A Spitfire IXT was planned to fly a shakedown flight for an upcoming flight display season from Coventry Airport (United Kingdom) After the normal flight preparation was completed the aircraft took off, with a positive rate of climb the gear was selected up, and the gear retracted normally. Onboard the pilot and a passenger (this is a two-seater version of the Spitfire)
The aircraft after the belly landing (©FP - Duncin Cubitt, L. Hatton)
When during a practice manoeuvre the gear was selected down the undercarriage lever could not be moved to the full down position, and the gear remained up and locked.
The landing gear lever on the Spitfire has a large throw as it operates the up-lock and down-lock, as well as a valve to control the hydraulic pressure to the landing gear retraction actuator.
It was reported that the final part of the lever movement estimated to be ~1 inch (.2.54 cm), was blocked. Two more attempts were made by cycling the landing gear lever. It locked normally in the up position (Gear up and locked) but the final movement in the down section could not be made.
The pilot attempted several "methods' to extend the gear from both the forward and the aft cockpit under varying flight conditions and G-loading. The G-load during the different manoeuvres varied from +5g to -1g. All to no avail. The last option for the crew was to use to pneumatic "blow-down" system. The pilot decided against using this as it could leave him with;
Both undercarriages might not lockdown
One gear locking down and one remaining unlocked
Using the "blow-down" system would disable the gear retraction system
The landing gear control lever (centre of picture) on a typical Spitfire, not the incident aircraft (source Stackechange.con ©Unknown)
He, therefore, decided to perform a power-off landing with full flaps and the gear selected up, on the grass of Coventry airfield.
The crew member was instructed to tighten his harness and latch his canopy open while he jettisoned his own canopy over the field (later the experienced Spitfire pilot, 930 hours on type, informed investigators that the forward canopy of the two-seat Spitfire will not latch open in flight) While flaring the aircraft he switched off the magnetos and the main fuel cock and touch down at a speed of 65 knots. After a sliding, for only 100 yards the aircraft came to a stop and both occupants evacuated the aircraft without injury. After the landing, the aircraft was recovered and the ger handle moved normally, and the gear retraction and extension were working accordingly. It was found that an unused cable guide from the landing gear selector was laying on the cockpit floor. Its retaining screw had come undone and blocked the handle movement. It is suspected that it fell out of the selector during the forced landing The aircraft was restored to flying condition by volunteers of the Battle of Brittain Memorial Flight The incident was investigated by the Air Accident Investigation Branch, their report with additional details is available on their website. Click here for direct access.
The aircraft in its element in October 2021 ©Keith Holden
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