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Everything Under Control - Combat

I'll fight you...

Flying two (or more) C/L models against each other in a form of aerial combat is far older than many people realise. The writer first flew combat in 1950 and by 1957/8 it was easily the most popular form of C/L flying in this country. Since then the number of competitors has steadily declined and the introduction of numerous classes has further reduced the numbers in any specific event. Nonetheless, it is still extremely popular.

No, they don't shoot each other down! Two models are flown in the same circle and each tows a paper streamer. The object is to cut your opponents streamer - usually as often as possible. Various means of scoring a 'bout' are used. A typical system awards points for each cut and deducts points for any time that a model spends on the ground. This is often the deciding factor since collisions - with each other and/or the ground are common. A well-drilled pit crew who can get a model back into the air quickly is an essential.

In some cases, it is possible to change the model during a bout - subject to various conditions. As is now common with most events, there are various classes ranging from 'Vintage' up to the FAI 'F2D' class. However, 'vintage' is a misnomer since the cut-off date is 1970.

The first published design in the UK was the 'Kombat Kapers' in 1954, designed by Robin Gibbard - now a noted wildlife artist. This was followed by many similar designs culminating in Mac Grimmett's 'Black Ghost'. This was built in vast numbers (for the time). The writer was a member of the West Bromwich club at the time and remembers 20 plus examples being loaded onto the club coach. And they were all powered by Copeman tuned Oliver Tigers! By some strange quirk of the current 'vintage' combat rules, neither of these designs is now eligible! One is tempted to think that this is because they are so superior to modern designs. Maybe we need a REAL vintage class.

As the event developed, the basic model design changed from the 'conventional' aeroplane to the flying wing. At that time, the performance of many of these was much inferior, but this was compensated by ease of construction and survivability.

A great step forward was the use of a 'stabilator' behind the actual wing. This probably originated in the USA with Riley Wooton's 'Voodoo'. The best known example in this country is the 'Early Bird', by Richard Wilkins - a free Model Aircraft plan. The writer built one in 1965, when the plan appeared, and still has it - a testament to it's strength.

In more recent times, the typical model has tended more to a small separate tail mounted very close to the wing. Such models can be bought ready-built of Russian origin and are built mainly of pine with transparent mylar covering.

Tank design has 'developed' back to very early origins, with 'bladder' tanks akin to the early balloon type. Here again the basic idea came from the US where they used 'pacifiers' - better known in the UK as babies dummies! More advanced types use a length of large diameter surgical rubber tubing sealed at each end. At one time a very popular tank was one made from a metal mustard tin - alas no longer available.

Simple to complex

Any control-line model can be used to fly combat, but it helps if the two models involved are near identical. The simplest possible model consists of nothing more than a plank of wood (or plastic foam) with a motor on the front, an elevator on the back and the tank and controls hung on top. Such a model would not handle very well but would probably take a lot of punishment.

At one time in the US, models became quite complex with intricate structures based around an I-beam spar and sliced ribs. According to one source, this is the origin of the 'Detroiter' I-beam stunters. These models were light and rigid, giving excellent performance at the expense of survivability.

The optimum design lies somewhere between these two extremes with the main qualities being strength and ease of repair. With these two requirements taken care of the effort needed to actually build the model becomes secondary.

Much the same thing applies to the actual streamer being towed by the model. For sport flying a length of crepe paper with a length of thread tied to one end will suffice. For competition purposes there is a rigid specification (Fig.1).

Streamer and string
Copied from BMFA Rule Book

The vast majority of competition flying takes place with motors of 2.5cc capacity flying on lines giving a radius of 52 feet 3 inches (15.92 metres) from the front face of the handle to the centre line of the model. This used to be 52 feet 6 inches, but metrication has changed that to something which isn't a round figure in either system of measurement. There are larger and smaller classes, particularly in the USA. Here again, if you are flying for fun any two similar models will do.

One area that has changed dramatically in recent years is in the stability of the model. At one time it was considered essential that the model could fly more or less on it's own while the pilot got his bearings and could plot a course to intercept the other model. Modern machines tend to be highly unstable to the point where it is quite difficult to fly them in a straight line. The writer was recently offered a flight with such a model and, after becoming blinded by the sun, actually spent some time trying to 'ditch' the model without being able to see it. The model refused to fly straight in any direction long enough to find the ground!


This has developed considerably since the early days, when anyone who could fly inverted was considered to have an unfair advantage. Indeed, there was at one time a rule prohibiting inverted flight beyond a maximum of half a lap. At that time the normal method was to overtake your opponent from above and dive through his streamer. Left-handed flyers like Mac Grimmett had a distinct advantage over the average flyer, although they were vulnerable to other 'lefties'.

This led the writer to develop the technique of constantly changing hands using a handle with a bar across the front to facilitate this. When lines became tangled, this helped to extricate your model. Sadly, this technique is no longer possible because there is now a requirement for the use of safety thongs to make it impossible to let go of the handle (Fig.2). This is actually a sensible requirement since a model can fly a long way with handle and lines attached. I have seen one wrap itself around a church spire!

Handle and safety strap
Copied from BMFA Rule Book

Watching a bout of combat in it's current form will leave the average spectator feeling distinctly dizzy. There is a bewildering succession of inside and outside turns and 'cuts' tend to very infrequent between two evenly matched flyers. This is far and away above the standard of the early days and personal fitness must play a considerable part in the proceedings.

When the BMFA was seeking recognition for the hobby as a sport, combat was cited as being very similar to fencing and heart monitors revealed that it could be very strenuous. At this level, of course, the beginner has a lot to learn and this can only be done by frequent participation in combat contests.

The classes

The BMFA rule book (details at the end of this article) contains detailed rules for all of the current UK combat classes. With the popularity of Phantom Racing and Phantom Speed (both aimed the the KeilKraft 'Phantom' design), it continues to amaze me that no-one yet seems to have thought of Phantom Combat.

We have already mentioned the 'Vintage' class, which has a list of designs currently containing no less than 101 different models, although some are no longer eligible as mentioned earlier. Another list contains 20 permitted engines. There is another version of this class which is limited to Oliver Tiger motors and called 'Oliver Tiger Combat', which adds 3 more designs, including the 'Black Ghost' and George Aldrich's 'Peacemaker'.

The main FAI class, 'F2D' allows any 2.5cc motor to be used with a silencer of strictly controlled dimensions and any fuel system. A second class ('F2E Diesel Combat') limits the motor to a diesel running on suction feed only.

'1/2A Combat' allows any 1.5cc motor to used with suction feed only and these models are flown on 13.5 metre lines. Note that, in the USA, 1/2A refers to motors of 0.049 cu. in. (0.8cc) capacity and they have a flourishing class for those motors and they also have a class for 0.35 cu. in. (6cc) glow motors.

Yes, there are other classes, but we have confused you enough!

Sources of information

The BMFA rule book (Contest Rules Section 4 - Control Line Book 2) covering Team racing, Combat and Carrier (current cost 3.00), can be obtained from:

British Model Flying Association,
Chacksfield House,
31 St Andrews Road,
LE2 8RE.
Tel: 0116 244 0028, FAX: 0116 244 0645.

Frank Smart runs a Vintage Combat plans bank and mail order scheme. For more information and price lists, send 1.50 in stamps plus an A5 SAE to:

Frank Smart,
High Street,
Upton St Leonnards,
Gloucester. GL4 8DJ.

Never fly control-line models near overhead electric power cables

Other articles in this series.
Handles Lines Controls Hinges/Tanks
Stunt Teamrace Speed Carrier

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