Some aircraft parts I picked up in Lincoln

[DogTailRed2]

Can anyone tell me what these gauges do, are for?
This one from a Victor.
https://live.staticflickr.com/65535/53109981712_372fde28da_b.jpg

This one from a Valiant.
https://live.staticflickr.com/65535/53111062283_0ac50844f6_b.jpg

I'll post more pics and the serials etc later.

[HOVIS]

Top one looks like a fuel gauge.

[NineEighteen]

And the second one says ‘DECCA’ which is a defunct radio navigation system. Vaguely recall it coming up in my ATPL theory.

0918

[Cornish Jack]

Manufacturer's name on the second pic gives the clue - Decca control box with 'chain' selection ... presumably, there would have been a set of three lane meters somewhere as part of the display ?

[DogTailRed2]

And the second one says ‘DECCA’ which is a defunct radio navigation system. Vaguely recall it coming up in my ATPL theory.

0918
I was wondering if CHAIN has anything to do with the Chain Home radar network?
BTW is DECCA the same DECCA as in the records?

[Uplinker]

I think I know the shop you went to. I looked in the window many years ago, but managed to stop myself going inside; knowing the damage that might do to my wallet !

[John Hill]

The DECCA system consisted of three slave transmitters arranged in a triangle with a master station in the middle, this ensemble was called a DECCA 'chain'.

[ShyTorque]

What a coincidence! I was dusting my bedroom shelf only ten minutes ago and the green Decometer I bought (sentimental reasons only) from RAF Puma XW222, which I used to fly many years ago.

My wife asked me about it and I briefly explained how we had to to use DECCA, which wasn’t really designed to be used at 140kts at low level. Far too slow and inaccurate to be of tactical use (a bit like me).

We had a procedure where our crewman could carry out a DECCA letdown as an airfield approach. Done properly, when atmospheric/magnetic errors weren’t messing things up, they were at least as accurate as some SRAs.

Thank goodness for GPS…. :cool:

[radeng]

I was wondering if CHAIN has anything to do with the Chain Home radar network?
BTW is DECCA the same DECCA as in the records?

Iit was the same Decca. They had a number of various specialist companies including a radar company, a communications company and MARNS (Mandatory Air Radio Navigation Systems) who amongst other things, manufactured NDBs. The Decca Navigator system was used for the D-day landings because of its accuracy, which I read was needed to get landing craft to the right spots where mines had been cleared. Post war, it was used in aircraft - there were various Decca chains ( a chain was three stations) throughout much of the world. It was used a lot by fishermen, with coverage up into the White Sea. Decca never sold the receivers but rented them out. When the patents ran out and other companies started providing cheap competition, Decca announced theyw ere shutting the Decca chain transmitters down: this caused such an uproar that the UK government paid Decca to run the chains for a year or two. They've all been gone for well over 25 years now.. Another Decca navigation system was HiFix, which got used in several parts of the world for accurate surveying for oil exploration in the days before GPS. Decca went bust, pulled down - I believe if my memory is correct., by losses on the recording side. Racal got the rest, but now they've gone and I think that whatever is still left is now Thales..

[Sallyann1234]

As radeng said. The last bits of Decca were taken over by Thales until they finally became obsolete.
Just another of the many great British radio/electronics companies that no longer exist, many killed by incompetent management.

[ShyTorque]

https://cimg4.ibsrv.net/gimg/pprune.org-vbulletin/2000x1504/img_0670_d9276a454164da559930c09be41ff6eda7e6da5a.jpeg

This still has its ‘Serviceable’ label. Removed from XW222 in 1995

[teeteringhead]

We had a procedure where our crewman could carry out a DECCA letdown as an airfield approach. And it always seemed to be down the Green G30 lane .......

Well, it did at ODIZ and ALDZ IIRC...............

[inbalance]

And the second one says ‘DECCA’ which is a defunct radio navigation system. Vaguely recall it coming up in my ATPL theory.

0918
There has been a modern unit called AP Navigator.
It worked like a modern GPS, but lagged a Database. So one had to use coordinates that could be stored in a 10 waypoint database.
I only recall one Cessna thatwas equipped with it.
That would have bern in the late 90s

DECCA was designed for maritime use.
Thats the reason the transmitter where located near the shorelines only and the range was limited.

[Asturias56]

"Another Decca navigation system was HiFix, which got used in several parts of the world for accurate surveying for oil exploration in the days before GPS. "

Ho Ho Ho "accurate" - well it was better than nothing but it often gave people a mistaken idea that they were in exactly the right place...........

[NutLoose]

Hey Shy, I have the end of a Puma collective floating around, I bought some ally tube to fit it to and hope eventually to get all the switches etc working for a PC flight sim.

[NutLoose]

What a coincidence! I was dusting my bedroom shelf only ten minutes ago and the green Decometer I bought (sentimental reasons only) from RAF Puma XW222, which I used to fly many years ago.

My wife asked me about it and I briefly explained how we had to to use DECCA, which wasn’t really designed to be used at 140kts at low level. Far too slow and inaccurate to be of tactical use (a bit like me).

We had a procedure where our crewman could carry out a DECCA letdown as an airfield approach. Done properly, when atmospheric/magnetic errors weren’t messing things up, they were at least as accurate as some SRAs.

Thank goodness for GPS…. :cool:


Here you go, have a matching PTR175…

https://www.ebay.co.uk/itm/133601613557?hash=item1f1b46d6f5:g:MOUAAOSwjN5f0LGL&amdata=enc%3AAQAIAAAAwMnslsUloRD%2F9DdR%2FGNRs0rIMT2W7nq1LBL TWwsEKmdAQgnmmel0ynkcNimAIzriUFiyX%2BUV0XicmvtvHtgFtsWfzyE7t phkA4cbtQevXbKiSKbFIkWrPPb2zBqE5uSxghjnNnBqv1oMaozC6HIT%2FLD SbutA8dKnjVzwUVWXFYWlTupyDE%2Ffg4%2BL6IlPHVLIyeZXzsUq2v8mhAT qOy8BiNEbNxPh2VMZvnOM5LIJdk6m3%2BtwcIDn2aD1gujG%2Bs8Iqg%3D%3 D%7Ctkp%3ABk9SR_KLxrW9Yg

[Sallyann1234]

DECCA was designed for maritime use.
Thats the reason the transmitter where located near the shorelines only and the range was limited.
That was HiFix.

[Cornish Jack]

When I started Whirlwind S&R, Decca was a standard fit. Used carefully, it was an excellent bit of kit and, as Shy pointed out, it could be set up for self-generated SRAs. Valley was particularly suited, as the main runway had a 'lane' line directly oriented , so the range countdown was simple on one of the other decometers. Thorney flight did three callouts on a really grotty day and all the nav was via Decca.
A secondary part of the system was Dectra - a 'moving map' display, coaming mounted, but limited uptake for civvy use only.

[ShyTorque]

RAF Pumas had the DECCA moving map system in the early days. To make it work, it used a bizarre, distorted map with a spring finger which just pointed to where the aircraft was. No doubt it would have been great on a ship.

DECCA TANS (Tactical Air Nav System) came next and used DECCA info to update its position. Just ten waypoints, in lat/long which were deleted from memory when the aircraft was next de-powered.

”Super TANS”, which was GPS based, replaced that.

[ShyTorque]

Nutty,

I thought about donating my Decometer to Newark Air Museum when I was informed that they had obtained a Puma. I went down to see it and realised it would be pointless in view of the fact that it didn’t even have an instrument panel! It’s little more than a bare shell.

[megan]

Another Decca navigation system was HiFix, which got used in several parts of the world for accurate surveyingSpent a few years in the hydrographic survey world radeng and part of my job was flying the HiFix stations ashore to be set up and dismantled at the end, put a receiver in the aircraft as well so could fly around coast lines and map those as well. Part of it was revising maps made by Captain Cook, amazing how accurate he was when you consider the technology he was working with.

[CISTRS]

Chain 5 indicates that the distance recorded is half a furlong from the reference point.
The length of 5 cricket pitches...
10 chains = one furlong.

I am told that this measurement of distance is not currently used for aviation.

[deeceethree]

I am told that this measurement of distance is not currently used for aviation.
Are you sure? I have this vague recollection that the altimeter subscale setting, on the widebody I flew, was marked in furlongs. Or was it the flap gauge? Hmmm, can't remember clearly ... must be getting old. Were the fuel gauges marked in volume of Olympic swimming pools? Gosh, the memories are all rather fuzzy now ...... 🤪

😂🤣

[CISTRS]

In my experience, the fuel gauges were marked in bushels (8 imperial gallons)

[Hydromet]

Spent a few years in the hydrographic survey world radeng and part of my job was flying the HiFix stations ashore to be set up and dismantled at the end, put a receiver in the aircraft as well so could fly around coast lines and map those as well. Part of it was revising maps made by Captain Cook, amazing how accurate he was when you consider the technology he was working with.
The best technology available at the time, in the hands of an expert.

[DuncanDoenitz]

In my experience, the fuel gauges were marked in bushels (8 imperial gallons)
Approximately equal to one firkin. Hence the "ZERO FIRKIN FUEL" warning flag on some 19th Century aircraft.

[ericferret]

In Germany the Scouts were in pounds, the Gazelles in kilograms and the bowsers delivered in gallons or litres.
What could possibly go wrong!

[ShyTorque]

Let’s not forget the AS355….fuel gauges marked in %. Obviously, you needed to know the percentage of what it meant.

I worked out that our base fuel pump delivered 1% every five seconds, or 12% every minute.

What could possibly go wrong? Thankfully, it never did, it worked a treat but obviously the fuel gauge was always checked afterwards.

[MENELAUS]

The best technology available at the time, in the hands of an expert.


Ah the joys of a survey flight.
Daily bread/ water/ fresh fruit / mail runs to the Decca engineers ashore so that they didn’t go short.
Setting up trisponder ( with the a/c as a slave station) ashore so that the Surveyors could “get control “ of the survey area. Usually involved dropping a couple of sailors off on a mountain somewhere with trisponder, cement mortar and white paint so that they could build a trig point.
And the joys of the ‘Canberra’ Williamson camera with the lens through a hole in the floor and the crewman hanging out the door trying to line up the grid lines.
When we had finished surverying the Jason’ Islands last surveyed several hundred years ago by, strangely enough, Lt Jason, they were found to be several hundred meters out. Not bad considering the kit they had !
All said and done, some of the best flying of my career.

[Saintsman]

May as well add LORAN to the mix https://en.wikipedia.org/wiki/LORAN

[radeng]

The first Decca chains were set up for D Day, and most of them were initially for maritime use. Rather more accurate than LORAN which was long range . Indeed, Sky wave synchronised Loran (SSLORAN) was used for bombers on raids to the Ploesti oilfields, but of course was only of use at night, because long range propagation around 2 MHz generally doesn't exist during daylight hours. I hear that ELORAN (extended LORAN) in the 100kHz region is making a comeback because it's much harder to spoof than GPS. Where Decca Navigator really took off was with the deep sea fishing fleet (anybody remember back when we had one?). after WW2., when trawlers were getting bigger and going further up ito the White Sea. That was also when the Merchant Fishing Vessels Radio Rules.came about, because greater ranges were needed than could be obtained on 2 MHz.

[DogTailRed2]

Thank you for the replies. All very interesting.
Is there any way to determine that said part came from said aircraft? At all possible to determine if it actually came from an aircraft and not a spare, off a boat etc?
I have a Vulcan fuel gauge. It has `bay` written on it so I assume it was used in the servicing bay for calibration and not necessarily from an actual aircraft?

[NRU74]

I was on Valiants but I don't recall any Decca kit on the aircraft.

[DogTailRed2]

I was on Valiants but I don't recall any Decca kit on the aircraft.
Thanks. I guess that begs the question any ideas which aircraft it might have come off?

[Kraftstoffvondesibel]

I was wondering if CHAIN has anything to do with the Chain Home radar network?
BTW is DECCA the same DECCA as in the records?

A spin off of Decca records indeed. Decca records did lots of pioneering tech work. Stereo was a parallell development and had things in common with the development of radar and electronic navigation. Decca were big on stereo development.

[DuncanDoenitz]

A spin off of Decca records indeed. Decca records did lots of pioneering tech work. Stereo was a parallell development and had things in common with the development of radar and electronic navigation. Decca were big on stereo development.

And the Phantom FGR2's reconnaissance pod was by EMI.

[Ninthace]

I learned to use Decca at Dartmouth but the only time I got to use radio aids to navigate, there was no Decca chain in the part of the world we were in and I had not done the course on LORAN so I was not a lot of help once the hard part of the world slipped off the radar. The best advice I could give was “steady as she goes, Hong Kong is roughly two days in the direction we are currently pointing.” Fortunately, they were not relying on me. Never understood how those Air Force Johnnies got to unfurl the chart in that tiny little cockpit, let alone draw lines on it.

[Jhieminga]

I think I know the shop you went to. I looked in the window many years ago, but managed to stop myself going inside; knowing the damage that might do to my wallet !
Just curious but which shop are we talking about? I just spent a few days near Lincoln and may have missed a major attraction… although me credit card may hold a different opinion of course.

[megan]

In Germany the Scouts were in pounds, the Gazelles in kilograms and the bowsers delivered in gallons or litres.
What could possibly go wrong!Google "Gimli Glider", a 767 that befell your proposition and made a dead stick landing.

[visibility3miles]

Are you sure? I have this vague recollection that the altimeter subscale setting, on the widebody I flew, was marked in furlongs. Or was it the flap gauge? Hmmm, can't remember clearly ... must be getting old. Were the fuel gauges marked in volume of Olympic swimming pools? Gosh, the memories are all rather fuzzy now ...... 🤪

😂🤣

I’m glad that The United States was one of the original countries to sign the Treaty of the Meter (https://en.wikipedia.org/wiki/Metre_Convention) in 1875,

We must be on the metric sytsem. Right? Give me an inch and I’ll bet you a mile that we are!

https://www.nist.gov/blogs/taking-measure/busting-myths-about-metric-system

[BEagle]

Here you go, have a matching PTR175…

Actually it's rather more than a PTR175 - it's a PTR1751WWH which includes the frequency hopping HaveQuick system. Useless without the control panel though.

[DogTailRed2]

Just curious but which shop are we talking about? I just spent a few days near Lincoln and may have missed a major attraction… although me credit card may hold a different opinion of course.
As you go up the hill on the right. I forget what it's called but has a window festooned with aircraft parts among other things.

[ShyTorque]

Actually it's rather more than a PTR175 - it's a PTR1751WWH which includes the frequency hopping HaveQuick system. Useless without the control panel though.

I wouldn’t give it house room. No point in having u/s electronics sitting on your bedroom shelf ;).

[BEagle]

J. Birkett owned the shop but sadly passed away last year at the age of 93.

I do not know whether the shop is still open.

[DogTailRed2]

J. Birkett owned the shop but sadly passed away last year at the age of 93.

I do not know whether the shop is still open.
Still open.

[Asturias56]

I wouldn’t give it house room. No point in having u/s electronics sitting on your bedroom shelf ;).


that's what shelves are for , shirley?

[NutLoose]

Nutty,

I thought about donating my Decometer to Newark Air Museum when I was informed that they had obtained a Puma. I went down to see it and realised it would be pointless in view of the fact that it didn’t even have an instrument panel! It’s little more than a bare shell.

Shy, It has come on leaps and bounds and the cockpit is now complete, they have a spare fuselage as well. judging by the boxes they may have rotor blades, they even have authentic bodge tape on the nose panel :p

You can see it here and watch the film, it will eventually have someone who flew them doing a cockpit walk around.

https://www.youtube.com/watch?v=_E0gjghAoog

https://live.staticflickr.com/65535/52465163752_83f76bc1e2_c.jpg
https://live.staticflickr.com/65535/52465952474_81147bcfc5_c.jpg

https://www.flickr.com/photos/53922167@N05/]Martin Laycock

[Herod]

In Germany the Scouts were in pounds, the Gazelles in kilograms and the bowsers delivered in gallons or litres.
What could possibly go wrong!

Try this. Fuel planning was in kg, fuel delivered in litres, main tank gauges in Imp gallons, aux tank gauges in US gallons. In the days before electronic calculators !!

[ShyTorque]

You can see it here and watch the film, it will eventually have someone who flew them doing a cockpit walk around.

I last flew XW208 in March 1991, in NI. With the infamous “Air Jair” Smith. I’m not qualified to do a walk round video with only three tours and two and a half thousand hours on type. My Decometer wouldn’t fit that airframe as it had been upgraded with SuperTans.

But maybe I’ll visit it for old times sake.

[radar101]

Just curious but which shop are we talking about? I just spent a few days near Lincoln and may have missed a major attraction… although me credit card may hold a different opinion of course.

At the bottom of Steep Hill

[NutLoose]

Thank you for the replies. All very interesting.
Is there any way to determine that said part came from said aircraft? At all possible to determine if it actually came from an aircraft and not a spare, off a boat etc?
I have a Vulcan fuel gauge. It has `bay` written on it so I assume it was used in the servicing bay for calibration and not necessarily from an actual aircraft?

The part number will help,as an example Puma helicopter parts tended to start with 526 MM and Wessex helicopters 28 WX

check these lists

https://www.key.aero/forum/historic-aviation/62089-aircraft-part-numbers

[ItsonlyMeagain]

First flew 222 Nov 82 and last Jan 92.

It now resides in the superb Ulster Aviation Society collection at Maze, Long Kesh where I am a tour guide.

It is pretty well complete, just missing a PTR 175 and a decometer……

Me

[DogTailRed2]

The details on the back of the gauge are;
SMITHS: FUEL CONTENTS GAUGE
CODE: LK 86
SER NO. B1 -26804
MOD NO. 01 02
and a sticker on the side with 6A 6629 written on it
The rear has 12 screws, several with a wire cut off and marked a-p.

The details for the nav box are;
MK 8A RX CONTROL PANEL
TYPE 918 SER NO 285 WR 630
DECCA NAVIGATOR CO LTD
MADE IN ENGLAND

HAND WRITTEN ON THE DEVICE 5826 99-945-0478
The reverse has what appears to be an RS232 connector of some sort.

btw are these things safe to open. Any nasties like radium, asbestos? I'm keen to see if I can get the nav box lamps to work for a model I'm building.

Any confirmation what aircraft these bits came from would be interesting.

[happybiker]

The Decca Mk 8A was an airborne receiver unit and the control unit was Type 918. The Mk 8 and 8A were fitted to both civil and military aircraft. I was at RRE Pershore 1966 to 1970 and worked with Decca Navigator Type 990 known in the RAF as the Mk 1(Air) which was I understand based on the Mk 9 system with enhancements. It was installed on a number of Canberras and the Varsity aircraft operated by the RRE. When I left in 1970 we had installed a couple of Decca Mk 15 systems on Canberras.

As I recall there are no "nasties" inside to be aware of if you want to open them up. Typical of the time you will will find capacitors, resistors lots of relays, valves, crystals and maybe the odd transistor. The following link to a historical Decca site may be of interest as it refers to some of the aircraft types that used Decca Navigator.

Decca Navigator - Airborne Receivers and Indicators (jproc.ca) (http://www.jproc.ca/hyperbolic/decca_rx_ind_airborne.html)

[DogTailRed2]

That's very interesting thanks. So the Mk8 was fitted to some Valiants. Unlikely mine was but it's representative so will go nicely with my model.

[Self loading bear]

Birkett (https://maps.app.goo.gl/PTwGjuWCovwGXH8d7?g_st=ic)

[ShyTorque]

First flew 222 Nov 82 and last Jan 92.

It now resides in the superb Ulster Aviation Society collection at Maze, Long Kesh where I am a tour guide.

It is pretty well complete, just missing a PTR 175 and a decometer……

Me

Very good! :D

Good old “Trembling two”.

[Uplinker]

Just curious but which shop are we talking about? I just spent a few days near Lincoln and may have missed a major attraction… although me credit card may hold a different opinion of course.

Yes others have got it;, down the very steep hill from the Cathedral, don't know the name of the shop, hill, or compass direction, but I could walk you there. A small shop stacked high with this sort of thing.

Just looked at a map. Yes Steep Hill; runs South from near the West door of the Cathedral.

[DogTailRed2]

Next to a very nice model shop. There is also an interesting antique shop that often has some militaria. A book shop and a couple of nice pubs. Be more Kate Bush.

[Clyffe Pypard]

At the RAE Farnborough , early sixties we had Decca in the Varsity, two Hastings and for a short time in Comet 2 XN453, (Decca in the cockpit and Decca Loran and Litton Omega down the back with the boffins).
In general the Decca worked quite well.

[binbrook]

Decca: lane slip anyone? It's a long time ago, but didn't someone bring back night photos of the main street of a German village?

[happybiker]

Decca: lane slip anyone?

We used to experience lane slip on the Canberras out of Pershore and as an observer I experienced it once in a Varsity. I never found a common problem with the receivers which caused this. Some pilots reported geographical areas where lane slip was prone to occur so I wonder if it related to loss of or distortion of the signal from one of the transmitters combined with the speed of the aircraft.

[76fan]

Decca roller maps were used by the helicopters operating over the North Sea certainly into the 1980's. For separation, odd radials out and even radials back in to Aberdeen as far as I remember.

[Cornish Jack]

Decca lane slip (on the Whirly) was, generally a result of winching - the static discharge from the cable/earth contact was the probable culprit.
That discharge could be pretty large ... we did a test sortie with the Farnborough boffins in the Littlehampton lifeboat and they reckoned that they had registered voltages around the 175k ! Forgetting to take your hand off the cable on touchdown gave an unmissable reminder ! :eek:

[ShyTorque]

I experienced the static jolt from a Whirlwind whilst being winched down to the Bridlington lifeboat, in light rain. I hadn’t been briefed and it doubled me up….I inadvertently kneed the winch man where it hurts most. He wasn’t impressed.