When is a moth a better moth? When its made of metal…. August 3, 2009
Posted by shortfinals in Aviation, Great Vintage Flying Weekend, Royal Air Force, aircraft.Tags: ADC Aircraft, aero clubs, aircraft, Aviation, Cirrus engine, Danish register, De Havilland, DeH Gipsy I, DeH Gipsy II, Denmark, DH60, DH60 Moth, DH60M, DH60T, DH82a Tiger Moth, differential ailerons, First World War, flying schools, French, Geoffrey De Havilland, Great Vintage Flying Weekend, GVFWE, Major Frank Halford, Metal Moth, RAF, Renault V-8 engine, Roy Palmer, Royal Air Force, WW1
add a comment
Geoffrey de Havilland’s line of biplane sports/training aircraft, which culminated in the DH82 Tiger Moth, began with the first flight of the DH.60 Moth prototype, at the hands of De Havilland himself, in February 1925. That aircraft, G-EBKT, was powered by a rather unusual engine, built by ADC Aircraft – the Cirrus. This consisted, essentially, of one half of a surplus WW1 Renault V-8 engine, and was, therefore, incredibly cheap. The Moth quickly established itself as the prefered equipment for flying schools and aero clubs everywhere. The Moth was so ubiquitous that soon any light aircraft was refered to as a ‘Moth’.
By 1927, De Havilland had a problem; the huge ‘pile’ of WW1 Renault engines had almost run out, and a new engine for the Moth line was needed. In conjunction with Major Frank Halford, a four cylinder, 100hp engine was designed and built for the DH60; the DeH Gipsy I.
The aircraft you can see is a DH60M Moth, built in 1929. Powered by a DeH Gipsy II of 120hp, it represents the state-of-the-art in light aeroplane design for this period. Several significant changes had been made to the original DH60, including the use of a metal tube primary structure for the fuselage, as opposed to wood (hence the ‘M’ for ‘Metal Moth’). If you look closely, you can still see that De Havilland has retained his ‘differential ailerons’ on the lower wing only, and the wings and tail are in the traditional ‘any colour so long as it is silver’ factory finish (the aero club, or individual customer, chose the fuselage colour). This fine example of the breed is seen here at GVFWE 2009, at Kemble, and is now owned by Mr Roy Palmer; it was on the Danish register, prior to being recovered to Britain.
As well as examples for the civilian market, the DH60 (as the DH60T) was sold to various military customers. The Royal Air Force was not totally convinced, however, and it wasn’t until the sweep of the wings were altered, to enable pilots to bail-out easier in an emergency, and an inverted version of the Gipsy engine fitted, that it finally adopted the Moth as the DH82a Tiger Moth. The rest, as they say, is history.
Air Speed Indicator – the root of it all March 9, 2009
Posted by shortfinals in Aviation, Great Vintage Flying Weekend, aircraft.Tags: 20th century, air speed indicator, aircraft, aircrew, airliner, Airspeed, altitude, ambient pressure, analogue, ASI, atmospheric conditions, Aviation, back-up, basic six, bulkhead, cockpit, commercial airliner, De Havilland, dead reckoning, DH 84, DH 85, digital sensors, Dragon, electric torch, end plate, flaps, flight envelope, French, French enginer, fuselage, G-AIYS, glass cockpit, graduated scale, GVFWE, Henri Pitot, Keevil, Leopard Moth, never exceed speed, night flying equipment, pilot, pitot tube, port, ram-air pressure, Royal Air Force, spring wire, stall, stalling speed, static pressure, stick and string aircraft, undercarriage
add a comment
Air Speed Indicator!
Every since the first fragile ’stick and string’ aircraft staggered into the sky during the first years of the 20th century, the pilot has needed to know just how fast he is going. Not only because he uses this value to help him determine his position by ‘dead reckoning’ (time x speed = distance run), but also when he is entering dangerous areas of the ‘flight envelope’ of his aircraft. Being close to the stalling speed of the machine is lethal, but also there is a ‘never exceed speed’, above which lies structural failure. There are various other speeds which it is important to know, such as the safe speed at which flaps may be deployed, or the speed at which the undercarriage must not be extended (if retracted, of course).
Modern aircraft often have a ‘glass cockpit’ display which gives readouts of airspeed from digital sensors, but even these have an old-style analogue dial, as a back-up. The usual two inputs needed to produce an ASI readout are the static and ram-air pressures, one being the ambient pressure (which changes with altitude and atmospheric conditions) and the other being the pressure due to the aircraft’s movement through the air. These are usually obtained from a Pitot tube (named after the French engineer, Henri Pitot), located a little distance from the fuselage, to avoid air disturbances. The ASI became part of the ‘basic six’ instruments ,which were instantly recognizable by any Royal Air Force aircrew member from the 1930s onwards
Up until the mid-1930s there was another method – crude but adequate – used in some low-performance machines. Here we see a photograph of the air speed indicator on a DH 85 Leopard Moth , G-AIYS, parked at GVFWE, Keevil. All it consists of is a flat plate, with a few holes drilled in it, secured to a length of spring wire. As the air pressure builds up due to movement of the aircraft, the plate is forced backwards, giving a readout of the estimated speed on the graduated scale. There is even a red section, indicating when you are approaching the stall! Needless to say, this device IS crude, but it works well enough. The Leopard Moth’s bigger brother, the De Havilland DH 84 Dragon airliner has a similar indicator, and I dare say that this was the last time a commecial airliner flew with such a device. By the way, the first time I entered the cockpit of a DH 84 Dragon, I noticed an electric torch clamped to the left hand side of the bulkhead. When I asked what it was, I was told that it was an essential piece of the night-flying equipment….at night, you shone it out to port, and illuminated the graduated scale between the wings to find out your airspeed!
The rare made commonplace – G-AIYS, DH 85 Leopard Moth March 6, 2009
Posted by shortfinals in Aviation, Great Vintage Flying Weekend, Museums, Royal Air Force, Second World War, aircraft.Tags: aeronautical engineer, Air Show, aircraft, aircraft disposal sales, airfield, Aston Martin, Baghdad, Biggin Hill, communications aircraft, De H 85, De Havilland, De Havilland Gipsy Major 1 engine, DH 80, Egypt, England, fabric-covered, folding wings, Geoffrey De Havilland, Gipsy Major engine, Great Vintage Flying Weekend, GVFWE, hangarage, impressed aircraft, Iraq, Keevil, King's Cup Air Race, Leopard Moth, liaison type, Mr Ronald Gammons, Mrs Valery Gammons, oil companies, plywood, prototype, Puss Moth, RAF, RAF Kemble, RAF Museum, Scotland, Second World War, Sir William James Denby Roberts, steel tube, Strathallan Collection, Surrey and Kent Flying Club, Torquil Norman, Victor Guantlett, Wiltshire, WW2
add a comment
- The rare made commonplace – De Havilland DH 85 Leopard Moth
Geoffrey De Havilland was a skilled aeronautical engineer, of that there was no doubt, but he was also a passionate lepidopterist, and named many of his early creations after various species of moth. The Leopard Moth was designed in the 1930s to provide a relatively swift (c. 130 mph) ‘gentleman’s aerial carriage’ (one pilot, two passengers). The prototype won the King’s Cup Air Race in 1933 at over 139 mph, flown by Geoffrey De Havilland himself. The fact that De Havilland had forsaken the fabric-covered steel tube formula of the Leopard Moth’s predecessor, the DH 80 Puss Moth, and instead built a strong, sturdy ‘box’ from plywood, giving a structure of lower weight, enabled the aircraft to fly faster and further. The DH Gipsy Major 1C engine puts out around 142 hp, which gives a cruise speed close to 120mph, and a range of over 700 miles.
A faster dragon………… February 20, 2009
Posted by shortfinals in 'warbird', Aviation, RAF, Royal Air Force, Second World War, aircraft.Tags: 'Valkyrie', 'warbird', 621 VGS, air ambulance, Air Atlantique, Air Atlantique Historic Flight, Air Show, aircraft, airliner, Aviation, Brush Coachworks, communications aircraft, crew trainers, Culham, De Havilland, De Havilland Major Six engine, DH 80A, DH 84 Dragon, DH 89A Dragon Rapide, DH Gipsy Queen 3 engine, Dominie T.1, Dragon Rapide, Dragon Six, Duxford, Edward Hillman, Fairey Reed propeller, G-ATGM, glider, GVFWE, hangar, HMS Hornbill, Hullavington, Imperial War Museum, Iraq, Iraq Transport Company, Jordan, JY-ACL, Leicestershire, light bomber, Lithuania, Loughborough, Mike Russell, NF875, Oxfordshire, Parachute Regiment, Puss Moth, RAF, RNAS Culham, Royal Air Force, Royal Naval Air Station, Royal Navy, Russavia, scheduled airline, Second World War, Spanish Civil War, Viking T Mk 1, Volunteer Gliding Squadron, Wiltshire, WW2
add a comment
- A faster dragon…..
Edward Hillman had built a economical charter and scheduled airline business using the safe, affordable De Havilland DeH 84 Dragon – the Dragon had arisen because Hillman’s DeH 80A Puss Moth wasn’t big enough, and he negotiated with the company for a ‘twin-engined Puss Moth’. What he needed now, in the late 1930s was a ‘faster Dragon’. Enter the Dragon Six (sometimes called the Dragon Rapide, and later just Rapide) with its Gipsy Major 6 engines of 200hp, and capable of carrying eight passengers, it was an instant success in the civil market. There was military interest too, with light bomber varients being used during the Spanish Civil War, and sold to smaller nations such as Lithuania. The Royal Air Force needed radio and crew trainers, as well as communications and air ambulance machines. The Dragon Rapide put on ‘warpaint’ and became the Dominie T.1, the vast majority of them being built by Brush Coachworks, at Loughborough in Leicestershire. G-AGTM was one of these, built in 1944 and originally bearing the RAF serial NF875.
G-AMMS, not an Alpha, but alphabet soup again! February 16, 2009
Posted by shortfinals in Aviation, England, Great Vintage Flying Weekend, aircraft.Tags: aerobatic, Auster, Auster Aiglet Trainer, Auster Aircraft Ltd, Auster J-1N Alpha, Aviation, Blackburn, Blackburn Cirrus Major 3 engine, Cirrus Major, De Havilland, De Havilland Gipsy Major 1 engine, England, Fairey Reed, G-AMMS, Gipsy Major engine, GVFWE, Hullavington, J5F, J5K, J5L, Leicestershire, metal propeller, Pakistan, Pakistan Air Force, Rearsby
2 comments
- G-AMMS
Sorry about the terrible Auster pun at the start of the post, but I could not resist this opportunity. G-AMMS isn’t an Auster J-1N Alpha, of course, but a much changed Aiglet Trainer. Built in 1951 by Auster Aircraft Ltd at Rearsby, it was retained by the company until 1954, being completed as a J5F, then modifed as a J5K (the only such aircraft) and J5L. The airframe was fitted, at various times, with a De Havilland Gipsy Major 1 of 130hp or a Blackburn Cirrus Major 3 of 155hp, and had the Auster Aiglet Trainer’s shortened wingspan (from 36 ft to 32 ft, to increase the aircraft’s roll rate) and strengthened structure to enable aerobatics to be performed. Aiglet Trainers were popular abroad, and the Pakistan Air Force used them in quantity.
Percival Prentice vs De H Chipmunk…and the winner is… January 24, 2009
Posted by shortfinals in Aviation, British Isles, RAF, Royal Air Force, aircraft.Tags: 'warbird', ab initio trainer, aircraft, Aviation, Aviation Traders Ltd, Chipmunk, Coventry, De Havilland, Freddy Laker, Gipsy Queen engine, L hangar, Percival, Percival Prentice, RAF, Royal Air Force
add a comment
Percival Prentice T.1
The Percival Prentice T.I was a direct contemporary of the De H Chipmunk in RAF service. Both of them were used as ab initio trainers, but there really was no contest, in many respects. The Prentice first flew in 1946, entering service in 1947, but all three hundred plus aircraft were withdrawn by 1953. Many of these aircraft were bought by Aviation Traders Ltd (the brainchild of Freddie Laker) and an attempt was made to convert them to four-seat touring aircraft – they were not a success. Powered by a 251 hp De H Gipsy Queen Six engine, this relatively large aircraft had marginal performance under some conditions (especially ‘hot and high’). There was also a history of difficult handling, including poor spin recovery, hence the sharp dihedral of the wingtips.
VR259 is shown hangared in one of the L-type hangars at Hullavington, although it usually is to be found at Coventry, the home of Air Atlantique.
In contrast the ‘Chippie’ looks elegant and a picture of efficient design. There are only five Prentices on the British register – dozens and dozens of Chipmunks!
A beautiful Chipmunk
Lining up for departure January 20, 2009
Posted by shortfinals in Aviation, Great Vintage Flying Weekend, aircraft.Tags: Air Unique, aircraft, An-2, Antonov, Aviation, De Havilland, DeH 85, Empire Test Pilots' School, Gipsy Major engine, GVFWE, Hullavington, Leopard Moth, Mr & Mrs Gammons, RAF, Scottish Aviation, Twin Pioneer, Wiltshire
add a comment
- An-2, Twin Pioneer, Leopard Moth
Sometimes the line-up for departure at the end of each day of a Great Vintage Flying Weekend can get rather interesting. Here we can see Air Unique’s An-2 ‘Baltic Bear’, in front of Air Atlantique’s Scottish Aviation Twin Pioneer in Empire Test Pilots’ School livery getting ready for departure from Hullavington, Wiltshire. The De Havilland DeH 85 Leopard Moth in the background belongs to Mr and Mrs Gammons, and is kept in beautiful working order. It was built in 1934, and its Gipsy Major 1c has kept it flying for more than 3,300 hours, a distance in excess of 400,000 miles – or 15 times around the Earth!
‘Tyger! Tyger! Burning bright….’ January 2, 2009
Posted by shortfinals in Aviation, Great Vintage Flying Weekend, RAF, Royal Air Force, aircraft.Tags: aircraft, Aviation, De Havilland, Gipsy Major engine, GVFWE, RAF, Royal Air Force, Thruxton Jackaroo, Tiger Moth
add a comment
De Havilland 82A Tiger Moth II
De Havilland DeH 87B Hornet Moth, GVFWE, Keevil, 2006 December 4, 2008
Posted by shortfinals in Aviation, Great Vintage Flying Weekend.Tags: Aviation, De Havilland, Great Vintage Flying Weekend, Hornet Moth, RAF, Royal Air Force
add a comment
DeH 87b Hornet Moth, GVFWE 2006, Keevil
GVFWE ‘06 at Keevil was a little difficult to stage, as the grass surface was rather uneven in places. Visually it was an interesting setting though, and despite high winds and rain during the ’set-up’ phase, it attracted a wide range of vintage and veteran aircraft. Here you can see a superb example of the DeH 87B Hornet Moth, this one in wartime camouflage. Keevil was used by the USAAF on D-Day, and C-47 aircraft left from here on the night of June 5/6th, 1944, to drop paratroopers over DZs in Normandy.
