The proving of the Moth
The De Havilland Moth biplane was undoubtedly the most successful light aeroplane of its era, notwithstanding a number of others, which can he listed as the Avro Avian, the Blackburn Bluebird, the Simmonds Spartan, the Robinson Redwing, the Parnell Imp and the Southern Martlet, if we confine the list to biplanes of the period. Last July I took you briefly through the fascinating but futile Light Aeroplane Trials at Lympne in the first year (1923) of their institution by the Air Ministry (its foresight overshadowed, as it happened, by the ever-air-minded Daily Mail). These trials proved two things. First, that a 750 c.c. engine (and later an 1,100 c.c. power unit) was unsuited to serious flying of even an amateur status, even for the pilot on his own (and equally, for two, with the subsequent enlarged engine stipulation). Secondly that motorcycle engines, even if slightly modified, were too unreliable for serious consideration in aeroplanes (and that the special 1,100 c.c. power units designed for the 1924 Lympne two-seaters were still too low-powered. at around 35 h.p., for requirements).
It was for these reasons that Geoffrey de Havilland produced the now immortal DH60 Moth. He was convinced that at least 50 h.p. was needed to power a practical school or touring two-seater light aeroplane, to give a cruising speed of 80 m.p.h. and a three-hour flying range. Making good use of Major Frank Halford’s engineering expertise (he of the Halford Special racing car) in adapting unwanted war-surplus Renault V8 seen-engine parts for a new four-cylinder air-cooled in-line 60 h.p. ADC-Cirrus I engine, Capt. de Havilland ignored the 1924 and 1925 Air Ministry Lympne contests and got on with producing his new light aeroplane at the same time as Major Halford was evolving his engine for it — the latter apparently needing but nine weeks to put one cylinder bank of the Renault engine onto a new crankcase, with wet sump, retaining the cylinders and exposed push-rod oh-valve gear.
On February 22nd, 1925 the prototype DH Moth (G-EBKT) was ready for testing — I was 12 years old that day and although memory is blank, expect I read of it with interest in the newspapers. Capt. de Havilland went up by himself in the new Moth from Stag Lane, Edgware, and finding everything in order, landed to pick up Capt. Broad and try again with a passenger. Again all was well and a top speed of 90 m.p.h. was spoken of which was beyond estimations.
So here was the first truly practical two-seater light aeroplane. It had a wingspan of 30 ft. and weighed 770 lb. empty, being, in fact, virtually a scaled-down DH51, of seven foot shorter wing span. The Moth’s wings folded for easy storage (in the home garage?) and it sold for £885, reduced to £795 by August 1926, equivalent at the time to buying. say, a Lancia Lambda Weymann saloon, a 19.6 h.p. Crossley or a straight-eight Bugatti with something in hand. Soon afterwards the faster Cirrus II Moth was priced at £730, from its original price of £830. Success was assured and in spite of a small flood of similar biplanes, some like the Avro Avian, rather less expensive, it was the De Havilland Company that reaped the richest reward in this newly-released civilian field. In this it was aided by the dithering of the Government, which would not allow the newly-formed flying schools to use the obsolete, but essentially-safe, Avro 504 for training purposes, so had to give the orders to the De Havilland Company in spite of the snoot the DH60 Moth had cocked at the very light ‘planes the Air Ministry had hoped to encourage with its Lympne competitions.
Before the summer of 1925 was over production Moths had begun robe delivered, and in that first year of production 29 were made, culminating in a total of 1,800 Moths when production ceased in 1934, having continued at Hatfield after the De Havilland Company left Stag Lane, and taking this remarkable little aeroplane through various marks, the later versions powered with the splendid DH Gipsy engine, which the Company were happy resell to makers of rival light ‘planes. And ironically, when the AM Light Aeroplane Competitions persisted into 1926, with the old engine-size stipulations replaced by weight-limits, Capt. Broad’s 75 h.p. Genet-powered DH Moth took 3rd place, behind the Hawker Cygnet and the Supermarine Sparrow II. It is even more ironical that, although a book has been written about the DH Tiger Moth, there isn’t, as far as I know, one devoted entirely to the DH60 Cirrus and Gipsy Moths, although this is largely made up for by the excellent coverage of this most famous of light aeroplanes in Terrance Broughton’s book “The Story Of The British Light Aeroplane” (John Murray, 1963). So, rather than delve into details of the Moth itself, let us look at how its abilities were proved, in those early years of private aviation.
Some three months after the Moth’s introduction, Sir Alan Cobham flew the prototype G-EBKT from Croydon to Zurich and back, in a time of 6 hours 6 min,. for the outward journey, and 7 hours 45 min. for the return flight against a head wind, for the 1,000 miles. The 4½-litre engine apparently gave not a moment’s anxiety and the average speed was over 70 m.p.h. at approx 17.8 m.p.g. of petrol (about the same as a vintage sports-car of similar engine size, and just over 70 m.p.p. of oil_. This was an excellent first proving-flight for the new Moth, although it must not be forgotten that in 1920 Bert Hinkler had flown the 35 h.p. Avro Baby from Croydon to Turin in 9 hours on a leisurely flight, going on to Rome, where his intention of continuing to Australia was frustrated by the Authorities.
Within the British Isles the Moth did some impressive flying in the first year of its existence, when, just before Christmas 1925, Colonel the Master of Semphill flew one from Stag Lane to Dublin across the 70 miles of sea from Holyhead and, sheer tour of the Irish Free State, returned in foggy weather by the shorter Stranraer route, landing on a mud bank near Lancaster to refuel with tins of petrol carried in the Moth’s locker— true private-venture flying, As a result, the Irish Free State Government ordered four OH Moths, which were also flown to Dublin.
Moths also performed some useful flying during the General Strike of 1926. But the first of the truly epic flights undertaken in these machines, which were incredibly frail by today’s constructional standards, was made in 1926/27, when Capt. Neville Stack, an Instructor at the Lancashire Aero Club, persuaded a pupil, Bernard Lecte, to accompany him on a touring flight to India, Stack taking with him his ukelele to pass the time on the ground. Little money was available but Stack persuaded De Havilland’s to sell them two 85 h.p. Cirrus 11 Moths, G-EBMO, painted white (which had won the 1926 King’s Cup race at 90.5 m.p.h.), and G-EBKU, painted blue, which was the second Moth built, BP agreed to supply the modest 128 gallons of Anglo-Persian aviation spirit. These two second-hand Moths, with new Cirrus II engines, cost £1,200 the pair, including a 20 gallon extra fuel tank and a spare propeller for each machine. Leete was able to draw the money from the family trust. Beyond Rome they set up new records for light ‘planes for the 5,540-mile journey, as none had assayed the route previously.
Both Moths were serviced by the RAF in Iraq, and fuel stops were planned at Bushire, Bandar, Abbas and Charbar. The only trouble was when ‘KU lost revs some 45 minutes out from Bushire, and had to come down at an emergency landing ground at the desert to let the oil cool off. After flying on to Bushire, Wakefield’s were contacted by telephone and they suggested draining off the Castrol R and refilling with Castrol X. This restored compression for the 450 mile flight to Bandar Abbas, which took less than seven hours.
The route through Bushire, Bandar Abbas and Charbar was chosen because Imperial Airways were prospecting the air-mail run to India. In fact, the DH 66 Hercules air liner carrying Sir Samuel and Lady Hoare was encountered en route. Incidentally, Leete decided to remain in India, to help start flying clubs there, at which he was Chief Instructor, and during the war he became a Sqdn.-Ldr., being awarded the OBE and AFC, until blinded in a glider accident; he died in 1978 after writing a most interesting account about the India flight and his years in India during the time of the British Raj, a book which awaits a publisher.
As Moth production increased and improvements were made, those little aeroplanes accomplished other “proving achievements”. The 1927 King’s Cup race was won by W. L. Hope’s Cirrus I Moth, at 92.8 m.p.h., Lady Bailey flew hers to a record height of 17,283 feet over Stag Lane (improved to 18,800 feet over Croydon in 1928 by Lady Heath, in a 90 h.p. Cirrus III Moth, and some notable long-distance touring-flights were successfully made. These included Lt. Bentley’s two return trips, Croydon-Cape Town-Croydon, Lady Bailey’s 18,000-tithe trip to and around South Africa, and Lt.-Comdr. MacDonald’s flight to Baghdad after going solo for only eight hours. Other pilots flew the later 90 h.p. Moths out to Kano, to the Gold Coast, etc., and the Gipsy Moth continued the good work in racing in the 1928 King’s Cup race, which Hope won at 105 m.p.h.
Capt. de Havilland, and wife, set a 21,000 ft. altitude record in his own Moth (G-AAAA), Capt. Broad, taking aloft books to read, flew G-EBYK for 24 hours non-stop over Stag Lane, and a Gipsy I Moth. taken at random from the DH production shops, flew an officially-observed 600 hours (51,000 miles) after which engine servicing cost a were £7/2/11 — shades of the Rolls-Royce Silver Ghost’s 15,000-mile endurance test of 1907. Indeed, long-distance Moth flights were by then legion, even to a fatal cross-Atlantic bid. Pure record-breaking was soon to follow.
Than Amy Johnson in “Jason” got from Croydon to Darwin in 19 days in 1930, the first woman to do so solo, having flown only 150 miles over England on her longest flight beforehand, although beaten on time by Hinkler’s Avro Avian. (I have always wondered, however, how the repairs made to the Moth after it landed heavily, Including a new wing provided by the RAF at Singapore rated, in record-claim terms.) Francis Chichester took five weeks, then put floats on his Moth for the epic navigational flight back from New Zealand to which his machine had been shipped from Australia. Space does not permit reference to all the record flights by DH Moths that followed, and which made the vintage years of aviation so entrancing — especially if, as I did, you went to Croydon to see the adventuring heroes return. Pilots of the calibre (and in this context, what a lot of fine qualities that word implies!) of O. Garden, C. W. A. Scott, Jun Mollison, Jean Batten and Grierson broke long-distance records in the famous light plane, before the Puss Moth and Leopard Moth monoplanes took over.
Jean Batten, on her third attempt, did Australia from England in 1934, in 14 days 23 hours, in a Gipsy I Moth, getting back in 1935 in 17 days, 15 hr. 15 min., after her engine had cut out over the Timor Sea, the Moth losing height from 6,000 ft. to nearly zero ft. before it picked up again. This was the first England-Australia-England solo flight by a woman, which Amy Johnson had hoped to achieve. By then the Moth was out of production. But it had definitely established its worth, in what we now call “the vintage years”. By 1928 its price had fallen to £630. Several racing drivers owned Moths, including Sir Malcolm Campbell (G-ACMY — actually a Moth Major) and R. O. Shuttleworth (G-EBWD, which is still in the Shuttleworth Collection). Today “Moth” seems inevitably to imply a Tiger Moth, but let us spare a thought for the greatest of all the light biplanes, the genuine DH Moth of the period 1925-34. — W.B.
NB: I had intended to describe some of these epic Moth flights in more detail, but in a motoring paper space does not permit. I can, however, recommend such books as “Amy Johnson” by Constance Babington Smith (Collins, 1967), “Alone In The Sky” by Jean Batten (Airlife, 1979), and “The Sky’s The Limit — Women Pioneers in Aviation” by Wendy Rouse (Osprey, 1979) for an understanding of the risks and the atmosphere of flying the brave little DH Moth long distances in the vintage days. — W.B.