Stokenchurch abolished: all Wycombe pilots now officially lost (Merged)

[FNG]

I have heard it rumoured that the fun-loving chart dudes at the CAA have left Stokenchurch Mast (west of Booker, north east of Benson) off the new Southern England half mil chart. I haven't yet got a copy of the chart. Is this dastardly rumour true? Has one of the blue aeroplanes saved them the trouble by crashing into it?

Suggestions on a postcard: Which prominent nav feature/great big enormous dangerous thing would you most like to see left off your chart?

[Evo]

Which prominent nav feature/great big enormous dangerous thing would you most like to see left off your chart?


Solent zone... ;)

[rotorcraig]

Leave Pitsford off; noone would be able to find Sywell again!

RC

[Fly Stimulator]

FNG,

It is indeed true. I've just checked the new chart I bought at the London show this weekend and the mast is missing.

A few seconds work with my permanent marker has now restored it to my copy.

[Shaggy Sheep Driver]

They'll get used to it:) . Years ago, Barton power station was demolished. It was rumoured that some local pilots wouldn't be able to find base leg for 27 anymore. But they did - albeit using 'bomber' circuits:( .

Mind you, I don't know what will happen if they ever drain and fill in Leigh Flash........

As for an answer to the original question..... all controlled airspace. ;)

SSD

[IO540]

Another reason for making charts available as online downloads. No excuse for mistakes then. I did raise this with the CAA head of charts at Earls Court this week....

[Southern Cross]

Yep its gone from the chart but surely unmistakable from the air plus the small matter of the wee road leading directly to the threshold...:O

But why omit one of the true landmarks in the region particularly with the London zone so close by?

[Genghis the Engineer]

London Heathrow International.

G

[Wycombe]

Well, it was still there when I was last aviating last week.

On what grounds has it been removed - is it due to be blown-up or is it a mistook on the map?

I'm sure we'll still call "Stokenchurch for re-join" when coming from that direction whether the mast is still there or not!

Oh, and this Wycombe pilot never gets lost (or even temporarily unaware of my position)....I thank you :D

[AerBabe]

Which prominent nav feature/great big enormous dangerous thing would you most like to see left off your chart? Wales?

[FNG]

Very good idea, Aerbabe.

By the way, the official colouring-in book join the dots chart amendment website hasn't put it back on yet (just some blah about the top of the TMA going from FL lots to FL bazillion, or something)

[FNG]

Yesterday I obtained the new chart and amused myself by drawing the mast back on in splodgy blue pen, but a pilot who had just flown to Princes Risborough assured me that he saw no mast. Perhaps it is retractable in times of urgency, like Marineville in Stingray, in which case, things must be worse than we thought.

[Wycombe]

...quite possible that someone at Princes Ris didn't see the mast, it's quite a way along the ridge from there.

[eyeinthesky]

I don't suppose the map makers will be providing a correct copy with offending mast marked on it free of charge due to their oversight?? No, though not.

You really do wonder what these various agencies do and why they don't coordinate. Last year they produced a new 1:500,000 Southern Edition about a week before several important frequency changes, including that of Brize Radar from 134.3 to 124.27. I appreciate that there is a point at which the thing has to go to print and therefore not available for amendment, but they must know that these changes are coming and can plan publication to ensure the longest validity possible of information.

Also, how can you just 'lose' or forget a symbol for the highest obstacle within 30nm which has been there for years? It's not a new feature which got omitted. It is even the reason for the MSA in that sector on the SID/STAR charts for Heathrow, for heaven's sake!! :confused: :rolleyes:

[Brooklands]

Perhaps they had to leave it off to make up for last year when they included some masts in Reading that didn't exist !!

Its a good job that Wycombe don't use it as an unofficial VRP otherwise calls to visiting aircraft could be quite interesting: " G-ABCD report pasing the Stokenchurch mast - its the very big one that isn't maked on your map"

Interstingly if you ever go night flying in the vacinity of Wycombe, the brightly lit mast that you see on the edge of the Chilterns ISN'T the Stokenchurch mast - its another smaller tower at Christmas Common about 8 miles south. The lights on the Stokenchurch mast aren't very bright

Brooklands

[FNG]

Christmas Common is only a mile or two south of Stokenchurch (If you went eight miles you'd practically be in Henley). The small mast with the lights on is close to the most excellent Fox pub, a fine place to refresh after kite flying on breezy Watlington Hill.

As for the big mast, I can confirm that it was still visible through the grey haze this afternoon as I passed en route to stonk my mum's house in Thame.

[AlanM]

At 1121 ft amsl was it not used to determine terrain clearance?

[bfato]

I too went to see if it was still there this afternoon. Well OK, I was on a navex but admit to having too been intrigued by its absence from the chart.

Incidentally, whoever it was that was coming from our left, same height, on a Northerly track impressed me by not only turning to pass behind but by doing so obviously enough that I knew we'd been seen. If it were you, Mr FNG, I thank you.

[FNG]

Could have been me, but apart from a Waltham-based Pitts I only saw a couple of high-winged aircraft which were quite a bit lower than I was at the time. I was in a plain white Cap 10.

[Mike Cross]

I sent the card below to the VFR Charts Editor at the CAA
http://michael.cross20.users.btopenworld.com/images/webimages/stokenchurch.gif
He is feeling suitably abject and has published a chart amendment here (http://www.caa.co.uk/dap/dapcharts/amendmentlist.asp?chart=11)

Given the length of their relationship I suspect the mast might be further offended by being described as a new single unlit Obstacle:{

Mike

[Mike Cross]

And there's now a NOTAM as well

EGTT
OTH : FROM 04/04/19 14:11 TO PERM B0655/04
E)ANO ERECTED:
BUXTON (171F633) CHIM, S, POSITION 531549N 0015117W, HGT 2120FT AMSL
1249FT AGL, LIT
STOKENCHURCH (230D121) RTM, S, POSITION 513954N 0005522W, HGT 1111FT
AMSL 327FT AGL, NOT LIT
UK AIP ENR 5-4-1-5 AND 5-4-1-8 REFER.

Mike

Hang on!

Let's translate that thing at Buxton using the AIP's list of abbreviations used in AIS publications.
ANO is not a listed abbreviation
CHIM is not a listed abbreviation
S means South or Southern Latitude

Bu@@ered if I understand it. If CHIM is an unofficial abbreviation for Chimney it's the biggest I've ever heard of, 1249 ft high?

I'll point AIS at it and get them to correct it.

Mike

[Fly Stimulator]

From the CAA link Mike posted above...

Add new single unlit Obstacle Stokenchurch Posn 513954N 0005522W 1111(327)
New??

[DBChopper]

Is nothing sacred?!!

The next thing you know they'll knock that big golden ball thingy off the top of that stately home, fill in that big swan-shaped lake and I'll never find Wycombe again!

:eek:

[Mike Cross]

Notam now re-issued as two separate ones

EGTT
OTH : FROM 04/04/22 10:29 TO PERM B0681/04
E)AIR NAVIGATION OBSTACLE.
STOKENCHURCH (REF NUMBER 230D121) SINGLE RTM, POSITION 513954N
0005522W, HGT 1111FT AMSL 327FT AGL, NOT LIT
UK AIP ENR 5-4-1-8 REFERS.

EGTT
OTH : FROM 04/04/22 10:26 TO PERM B0680/04
E)AIR NAVIGATION OBSTRUCTION.
BUXTON (REF NUMBER 171F633) SINGLE CHIMNEY, POSITION 531549N
0015117W, HGT 2120FT AMSL 1249FT AGL, LIT
UK AIP ENR 5-4-1-5 REFERS.

So ANO means Air Navigation Obstacle. It is a chimney at Buxton, and an enormous one at that.

RTM is a new one, I assume it's Radio Telephony Mast. This abbreviation does not appear in Gen 2-2-1 Abbreviations used in AIS Publications so it's only 9/10 I'm afraid.

Mike

[Brooklands]

Christmas Common is only a mile or two south of Stokenchurch (If you went eight miles you'd practically be in Henley). The small mast with the lights on is close to the most excellent Fox pub, a fine place to refresh after kite flying on breezy Watlington Hill.

Oh dear! Obviously this Wycombe based pilot is well lost :*

Pan Pan, Pan Pan, Pan Pan: this is G-Brooklands requesting radar vectors to his sense of direction.


B

[Stan Evil]

Fear not - someone's snooked out and rebuilt it:

OTH : FROM 04/04/22 10:29 TO PERM B0681/04
E)AIR NAVIGATION OBSTACLE.
STOKENCHURCH (REF NUMBER 230D121) SINGLE RTM, POSITION 513954N
0005522W, HGT 1111FT AMSL 327FT AGL, NOT LIT
UK AIP ENR 5-4-1-8 REFERS.

[AlanM]

Just a small irrelevant point - but I learnt that it was 1121 feet amsl.

I have just checked the RVA chart for EGLL dated October 2003 and it still says 1121 feet - NOT 1111 feet.

not that important really (unless you fly at 1112 feet!!!) but does make you wonder about the quality and accuracy of the info published.........

(i'll be ******ed if I can see it on the page quoted....):(

[Taildragger]

The CAA have missed the mast at Stokenchurch off the latest 1:500000 Chart published on the 15th April. This mast is situated approx 6.5 nm NE of RAF Benson and is on the ridge just above a strip called Lewknor, which IS marked.
The mast is situated 2 nm due East of Lewknor and has a height amsl of 1141 ft. If you look at the new chart, the spot height marked on the M40 motorway of 837 is right beside the mast.
APPROX repeat APPROX co-ordinates are N51.39.7 W000.55.3
Check your old charts and be aware that this mast is there, and don't go haring around there in the grotty weather which can be prevalent in this area due to the ridge, without being aware.
I guess the CAA will Notam this in due course, but if I were you I would mark the spot in indelible ink.!! :uhoh:

[Practice Auto 3,2,1]

Taildragger,

If you want to have a looksy here (http://www.pprune.org/forums/showthread.php?s=&threadid=127080) you will find a thread from little while ago on the same topic.

Its already marked on my new map just as you suggest :D

[Hairyplane]

OK - they missed a mast off and durned if it wasn't a biggy...Oops!

A free-issue self adhesive overlay - I remember that the CAA did this when London City came into being - might be a good idea.

On the plus side, how useful or what is the decsion to add the 4 letter ICAO designators a la Jeps charts.

Along with presumably many other pilots, I responded to the 'how can we improve our charts' thread by making this suggestion. They listened!

THanks for the tip, the magic marker is coming out right now.

BTW - I wonder how many pilots religiously update their charts?

I remember as a student pilot in 1975 looking at my instructors chart. My attention was drawn to it because the sea was a very dark blue.

On closer inspection it had the London balloon barrage pencilled in across the Thames!

He was an ex WW2 fighter pilot.

Brian Hunter where are you? Last heard of at Stapleford.

HP

[IO540]

Time for everybody to write to the CAA and demand online downloadable charts.

[rotorcraig]

We spoke to CAA Charts man about this at the London Air Show.

He agreed that an online solution would be best for all, and said that CAA currently lose money on charts, due high cost of prodution.

Told us that an online solution is waiting on resolution of licencing issues with Ordnance Survey who own underlying data, also on redistribution of responisbilities between CAA and NATS.

RC

[IO540]

We must have spoken to the same man :O

The CAA already make the data available in some way to the makers of MemoryMap, the PDA-based moving map GPS software. I don't know if MM just scan in the CAA charts (under an agreed copyright agreement with the CAA/OS) or whether they get them in electronic form. The CAA charts man didn't know either. It should be evident if one looks at the MM database formats; if they are Jpegs or similar, they are most likely just scanning the charts.

I am sure that today the charts are produced electronically, in vector format. This is much better than scanning in a printed chart, descreening it, and ending up with massive graphic files which incidentally cannot be searched for text etc.

[Boing_737]

The charts used for Memory Map are of some proprietary format I think, especially as with the same file, you can switch between half-mill and quarter-mill charts, so I am guessing that they are in the same file, and the software just loads it all into memory and accesses different parts for different charts. The file also must contain some headers that can calibrate the maps in the software so that accurate positions can be plotted. If you want to know more about this sort of thing visit OziExplorer (http://www.oziexplorer.com) . Lots of useful info on the page when you dig around where map its map calibration process is (or used to be) explained.

If the maps are produced in vector format, someone would be able to produce a really wizard GPS with a full moving CAA chart that would be able to automagically route you around controlled airspace, danger areas, restricted areas etc. This would be really useful, therefore the chances of it happening are very slight .;) (it would also mean that rather than downloading a new map each year @ £46 a pop as with Memory Map, you'd just need to download the updates for maybe a small registration fee). Its worth noting that PocketFMS (http://www.pocketfms.com) does something similar (although its a GPS rather than a map as such), but relies on the community at large to enter data into their database (but then its free to download, and relies on donations of 50 euros to help support it). The point being, if someone can produce something this complicated and provide it for a small one off donation, then surely the CAA could do something similar.

Slightly veered off topic, but I guess in summary I would say that if the CAA/OS could sell an electronic map for £X that you could update each year without forking out all that money it would:

(1). Ensure that your map data was always up to date
(2). You would only need to print out the bits you need rather than carting around the whole map and deal with folding it in the cockpit.
(3). Mistakes like missing the Stokenchurch mast can easily, and cheaply be rectified (no need to for stick on bits).
(4). A real funky GPS moving map could be produced

I guess the downside is if you need or want to carry the whole map, you need to find someone with a huge A0 printer.

[Fujiflyer]

Boing_737, interesting you mention OziExplorer. I bought the software last month and have scanned a couple of maps in and "calibrated" them. I am very pleased with it - so far I have used it for (non flying) outdoor activities. It is easy to use and powerful. At the mo' I plan a route on the digital map in OziExplorer and upload it onto my (basic) gps which then points to each waypoint in turn.

Fuji

[FNG]

I think that the previous thread about this had better jokes.

[Taildragger]

Ta Practice Autp. I guess it bears repeating though.
Chias

[glider12000]

they have also missed out the tower in portsmouth. Although its not finished its still huge!

[Mike Cross]

EGTT
OTH : FROM 04/04/22 10:29 TO PERM B0681/04
E)AIR NAVIGATION OBSTACLE.
STOKENCHURCH (REF NUMBER 230D121) SINGLE RTM, POSITION 513954N
0005522W, HGT 1111FT AMSL 327FT AGL, NOT LIT
UK AIP ENR 5-4-1-8 REFERS.

Also see
The Chart Amendments (http://www.caa.co.uk/dap/dapcharts/amendmentlist.asp?chart=11) There are 12 to this chart already.

Remember there is fair amount of time between the closing for press and the thing hitting the streets.

[email protected] will be happy to receive information on new prominent landmarks for inclusion on the site and on old landmarks that may no longer be prominent (like the radio telescope that remained on the chart for several years after it was dimantled)

Mike

[Taildragger]

Ah well....my co-ordinates weren't far out anyway.!!

[PPRuNe Radar]

I don't know the particular mast being refered to. Is the problem that a nav feature has been missed off with nothing else suitable in the area as a visual reference for navigation ??

Or is the problem one of terrain clearance ??

If the latter, then people will of course be aware that there can be unmarked obstacles up to 300' agl at any point on a chart.

The mast is situated 2 nm due East of Lewknor and has a height amsl of 1141 ft. If you look at the new chart, the spot height marked on the M40 motorway of 837 is right beside the mast.

That could put an unmarked mast or similar object up to 1137' amsl in this area - a whole 4' under the Stokenchurch one quoted.

Anyone who can either fly that accurately, or is basing their minimum safe height on a difference of that margin must be an incredible pilot !!!

[IO540]

To be fair, nobody should get killed because the MSA due to the 837 elevation is 1900ft which puts you comfortably above the 1200ft mast :O

[Fujiflyer]

PPRuNe Radar, as you say the omission is not really a hazard as such, but the "publicity" is more down to the fact that for years the mast was depicted on the 1/2 mil VFR charts, only for it to vanish from this year's prints,

Fuji

[PPRuNe Radar]

Thanks Fuji, fair point being made then :ok:

I just assumed from the original post that it was a possible hazard to the scud running community ;)

Check your old charts and be aware that this mast is there, and don't go haring around there in the grotty weather which can be prevalent in this area due to the ridge, without being aware.

[DOC.400]

I heard that the military were not happy that the mast was shown in the correct position on previous maps and that in the process of moving it (on the map!!) it got left off.......doh!

Understand that this mast is one of half a dozen around the country that are designed to withstand a nuclear blast. Upto 2-3' of concrete can be wiped of the sides without affecting its stability. When the dust has settled, new comms antenna could then be installed.......

Hopefully, we're beyond that now...what time is the Domesday Clock anyway?

DOC

[FNG]

I'm generally a big fan of GASIL, but it's a bit cheeky of the current edition to tell us that the Stokenchurch chart faff is all our fault. We carelessly didn't spot it being removed on the chart updates website some time last year, and recklessly failed to tell the CAA about this. What twits we are.

(page 18 of http://www.caa.co.uk/docs/33/srg_gad_gasil2of2004.pdf )