This is probably the most commonly used film in the UK today. It is a polypropylene film with a pigmented adhesive layer. Advantages are that it is cheap, available in a wide range of colours including fluorescents, and can be used direct onto polystyrene foams. Disadvantages are that it will not shrink as much as polyester, and it can be hard to produce a wrinkle free result. It is also susceptible to bubbling when one layer is applied over another, due to gas formed when the adhesive/pigment is heated.

Rather than a smooth polyester film, Solartex is a woven polyester fabric, coated with a pigment. This makes it ideal for reproducing fabric covered aircraft, and is the covering of choice for models such as WW1 biplanes. It has very good shrinking properties, and is quite easy to apply. However, it suffers from bubbling when applying over another layer, and although it is fuel proof, it really needs a coat of clear fuel proofer to prevent dirt from becoming engrained in the fabric weave. Another disadvantage is weight.

This film is a polyester, with separate colour and adhesive layers. This means that it can be repositioned when applying to the airframe without leaving coloured marks. The adhesive works at quite low temperatures, but because it is polyester, high temperatures can be used to shrink it. Profilm is easiest iron-on film to use, and excellent results can be achieved, but it is more expensive than most other coverings. It is made in Germany and sold under the brand names of Profilm, Oracover and Ultracote.

This film is a polyester, with a single coloured adhesive layer. Although it is hard to find in the UK, it is the most popular film in the US, and many American ARTF models come covered in Monokote. In general, higher temperatures for application and shrinking are required compared with other films. The polyester layer is quite thick, making it durable, but at the expense of weight. I have used it a few times, and though it can gas and generate bubbles, this is less severe than the Solarfilm range.

Although plastic films are widely used, more traditional covering methods such as doped tissue, silk and nylon are still used, particularly for vintage models. These methods are generally more involved, and can be messy, they still have their adherents, and can give very durable, lightweight finishes when applied carefully.

One of the key consideration when choosing the covering method for a model is weight. A lightly built small aircraft will need a light covering if it is to fly successfully, and weight is a key consideration for electric aircraft. The table below lists the minimum and maximum weights in grammes per square metre for a wide range of covering materials, and I'm indebted to Michael Rolls from the RC Modelflying internet forum for the data. It is reproduced here with his permission. The variation in weights comes from different colours having different densities and the finishing method used. For example, silver Solartex is the heaviest of the range, and natural the lightest.