Navigators Dalton Computer.

[RogerRB]

I am currently researching and collecting information on the Dalton Computer for an article I'm writing for (hopefully) publishing in a magazine.
I'm aware that they were used extensively in WW2 in the Mosquito as a friend of mine was an ex-Mosquito Navigator; what other WW2 aircraft used them and has anyone a photo' of a Navigators table with a Dalton on it?

[Self loading bear]

Is this what you what you are looking for?


https://cimg2.ibsrv.net/gimg/pprune.org-vbulletin/455x355/00037e69_b042_4efc_aecb_e092cb7c7d57_78f35a4dc547416d924e1d7 e1483692fe1bd456b.jpeg

Stirling navigator (http://www.pegelsoft.nl/nav.htm)


https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/554x800/6e748f45_e122_4a86_9c4c_af005ac8239d_bc34720f2501abf9823e0d8 ad67807c527034542.jpeg

Wellington navigator (https://demons.swallowthesky.org/post/72991936122)


https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/1300x2000/12fd3fb3_eb6e_4934_949c_e06f4af121e2_1836f257c01bce8de6fabb4 4e872a2bb7dbddbde.jpeg
Lancaster navigator


https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/544x800/3851bc07_df06_4412_8be1_3f378db809f2_422da44e4d413f7190cfd9d 5478ac34d239b4d4e.jpeg

Armstrong Whitford Whitley navigator (https://ww2today.com/25th-july-1941-bomber-command-target-hanover?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+WorldWarIIToday+%28World+War+II+Today%2 A+%29)

[Bergerie1]

Dalton Computers and their derivatives were being used right into the 1970s on BOAC 707s and VC10s before INS took over.

[DaveReidUK]

That's why F/Os always walked with a limp. :O

[Herod]

Mine is about three feet from where I'm sitting. The slide has long gone, but the wheel still serves a purpose. OK, used on flight sim, but still used. Issued 1965 I think.

[ExSp33db1rd]

I have the "box like" one, with a roller blind instead of a plastic slide, as shown in the last but one photograph, ( Lancaster navigator) right here, along with the type issued to me by the RAF in 1955, i.e the "thin" one with the slide, that I have always known as the E6B. That I used on BOAC Stratocruisers, Britannias and early 707's. although in later years the Nav. dept. produced G/S and Drift Component tables for climb, cruise and descent recommended speeds, that were quicker and easier to use than fiddling around drawing on the front of the computer, tho' the reverse side was still necessary for speed/distance/time calculations. ( no electronic computers or iPhones in those days - can you imagine ? !!! )

I also have a small, i.e 2", copy of the reverse side bought as a key ring gimmick some 50 years ago, from a shop on Nathan Rd. Hong Kong, now glued to the inside of my wallet. Was using that at the supermarket checkout one day, and the young assistant said " Wot's that " A circular slide rule, I replied. " Wot's a slide rule ? " One could weep.

[Brookmans Park]

My Dalton my 4 (ex the ATC) is still in working order

[john_tullamarine]

The pix, above, date back to the original US invention by Philip Dalton in the early 1930s. Later innovations saw the introduction of a much more easily useable slide version. The CR dates back to Siegfried Knemeyer's dreieckrechner, also in the early 30s, but on the other side of the WW2 table.

Am I a dinosaur - I still use my Dalton slide computer regularly ? A lot quicker and easier than the CR for a lot of stuff. With the few which have compressibility corrections included, who needs a CR ? Having said that, I use both.

[Fareastdriver]

My father had a Dalton that was fully mechanical. The was a long metal bar that was mounted at the bottom and as you rotated the slide it swung to give you drift and moving it against the speed markings it gave you corrected speed.

Ir disappeared with another handle cranking example shortly before his death.

[Yellow Sun]

I still have my 1965 issue Dalton that has seen much use. By far the fastest way to do unit of measurement conversions. I also have (somewhere) a Meer’s slide that was used on the V-Force to ascertain the corrections for speed and heading changes during Astro. There was another Astro related slide as well, iirc used for more esoteric activities such as Polaris homings. In a later life a RN Observer on helicopters showed me a Dalton slide used to calculate the jump distance for active sonar searches.

It was a very versatile piece of kit.

YS

[Barksdale Boy]

YS

I think it was a Mears slide, pioneered by one Flt Lt Wally Mears.

[ICM]

In the Tac Support airdrop business in the late 60s, we also had a slide for the calculation of Calculated Air Release Points (CARP). I suspect I still have one somewhere.

[RogerRB]

Many thanks for your replies and photo's.
I have just been loaned a book printed in 1941 titled Air Navigation; there is a picture in chapter 2 of, and I quote, 'the Circular Slide Rule on the Navigation Computor, Mk 111'.
Having skimmed through the book I'm impressed by the level of knowledge the Navigators had to learn (+ remember!).
This is a photo I can use in my article, however, the photo's posted above; are they protected by copyright?

RogerRB

[Self loading bear]

The photos are indeed probably protected by rights.
I included the links so you can ask permission at the site concerned.

succes SLB

[RogerRB]

Thank you; I shall be very careful!!!!

[Pom Pax]

In the last picture the Armstrong Whitford Whitley Navigator (https://ww2today.com/25th-july-1941-bomber-command-target-hanover?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+WorldWarIIToday+%28World+War+II+Today%2 A+%29) on the chart between the Dalton Computer and the Straight Edge is a Dalton Protractor. This very useful tool is not an invention in the 30's by an Ivy League whizz kid but a true British piece of kit invented whilst still a Captain by Vice-Admiral Sir Henry Percy Douglas KCB CMG FRGS FRAS AICE (1 November 1876 – 4 November 1939) a British naval officer who specialised in surveying and was Hydrographer of the Navy.

[ICM]

My neighbour, who was also my instructor when I started flying on the C-141A, was much taken by my Douglas Protractor. So much so that, shortly after starting his South East Asia tour on the AC-130, I got a message asking that I send him one, which I did. I gathered that it was ideal for their nightly work out over the Trail.

And sure enough, I see from its well-used cardboard case that Rear-Admiral Douglas is credited with the design, something I doubt I ever paid any attention to till now! Well done, Sir - it was a super bit of kit.

[Less Hair]

On offer for 8,95 $.
https://www.starpath.com/catalog/accessories/1852.htm

[staircase]

My RAF computer looks the same as the normal issue model but the slide is only 19 cms., and the disc 9 cm diameter

Would that be of interest to you, or was the small version common?

[sycamore]

stairs, slimline model for FJ crews....!

[condor17]

RogerB et al , thank you for a fascinating history lesson . Explaining things I took for granted when struggling to learn the inticacies of Dalton and Douglas ...
Not the oldest here , but my 1972 issue Dalton and Douglas still [ in normal times ] being used on a weekly basis instructing new students .

rgds condor .

[Pontius Navigator]

In the last picture the Armstrong Whitford Whitley Navigator (https://ww2today.com/25th-july-1941-bomber-command-target-hanover?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+WorldWarIIToday+%28World+War+II+Today%2 A+%29) on the chart between the Dalton Computer and the Straight Edge is a Dalton Protractor. This very useful tool is not an invention in the 30's by an Ivy League whizz kid but a true British piece of kit invented whilst still a Captain by Vice-Admiral Sir Henry Percy Douglas KCB CMG FRGS FRAS AICE (1 November 1876 – 4 November 1939) a British naval officer who specialised in surveying and was Hydrographer of the Navy.
Douglas Protractor.

[sycamore]

For those who like to keep sharp,or just refresh their skills,if you are watchers on `ads-b`..pick an airliner,and `click``on it. the sidebar will come up with the aircraft`s performance,IAS /G /SPEED.HEIGHT .TEMPERATURE AND WIND,HDG/TRACK..put the numbers onto your `Confuser`,and see if you come up with `what the aircraft is doing, or work it all backwards....
not sure if it works on fltradar24....

[DaveReidUK]

For those who like to keep sharp,or just refresh their skills,if you are watchers on `ads-b`..pick an airliner,and `click``on it. the sidebar will come up with the aircraft`s performance,IAS /G /SPEED.HEIGHT .TEMPERATURE AND WIND,HDG/TRACK..put the numbers onto your `Confuser`,and see if you come up with `what the aircraft is doing, or work it all backwards....
not sure if it works on fltradar24....

What is a "watcher on 'ADS-B'" ?

[sycamore]

Voyeur,one who watches,in this case,`watching the aircraft on ADS-B,same as you `watch` on FR24.....
FULL TITLE `GLOBE.ADSBEXCHANGE.COM.

[ex82watcher]

d
https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/1280x720/img_20210412_141217_f6096892598701d152e1161a44778b4709b58dc0 .jpg
Thought I'd post this photo of my HARBEN COURSE AND DISTANCE CALCULATOR which I found in my shed this morning.Picked it up in a bric a brac shop a few years ago,never seen another.

[Pontius Navigator]

My RAF computer looks the same as the normal issue model but the slide is only 19 cms., and the disc 9 cm diameter

Would that be of interest to you, or was the small version common?
IIRC that was a Mk 5 and as said for fast jets. Over 40s tended to use the Mk 4.

[Fareastdriver]

My father joined the RAF as a Brat in 1927. Somehow he was elected for aircrew training in 1942 or thereabouts and was sent to the States, Pensacola to be exact, to be trained by the US Navy. He was taught to fly both planes and boats and also to dance which surprised my mother somewhat. In his possessions before he died were two Dalton type computers. One of these was mechanical. There was a long strip of metal with calibration marks that was pivoted at the top of the instrument. It had a groove in it so that a peg on the wheel would swing it from side to side dependent on what wind you were using. I tried this once and it would give you, with a fair amount of grunt an accurate drift/groundspeed product. The other was similar to the Dalton I was used to but was like a box with handles top and bottom that would motor the paper background to cater for for anything from PBY2s or B29s. Both disappeared in his last days, probably by a relative who has since died.

Has anybody seen any others like that?

[paulross]

Here are a couple of scans from AP1234 "Air Navigation Volume 1" Dated 1938/1939 and 1941if it helps:


https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/1131x1600/ap1234_v1_1938_e79af94fde214c4381f98a2eece3bd3dfdca7f9c.png
https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/1131x1600/ap1234_v1_1941_024645bbee96889096d56b82a47eb38825349109.png

[Fareastdriver]

IIRC the top is similar but there are no background rolling handles on that one. Tragically I think that they are lost. My sister in Florida has his WW II log books but no knowledge of equipment.