The Tornado has a computer controlled fly by wire system that ensures optimum performance wherever possible. The system has multiple redundancy built in to accommodate any number of potential failures. The system is comprised of several units that interact to minimise the risk of the aircraft leaving controlled flight.
Flight Control System
The Tornado has a triplex electronic flight control system commonly known as fly by wire although the Tornado maintains a mechanical backup system. The benefits of an electronic flight control system are many, some of the benefits are as follows; reliability, faster response, less physical engineering complexity, more sensitive control inputs.
It should be noted that the failure of a combination of the systems will enable the mechanical direct input control system to become operational. This will usually transform the aircraft from one that can be thrown around with gay abandon to one that may be extremely sensitive to control input as the computers are not there to smooth and control the requests being fed to the operating surfaces. This type of system is usually only provided as a get you home option.
The system is comprised of several units which are detailed below.
AFDS - Autopilot and Flight Director System
SPILS - Spin Prevention Incidence Limiting system
The SPILS system is an integrated part of the Tornado flight control system. It's purpose in life is to ensure the Pilot cannot lose control of the aircraft during certain flight regimes. A term often heard when describing fly by wire systems is 'Carefree Handling'. This generally means that a Pilot can 'drive' the aircraft as they wish but this computer will stop any loss of control due to a request that the airframe cannot perform safely.
In the Tornado's case a computer sits between the aircraft controls and the physical controlling surfaces such as the tailerons, rudder and spoilers. The computer receives signals from the pilot through the controls and decides whether or not to pass these to the control surfaces as requested by the Pilot. The computer also receives a vast amount of information from sensors mounted within the airframe and compares these against what the Pilot is asking for. It then instructs the control surfaces to deliver the best possible performance available for the manoeuvre requested without causing a departure. A departure is generally any loss of controlled flight.
These systems are not foolproof, they will not for example stop the pilot flying the aircraft into the ground.
JTIDS - Joint Tactical Information Distribution System
JTIDS is in effect a cable free computer network. It allows the sharing of information between any validated user of the system. The system uses an encrypted and possible frequency hopping transmission to send and receive information in real time. A number of Tornado F.3 airframes have been modified to allow them to partake within the network.
A valid user of the JTIDS system may be an AWACS aircraft, another F.3 or a ground station of some kind. It enables a higher state of situational awareness to be maintained and to ensure that other components of a combined attack force all have the same information.