impossible!!!
In Tranche 1 machines, all microprocessors are of the Motorola 68020 type, which is called a General Purpose Processor (GPP). In these LRU computers, the application software can only work with this one specific hardware of the respective mission computer, which can make changes difficult or impossible.
Tranche 1 aircraft, on the other hand, can and will only be improved to a limited extent through software updates (drops). A solution to the Tranche 1 obsolescence problem is currently not in sight.
In short, if you have Tranche 1, then you have a problem!!! a big problem!!!
Bringing a Tranche 1 to a Tranche 2 means rebuilding the aircraft completely.
In contrast to the F-22 and Rafale F2/3, the Eurofighter does not yet use integrated modular avionics (IMA). While in both cases all sensor data is fed into a central data processing system, in the Typhoon the sensor data is processed by several subsystems in order to be combined to form an overall tactical picture of the situation. The avionics consists of several computers that are linked via fiber optic cables according to STANAG 3910 and can transmit up to 1,000 Mbit/s. Individual systems also represent "islands" in the avionics and are only connected to the fiber optic network via another computer. The subsystems of the Praetorian system, the friend-or-foe query systems, the basic aircraft systems, the weapons control system and the cockpit subsystems are linked via MIL-STD-1553 data buses, which are designed for a lower data throughput of 100 Mbit/s. In addition to the local air cooling of individual components, the waste heat from the avionics and the anti-G suit is transferred via liquid cooling circuits to the fuel, which serves as a heat sink. The entire software of the Eurofighter is written in Ada. At the time of project development, the Eurofighter was the largest Ada software project in Europe.
For Tranche 2 aircraft, the avionics were completely overhauled according to ASAAC, i.e. a strict separation of a function in hardware and software. EADS began developing IMA on a COTS basis according to the ASAAC standard for aircraft such as the Eurofighter before 2001.
The core element of this Universal Aircraft Computer (UAC) was the separation between hardware, hardware abstraction layer (HAL), operating system and application software (apps). In contrast to the Rafale, which switched directly to IMA for F2, the original avionics architecture was retained for the Eurofighter's Tranche 2 to reduce risk, but the computing modules were standardized and a uniform real-time operating system (OS) was chosen for all mission computers with Integrity-178B. Hardware, HAL and OS are the same for all LRIs, only the apps differ depending on the mission computer's area of application. For communication between the computers, each LRI has a Common EFEX Module (CEM), which serves as an intermediary between the ASAAC standard and real Eurofighter technology. ASAAC works with packet switching, whereas EFEX uses a predefined transmission table. The Eurofighter's apps/mission computers communicate with a type of mailbox system and store the mail in the target computer, while the information is sent to ASAAC via virtual channels. Furthermore, each LRI has three Common Processing Modules (CPM) which run the application software on the OS. All four modules of the LRI are connected via a VMEbus backplane. The LRIs are supplied by Rockwell Collins, for example, correspond to the 1/2 ATR standard, are air-cooled, have six slots and can provide up to 250 W. The three processor cards have dual/quad-core processors and PCI mezzanine cards with mass storage. If the VMEBus or EFEX is not sufficient, 10 GEth lines can be connected. IPA6 and IPA7 were used for the flight tests of the new avionics, which were required for international approval.
The Tranche 1 machines are limited in terms of software due to their limited computing power: for example, during a bombing mission it is possible to locate an air target using ESM/ECM and shoot at it using AMRAAM, but then it is no longer possible to switch to air-to-ground mode. This was only remedied in Tranche 2 by increasing computing power.
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