Moths, mosquitos and other flying things

If you couldn’t make it to our museum trip on 5th August, you missed one of the most interesting events so far this year. I’m talking of the De Havilland Aircraft Museum, a gem hidden near London Colney, just off the St Albans junction of the M25 where six cars – and a motorbike – from the club arrived to be given one of the most informative and entertaining guided tours that your scribe has had the pleasure of receiving in any museum.

Ably organised by our Vice Chairman, Graham Cook, we arrived at Salisbury Hall, a sixteenth century moated manor house set in the Hertfordshire countryside, on a bright Sunday morning. The site is old, dating back to the first century and used during the Roman occupation, now taking its name from a previous inhabitant, the Earl of Salisbury. Famous occupants of the current house have included Nell Gwynne, Lady Randolph Churchill and Sir Nigel Gresley, chief engineer of the LNER. It later came into the hands of Sir Geoffrey de Havilland who established the aircraft company after first cutting his engineering teeth with the Wolseley Tool and Motor Car Company in Birmingham and, later, the Motor Omnibus Construction Company Ltd of Walthamstow, where he designed his first aero engine.

He was one of Britain’s first aviation pioneers (UK pilots certificate number 12) who flew his first aircraft, with no prior experience, in 1910. Well, they didn’t go as fast then. The plane he flew became the first aircraft to be bought by the British Government. He was both the designer and test pilot – no pressure there, then! His planes played a major role with the Royal Flying Corps in WW1 being used as fighters, reconnaissance aircraft and bombers.

In 1920, the de Havilland Aircraft Company was formed at Stag Lane Aerodrome in Edgware Road, designing and building Tiger Moths. Later, moving to Hatfield in 1930, he completed his new factory there in 1934. During WW2, it was this factory which produced the famous Mosquito and later entered the jet age with a series of twin boom fighters named Vampire, Venom and Sea Vixen. The world’s first jet powered passenger airliner, the Comet, was produced here, followed by the Trident and the UK’s most successful passenger jet, the BAe 146.

Did you know Sir Geoffrey was a bit of an insect lover? This goes to explain why he gave his planes names like Moths, Queen Bees, Hornets, Wasps and, of course, Mosquitos. Incidentally, Nigel Gresley was a bird watcher, or something similar, and he named his locomotives after some of our feathered friends; Mallard springs immediately to mind. Not a lot of people know that.

With the Jags – and the Triumph – parked in the museum grounds with a DH 121 Trident 2E as a photogenic back drop, we met our guide, the museum curator, and commenced our tour. The list of exhibits is too long to describe here, so I will select a few that caught my eye…

The DH 53 Humming Bird (not an insect) was de Havilland’s first light aeroplane. Built in 1923-24. Used by the RAF for experimental work including being launched from and retrieved by an airship (the R-33).

For Bond fans, they have an Autogiro (C.24) on display in unrestored condition. It is the only rotorcraft de Havilland ever built and this one was the first and the last – pretty rare then. Designed by its inventor, Juan de la Autogiro – no, only kidding, de la Cierva – it had a cabin of the DH Puss Moth making it the first enclosed Autogiro.

Probably one of the most familiar names for an early plane is the Tiger Moth (there, an insect at last). These were built over a relatively long period and quite a few are still flying. This one was built at Hatfield in 1939 and used for pilot training in the War, as many were. In 1956 it was converted for crop dusting and retired in 1961. Note the centre section top wing support struts are forward of the cockpit to make bailing out when wearing a parachute easier. Around 9,000 were built.

The DH 82B – Queen Bee – was a low cost target aircraft. It could be flown manned, but this did place the pilot at some risk of being shot. To the relief of many a pilot, in 1935 at Farnborough, it was flown by remote control. It was operated from the ground receiving simple instructions via radio, which were selected using a standard telephone dial of the type seen in old phone boxes. The plane towed streamers behind as the targets. These radio controlled planes were called worker bees or drones since the aircraft they were adapted from was the Queen Bee. The name ‘drone’ still applies to this day (and not many people know that either) The one on display is a 1943 example restored by the museum in 1986.

In the next hanger we found the DH 98 Mosquito…and two more variants. This was the plane we had really come to see. It is THE prototype and the only surviving first prototype of a twin engine piston powered WW2 combat aircraft. De Havilland proposed it to the ministry as a fast unarmed bomber and, after many rejections a prototype was ordered in December 1939.

Designed and constructed at Salisbury Hall, the Mosquito had an estimated top speed of 397 mph at 23,700 feet with a range of 1,480 miles. Following its maiden flight, during which it out-performed their expectations, the Ministry ordered 150.

To save on strategic materials such as aluminium, de Havilland constructed the Mosquito in wood, as it had done with many planes previously. This was basically balsa wood sandwiched between two thin layers of ply and shaped around concrete moulds (also on display). Unfortunately,  standard aircraft factories were not geared to this type of construction in wood. The answer… subcontract it out to Britain’s furniture makers!

Total production amounted to 7781 aircraft. This prototype was ordered to be destroyed – ‘take it into a field and burn it’ – but, thankfully, the chap in charge  of destroying it disobeyed his orders and kept the plane hidden, moving it from one storage facility to another over the years until, eventually, the museum acquired it.

This prototype became the fastest mosquito ever flown attaining a maximum speed of 439mph. There are around four variants manufactured and the museum has two of them. One was the B.MK.35 bomber, adapted to take a 4000lb high capacity blast bomb. The museum’s example was built in Hatfield in 1945, retired from service in 1959, flew in the film 633 Squadron (1964) and finally ended its flying days in 1968.

The third Mosquito is made up from an original fuselage, with wings of a Sea Mosquito, recovered in Israel in 1980. This model is an FB Mk VI, the most widely produced variant and was basically a fighter–bomber equipped with four Browning machine guns in the nose and 20 mm Hispano cannons in the belly. Oh, it also carried two 500lb bombs internally and another two under the wings. Not a holiday charter then! But we will come back to this in a little while.

In 1943, De-Havilland produced its first jet-powered aircraft, the DH100 Vampire FB6. A great advance, but still using the balsa/plywood sandwich semi-monocoque for the pod structure. They made 4376 of these. The one at the museum was built at Hatfield in 1949 and supplied to the Swiss Airforce who donated it to the museum in 1974. Other ‘V’ jets on show included a Sea Vixen and a Sea Venom.

There are far too many exhibits to talk about here, however we cannot finish without a mention of that plane made famous by Dan Air on many an early package holiday to Spain and beyond, the DH106 Comet 1A. The world’s first turbo jet-powered airliner, and what a beaut! With swept-back wings mounted below a pressurised cabin and with the engines buried in the wings, it was a real looker. It could carry up to 44 passengers at an altitude of 40,000 feet. Ground-breaking stuff.

It entered service with BOAC in 1952 and was an instant hit with the passengers who enjoyed superb views from its large square windows…and therein lay the problem, for in 1954 all Comets were grounded after a series of crashes. The thin metal skin became fatigued with the force of repeated cabin pressurisation and depressurisation, and fatigue concentrated around the weak points at the corners of the square windows; cracking resulted in catastrophic failure.

Some success was later enjoyed with the Comet 4 with a redesigned fuselage and oval windows. The exhibit we entered was the fuselage of the first Comet 1A airliner built at Hatfield in 1953 for Air France and is the only remaining fuselage with the square windows.

If you need more, then do visit this gem in the fields of Hertfordshire, you won’t be disappointed.

And finally, in keeping with the aeronautical theme, we met for breakfast at North Weald Aerodrome where coincidentally an American Classic Car meet was taking place – check out the ’62 Thunderbird!

Neil Shanley