Date:	Monday 9 December 1957
Time:	day
Type:	English Electric Canberra B.2
Owner/operator:	RRE RAF
Registration:	WK129
MSN:	R3/EA3/6643
Fatalities:	Fatalities: 2 / Occupants: 2
Aircraft damage:	Destroyed
Location:	Ffynnon Llyffant above Cwm Eigiau, Carnedd Llwellyn, Caernarvonshire -   United Kingdom
Phase:	En route
Nature:	Test
Departure airport:	RAF Pershore, Worcestershire
Destination airport:
Confidence Rating:	Information is only available from news, social media or unofficial sources

Narrative:
The crew were taking part in testing in conjuction with a Ministry of Supply radar unit positioned on the summit of nearby Drum. After completing the test Flt Lt Bell radioed to the radar operators stating that they were returning to base. When nothing further was heard from the crew a search was initiated, the radar unit had tracked the aircraft until it was some 10 miles north of Drum but there was no track beyond there.

Later the wreckage was discovered by search parties on the northern side of Carnedd Llewelyn. The aircraft had been flying in patchy low cloud on an easterly track when it struck Carnedd Llewelyn some 300 feet below the summit on the ridge connecting the mountain to Foel Grach. The forward end of the aircraft broke up leaving many pieces of structure from the forward fuselage on western side of the ridge. There is then a break in the wreckage trail which starts again on the eastern side of the ridge on the slopes above Ffynnon Llyffant. The centre section, wings and rear fuselage eventually crashed to earth near this small lake, though other pieces did travel some distance beyond here.

The reason for the aircraft being below its safety height could not be ascertained, a possibility was put forward by the crew's commander as engine failure due to icing. That day icing conditions were expected above 3,000ft.

Both crew killed:
Flight Lieutenant William Albert Bell (pilot, Radar Research Establishment, aged 31) - killed on active service 9/12/1957
Flight Lieutenant Kenneth Charles Frederick Shelley (navigator, aged 27) - killed on active service 9/12/1957

At an inquiry into the accident, the cause was deemed undetermined,but a contributory factor may have been icing.

The Canberra crashed in an area once dubbed by the men of the RAF Mountain Rescue Team at Llandwrog during the war, `The Graveyard` because so many aircraft had crashed in that area where cloud often shrouds the mountain tops.

Note: RRE = Radar Research Establishment. The debris was flung some considerable distance. The Canberra struck the other side of the ridge and was hurled over and down into the cwm. Pieces of wreckage - including both engines along with the main wheels and tyres - were still present in 2012 in Llyn Llyffant

1. Halley, James (1999) Broken Wings – Post-War Royal Air Force Accidents Tunbridge Wells: Air-Britain (Historians) Ltd. p.194 ISBN 0-85130-290-4.
2. Royal Air Force Aircraft WA100-WZ999 (James J Halley, Air Britain, 1983 p 64)
3. Category Five; A Catalogue of RAF Aircraft Losses 1954 to 2009 by Colin Cummings p.272-273
4. http://www.ukserials.com/losses-1957.htm
5. http://peakwreckhunters.blogspot.com/search/label/Canberra
6. http://www.peakdistrictaircrashes.co.uk/crash_sites/wales/english-electric-canberra-wk129-carnedd-llewelyn/
7. https://geotopoi.wordpress.com/2009/10/10/ffynnon-llyffant-english-electric-avro-canberra-b-mk-2-wk129-radar-research-establishment-9-dec-1957-4/
8. http://www.geograph.org.uk/photo/910130
9. http://aircrashsites.co.uk/air-crash-sites-5/canberra-wk129/
10. https://53degreesnorthadventures.wordpress.com/2017/01/20/the-search-for-flight-wk129/
11. https://terryjameswalker.wordpress.com/tag/carneddau/
12. https://www.thunder-and-lightnings.co.uk/memorial/entry.php?id=253
13. http://www.ukserials.com/results.php?serial=WK
14. https://hillcraftguidedwalking.com/2017/02/18/217-the-carneddau-and-llyn-llyffant/
15. https://cityseeker.com/bangor-gb/895237-llyn-llyffant
16. https://simviation.com/lair/casualty1957.htm

Date/time	Contributor	Updates
17-Jun-2008 15:14	JINX	Added
05-Apr-2013 14:05	Dr. John Smith	Updated [Cn, Departure airport, Source, Embed code, Narrative]
26-Jul-2013 14:54	Dr. John Smith	Updated [Source, Embed code, Narrative]
19-Mar-2015 10:23	TB	Updated [Operator, Location, Embed code]
20-Oct-2019 18:40	Dr. John Smith	Updated [Time, Operator, Embed code]
05-Nov-2019 10:36	Nepa	Updated [Operator, Nature, Narrative, Operator]
15-Aug-2020 21:25	Dr. John Smith	Updated [Location, Narrative]
15-Aug-2020 21:41	Dr. John Smith	Updated [Source]