7 November 2009 (UTC)

For completeness we could add a derivation for the WCA. Let a be the direction of motion relative to the air, d the desired course and w the direction the wind is moving. The corresponding speeds are,

$\left|{\vec {v}}_{a}\right|=V_{a}\quad \left|{\vec {v}}_{g}\right|=V_{g}\quad \left|{\vec {v}}_{w}\right|=V_{w}$

The WCA, Δa = d - a, is defined in terms of the motion through the air.

${\vec {v}}_{g}={\vec {v}}_{a}+{\vec {v}}_{w}$

${\vec {v}}_{g}\times {\vec {v}}_{g}=0={\vec {v}}_{a}\times {\vec {v}}_{g}+{\vec {v}}_{w}\times {\vec {v}}_{g}$

$0=V_{a}V_{g}\sin(a-d)+V_{w}V_{g}\sin(w-d)\$

So,

$V_{a}\sin(\Delta a)=V_{a}\sin(d-a)=V_{w}\sin(w-d)\$

And the forula for the WCA is,

$\Delta a=\sin ^{-1}\left({\frac {V_{w}\sin(w-d)}{V_{a}}}\right)$

In the same notation the ground speed is,

$V_{g}={\sqrt {V_{a}^{2}+V_{w}^{2}+2V_{a}V_{w}\cos(w-a)}}$

One doesn't need to know the desired course to compute the ground speed if the air speed and heading are known. --Jbergquist (talk) 06:58, 9 November 2009 (UTC)

In terms of geometry, the formula for the WCA results from the distances of the tips of both the ground speed vector and the wind speed vector from the line of the air speed vector being the same. It is the distance of a point from a line and not an application of the law of sines. When the wind speed vector is placed at the tip of the air speed vector its tip coincides with that of the ground speed vector and their components normal to the air speed vector also coincide. --Jbergquist (talk) 23:28, 11 November 2009 (UTC)

Construction and Durability

The article states a metal and plastic flight computer will wear out before an equivalent cardboard one. My experience says this to be false, having inherited several old metal flight computers, and a single paper one. The metal ones are all in good condition, and contrary to the article have gotten stiffer over the years rather than spinning freely as the plastic is worn. The paper one however has nearly disintegrated and is harder to read, enough to avoid carrying it on an actual flight. My primary flight computer is labeled Piper Flight Computer PC-3, those wishing to rename the article "Flight Computer" should take note, was my father's and was carried by him during over 7000 hours of long cross country flights and the associated planning, and it is so stiff I have to rub a bit of pencil graphite under the rotating portion so I can use it one-handed in the cockpit. Additionally, while the E6B moniker is used colloquially in the United States, I hear it used often by pilots in reference to the electronic flight computers as well, which are currently not covered here, so renaming the article Flight Computer and redirecting E6B and variant names seems like the best course of action. Davidlvann (talk) 23:41, 3 August 2010 (UTC)

I concur. There is indeed much NPOV commentary in the article, and some of it as you mentioned is incorrect. Thank you for information on the PC-3. I will try my best to include it in subsequent edits. I wonder how many manufacturers came up with their own DR computers and included them as aftermarket accessories? You're right, the metal (aluminum) ones stiffen up over time, I assume due to oxidation roughening the surfaces. I've tried graphite, silicone, and finally, a bit of polishing compound for the edges of the wind face. Dry silicone for the front and the polishing compound for the back (thoroughly cleaned, of course) seems to work best. I wouldn't dare use it on the front side as it would take the silkscreen off.Clepsydrae (talk) 02:01, 23 February 2018 (UTC)

My experience with my metal and cardboard E-6B's agrees with the article; My very first paper E-6B is still very usable and the wheels and slide still have some friction. My first aluminum one wasn't very well constructed to begin with (the A and B scales don't quite line up perfectly) and the slide falls out and the A-side wheel spins freely; no friction at all. In addition, the aluminum version is prone to scratching, denting and bending, where a cardboard one isn't.

I will agree with Davidlvann about the name. American pilots tend to refer to any flight computer as an E-6B, whether mechanical or digital. Some digital computers are even marketed as "electronic E-6B's." If the page gets renamed "Flight computer," other mechanical computers and digital computers also need mention. I personally feel that the E-6B-style computer is notable by itself to warrant it's own page. 65.191.125.142 (talk) 18:27, 24 January 2011 (UTC)

They will certainly receive mention, and thank you for that input. However, while the E-6B may get its own page, it's a DR computer, the same as the MB-4A, PC-3, and others mentioned here. Furthermore, the term DR computer includes both mechanical (circular slide rules) as well as electronic devices, so both sections will appear. While I understand how you personally feel, there's nothing notable about the E-6B that's not equally notable about the MB-4A and others as DR computers. The focus of the article will remain on the history and operation of a DR computer. Still needs a lot of work!Clepsydrae (talk) 02:01, 23 February 2018 (UTC)

• I use a CRP-5 model flight computer for example and we simply refer to it as the "computer". E6B may be notable enough to have its own article but definitely there must be an article for general flight computer term.--Abuk SABUK (talk) 20:02, 15 March 2012 (UTC)

Discussion Regarding using the device's proper name, "Dead Reckoning Computer" as the proper title for this Wikipedia Article

I have seen many incorrectly titled Wikipedia articles, and this article is a prime example of what no other encyclopedia would ever allow, for many reasons:

• The principle reason: The terms "E6B" and "E6-B" are not the name of the device, which is properly called a "dead reckoning computer." Rather, E6-B is merely one of many types of dead reckoning computers, specifically, the ones used by Army Air Forces. The Air Force type designation is "MB-4." Some civilian models, such as the ones from ASA, are labeled, "E6-B" or "E6-B2." Other civilian models use different nomenclature.
• The most common device over the last 30 years, issued by the military and used by pilots and navigators from all branches of the military, is labeled on the surface of its face as, "COMPUTER, AIR NAVIGATION, DEAD RECKONING, TYPE MB-4A."
• Both the Air Force Air Navigation Manual (AFM 51-40) from July 1973 as well as Flying Operations/Air Navigation (AFPAM 11-216, 1 March 2001) refer to the device as an "MB-4" or "MB-4A," "circular slide rule," "DR computer," or "dead reckoning computer."
• Both FAA-H-8083-25A, "Pilot's Handbook of Aeronautical Knowledge, 2008," FAA-H-8083-18, "Flight Navigator Handbook" and ICAO publications depict it as a "dead reckoning computer." This is most apparent in the captions and supporting text to figures 4-12 and 4-13 of FAA-H-8083-18.

Thus, the only term which is common to all military and civilian governing agencies worldwide, one which is neither a superset nor a subset of the actual device, is "dead reckoning computer."

Below we find a list of possible titles for this Wikipedia page:

• E6B, E6-B, E6-B2, and related: This is is merely one type of dead reckoning computer and by default, it excludes all other types in common use today. This is, therefore, a very poor choice for the title of this Wikipedia article. In fact, it is a subset of circular slide rules commonly referred to and labeled "dead reckoning computer."
• MB-4: Similar to "E6-B," it refers to one of the most common military types of dead reckoning computer. Thus, it is no more appropriate as the title of this article than EB6, as it, too, is a subset of dead reckoning computers.
• Flight computer: This is closer to the truth in that it's generic, inclusive of the many types of dead reckoning computers out there, and is indeed printed on the face of some civilian models. However, this term is not widely used in either flight training or flight operating manuals, and is rarely used in discussions. The other problem with using "flight computer" is that in the last 30 years, this term is more commonly applied to the computerized avionics built into the airplane itself, as well as many different handheld devices that are indeed flight computers but only some of which are electronic dead reckoning computers. Therefore, this choice would be inappropriate as it's a superset of the set of dead reckoning computers.
• Circular slide rule: While this is technically accurate, neither is it in common usage nor is it commonly used in either military or civilian technical manuals, ergo, it's another wrong choice for the title of this page.
• Whiz wheel: While this is what people call it more than anything else, by far, that's never been any sort of official title or name. Therefore, this, too is not an appropriate title for this article.
• DR computer: This is indeed a correct generic name for this device and is commonly used throughout the aviation community. However, it contains an acronym that's not self-explanatory and with which most people are unfamiliar.
• Dead reckoning computer: This is not only the correct generic and official name for this device, in wide use throughout both civilian and military aviation communities, but also as found in the leading piloting and navigator manuals printed by the Department of Defense, the Federal Aviation Administration and International Civil Aviation Organization (ICAO). This is also what's printed on the face of both military and and most civilian models/types. Googling "dead reckoning computer" and selecting "Images" provides a display of the widest range of these devices, and with many more pictures, than entering "E6B" or "E6-6."

Recommendations:

• Change the title of this article to: Dead reckoning computer
• Redirect all of the following to Dead reckoning computer:
  • E6B
  • E6-B
  • MB-4
  • MB-4A
  • DR computer
  • Whiz wheel
• Replace the "Flight computer" page with a disambiguation page for all types of flight computers, including both modern avionics, handheld computers, and the dead reckoning computer.
• Keep the "circular slide rule" section in the "slide rule" article, as it explains the advantages and disadvantages of both quite well.Clepsydrae (talk) 20:51, 26 January 2018 (UTC)

I found this page by searching for E6B, the only name I have heard anyone use for the device, regardless of what the official name is. Dead reckoning is only one of the calculations it assists with anyway. - NiD.29 (talk) 06:44, 22 January 2020 (UTC)

History of the E-6B

While some of the elements in this section are reasonably accurate, the section lacks proper citation and remains horrendously NPOV towards the name, "E-6B," to the point of being grossly inaccurate and in part, flat out fabricated out of thin air. As a "history," it fails, miserably. Clepsydrae (talk) 10:47, 20 February 2018 (UTC)

Gee, I didn't realize doing the right thing was subject to a popularity contest. You do realize the second "Oppose" actually and clearly stated the case FOR the move, don't you? Go back and re-read it again.Clepsydrae (talk) 04:46, 8 May 2018 (UTC)

Requested move 22 February 2018

The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section.

The result of the move request was: no consensus to move the page at this time, per the discussion below. Dekimasuよ! 01:35, 4 March 2018 (UTC)

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E6B → Dead reckoning computer – see talk discussions and recent moves in log. An editor has requested that the article be renamed. - Clepsydrae (talk) 02:04, 23 February 2018 (UTC) --Relisting.  samee  ^talk 06:22, 2 March 2018 (UTC)

Full details included in the proper name discussion. -- Clepsydrae (talk) 02:13, 23 February 2018 (UTC)

• Oppose – the article barely mentions the term "Dead reckoning computer". Personally, I think the current title is commonname, and the term "Dead reckoning computer" is perhaps too broad for the E6B-like slide rule devices. Dicklyon (talk) 05:56, 23 February 2018 (UTC)

Support - "Dead reckoning computer" is the logical title for title for the mechanical circular slide rule of which the Air Force's MB-4B, ASA's E6-B, Jeppesen's CR-2 and CSG-9, Pan American's Mark VIII-C, and many others are all various makes and models, just the same as "Train is the logical title for a vehicle with a tractor locomotive pulling cars on rails of which 4E5K, Little Joe, and BLS_Ae_6/8 are all various models. Contrary to the original and a couple of subsequent author's claims, "E6-B" is not the device's commonname. Rather, it is merely one of the more common models. By your logic, should we change the Cars section to Corolla and the Trucks to F-150? Of course not. That would be foolish. By the same token, the proper title of this article is "Dead reckoning computer," the same as Train and Airplane. As for "the article barely mentions" argument, that state only exists due to the overall improper titling in the first place. Properly, it's a "dead reckoning computer," which is both exactly and precisely (not "broad") what the "E6B-like side rule devices" actually are. Commonly, it's a "DR computer" or "whiz wheel." Titles of Wikipedia articles should be proper names, as with any encyclopedia, with redirects from various common names.Clepsydrae (talk) 06:12, 26 February 2018 (UTC)

• Oppose – other dead reckoning computers exist so to name just one of them with a generic description is probably misleading particularly if the user is searching for other models of computer. MilborneOne (talk) 15:47, 3 March 2018 (UTC)

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The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.