See also Guy Gratton's article here

Microlights – A Very Rough Guide
by Simon Newton

Microlight? Wassat?

Well, legally a microlight aircraft is a category of aeroplane that:

• has a maximum take-off weight not exceeding 450kg (300kg for single-seat aircraft); and
• has either a wing loading not exceeding 25kg per square metre, OR a stalling speed of not more than 65kph (about 40mph or 35kt); and
• can carry a maximum of 2 people.

Microlights operated in the UK must be designed and constructed to satisfy the British Civil Airworthiness Requirements, Section S – arguably one of the toughest microlight/ultralight airworthiness standards in the world (see www.caa.co.uk/docs/33/CAP482.PDF) for the gory details). The CAA delegates the regulation, inspection and approval of microlight aircraft in the UK to the British Microlight Aircraft Association. [Note - microlights can be operated through membership of the Light Aircraft Association, but the majority are not and I have no experience of this route of operation. See the LAA (www.lightaircraftassociation.co.uk) for more details if required]. New microlight aircraft can be bought ready-to-fly from a CAA approved manufacturer or can be built from an approved kit under technical supervision (similar to the process for kit-built light aircraft). There is also, of course, a thriving market in used aircraft.

Irrespective of age, source or construction method all microlight aircraft must be checked annually by a BMAA-approved Inspector to ensure that they are airworthy and safe, to include a test flight by an appropriately qualified person. After a successful test the aircraft's Permit to Fly will be validated for a further 12 months by the BMAA on behalf of the CAA. For more on Permits and what it means for owning and operating an aircraft see later.

The two main types of microlight operating in the UK are the flexwing and fixed wing varieties.

Flexwing:

Also known as trikes or weightshift aircraft, these are what many people think of when you mention “microlights”. Using a delta-shaped wing (or 'sail') reminiscent of that of a hang-glider, these aircraft have a trike unit suspended underneath for pilot, fuel tank, engine and undercarriage – and dependent on type and price may have a second tandem seat, aerodynamic pods, screens, fairings and luggage panniers. All flexwings currently flying in the UK are open cockpit which means helmets are essential, as well as good warm specialist clothing. Flexwings use the pendulum effect of the suspended trike unit to manoeuvre by shifting the weight from side to side and front to back. Flown solo from the front seat on two-seaters, a triangular control bar is positioned in front of the pilot and in the air to initiate a bank to the left, for example, the pilot moves the bar to the right. This actually shifts the weight of the trike over to the left, causing the bank. Similarly, to pitch the nose up the bar is pushed away from the pilot, shifting the trike backwards and causing the sail to angle upwards. Most trikes are equipped with a foot-operated throttle as well as a hand operated one to allow for both hands on the bar during take-off and landing.

Flexwings come to suit every budget and every performance requirement. There are plenty of vintage, single-seat aircraft using very small two-stroke engines really suitable only for use on calm summer evenings, bimbling along at 40kt or less, yours second-hand for a couple of thousand pounds. The latest generation of factory-built aircraft can fly at 100mph using 100hp four-stroke engines, have electric trim, impressive avionics fits, and advanced aerodynamics including winglets to reduce vortices, and have good rough air handling - brand new you'll not have much change from £25,000. There is a thriving market for new and second-hand models that span the range between.

What are they like to fly? “Like flying a motorbike” I'm often told, and having been a back seat passenger a couple of times I can vouch for that. I can recommend the views from a flexwing - the narrow trike unit and tandem seating means you've got excellent line of sight all round and especially down over the side. The climb rate on take-off is great even on the more modest types, but the climb angle is lunatic – if that doesn't give you a grin, nothing will. As for landings, general form seems to be stay pretty high until you’re just behind the numbers, reduce the throttle and about 50 metres later it appears you’re on the ground and stopped! Power off the sink rate is impressive, so keeping high on final is a good thing. I’d be hard pressed to think of a better aircraft to be in for a warm summer’s evening bimble over some glorious countryside. It’s not going to be everyone’s cup of tea, and certainly in colder weather you need to be extremely well-insulated and not mind sitting exposed to the elements, but I think it’s a type of flying everyone should try at least once.

Fixed wing:

Also known as three-axis aircraft, these adopt the more “conventional” aerodynamic surfaces and controls: aerofoil wings, conventional tail surfaces, ailerons, elevators and rudder (flaps are also fitted to some types). Flying is by “stick and rudder” and the controls all work in the same way as they do in light aircraft – the difference is the wide variety of types and styles to choose from. Front and back propeller configurations, 'rag and tube' (sail cloth and aluminium alloy) construction or all-metal or increasingly composite, open or closed cockpit, taildragger or nosewheel (or even interchangeable), high- or low-wing or even biplane, tandem or side-by-side seating… the list goes on. Some of the more recent designs look almost indistinguishable to traditional light aircraft to the uninitiated, and some of the older and more unusual look like nothing else you’ve seen!

There has been an increase in interest in fixed wing microlights in recent years, mainly due to an influx of eastern European aircraft that are able to offer (sometimes better than) light aircraft performance with much reduced running costs. Some of the most recent designs are all-composite “hotships” that can cruise at 100kt plus for four hours in plush heated comfort whilst burning less than 15 litres of fuel an hour. These things will cost you up to £50,000 new. At the other end of the scale you can buy a semi open-cockpit rag and tube tail-dragger aircraft in good condition with a two-stroke engine that dawdles along at 45kt for under £4,000.

Although the speedier (and more expensive) end of the market has become very popular, especially amongst budget-conscious former light aircraft pilots, there is still massive support for the more “seat of the pants” end of the market – but I have to declare an interest as that’s what I fly! I have a four year-old factory-built AX2000 aircraft (one of the last made) with a two-cylinder, four-stroke HKS engine. The roots of its design go back over 20 years, but I can carry two fourteen stone crew, twelve kilos of baggage and full fuel tanks. This will give just under six hours endurance at a cruise of 55kt. There’s no cabin heat, and the wind whistles through the gaps a bit, but it’s still quicker A-to-B than a car and if you’re just up for some fun flying then it fits the bill brilliantly. If you’re used to flying Group A aircraft, why not have a go in a fixed wing microlight? The modern designs will handle as well as, if not better than, most basic club aircraft and as a bonus they tend not to have interiors that look like a tatty 1960s saloon car! The older designs like mine (with its interesting adverse yaw) might just teach you what those rudder pedals are actually for and make you feel a bit more connected to the aircraft. But then I would say that, wouldn’t I!

Flying and Owning a Microlight – Paperwork

Flying:

If you don’t have an existing flying qualification then to fly a microlight you need to follow a course of instruction from a qualified microlight instructor leading to a successful pass of a General Flight Test with an authorised Examiner lasting about an hour and a half. In addition you will need to pass multiple-choice exams in Air Law, Aircraft Technical, Human Performance and Limitations, Aviation Meteorology and Navigation. If you wish to use a radio then you will need to take written and practical tests for that as well. Your training will follow a structured syllabus virtually identical to that of the light aircraft licences and you must complete a minimum of 10 hours of supervised solo flight, to include two qualifying cross-country flights. Once you have all these requirements you will be able to be the proud holder of a National Private Pilot’s Licence (Microlights) or NPPL(M). For full details, including syllabus and medical requirements see www.nppl.uk.com.

For those who already hold a Group A PPL then according to LASORS ["Licensing, Administration and Standardisation, Operating Requirements and Safety", a snappy little title from the CAA - ed. ] and you don’t have too onerous a route to follow to get yourself signed off for solo flight in microlights:

"The holder of a UK/ JAR-FCL licence with valid SEP rating and appropriate JAR-FCL medical certificate may, subject to completion of appropriate differences training, exercise the privileges of the JAR-FCL licence on microlight aeroplanes … in UK airspace only. For microlight privileges this training must be with a microlight instructor…. However, any experience gained in microlight aeroplanes … cannot be counted towards the flying experience requirements to maintain the SEP rating."

If you’re going to fly three-axis then differences training shouldn’t take too long as the control principles are fundamentally no different. If you are going to go the flexwing route then it’s probably going to take a bit more training before your brain clicks into the weight-shifting way of thinking.

If you have an NPPL(SEP) then you will need to add the M rating to your licence. This will involve passing a ground oral exam on type, to include pilot maintenance requirements and conditions of the Permit to Fly, and pass the microlight General Flight Test. Again, for full details check LASORS and/or www.nppl.uk.com

Once you have jumped through whichever set of hoops is appropriate then you’ll want to fly. Until relatively recently microlights were not able to be hired, which meant of course that once you were solo you had no choice but to buy your own aircraft or join a syndicate to finish off your training! Some schools still operate in this way and will have several syndicate aircraft at any one time, with students buying and selling their shares to each other as they qualify. Many schools now will allow you to train on school aircraft all the way to your GFT including all solo and qualifying cross-country required. Some flight organisations are now hiring out microlights to qualified pilots in the same way as Group A clubs hire their aircraft out. There are not too many operating as yet, and there is one large limitation – you can only hire microlights for solo flight or dual instruction, you can’t hire and take a passenger. This is going to put some off, but if you don’t want to jump into ownership straight away then you can keep yourself current and have fun in a good performing microlight from around £40 an hour wet, or in a new-breed hotship from about £60 an hour wet.

Owning:

Owning a microlight aircraft is straightforward and is no different in principle to outright or shared ownership of any other aircraft type. Microlights must be registered and ownership details must be declared to the CAA (see the G-INFO database at (www.caa.co.uk/application.aspx?catid=60&pagetype=65&appid=1 ). It is compulsory for the aircraft to be covered by third party / passenger liability insurance, and there are a number of specialist insurers with experience of covering microlights. The BMAA is responsible for informing the CAA when it annually revalidates Permits to Fly. The owner is solely responsible for the airworthiness of the aircraft and the pilot (if different) for ensuring all the relevant documentation is valid. Used microlights are tending to hold their values well at the moment so whilst you shouldn’t view buying a second-hand machine as an investment it shouldn’t depreciate to nothing within a couple of years!

Costs:

Many people see the cost of running a microlight to be its biggest draw – it’s one of the cheapest ways to get your own aircraft and stay airborne. Obviously costs will vary depending on type, engine, hours flown, etc, but I’ll list costs that I have to pay to give you an idea based on a run-rate of 100 hours per year.

(1) Insurance - £800 per annum
Many people who run older style microlights fly with 3^rd party and ground risk only, some even doing away with the latter. Figure above is ballpark for a traditional three-axis microlight, insured for £1M of 3^rd party cover, and ground and flight hull risks (aircraft value £9k). Removing the hull risk element will save over £400.

(2) Annual Permit and Inspection Fees - £200
This covers the cost of the inspection and check flight and the fee to the BMAA for doing all the paperwork and notifying the CAA of the permit grant.

(3) Maintenance – £350
If you feel competent then there’s no reason why you can’t do all the engine and airframe maintenance yourself with support from your local Inspector/engineer. Engine and airframe manufacturers lay down schedules of maintenance to be followed, and the engine and airframe logbooks must show that these have been carried out before an Inspector will sign off the Permit. This particularly applies for any mandatory modifications that have been promulgated by manufacturers. If, like me, you’re not happy doing anything other than the basic 50-hour service and checks then there are plenty of specialists you can employ to get things done. Prices vary, of course, but assuming you don’t do any work yourself at all then parts, consumables and labour at about £300 - £400 per annum is probably about right averaged out over a few years.

(4) Hangarage and club fees/airfield fees - £400
These are very variable. Parking on the grass will naturally cost less than in a hangar. Flexwings are generally very easy to fully or partially de-rig which can reduce hangar costs to a bare minimum. Some three-axis types have cunning wing-fold mechanisms that give similar benefits. Allow somewhere between £300 and £1200 per annum unless you are lucky enough to have your own strip and/or hangar. Club fees seem to vary with the facilities involved, but somewhere between £5 and £15 per month seems the norm. Incidentally many airfields charge a reduced landing fee for visiting microlights compared to Group A aircraft, but some do not (e.g. at time of writing Kemble charge £6 for a microlight, £12 for a Group A. Wellesbourne charge £10 for both). I have used my own annual costs for the purposes of this exercise.

Total -
Annual fixed costs are therefore approximately £1,800. If we factor in 100 hours of unleaded fuel at 10 litres per hour this adds another £880 assuming 88p per litre. Add in another £300 for landing fees and we get a grand total of just under £3000. At 100 hours per year this gives a true total flying rate of under £30 wet per hour all in for the privilege of owning and flying your own aircraft whenever and wherever you want to. Joining a syndicate can drop this rate even further as you pay only a share of the fixed costs like insurance and hangarage, but you lose the flexibility of being able to fly whenever you like. Obviously you will need to do your own calculations based on your own fuel consumption and maintenance schedules, etc, but I hope this has given you a reasonable idea of what might be involved.

As an aside, I’m often asked about unscheduled costs, so here are some examples for my aircraft:
Complete re-cover (parts and labour) - £4,000
New engine (fitting extra) - £4,500
Major engine overhaul (parts and labour) - £1000 (my engine has a TBO [time between overhauls - ed. ] of 800 hours)

So after all that… why?

Well, why not? If you can fit in one, have a go. An hour’s trial lesson with an instructor will cost you between about £70 and £100 depending on the school and aircraft type. If you go for a flexwing, then it’ll be a completely different experience, and even if you can’t ever see yourself doing it again I bet you’ll come back with a smile on your face. In terms of three-axis then the zippy modern types are lovely to handle, but why not get yourself into a Thruster or a Shadow (or even an AX3/AX2000?!) and try something that’s just a bit different that you actually have to fly all the way to touchdown? The BMAA   website ( www.bmaa.org/) ) has plenty of information and can provide you with details of approved schools/instructors in your area.

Whatever you fly, fly safely and enjoy it!

_{Thanks to CW for proof-reading, and PS for LASORS research.}

Simon Newton, 11 Mar '06

Many thanks to Simon, who was (until a recent family new arrival) a very active AX2000 pilot flying out of Enstone, for permitting the Club to reproduce his article here.

In 2007 it actually became even easier to own and fly your own microlight.  If it falls within the following category -- single seater, and empty weight of 115kg or less, and empty wing loading of 10kg per square metre or less then it is exempt from the need to have a Permit to Fly. (Effectively it is treated for regulatory purposes like a hang-glider or paraglider.) Microlights falling within this 'Single Seat De-Regulated' ('SSDR' ) category are also more likely to be capable of storage at home, in your garage, and transport to the airfield/strip in a standard estate car without the need for a trailer. It's an exciting development and the manufacturers are responding by producing a glut of new designs within this new class of microlight.

The BMAA has also produced these introductory leaflets to microlighting -- www.bmaa.org/upload/misc/bmaa_folder.pdf www.bmaa.org/upload/misc/bmaa_final_inserts.pdf Tom Brearley, 7 Jan '09 DSMC

If you've read this far you're probably pretty interested in microlighting. This further articile by Guy Gratton, former Chief Technical Officer at the BMAA, provides an excellent introduction to the differences between operating light aircraft and microlights, and (I think) says something about the philosophy of the sport. The article was written in 1999 and it should be noted that -- technology has moved on a lot in the last 10 years. Guy's comments are therefore more relevant to 'old school' microlights rather than fast new machines. Since the article was written, differences training for Group A/SEP pilots to fly microlights has become mandatory. Guy no longer works for the BMAA. He divides his time between working at Brunel and (mostly) Cranfield Universities, although he is still flying microlights regularly and is a BMAA and LAA member. Many thanks to Guy for his permission to reproduce his article here. Tom Brearley, 8 May '09 DSMC

Flying Microlight Aircraft - safety for non-microlight pilots
by Eur.Ing. Guy Gratton CEng BEng(Hons) MRAeS MIMechE
(based upon a talk given to the 1999 PFA airmanship awareness day at Kemble)

Microlight aircraft are some of the safest, cheapest and most fun aircraft flying in the UK. The fatal accident rate, at around 1 per 30,000 flying hours is similar to that of General Aviation overall, and rather better than some parts of it in recent years. However, at the BMAA we see several perfectly serviceable aircraft per year written off by very experienced GA pilots, typically with several thousand hours. Why? - well because they are different, not more difficult or more dangerous, just different. The phrase “it’s only a microlight” has as much validity as “it’s only a jet fighter” all aircraft will treat you back as they are treated. Microlights fall into three basic flavours, 3 axis, weight shift, and powered parachute. The three are completely different in design and control, but can be flown on the one license - a situation which surprisingly has not created many problems over the years; mainly because any pilot worthy of the title will always realise that they don’t understand the different controls and operation involved and will happily pay a microlight QFI the required beer vouchers to do the necessary conversion. A conversion between control systems usually takes 10-12 flying hours and most microlight schools are quite happy to take you under their wing.

3 axis versus weight shift (Thruster TST and Pegasus Quantum)

The real problems seem to come when a pilot experienced on “light” or not so light aircraft elects to fly a microlight, using their existing license and experience. The problem is that although their flying experience should equip them well to fly a microlight, there are perhaps more things they don’t understand than they realise. In this article I hope to cover some of those things, and perhaps show that microlights aren’t dangerous but do need a bit of respect.

The Inertia / Drag Problem

The two biggest differences between a microlight and a larger aircraft are that they possess much less inertia combined, usually, with a much draggier airframe. This means that particularly when decelerating, the microlight can change speed much more rapidly than light aircraft or gliders. Imagine the scene of an inexperienced pilot who suffers an engine failure in the circuit - the first reaction (before brain kicks in) may well be to maintain height…

Light and draggy - the AX3, a typical microlight trainer

In a typical light aircraft trainer, you are perhaps flying downwind at 80 knots, and the stall speed is about 45 knots. If the pilot starts pulling the stick back, the speed will probably bleed off at around 1½ knots per second. That gives over 20 seconds of mishandling for the pilot to wake up, put the nose down, and avoid stalling the aeroplane.

In a typical microlight, you are perhaps flying downwind at 45 knots, and the stall speed is around 25 knots. If the pilot starts pulling the stick back here, the speed will bleed off at more than 3 knots per second - giving perhaps 6 seconds for the pilot to react correctly before the stall.

This characteristic also comes into play in the approach and landing. In a typical light aircraft, the approach speed is likely to be around 1.3 Vstall, with roundout starting at perhaps 25 feet. Try that in a microlight and you’ll stall 15 feet above the ground and be looking for a new aeroplane; here an approach speed of around 1.7 Vstall (say 50 knots in an aircraft that stalls at 30), and the roundout starts at about 10 feet. This is obviously a very unusual picture for those used to have more energy and less drag, but anybody can learn the trick after an hour or two with a microlight QFI. Of course, there is no cloud without a silver lining and this does allow you to use some very small strips; the BMAA training school criteria requires at least a 250m runway, and most experienced microlighters in most types can cope with rather less.

[Image]
Late roundout and flare (Thruster T600T)

Know your Engine

Microlights are well known for the distinctive drone of the 2-stroke Rotax engine which is as much a standard item on a microlight as a Lycoming is on a light aircraft. It would be fair to say that these engines don’t have the greatest reputation in the world, but they are designed for this class of aircraft. That is to say they are designed for aircraft which are operated usually by one person, who also does the servicing, and needs to know their engine very well. So, those of us who learned to fly in microlights from scratch know and love our Rotax engines. We check them regularly, we know the vagaries of how to start them on cold mornings, and how to spot a gearbox whose torsional shock absorber is on its way out. If you are going to operate a microlight, and don’t wish to add to the bar gossip about “unreliable Rotaxes” it is important to know your engine, even more than it is for a light aircraft. The good news is that most BMAA (and PFA microlight) inspectors do know the Rotax engine well, and are glad to pass on their knowledge; failing that, the Rotax importer, Skydrive and many other companies and clubs regularly run courses for private pilots on how to look after their engines. You never stop learning in aviation, but here it just doesn’t stop at the cockpit.

Personal Equipment

In a light aircraft you are encouraged to dress for the outside environment, to wear a lifejacket over water and if performing any more entertaining manoeuvres to wear a hard shelled helmet. In a light aircraft this is in case anything goes wrong - in a microlight much of it is for the actual flight; gloves, thermals, a helmet and other protective clothing are often essential for the conduct of the flight - enough said.

Typical microlight flying clothing

Range and Endurance

Microlights are by their nature slow and light. So, changing the fuel state or adding a passenger make a huge difference to the speed achievable, and the fuel consumption. Certainly a typical 2-seater such as a Thruster might experience almost a 50% increase in fuel burn through adding an adult passenger. This means that range and endurance in a microlight is quite difficult to calculate, and certainly very few manuals will give you much in the way of moral guidance on the subject. What this comes down to is that the pilot is required to get to know his or her aircraft very well - to learn the typical and maximum fuel consumptions at the weight and speed they normally fly, and use that in their flight planning.

On the other hand most microlights do come with an inbuilt advantage over many light aircraft… the sight gauge. Generally the fuel gauge will be a sight tube up the side of the tank, so at least you will know exactly how much fuel is in the tank - rather than the rough guesswork which is usually involved in the crude float and capacitance gauges fitted to a great many light aircraft.

Micro-Meteorology

The combination of low speed (a cruise between 35 and 65 knots) and low wing loading (rarely exceeding 25 kg/m²) mean that microlight aircraft are much more affected by the weather than probably other class of aircraft except balloons. In navigation, the 10 knot headwind which is no more than a minor consideration in a light aircraft cruising at 80 knots can change the time of flight by 25%, and 20 knots can limit you to local flights only. Pilots have run out of fuel in microlights through failing to take proper account of wind conditions, and certainly it can cause great difficulties if you were planning a precise arrival time or were trying to extend your range to the further possible limits. However, being small and slow, we can of-course take advantage of a great bane of many heavier aviators lives - vertical wind shear. Microlight cross country flying often becomes an exercise in reading the terrain and knowing where the wind speed is likely to be most beneficial; anybody who has learned white water canoeing will be very familiar with the concept.

Turbulence is also a great issue, the low wing loading of a microlight makes it far more affected by turbulence than most other aircraft, and although it is possible to fly most microlights in quite horrendous conditions (it’s a bit like going into the ring with Frank Bruno, roll with the blows and wait for it all to stop), microlight pilots help themselves a lot by looking at the terrain and avoiding woodland (which causes rotor), freshly ploughed fields and car parks (which create thermals), or the downwind side of towns and hills. I’m not saying this isn’t done by other aviators, but not wishing to see our passengers’ lunch again, microlight pilots need to be more aware of the surface than perhaps is necessary in something a bit heavier. (If you are demonstrated a microlight aircraft by an experienced pilot who then offers you the controls - if you’ve just started to fly over some woods, you may have upset him.) Final approaches over woods are a particularly enjoyable experience and generally require the pilot to apply yet more speed on the approach.

Visibility is another issue where microlights are different. A few months ago I sat in the back of a Piper Cub with a friend for a flight of a hundred miles or so. The visibility was just VMC, 5000m which at around 85 knots gave a visibility ahead of under 2 minutes. This was rather unsatisfactory for navigation, and wholly unsatisfactory for lookout, so my friend very sensibly turned around, landed, and we continued by car. Had we been flying a microlight however, we could have trimmed the speed back to perhaps 40 knots, giving over 4 minutes visibility ahead and much more time to get the navigation right. Admittedly it would be no faster than travelling by car- but it beats the M25 any day. So, as with small strips, this is an area where it is possible to operate a microlight safely in conditions that other aircraft should not sensibly do so.

Maintenance

BMAA microlights (which is most of them) are operated on a different basis to aircraft with a CofA or even a PFA permit. The responsibility for care and maintenance of the aircraft rests almost entirely with the owner. Annually, a permit renewal inspection and check flight are of-course required, but they are done on the basis of an independent audit of the owners own good maintenance of the aircraft - they are not a strip down inspection like a C of A renewal. So, the pilot used to paying a licensed technician to oversee their aircraft, or to hiring a club aircraft and letting somebody else look after it, needs to do some rapid learning if they are planning to go the microlight route. Standard BMAA maintenance schedules exist for aircraft which do not already have an approved maintenance schedule contained in their operators manuals but, regardless of the schedule, the price of cheap flying is the time and effort getting to know your aircraft and looking after it.

[Image]
The owner must know his or her way around the aircraft and engine.

Finally, please don’t let me put you off. The point of this article is to say that if you wish to fly microlights (and I hope if you do you enjoy it), please display the sense of a competent aviator and spend some time with an experienced microlight pilot, preferably a QFI, so that you can enjoy the experience safely. Microlights aren’t dangerous, just different. Details of microlight clubs and microlight flying can be obtained from the BMAA, phone 01869 338888; www.bmaa.org

 Guy Gratton, 1999

Devon & Somerset Microlight Club
Dunkeswell Airfield, Dunkeswell, Nr. Honiton, Devon EX14 4LJ
Club Tel: 01823 256046
Flying School Tel: 01404 891880