Building Your Own Kit Aircraft

They had already decided that no current factory model met their needs, and had determined that building from just a set of plans was not for them. This led to the conclusion that a kit aircraft was the only option for the type of flying they wanted to do. Jake and Barbara stressed that they were building in order to fly whereas some people build more for the building experience itself. The nearest commercially built aircraft to their requirements would be a Mooney or a Trinidad but these are over four times the cost of a kit and even then not all their specifications would be met.

Research soon indicated that the generally accepted best manufacturer of kits was the US firm of Stoddard-Hamilton Aircraft, the producers of the Glasair. However, before committing themselves, they spoke to other members of the Sport Aircraft Association of Australia, in particular other Glasair builders, about their projects and the support they were receiving from the selling company.

The Aircraft

The Jansen’s specification for the aircraft they wanted (or could justify in terms of cost) called for an aerobatic, side by side two seater, fixed undercarriage, constant speed, IFR capable aircraft, with a good range, high cruise speed, and economical to operate. Composite construction was a factor since the ideal shape and form of an aircraft is more readily achievable in this medium, and it is more environmentally friendly in terms of your neighbours since you don’t have to worry about the noise of knocking in rivets at all hours! The aerobatic requirement was not so much for competition but for the guarantee of structural integrity. The Glasair is stressed to ultimate loads of +9g/-6g-a comforting thought in heavy turbulence. With just the two of them, a two seater is all they require. If the occasion occurs that more seats are required then hiring the most appropriate aircraft is the best option. Saves a lot of hassles with friends who pack for the month for an overnight stay and wonder what all this weight and balance fuss is about! The fixed undercarriage relates perhaps more to the selected kit. The Glasair (on which more later) does have a retract version but at the cost of an additional $10,000, a 45kg (100lbs) weight penalty and about 500 hours extra work. All this for a 10kt (19km/h) gain in cruise speed, which is not much when you consider that the fixed gear version with a 160hp powerplant is capable of cruising at 170kts TAS at 8000ft (313km/h at 2440m) on 65% power. For the Jansens, it was an easy decision.

Finally, they needed an IFR aircraft with a good turn of speed and a range profile which would allow them to fly further afield than they could in the Robin.

Stoddard-Hamilton Aircraft Inc.

Before going into more detail on the Jansen experience, it would perhaps be helpful to provide some background de- tails on the firm producing the kit.

is Stoddard-Hamilton was founded in 1979 and their product now acknowledged as setting the industry bench mark. Years of research, development and customer feedback have perfected the Glasair kit for the novice builder. As Jake commented, after researching the market, the decision to opt for the Glasair was an easy one, it just fell out. The first Glasair kit was offered to the public in 1981; this was the Glasair in fixed tail dragger form (TD). Since that time over 1300 kits have been sold with, at the last count, in excess of 350 aircraft completed and flying for a total of 13,000 hours. The highest recorded flight time is now in excess of 2000 hours which has been achieved by the factory demonstrator.

Since the introduction of the first Glasair, an additional four models have been produced; a fixed tricycle (FT), a retractable tricycle (RG), a six cylinder retract plus a turbocharged retract. The latest versions of the four cylinder model are known as the Glasair II-S (TD, FT, RG) whilst the six cylinder models are designated Glasair IIIs.

The original Glasair was stretched in a model improvement introduced in 1986 hence the II-S designation. This unfortunately introduced stability problems requiring the tailplane to be lengthened by 200mm (8in) either side, or the wing moved back 38mm (1. 5in). Although the ldt has since been modified, those who bought earlier kits have to carry out one of the modifications during construction if they wish to fly IFR and carry full baggage with full fuel; this unfortunately is the case with the Jansen’s kit. Both the modifications are mandatory for aircraft with 150hp engines and wooden props.

The Kit and its Construction

As outlined in the brochure describing the product, the Glasair is assembled from preformed composite shells made in female moulds by Stoddard-Hamilton. This process assures accuracy and virtually eliminates the need for any complex jigging fixtures. Fabrication is very much like putting a giant model aircraft kit together.

The fuselage comes in two large half shells and three belly sections. The one piece full span wing has two upper panels and a massive I beam fibreglass spar which is bonded to the lower wing panel by the factory. The horizontal stabiliser and elevator are in halves and feature premolded ribs and shearwebs. The flaps, ailerons, and rudder, are also assembled by joining two half sections.

Stoddard-Hamilton maintains that an aircraft of the calibre of the Glasair, built of aluminium tube, fabric and wood would require a construction time more than double that of their product. The kit hardware includes all machined fittings and prewelded engine mounts, exhaust systems, and control sys- tems. All welding is factory finished and all metal components machined or formed, are deburred and finished with paint, cadmium plating, anodizing, chrome plating, or a number of other surface finishes depending upon the application. Finally, Stoddard-Hamilton offers a Glasair options catalogue featuring engines, constant speed propellers, governors, engine accessory kits, autopilots, fire suppression kits, antennas, tools and replacement parts for the various models. Not included in the kit are the engine and its associated controls and baffling, the battery and electrical system (no wiring harness), propeller, interior upholstery, instruments and avionics, lighting systems or paint. The reason Stoddard-Hamilton only supplies the kit to a certain equipment fit is that most kit builders wish to customise their aircraft as is readily apparent from photographs that the Jansens recently took of Glasairs at Oshkosh where no two aircraft were the same! It is possible to buy the kits in four progressive lots (at extra cost) and also to delay ordering the engine cowling kit if an engine has not yet been selected.

Finally, for those who may doubt their abilities to work in fibreglass, a rudder starter kit is offered for under $US500, which is deducted from the price of a full kit if the latter is purchased.

Stoddard-Hamilton is at pains to point out that the Glasair IIS-RG and the Glasair III are high performance aircraft and require the appropriate endorsements. Similar experience and endorsement is necessary for the IIS tail dragger, however the fixed tricycle IIS FT is placed in the GA trainer category in terms of general handling, but with a much higher cruise speed.

The Jansen Experience

Returning to the Jansen experience, having decided that Stoddard-Hamilton offered what they wanted, they set about ordering the kit direct from the factory, there being no agent in Australia. They imported the kit themselves and took delivery of the 7. 32mx1. 22mx0. 93m (24ftx4ftx3ft) wooden crate in Sydney. This was not without hassles as someone obviously in the know stole the wheels and brakes after a Customs check in Sydney, lets hope the thief crashes his gocart and breaks his neck! Whilst waiting for the kit to arrive, Jake built a 2. 4m extension on the front of one side of double garage to accommodate the one piece wing; he also insulated the whole garage to provide a reasonable working environment in our cool Canberra winters. The garage is even equipped with a fridge, TV and radio.

They also got their house in order making certain that all the odd jobs requiring attention were completed before setting to work on the aircraft. This is a recommended procedure for reducing any possible friction between dedicated aircraft builders and equally dedicated home makers! Getting down to basics, I put the question to Jake as to what skills were necessary or needed to be developed, to be able to put the giant airfix together? As might be expected, fibreglassing is the main skill required but this in itself is not a worry since precise instructions are provided on weighing, mixing and application techniques.

Samples have to be kept for SAAA inspection and destruction testing. The SAAA has taken over the responsibility for all inspections previously carried out by the CAA. These inspetions, which must be done prior to closing up any assembly are paid for by the builder.

One skill that has to be developed by those brought up on metrics is working in the old imperial measurement system of feet and inches, a step back to the previous century! Other skills are developed as you go and you soon learn what you can expect to achieve on a particular task in the time avail- able. For instance any fibreglassing job can take at least a couple of hours. However lesser tasks might be as little as half an hour.

Since the kit doesn’t include a wiring harness, if you’re electrically illiterate like me you will need to spend some time studying appropriate publications on the subject to be able to tackle the task of wiring with confidence.

The construction manual is excellent and provides unambiguous step by step instructions on how to complete each discreet item, which is then signed off at the end of that section. An introductory manual is supplied on the payment of the deposit which provides details on how to prepare for the arrival of the kit, such as building the necessary jigs.

Barbara acts as Jake’s apprentice. This was especially so in the early stages as she developed her own skills. She was particularly proud of the fact that she had installed the engine mount fuselage hardpoints on her own.

The Jansens have been working on their kit since its arrival in November 1989 but have not kept a detailed log of the hours spent on the job. Building time is somewhere between 1500 and 3000 hours, and takes something like two to three years. The fastest time to their knowledge was an aircraft put together in 17 months.

Both expressed understanding for spouses who were not involved in the building of a kit who turned anti aircraft as result of the cost to the family in terms of dollars and the hours their partners spent out in the shed. It certainly helps for both to be actively involved in such a demanding project as building an aircraft.

My initial reaction on first sighting their aircraft was that they appeared not to have made much progress. However as I was to shortly learn, many items had been completed, fitted up and then removed in order for other aspects of construction to be completed. For instance, the engine has been installed and subsequently removed.

The instrument panel has also been fitted up, including a most impressive set of dual analog/digital engine instruments. From the photographs that the Jansens took at last year’s Oshkosh, cockpit layout and in particular instrument panel style and equipment fit seem to be the areas where Glasair builders express their individuality.

Barbara has taken on the task of designing the cockpit interior and the paint scheme, the latter being essentially white because of the fibreglass construction. The aircraft will be painted in a two pack polyurethane finish in a spray bay when it is finished, but that will only follow quite a few hours of sanding back the fairly heavy grey primer in which the aircraft was delivered.

Photographs of all stages of construction are a requirement to prove that you have actually built the aircraft. Of course a photographic record for your own pleasure is something to bear in mind but it does require a little planning if it is to be a worthwhile record. Finally, when you have put it all together and know every inch of it in intimate detail, you will have to have it maintained by a LAME because those are the current rules. Seems a bit silly doesn’t it! Support provided by Stoddard Hamilton is first class (evidently not the case with all kit manufacturers) and a newsletter is sent out to all owners about once every three months.

The Jansens decided to take on the job of running an Australian newsletter for the forty or so builders in this country as a way of returning some of the help they have in turn received. This seems to be the nature of the do it yourself aircraft construction fraternity.

They have also taken on the task of organising the Glasair aspects of Mangalore ’94, which in the continuing theme concept of Mangalore is to be the ‘year’ of the Glasair.

Is it the way for you?

My conclusions from talking to the Jansens is that building your own aircraft from a kit is a practical proposition, not requiring extraordinary skills, but needing a fairly high degree of motivation. Although the Glasair and other kits can be built for a lower price, the Jansen’s IFR aircraft is grossing out CSU prop, instruments, avionics plus GPS and all the little at about $80,000 all up including the kit, a brand new engine, extras we tend to forget about. It is certainly a lot cheaper than a commercially built aircraft to the same specification. Nevertheless, such a project is not to be entered into lightly as it involves a fair amount of time; but it is definitely easier if there are two of you to share the burden. Not much more required, but of course this will depend on individual the space available in the average double garage is stances. Clearly you need to be organised and capable of planning the job and to be methodical in your work practices. In addition you must be prepared to seek advice and to take the time to read the many publications that have been written on the various aspects of owner building.

Finally, I hope, before the end of the year, to be able to report the results of a successful series of test flights (might be able to con a ride!), all completed of course in good time for the next Mangalore spectacular. We wish them luck.