Tinworm-wings: An SSDR Flying Flea?

Sunday, 6 July 2008

An SSDR Flying Flea?

Mignet in a later model

In the 1980s I fell in love with the Flying Flea. An old geezer in a pub told me that he knew of one in someone's loft and I was intrigued. I never did find the Flea in question, but it got me reading about them and I got a translation of Henri Mignet's 1934 book, Le Sport de L'Air in which the aeroplane's designer shares his philosophy and describes the process for constructing one.

The cut-away drawing was produced by "The Aeroplane" and three issues of 1935's Newnes Practical Mechanics showed people how to build the Flea. Mignet, an amateur who had been turned down for the French air force and who said that he had found conventional aeroplane controls illogical and counter-intuitive, designed his aeroplane to be easily mastered by a novice and built by anyone capable of constructing a packing-case.

Mignet was a 1930s microlighter! Modern microlighters ought to find his articulated wing intriguing because like the weightshift's, the whole wing pitches, while as with any other 3-axis, yaw is down to the rudder. I am not quite certain about roll, but I believe it was induced by a combination of the leading wing and the rudder. Strictly speaking I suppose it is a 2-axis rather than 3-axis aeroplane.

an amateur builder/flyer in his original model HM-14

Numerous enthusiasts did build the Flea but there was a spate of crashes which got the type grounded by the Air Ministry here while the Royal Aircraft Establishment wind-tunnel tested the type to work out why it kept crashing (film of Mignet, and Mr Appleby crashing). In 1990 I pored over and annotated RAe notes to try and grasp what had gone wrong.

I wanted to understand because I had a hankering to build the version of aeroplane Mignet went on to design, which would apply the modifications recommended by the RAe. My recollection is that the staggered wings were too close together and that they were not acting independently, so that once in a dive, it was impossible to recover...even if you were an experienced pilot. I think the wings had to be more widely spaced. A more conventional, rounded leading edge was suggested to replace Mignet's sharp edge and I think the centre of gravity was moved.

Mignet also added control struts to make the rear wing "conjugate", but the bad publicity meant that even when the ban was lifted, few people had any faith in Fleas. Mignet did carry on building his designs and I think they are still popular in the USA, where there is a far more liberal attitude towards experimental aircraft.

Luckily I went no further with my plans at the time. The fact is that while I could have built a very respectable packing-case, I am confident I would have built a death-trap if I had then attempted a Flea. That was before I studied industrial design or knew anything really about engineering.

A few days ago I saw in the 2001 edition of World Directory of Leisure Aviation that there is someone selling plans for a Pou Bébé with an empty weight of 110kg and it got me thinking. Could a Flying Flea be built by an amateur and flown as a de-regulated microlight?

See wikipedia about the Flying Flea

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The photo below is of a paper model I made of the Flea from a design at Fiddlers Green (an American paper modelling site). There is no need to pay for the model if you would like a copy. Chip won't mind me sharing it with enthusiasts; he is very generous that way.

Just email me for a copy.

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Ground handling (how to store an aeroplane at home and get it to the airfield)

A trial flight in a Thruster, when I was 28, c.1991

I have started to learn to fly before...TWICE! First time round I had just graduated and got a job at an aerodrome in Cornwall, where I earned flying hours by fuelling microlights, giving hourly weather reports to the Met office etc. The weather was bad, so there was little flying to be had...and in the end I was paid with broken propellers and bits of crashed fuselage to hang on the wall. The boss was a great bloke called Ian Stokes, who had been a leading light in forming the BMAA and had manufactured Thrusters in the early days . In retirement he moved to The Gambia and became a publican and, shockingly, was murdered this year.

Flying Rogues

ten years on from my first experiences at Moorland Flying School (and now nearly ten years ago) the flying school was under new management and my girlfriend and I booked full courses. We both made good progress initially but never felt we were being moved on and had difficulty pinning the instructor down to signing our logbooks. When another instructor signed himself as P1, we got suspicious, contacted the CAA and were horrified to learn that our instructor did not have a current instructor rating, that we had not been insured and that none of our hours counted towards our licences. We were eventually refunded and the instructors were prosecuted by the CAA.

The very sympathetic CAA investigator spoke to the BMAA on our behalf and my hours have been allowed to count (at the discretion of the school). But in point of fact, I flew way over the minimum number of hours subsequently, so it is really quite academic in the end.

Around 2001 an instructor in Norfolk tried to convince me that if I bought his aeroplane he could teach me at a cut rate, as I'd then be using my own plane. Great idea, I thought, except that it turned out that the aircraft in question had failed a noise test and could not be used from the instructor's field. He later admitted that I would have to learn on his aeroplane at the normal rate. He resisted showing me the paperwork, kept avoiding me and eventually, when it was quite clear I wasn't going to buy without the paperwork, told me to F-off.

So far my experience has been that there are a lot of rogues in flying, which is one reason why I was so very impressed by the professional set-up at Sywell.

by air to Africa

My sister and I were lucky to fly many thousands of miles in the 1960s and '70s in many aircraft types, including BOAC VC-10s, Boeing 707s and even a Nigerian Airways Dakota, as our dad (and later our mum) had teaching posts in Kenya and Nigeria. Those were still the romantic days of flying, when passengers walked across tarmac and up steps, rather than walking down the tubes that have turned passenger flying into a mundane affair. (Mind you, aren't take-offs still incredibly exciting!?)

Back then air hostesses GAVE children the sorts of nick-nacks that their parents have to pay fortunes for from the airline catalogue these days; things like model aeroplanes, keyrings etc. We were also given sweets to help us cope with depressurisation. (And they were hostesses, so nobody give me a hard time)

Mum says that I cracked my first joke when I was small, on a flight out to Kenya, when I said, "Mummy, shouldn't there be a wing on this side of the plane too". Apparently I got her with that one.

At Kano airport I remember standing behind an engine and thinking how hot it still was....and then being told that the engine was cold. The heat was Kano. I got a headache and took several days to aclimatise.

The airport perri-ways at Kano were littered with aircraft that didn't make it, including a burnt-out Mig 15. The Nigerian Airforce flew them and my dad played squash with one of their pilots, Ben, at the Kano Club. I recall a Mig fly-past on my birthday. Was it arranged with Ben over a beer? Was it a pure coincidence?

At Entebbe airport (Uganda) I remember climbing down the steps on to the runway and being encircled by soldiers with machine guns, who then went through all our belongings and confiscated my cherished Swiss Army penknife, purchased on one of numerous European stop-overs. That was in the twitchy time after the Israeli hijacking ...and mum had to stifle my protests.

Before my first flight to Nairobi, as an infant, I was scared stiff. I didn't understand that I wouldn't have to sit astride the fuselage, as I did on my pedalcar! In a funny way, I not only overcame that fear but have come full circle; microlighting is just like sitting on that pedalcar......open to the elements - real flying!