Part 2 of the trail saw Twinwood receive new aircraft in the form of the Tomahawk and then the P-51 Mustang. But that did little to alleviate problems on the base.

Newly delivered, the Mustangs soon found themselves grounded awaiting much need repairs and spare parts, none of which were readily available. But a change was coming, and soon, 169 Sqn was able to depart.

By 15 July, all but one of the Mustangs  – which was still awaiting repairs – had left Twinwood and were at their new base at Doncaster. A new era was about to begin for them.

While 51 OTU continued to perform its training duties, other squadrons continued to come and go. The next to arrive was 239 Sqn, another Mustang Mk.I unit, which arrived at the end of August 1942.

The Mustangs had been patrolling the skies along the south coast around Brighton and Beachy Head, and as far inland as Gatwick, their former station. No sooner had they arrived than a small detachment was sent to Snailwell, leaving the squadron split between three airfields: Gatwick, Twinwood and Snailwell.

The Snailwell section took part in exercises and returned briefly in early September, only to transfer to Castle Camps to take part in further Army Co-operation activities. The Gatwick section continued covering the south coast, while those newly arrived at Twinwood practised night landings in their Mustangs.

This fluid movement at Twinwood continued until 22 October, when the entire squadron moved to Cranfield to take part in further exercises. This effectively ended its association with Twinwood.

At Twinwood, night training was always hazardous, even for experienced pilots. A nearby homestead, Rutters Cottages, was the site of a tragedy on 28 November 1942, when one of 51 OTU’s Havocs crashed close by. Its pilot, Sergeant Leonard James Casey, was sadly killed. A New Zealander from Herne Bay, Auckland, Casey was just 21 years old and was buried in Kempston Cemetery.*⁶

His aircraft, Havoc I BJ501, was undertaking a solo night-training exercise and, at the time of the crash, was carrying out overshoots. As the aircraft pulled away it suddenly entered a dive and crashed. Casey was not killed outright, but was taken to Bedford County Hospital, where he later died from his injuries.

The Americans arrive and a reshuffle takes place.

By early 1943, the Eighth Air Force was gaining strength in Britain – the friendly invasion had begun. Lacking experience in night-fighter operations, the USAAF began sending airmen to Twinwood, where it was hoped they would benefit from British expertise, particularly that of the OTU.

One of these American units was the 417th Night Fighter Squadron, which arrived via Scotland on 11 May 1943.

Constituted as the 417th Night Fighter Squadron on 17 February that year, the unit came under the control of VIII Fighter Command, attached to the RAF. Its journey here began at Orlando Air Force Base, before moving to Kissimmee and eventually to Ayr on Scotland’s west coast, where a small detachment remained.

Training in the United States had been undertaken on the P-70, a converted Douglas A-20 Havoc/Boston. The purpose of the conversion was to provide the USAAF with an airborne radar interception capability, something it lacked at the time. With upgraded engines, the P-70 also carried the British Mk. IV radar, specifically designed for airborne interception. Intended as an interim solution until the Northrop P-61 Black Widow became available, only 160 P-70s were ever converted.

Once in the UK, however, the men of the 417th found themselves training on Bristol Beaufighters rather than the P-70s with which they were familiar.

Conversion and training began quickly and progressed well however. Before long, the Americans were ready for their own aircraft and were transferred to RAF Scorton in North Yorkshire, where some twelve Beaufighters duly arrived. Training continued there until August, at which point the squadron was declared ready for combat.

Their theatre of operations, however, was not to be the dark skies of Europe but the warmer climate of Algeria. The squadron would eventually receive its P-61s, but not until March 1945, when it returned to Europe to undertake night-fighter duties protecting Allied bridgeheads as the advance into Germany continued.

It was also during 1943 that a renumbering of training units led to the resident 51 OTU, along with other OTUs across the country, being renumbered. This was connected with Operation Saracen, later revised as Operation Banquet, the contingency plan for countering a German invasion of Britain. Under the scheme, OTUs had 500 added to their existing numbers, redesignating them as squadrons. Thus, 51 OTU became 551 Sqn.

While some units readily adopted their new numbers, many continued to be referred to by their original OTU designations. Consequently, when 51 OTU became 551 Squadron RAF on 17 September 1943, it continued its night-training duties much as before. In practice, little changed and, as with many of these newly numbered units, no formal change in organisation took place, nor were they ever formally recognised as RAF squadrons in their own right.

1944 – winds of change.

Between 5 and 13 January 1944, a small detachment of 164 Sqn, equipped with Hurricane IVs and Typhoon IBs, visited Twinwood. Whilst here, they carried out practice dive-bombing attacks against mock targets, while the bulk of the squadron remained at Fairlop flying armed sorties.

They would stay briefly but return for another short period in February, when further practice flights involved ground strafing and battle-formation flying. The late-winter rain, however, curtailed many of the planned activities, with some days seeing no flying at all.

Although US aircrew had previously been present at Twinwood, no American aircraft had been located there. That changed on 29 January 1944, when during a ferry flight to King’s Cliffe, the right engine of P-38J 42-67873 failed while the aircraft was approaching the airfield. As the pilot attempted an emergency approach, the left engine also failed and a wheels-up landing was made. The aircraft, flown by Harry V. Dulick, was believed to have been salvaged and returned to service.

During 1944, Twinwood acquired a second identity: USAAF Station 506. This appears to have been an American administrative designation rather than a replacement for its RAF identity. The airfield remained RAF Twinwood Farm, while its location and facilities brought it into the wider network supporting the United States Eighth Air Force. The official USAAF designation was Milton Ernest (Twinwood Farm), Station 506.

The significance of this American connection was greater than a simple alteration of name. By 1944, VIII Air Force Service Command had become the vast logistical organisation responsible for keeping the Eighth Air Force operational across Britain and, following D-Day, on the Continent. Its headquarters was located at nearby Milton Ernest Hall, and Twinwood provided a convenient airfield for the movement of liaison aircraft, personnel, mail and equipment. The two sites were only a few miles apart, making Twinwood a useful addition to the American headquarters.

RAF activity continued alongside and dominated this American use. The night-fighter training role remained the airfield’s principal function, even after the resident training unit had been redesignated 551 Squadron in September 1943. The American presence was therefore an additional role rather than a complete takeover of the station. In fact, few local residents would have realised that their familiar RAF station was now being used as part of the wider logistical network supporting one of the largest air forces ever assembled.

It was this American connection that would ultimately secure Twinwood Farm’s place in popular history. Without the relationship between the airfield and the nearby headquarters of VIII Air Force Service Command, it is unlikely that one of the world’s most celebrated bandleaders would ever have passed through its gates. Yet, on a cold December day in 1944, the routine departure of a small American liaison aircraft would transform an otherwise unassuming Bedfordshire airfield into the setting for one of the Second World War’s most enduring mysteries.

With the arrival of American forces nearby a new association has begun. But this link, does little but lead to an intriguing mystery that has perplexed historians ever since. In the last part of the trail we see how Twinwood becomes famous and how its post war future looks temporarily bright.

The full story of Twinwood Farm can be found in Trail 67.