G-AXLR in flight showing the RB211 test engine
Photo D. Slaybaugh
Construction number 829 was built for the Royal AirForce as the fifth example of a type 1106 VC10. These type 1106s can be described as 'hot-rods', as they combine the Super wing and the more powerful RCo.43 engines with the original length 'Standard' fuselage and therefore they did not trade performance for capacity as the Super VC10 did. XR809 flew for three years with RAF 10 squadron named 'Hugh Malcolm VC' but for some unexplained reason the RAF felt able to lease the aircraft to Rolls-Royce as a flying test bed for the RB211 turbofan engine.
At that time no aircraft was available that could accommodate the large girth of the RB211 beneath the wing and still have some ground clearance left, the mounting on the side of the fuselage of the VC10 did provide this clearance. Also with the clean wing and relatively high fuselage mounting the RB211 was in clean air and therefore the test results would be universally acceptable. To be able to attach the RB211 the engine beam was strengthened to accommodate the higher weight and aerodynamic effects of the larger frontal area. Also as the RB211 was designed for a pylon mounting some other modifications were needed to adapt to the side-mounted VC10 pylon. All went well and on the first flight of the three-engined VC10 took place on 6th May 1970. On take-off, the two starboard Conways were marginally more powerful than the one RB211.
Reregistered as G-AXLR the aircraft commenced on an extensive flight test programme. Initially it flew from Hucknall, but from May 1972 on the aircraft was based at Filton from which many more flights were made. One hair-raising flight was the test bed's 44th flight on 7th august 1974. The thrust reverser on the RB211 was not used at this point but for some reason the reverser sleeve was not positively locked in the forward position. With an expected flight time of six hours the aircraft took off laden with fuel. An incremental climb was carried out, pausing every so often for re-lights on the RB211. Following a re-light with the aircraft flying at 240 knots at 20.000 feet, the cold stream reverser of the RB211 slid back into the reverse position, sealing off the bypass duct. The effect of this was a reverse idle which produced a slight lurch on the aircraft. Shortly afterwards, a more violent lurch occurred, followed by aircraft buffet. There was adverse yaw and roll, and level flight could not be maintained with full power on the Conways. The aircraft began descending at 2,500 feet per minute and, as the crew had no control over the reverse selection, the RB211 was shut down. This slowed the rate of descent but the aircraft was still descending at about 1.500 feet per minute.
Fuel jettison was initiated as the equation was quite clear to all on board - the aircraft would hit the ground in approximately twelve minutes unless the weight could be brought down to a value that the Conways could cope with. In such circumstances the time that the Conways can spend on take-off rating become academic. At 1.000 feet the aircraft weight was low enough to enable level flight on the thrust available, and a safe landing was eventually made. After this modifications were carried out to the reverser to ensure a more positive locking system.
On 26th September 1975 the aircraft was delivered to RAF Kemble. Initially the aircraft would return to RAF service but it was found that the airframe was distorted, and repairs were deemed too costly. In the end the airframe was used for SAS training purposes and was left to decay at the site, eventually being scrapped.
When later on Rolls-Royce needed to flight test the RB211-535CF and RB211-535E variants the Boeing 'house' 747 had to be hired for two 30 hour demonstrations at a total cost that just fell short of $10 million.
As all the original RAF VC10s were named after VC holders and the intention was that G-AXLR would return to RAF service the scroll honouring Hugh Malcolm VC stayed on the airframe during its time with Rolls Royce. A photo below shows that the section carrying this scroll was cut from the aircraft during its time at Kemble, sometime between 1977 and 1982, perhaps someone still has that souvenir? When in 2011 the names from other VC10s which were taken out of service were transferred to previously unnamed 101 Squadron VC10s the question of what to do with Hugh Malcolm VC came up. It was decided that this name would be added to XR808 and so after 35 years the memory of this courageous VC holder once again flies on a VC10.
1. Ex-XR809, now
G-AXLR, landing at RR Hucknall, Derby, after the first
air test with the RB211 engine on the port side
1 - 3. Several views of G-AXLR undergoing servicing with the RB211 mounted
All images provided by K. White except where noted
1. A press release from 1969 announcing the RB211 flight tests with the VC10. The photo is retouched to show what the aircraft will look like. Interesting is the statement that tests will be carried out at Lockheed's flight and test establishment! The full text is:
2. A second press release, this one from Rolls-Royce, with a photo showing G-AXLR in flight. It looks similar to the photo below (no.2) which may have been taken on the same occasion. The full text that accompanies the photo is:
view of the three-engine configuration on G-AXLR
1-3. In 1970 G-AXLR showed the three-engined layout to visitors at the (then) yearly Farnborough Airshow
1. G-AXLR seen at RAF Kemble in 1976, shortly after its retirement
1. Another shot of the derelict airframe, the tail on the left
is an ex-Dan-Air Comet
1. A cutaway drawing from Flight International showing the RB211 installation on