Technical Aspects of Kiting for Falconry

Over 30 years ago falconers began experimenting by using helium-filled weather balloons carrying bait to entice falcons aloft. Around 18 years ago in North America David Scarbrough went a step further by introducing kites so that falconers who lived in the windier parts of the world could do a similar thing when training their falcons to take a pitch on the way to becoming high-flying gamehawks.

I know of a number of kiting 'methods' used by successful British and North American falconers. They will of course differ in the detail from falconer to falconer but are broadly as follows:

1. A short stint on the kite up to modest heights (2 weeks) followed by traditional entering to game.

EQUIPMENT

When using kites in order to train hawks a certain amount of thought needs to be given over to the fact that different or modified equipment will be required over and above that equipment used by regular kiting enthusiasts.

The Kites

There are numerous types of kites available for all sorts of kiting activities but what is required for falconry training is a single-line kite that will hold steady and maintain as steep an angle as possible in the sky whilst also carrying a certain amount of weight in the form of baits, rigging and, of course, the line. Whilst other kites have been experimented with from time to time with varying degrees of success there can be little doubt that delta kites and their derivatives fit the bill almost perfectly when used for training hawks.

Delta kites are designed to operate within a certain range of wind only and there isn't a single model of kite that will cover all of the wind conditions that a falconer will be likely to train a hawk in. For this reason a falconer hoping to utilise the kite to train a falcon to achieve pitch in a variety of wind speeds will require at least two different kite models and in all likelihood, three or four. This is because most deltas are designed to cover only two wind-types on the Beaufort scale and flying in lighter winds than recommended will result in the kite stalling whilst flying in stronger winds may result in damage to kite or line. For example I use the following Dan Leigh kites to cover wind speeds from 1mph up to 25mph:

You will notice that there is a certain amount of overlap between the kite models I use and there is good reason for this. Wind is akin to a living thing that has a great deal of variation in terms of speed and direction and seems to have a 'mind' of its own at times. Every wind will have both a 'gust' speed (highest speed reached at a particular altitude and within a certain area & time frame) and a 'lull' speed (lowest speed) together with a great deal of variation in between. What the falconer will need to do is match the most appropriate kite to the situation (whilst remembering that no two winds are exactly the same) if he is to enjoy a successful training-session and avoid potential damage/loss to both kite, line and other equipment attached to the kite or line. If he is successful he will have a kite flying in a wind that will neither be too light nor too strong for that particular model but under certain conditions even using four kites as I do won't enable the falconer to make a risk-free choice of kite. For example, in a wind fluctuating between 10mph & 25mph or 4mph & 14mph you will be hard pushed to find a kite able to cope and will almost certainly be taking risks if you choose to put a kite aloft.

When used for falconry your typical delta will need to have modifications made that allow for attachments at the front (for attaching line), back (for attaching 40ft tail & transmitter) and an extra 'D' ring about 6" behind the normal towing-point on the 'keel' of the kite (for attaching certain rigs that hang bait directly from the kite itself).

There will be occasions when there is simply not enough wind for even the best of light wind kites and these occasions can be extremely frustrating for the falconer to say the least. The balloon might seem to be the answer and, indeed, in some parts of the world local conditions dictate that the balloon gets more use than the kites. However, generally speaking and particularly in the UK, when there is no wind at or near ground-level there is frequently a decent breeze high aloft. In terms of flying a balloon this will mean that it gets blown further away from the anchor-point until the flying-angle becomes so shallow that most of the desired altitude is lost. The answer is a hybrid between kite & balloon called a Kytoon which was invented over 60 years ago by Domina Jalbert - the modern version of which is called a Helikite and will fly in no wind but also in moderate breezes so that at least a 45 degree angle is always maintained whenever the wind blows. Unfortunately this is a very expensive option since not only is the Helikite's purchase price high but so is the cost of helium to refill it!

The Line

There are a number of falconers that believe that the use of a single kite in conjunction with several different lines of various breaking-strains is the answer to kiting in different wind conditions and avoiding damage to the equipment. Whilst using heavy duty line in strong winds will probably ensure that the line doesn't snap it is the kite that will be taking the brunt of excessive wind speeds and damage to a very expensive item will be the likely result. Also the use of overly heavy line will affect the aerodynamics of the kite in terms of the drag on the line caused by not only the weight of the line but the effect of the wind on the line itself. This will prevent the steep angles that are required when kite-training hawks and will significantly affect the outcome of the session - especially if the falconer is restricted to using the 'slide-down-the-line' method.

The answer to operating in different wind conditions is to use a single-line set-up and choose the correct model of kite for each situation. Braided line of some description is what is required - do not use monofilament as it can and will break without warning with potentially disastrous results whereas braided line will show signs of wear before eventually succumbing although flying the wrong kite for the conditions can of course still cause a break without warning. The lightest, thinnest, strongest materials are probably specialist kite-lines made from Ultra-High-Molecular-Weight Polyethylene (UHMWPE) such as Spectra, Dyneema or Coramid although there are some excellent & comparable deep-sea fishing braids available made from the very same gel-spun polyethylene fibre. These lines have high strength-to-weight ratios, are resistant to moisture & UV light and exhibit low stretch when compared to Dacron. However this low elasticity is a drawback in the case of stress absorption in terms of sudden jerks or snatches on the line. One of the other characteristics of this material is its inherent slipperiness which makes for problems when tying knots and difficult handling even when using gloves but means it is highly abrasion-resistant. The choice of material is down to personal preference although if you are using the 'slide-down-the-line' method then one of the safest choices is Dacron as these other, better performing braids have a rather low melting-point when exposed to friction. Certain of the alternative high performance lines used in the past on stunt-kites and the like are totally heat-resistant unlike UHMWPE but extremely abrasive under tension and due to the extremely small diameter in comparison to Dacron are more likely to cut into flesh which can result in serious injury to both falcon & falconer if things go wrong! Both UHMWPE and Aromatic Polyamide (Aramid) & its derivative, Para-Aramid (Kevlar & Twaron) lines should therefore be used with great care with the sliding-rig for different reasons.

When choosing the weight of the type of polyester known as Dacron (manufactured from Polyethylene Terephthalate or PET) you are looking for 50lb minimum breaking strain for the light wind kites (anything thinner will break too easily) and 100lb for use with stronger wind kites (anything thicker attracts too much drag) although for the recommended single-line set-up a 75-85lb rating is ideal. When choosing weights of line from other, higher performing, materials you would be well advised to go for 100-200lb rating since that would still be less than Dacron of around 50-100lb in both weight and diameter but will give you the extra margin in terms of breaking-strain which can be vital in terms of increased 'snatch' breaking-strain.

In terms of length of line required this will vary with what the individual falconer hopes to achieve by kite-training his hawk but certainly when kite-training for pitch I think that a minimum length of 1000ft and a maximum length of 3000ft is what is required. The shorter length will give between 600 & 900ft of vertical height depending upon conditions and equipment used and the longer length will give around 1200-2000ft since the 'law of diminishing returns' kicks in as drag increases its effect upon your line. I would suggest that kiting to less than 500ft would probably not be worth it in terms of attempting to positively influence the pitch of your hawk and kiting to more than 2000ft would mean that even the largest of falcons would be almost invisible to the naked eye at such heights.

Whilst I have recommended a single-line set-up this doesn't preclude the use of different lines with the appropriate kite for the wind conditions. For example the use of 50lb Dacron with a light wind model might mean the difference between flying or not or 100lb Dacron on a particularly breezy day might save you from losing a kite to a broken line. Personally I use a single-line set-up with four different kites to cover a wide-range of wind speeds so use 75/88lb Dacron with my rolling-rig and since my rig incorporates a block-pulley and rolls down the line very efficiently the larger diameter of the Dacron compared to the high-per lines helps avoid snagging & therefore safety/friction problems.

However I mostly use the 'O'-rig with my kites or a fixed/sliding rig with my Helikite so that allows me to use better performing lines. My choice is 0.38mm/56.2Kg Stealth High-performance Braid from the range of Spiderwire deep sea braids as I get high angles due to its low drag owing to high strength versus minimal diameter characteristics whilst still avoiding the safety/friction problems of some other high-per lines due to its inherent slipperiness & Teflon coating.

Reels

Kiting enthusiasts will generally use a hand-held reel of some description whilst actively flying a kite. However when kiting for falconry a static reel that can also be anchored to the ground in some way will be required. Hose reels have been used by some falconers but have generally been found wanting as the reel isn't strong enough to withstand the pressure of the line wrapped around it under tension. Other falconers have gone to the other extreme and had reels purpose-built or adapted winches to provide an excellent although expensive solution.

Electric fence reels probably fit nicely in between these two extremes as they are relatively inexpensive yet will last a season or more of frequent use if treated with care and the plastic/rubber parts anointed regularly with silicone lubricant where they come into contact with metal prior to powered rewinding. They also come with mounting posts so that the post can be sunk into the ground and the reel bolted onto the post but care should be taken to also add an anchor/safety line between the reel and post just in case the bolt ever comes loose from the post and the reel is pulled by the kite at high speed over the ground - an incredibly dangerous situation if there are houses, roads or railways nearby!

A further advantage of using electric fence reels is the fact that drill rewind adaptors can be purchased that will allow the fast, easy rewinding of kite-line when used with cordless drills. Some falconers use automatic winches that will wind in the line slowly whilst the kite is still in the air but great care must be taken as tremendous strain is put on equipment. A less risky solution is to bring the kite down, remove it from the line then wind the line in over the ground at the end of the session.

Tails

Tails are used to stabilise the kite when flying in turbulent conditions and vary in length from 6ft to 40ft or more although the longer tails are more effective. They work by adding weight/drag to the rear of the kite in a bid to prevent the kite from turning over and flying nose-first towards the ground or 'dive-bombing'. In really extreme conditions a weight can be tied to the very end of the tail. Alternatives to a tail exist in the form of a 'Drogue' - a small wind-sock on a line or a 'Tube-Tail' - a hybrid between a tail and drogue that allows air inside it and both can add stability to your kite in rough weather.

Downriggers

When using a kite for falconry there are various methods used to bring the hawk back to earth once it has flown up to the bait and the pieces of equipment used to accomplish this are known as 'downriggers'. There are parachute rigs, sliding rigs, remote-control rigs and rigs that bring the kite to earth at the same time as the falcon. All of these rigs have their devotees, but when making a decision the important things to consider are the weight of the rig (the lighter the better) and how much open space (devoid of roads, trees, power-lines, fences, houses etc.) the falconer has available for kiting.

Remote control rigs require less space than other rigs since the bait/lure is dropped from the kite once the hawk has climbed almost all the way to it and the kite is wound-down directly rather than running the line down over the ground. The drawbacks are the weight that the kite has to carry and the fact that the falconer has to possess a certain amount of technical knowledge in order to make one of these rigs.

Sliding rigs involve the running down of the kite/line once the hawk has grabbed the bait so therefore the falconer has control of where both hawk & kite come to earth. This can be advantageous where space is limited since the falconer can 'bend his run' around objects that would otherwise make kiting hazardous. They are light in weight and can be easily homemade but there is a very slight risk that the hawk can be injured (even with Dacron) if it grabs the main line as it is sliding down whilst running down 3000ft of line over uneven ground can be very taxing for the falconer. When using these rigs a roller or smooth stainless steel bar can be utilised to make running the kite down easier with minimal friction on the line and avoiding friction burns to skin and damage to leather gloves. A slight variation on the sliding-rig is the 'rolling-rig' which utilises a yachting-type block with a ball-bearing sheave (wheel) instead of the usual karabiner so that it will roll down the line without the falconers assistance from heights up to 500ft or so. Another plus-point with this rig is that it eliminates the karabiners' tendency to go up the line in strong winds once the bait is released by the hawk.

Parachute rigs require a lot of open space completely devoid of hazards since the hawk has a certain amount of freedom as it isn't connected to the kite/line in any way although the drag on the chute itself should prevent the hawk going too far. Like the sliding rigs they are lightweight and can be made at home by the falconer and like the remote control rigs the kite can be wound-down directly out of the air.

The 'O'-Rig was invented by a group of falconers from Oklahoma and facilitates the kite being brought to earth at the same time as the hawk once the bait is grabbed. It is lightweight and easily homemade and has the big advantage that the kite doesn't have to be brought down by the falconer and the line can be quickly reeled in at the end of the session. This makes it extremely useful when training multiple hawks in one session since the kite can simply be re-baited and the rig re-set before sending the kite back up for the next falcon. It requires as much space as the sliding rig with the disadvantage that the falconer cannot control where the hawk lands other than knowing that the hawk & kite will come down at the end of the line and roughly downwind of the reel. A further problem can be setting the tension accurately for the release mechanism when flying in very turbulent weather if you are to avoid either premature release or failure to release.

The final type of rig is little used but is the simplest of them all. This is the fixed-rig and requires the falconer to run the kite all of the way down to the ground since the hawk simply binds and hangs on to bait attached to the kite-line. This rig is best applied to the Helikite where the amount of helium is carefully controlled according to the size/weight of the hawk flown so that the hawk is able to pull the whole thing downwards.

Bait

The choice of the item that is attached to kite or line in order to entice the hawk upwards is largely a personal one. However the main consideration will be one of whether to use artificial or real baits and here is where the choice can be critical. A hawk will venture upwards for as little as a 'sock' or for an un-garnished lure of some kind provided that it has been accustomed to receiving a reward for retrieving such an unattractive item. The next step up will be a garnished lure but the most practical, safe and attractive of items would be a whole bird of some description. Of course a secondary consideration will be weight so the final choice may well be a compromise.

Wind Meters

Unlike the above items, wind meters aren't essential equipment but the falconer will be making things easier for himself if he is able to make an educated decision prior to putting a kite into the air. Just spending a few minutes determining gust & lull wind speeds with an anemometer will influence the choice of kite as well as the decision of whether to use a tail or not.

WEATHER

Whilst weather conditions such as fog, mist, falling snow or heavy rain can severely affect visibility and therefore make flying both kite & falcon inadvisable it is the wind that will dictate most of your actions when in the field. It is a 'living thing' and will change not only according to time & location but also with altitude and whilst wind speed can be affected by landforms and pressure systems in a phenomenon known as 'wind shear' wind direction is influenced not only by prevailing winds and landforms but also differences in temperature - for example between sea and land. This makes kite-flying extremely haphazard and fraught with difficulties since the very nature of wind can prove unpredictable.

Due to the above it is far from simple to give advice that can be followed by every falconer in every situation and still be successful. However, due to many years of experience in the field flying falcons to kites, I can outline some of the important considerations when attempting to fly a kite for a falcon successfully, safely and without incident.

The normal way of things is for there to be more wind the higher you go which means that the falconer will have to decide whether the kite he is flying will still be safe to fly at high altitudes. However there will be freak conditions where the wind up higher will be less than at ground-level or even non-existent. This is known as 'dead-air' and is the reason why on some days (usually in summertime) the kite will not climb above a certain height. The answer to this is either to put up your lightest wind kite in the hope that there is enough wind to take it through the dead-air zone or 'fly' your kite through the dead-air by letting out more line then winding line in quickly or even running against the wind whilst holding the reel........unless you own a Helikite!

Another problem you will encounter is when the wind speed varies so widely that a single kite will not be able to cover both gust and lull. The most serious situations will involve the lull wind speed being less than half of the gust wind speed. In these freak conditions the falconer will then be forced to fly a lighter wind kite than he would want to in order to prevent the kite stalling out when the wind drops to its lowest level.

A similar set of circumstances to the above can occur in the lightest of breezes when the lull wind speed drops to zero for more than a few seconds and the kite literally drops out of the sky. The only options available to the falconer are to actively 'fly' the kite into a higher position in the sky in the hope of picking up a higher lull wind speed or fly a Helikite instead.

By far the most dangerous of wind conditions the falconer can be faced with occurs with a combination of a widely fluctuating wind speed with a marked variation in wind direction (by an eight point of a compass or more e.g. N to NW). This combination means that as the kite begins to stall-out the wind direction changes and puts the kite into a vertical stoop towards the ground that can only be arrested by rapidly letting out more line. Whilst the conditions remain so will the likelihood of such unnerving 'dive-bombing' kite behaviour. A tail can help considerably when flying in such conditions and also in the turbulent conditions described below. In fact I always use a tail when flying my kites in a moderate breeze or above because of the greater risk of potential problems.

Another problem that will be faced by the falconer is when launching a kite or attempting to fly it at a low altitude. In the Atmospheric Boundary Layer nearest to the earth's surface the 'surface drag' causes turbulence which gradually reduces with height above the ground. It is this turbulence which can cause the kite to fly erratically until it is high enough to stabilise and it should be borne in mind that the rougher the landforms on the surface the higher the ABL will extend.

Linked to the above and for similar reasons the falconer should be aware of the presence of 'dirty air' or turbulence caused by the presence of objects upwind of the position of the kite. Particularly when attempting to launch the kite the falconer should ensure that he is downwind of any such object by a distance of at least five times the height of the object if he is to be able to launch without difficulty.

Judging Heights

When it comes to judging the height of the kite that the hawk is to fly to there are many methods. Range-finders & Altimeters are some of the more modern ways to determine the height of a kite above the ground but marking the line in 100ft increments then guessing the angle before using mathematical trigonometry (sines & cosines) to arrive at the answer have been used for a good many years and will give you a good idea prior to the flight. My own method is to estimate the angle of kite-line from vertical just prior to the flight then pace the length of line out along the ground post-flight before using the following simple calculations (based on cosine tables) to determine the height:

By walking a known length of line it is possible to determine how close your stride is to a yard and then adjust accordingly for all future calculations - I take off 10% from the paced out line result since my stride is slightly less than 1yd.

Telemetry

It must be borne in mind that a kite is an expensive item which the falconer can ill-afford to lose for two important reasons; financial & practical. It can put a big hole in a falconer's wallet if he has to replace a lost kite and time taken to obtain a replacement will be an important consideration if he has a new eyass to train. Put a transmitter on the spine or keel of the kite for this reason.

Legal Considerations

When planning to use a kite for falconry training it would be wise to check on your local laws in respect of the heights that tethered objects can legally be flown without permission of the authorities. In the UK Civil Aviation legislation applicable to kite flying is contained in Section 1 of the Air Navigation Order 2009 and the Rules of the Air Regulations 2007 Schedule 1 (Section 9). These are amended from time to time but for the purposes of these documents kites are classified as aircraft.

(2) Except with the permission of the CAA -

Article 164 (2) (b)
A kite must not be flown at a height of more than 30 metres above ground level within the aerodrome traffic zone of a notified aerodrome during the notified operating hours of that aerodrome.

Article 164 (2) (c)
A kite must not be flown at a height of more than 60 metres above ground level.

Rule 53 Captive Balloons and Kites by Day

53.-(1) A captive balloon flying by day at a height exceeding 60 metres above the surface shall have attached to its mooring cable tubular streamers which are - (a) not less than 40 centimetres in diameter and 2 metres in length; and (b) marked with alternate bands of red and white 50 centimetres wide at intervals of not more than 200 metres measured from the basket or, if there is no basket, from the lowest part of the balloon. 53.-(2) A kite flying by day at a height exceeding 60 metres above the surface shall have attached to its mooring cable either: (a) tubular streamers as specified in paragraph (1); or (b) at intervals of not more than 100 metres measured from the lowest part of the kite, streamers not less than 80 centimetres long and 30 centimetres wide at their widest point, marked with alternate bands of red and white 10 centimetres wide.

The above is an extract from the full regulations. For further details of the Act above look at the www.caa.co.uk. For permission to exceed the limits stated above you are required to complete an application form. Details from:

David Miller
Airspace Specialist 5 (AS5)
Airspace Utilisation & Off-Route Airspace (AU&ORA)
Directorate of Airspace Policy (DAP)
Civil Aviation Authority (CAA)

Tel: 020 7453 6585 (direct line) / 020 7453 6599 (AU Operations)
Fax: 020 7453 6593

Permission will be granted for 3 months at a time and 28 days notice will be required from application submission to start date. Each application will be dealt with according to the above legislation and also with reference to certain 'Flying Restrictions' as contained in the Air Navigation Order pertaining to the Scottish Highlands, Nuclear Installations, Prisons & other 'specified areas' notably in and around central London. Your individual permission will dictate where, when and to what height you can fly and in the case of flying near to Airports & Aerodromes may contain other provisos such as a call to the Air Traffic Control tower prior to flying. Sometimes this can place further restrictions on a kite-flyer dependant on METARs (weather reports) & TAFs (Terminal Area Forecast) given out by the local ATC containing information about visibility and cloud height. Your permission will act as a NOTAM (Notification to Airmen) so that other airspace users will have an obligation to avoid the airspace at certain times.

TECHNICAL ASPECTS of KITING for FALCONRY