Date:	Wednesday 3 June 1970
Time:	12:00
Type:	Zlín 526A Akrobat
Owner/operator:	Neil Williams
Registration:	G-AWAR
MSN:	1036
Fatalities:	Fatalities: 0 / Occupants: 1
Other fatalities:	0
Aircraft damage:	Destroyed
Category:	Accident
Location:	Hullavington, Chippenham, Wiltshire -   United Kingdom
Phase:	Manoeuvring (airshow, firefighting, ag.ops.)
Nature:	Demo/Airshow/Display
Departure airport:	Hullavington, Chippenham, Wiltshire (EGDV)
Destination airport:	Hullavington, Chippenham, Wiltshire (EGDV)
Investigating agency:	AIB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
Zlin Z-526A Akrobat G-AWAR: Written off (destroyed) 3/6/1970 when crashed during aerobatics display practice at Hullavington, Wiltshire. The aircraft's wing failed and folded up due to stress fatigue cracking. According to contemporary press reports, and the official AAIB report into the accident:

"The cause of the wing folding on the Zlin Z526A G-AWAR flown by Mr Neil Williams on June 3, 1970, has been officially attributed by the chief inspector of accidents to a fatigue failure in the centre-section lower spar boom.

When operated in excess of +6g and -3g, the Z526 is limited to an aerobatic life of only 100 hours. Following the incident, which led to a crash landing in which the pilot was unhurt, the manufacturers, Moravan, examined every aircraft likely to be involved in aerobatics. Out of 100 examined, two Z526As were found to have cracks in the same position as G-AWAR, both having flown a comparable number of hours.

Metallurgical examination of the failed specimens showed that no material failure or deficiency had initiated the cracks. It was consequently considered that the load limitations were inadvertently exceeded, bringing about a reduction in the fatigue life of the structure".

Registration G-AWAR was cancelled the same day (3/6/1970); however, the cancellation was probably retrospective, as the CAA documentation also noted as "notified 13/10/1970"

1. AAIB: https://assets.publishing.service.gov.uk/media/5422fa24e5274a1314000757/15-1971_G-AWAR.pdf
2. CAA: https://cwsprduksumbraco.blob.core.windows.net/g-info/HistoricalLedger/G-AWAR.pdf
3. Flight International 30 September 1971: https://www.flightglobal.com/pdfarchive/view/1971/1971%20-%201950.html?search=cessna%20skyhawk
4. http://1000aircraftphotos.com/Contributions/SmithRon/10439L.jpg
5. https://www.key.aero/forum/historic-aviation/125691-neil-williams-zlin?p=2868508
6. http://www.aviadores.eu/williams.html
7. https://forums.flyer.co.uk/viewtopic.php?t=99305
8. G-AWAR at Biggin Hill (EGKB) 17-05-1969: https://abpic.co.uk/pictures/view/1512849

Date/time	Contributor	Updates
17-May-2008 11:10	ASN archive	Added
24-Dec-2010 14:09	TB	Updated [Aircraft type, Total fatalities, Other fatalities, ]
15-Jul-2012 08:35	Dr. John Smith	Updated [Time, Operator, Source, Narrative, ]
13-Nov-2012 03:29	TB	Updated [Operator, Source, Narrative, ]
08-Jun-2013 11:02	Dr. John Smith	Updated [Operator, Source, Embed code, Narrative, ]
30-Jun-2013 19:12	TB	Updated [Time, Operator, Source, Embed code, Narrative, ]
17-Oct-2015 19:44	Dr.John Smith	Updated [Operator, Location, Departure airport, Destination airport, Source, Narrative, ]
17-Oct-2015 19:44	Dr.John Smith	Updated [Source, ]
12-May-2016 16:55	TB	Updated [Operator, Location, ]
30-Sep-2020 22:57	Dr. John Smith	Updated [Operator, Location, Departure airport, Destination airport, Source, Narrative, Accident report, ]