#TheXH558Story - Part 4
Mar 3, 2017 by Ian Homer. Posted to category: General
In May 1953 VX770 was fitted with 7,500lb thrust Armstrong Siddeley Sapphire turbojets for high-speed high-altitude trials, as the Olympus powerplants were not yet operational. The second prototype, VX777, was nearing completion, and featured a longer nose and bomb-aimers blister, and would finally receive the 9,750lb thrust Bristol Olympus Mk 100. Falk had considerable input on the cockpit instrument layout, and at his suggestion the conventional control wheel that had been used on VX770 was replaced with a fighter-style control stick. The maiden flight took place on 3 September 1953, and the aircraft appeared a few days later at Farnborough accompanied by sister aircraft VX770 and all four Avro 707s.
What a sight this must have been! A Delta flypast at Farnborough in 1953 - Courtesy of www.aviationphotocompany.com
A comprehensive programme of system trials was underway by the spring of 1954, but Vulcan trials then suffered a severe blow when VX777 was badly damaged in a heavy landing at Farnborough. Avro continued the programme as best it could with VX770, finally commencing high-speed, high-altitude trials, and now the delays that had seen the Type 698 overtake the 707 programme bit hard.
VX777 landing at Farnborough. From a negative held by Trust graphic designer and aviation enthusiast, Mark Freshney.
Trials with the 707A had recently revealed the airframe vibrated badly at high speed and altitude, and this data was confirmed by VX770. Airflow was separating from the outer wing upper surfaces, causing a compressibility stall between 0.8 and 0.85M, well below the speed that could be achieved by Olympus-powered Vulcans. Avro experimented with vortex generators and wing fences, but the only solution would be to redesign the leading edge of the wing.
The straight edged wing was swept at a constant 52 degree angle; this was decreased by 10 degrees at mid span, then brought back to 52 degrees further outboard, adding a slight droop at the same time. The design was tested on the Type 707 WD280 in 1954 and succeeded in pushing back the compressibility buffet beyond the speeds and altitudes that would be encountered by the Vulcan. The solution came at a price though. All leading edges already on the production jigs had to be scrapped, and the jigs themselves rebuilt. Additionally, the solution came too late to be incorporated into the first production Vulcan B1, XA889, completed in January 1955. Shortly after, a repaired VX777 re-joined the test programme, and after being given the new leading edge in July it became the first to begin flight trials with what was now known as the Phase 2 wing.
By now two production Vulcans were flying, XA889 being joined by XA890, the latter gaining notoriety for performing an upward barrel roll in the hands of Roly Falk at the 1955 SBAC show.
See both the flypast and the later barrel roll by Roly Falk in this video.
VX770 and XA889 underwent acceptance trials at A&AEE, and the Vulcan was cleared for entry into RAF service on 29 May 1956, with the first B1 (XA897) delivered to 230 Operational Conversion Unit at RAF Waddington on 20 July. Several of the initial production batch had been allocated to development and testing programmes and in fact, 230 OCU only had their hands on XA897 briefly before it was returned to Woodford for modifications and replaced by XA895.
The reason for XA897s withdrawal soon became clear. The modifications included the installation of bomb-bay fuel tanks, increasing the aircraft’s range by 700 miles. On 9 September 1956 it took off from Boscombe Down for the long flight to New Zealand and Australia to take part in a display for Air Force Commemoration Week.
The trip was viewed as a valuable opportunity to promote and prove the aircraft, being the first long-range flight the Vulcan had undertaken. A crew hand-picked for their experience and skill had been assembled, captained by Squadron Leader Donald Howard, with the Commander in Chief of Bomber Command, Air Marshal Sir Harry Broadhurst as co-pilot. All the remaining three RAF crew were Squadron Leaders, with one civilian aboard, Avro technical service representative Frederick Bassett. The outbound flight went smoothly, with the 11,475 mile distance to Melbourne covered in 47 hours 26 minutes including stopovers at Aden and Singapore, a total flight time of just 23 hours 9 minutes. Broadhurst took the opportunity to point out to Australian ministers that neither their front-line fighter, the American Sabre, nor any similar type would be able to catch the Vulcan!
After visits to Sydney, Adelaide and Christchurch New Zealand the long return flight began. In the early morning of 1 October the Vulcan departed from Aden on the last leg, Broadhurst in the co-pilot seat and alternating with Howard at the controls. A VIP reception at London Heathrow Airport eagerly awaited the arrival, though poor weather surrounded the area with rain and mist. The first thing the waiting crowds were aware of was the sound of a burst of full power, followed by the Vulcan climbing steeply to about 800ft, where the cockpit canopy released and the two forward crew ejector seats fired. The aircraft then dived to starboard, crashing on the edge of Runway Four where it exploded on impact, killing the four rear crew members.
See newsreel footage of the trip and the aftermath at London Airport in this video.
Sadly, it was not to be the first incident relating to the development of Vulcan aircraft. We continue the story next week, with other images appearing on social media with the hashtag #TheXH558Story
Selected extracts in this article are from the range of Vulcan to the Sky publications that can be found in our bookstore. CLICK HERE TO VISIT.
If you wish to support Vulcan XH558's Survival Plan, please do visit our Just Giving donation page. Thank you for anything you can give.