Bird Control Unit
When a bird hits an aircraft this is known as a bird strike. Bird strikes are the single greatest cause of accidents sustained by military aircraft and tragically the loss of human life or serious injury to aircrew. As most birds fly below 1000 feet and the majority of them below 500 feet above ground level, so it is the aircraft flying at low level, taking off and landing, that is the most vulnerable. Losses of military aircraft have been numerous and costly and in some cases lives have been lost. With this in mind, in 1965 the Royal Navy implemented a bird control programme at the then RNAS Lossiemouth in Morayshire Scotland.
Pre 1965, Royal Naval Air Station (RNAS) Lossiemouth averaged four bird strikes per month. For example, in Novemebr 1964, Lt Ian Parkinson on his final student flight with Lt M Spinks in a Hunter T8, hit 18 birds just after take-off. Luckily none went down the intakes and the pilots did not have to eject. Between 1965 and 1972 when the Bird Control Unit was in operation, RNAS Lossiemouth did not have a single bird strike during daylight hours. The methods used were: broadcasting the sound of birds in distress, pyrotechnics, shotguns and the most effective - falcons.
In 1972 when the RAF took over RNAS Lossiemouth the Bird Control Unit moved to its present location at RNAS Yeovilton and began operating using similar methods and in 1975 the operation was extended to include RNAS Culdrose in Cornwall. This resulted in significant bird strike reductions at both air stations.
Falcons as a method of Bird Control
The Royal Navy has used falcons as a method of combating bird strikes since 1965. Falcons have been used as the primary method of bird deterrent for the following reasons:
(i) The falcon, being a natural predator of other birds, will clear offending flocks of birds from the airfield and its approaches more quickly, and the birds will not return for some time after the falcon has left.
(ii) The approach areas to the main instrument runways to RNAS Yeovilton and Culdrose are inaccessible to vehicles, however the falcons can be flown in these areas. The falcon can clear many areas where a vehicle has no access.
(iii) There is the additional problem of livestock in the fields adjoining the airfields and the approaches. In these circumstances it is more beneficial to fly the falcon thus reducing the risk of frightening the animals with bangs etc. and upsetting the local farmer.
Finally it should be noted that falcons are only one method of bird control and cannot combat the hazard of bird strikes on their own.
Domestic Breeding of Falcons at Yeovilton
To overcome the problem of finding a source of falcons, a breeding programme was initiated in 1977 with a pair of Lanner falcons. Today the main falcons used are Peregrines. The breeding programme has now become so successful that all the falcons used at RNAS Yeovilton and Culdrose are bred domestically.
The breeding itself is on a double-clutch basis. The first clutch of eggs (normally four) are taken from the parents and placed in an incubator, and the second clutch is removed and replaced by the incubated chicks of the first clutch. By returning the chicks to the parents it is possible to avoid the possibilities of “imprinting” the chicks with human parents with which it might identify.
The chick remains with the parents until it is feeding itself and is flying strongly. At this stage the young falcon is either moved to a nursery aviary or removed to commence training.
Training Falcons for Bird Control
A young falcon at RNAS Yeovilton normally commences its training as early as possible. As falcons are more affected by visual stimuli than they are by noise - an aircraft take off near by will go seemingly unnoticed. For this reason the first few days are devoted to acceptance of the hood, which provides a calm and relaxing environment when the bird is on the fist, or travelling in the vehicle.
The falcon is then introduced to feeding on the fist; then jumping to the fist to feed. This is followed by short flights to the fist - again to feed. The next stage in training is the introduction to the lure, which is an imitation bird or animal used to entice the falcon. They feed on the lure for a few days before the next radical phase - the creance (a light line that can be attached to the falcon). Flight distances from fist, block or perch to a food-laden lure is gradually increased, so that a positive food association image of the lure can be imprinted on the bird.
The critical stage in the training is reached when the falcon instantly recognises the lure as a source of food and flies directly to it. It is the speed with which the falcon reacts to the lure that signals the progress of the training programme. The creance can then be removed for the bird to be flown free. A falcon’s flight performance is critically related to its flying weight. Falcons may grow fast, but they take time to become fit and strong and expert at flying.
Bird Control in the Royal Navy has now been operating for over 48 years its success significant and measurable, only one bird strike every 90,000 airfield aircraft movements. However it is not enough to have all the latest Bird Control methods available to clear an airfield if the people involved are not experienced in their use. Much success has been achieved in Royal Naval Bird Control throughout the past forty eight years and the personnel involved have accomplished this through hard work, expertise, determination and dedication.