Tinworm-wings: Hang Glider speedo

Thursday 29 January 2009

Hang Glider speedo

At Sywell the other day I brought up the subject of making your own instruments and Stewart mentioned a simple ASI which hang glider pilots have used for years and which sounded elegantly simple. It is called a Hall Airspeed Indicator, and at $23 it costs about an eighth of a Digifly probe (which then needs to be connected to a vario costing another £164!) Put a different way, by getting one of these I can save myself about £230! (though the Digifly has several other desirable functions, like an altimeter - which is something I will still need to get)

Essentially the Hall ASI is a tube with a disc inside it which is raised up a graduated (colour coded) scale by air flowing in through the bottom. The disc is kept upright by a central spindle. Read the link to learn about the colour bands.

I love the fact that SSDR provides the creative pilot with the opportunity to experiment with technologies from other fields. I like the open-minded cross-over between paragliding, hang gliding, etc which is a particular strength of the team at Flylight, who have lots of experience of all aircraft types, from hang gliders and paragliders to Pitts Specials; electric motors, twin engines to jets; parachutes to two axis, flex wing and fixed. They are a versatile bunch.

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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!