Updated: April 2012

When you read about the Eurofighter Typhoon you read about Tranches, Blocks, Phase Enhancements and Change Proposals but what does it all mean?

To understand the Typhoon programme you have to first look at a brief history of Typhoon.

History

In 1979 British Aerospace and Messerschmitt-Bolkow-Blohm produced a proposal to meet the needs of both the British RAF and West German Luftwaffe for a Cold War air supremacy fighter.

Between 1979 and 1986 (when the first prototype took to the air) the partner nations tried to reach agreement over specification, requirements and how to approach the project. This saw the name of the project change from European Combat Fighter to European Combat Aircraft to Agile Combat Aircraft to Future European Fighter Aircraft and finally being called European Fighter Aircraft.

The programme would see the Italians along with the Spanish join and the French join then leave, twice!

The 1990s saw arguments, politics and negotiation around the radar supplier and how the work should be shared between the four countries. With the Berlin Wall coming down, the end of the Cold War and the scaling back of defence budgets the partner nations reduced the number of aircraft they would commit to.

The Germans would make the biggest cut, reducing from 250 down to 140 before raising it up to 180 after lengthy negotiation to limit the associated impact to their share of the industrial contracts to build the aircraft.

Further delays to the project would occur in the late 90s with the Germans still struggling with the cost of the reunification. They would delay making their payment for the construction phase, putting back the project by a year.

Type acceptance for Typhoon finally came on 30th June 2003 four year after originally planned and the first delivery was made to the German Luftwaffe on 4th August 2003.

In 2003, Austria became the first export customer for Eurofighter with an order for 15 Typhoons. Delivery began in July 2007 and the first operational air policing missions began in June 2008. Their final Typhoon was delivered in September 2009.

Saudi Arabia became the second export customer in September 2009 with an order for 72 Typhoons. 24 of these will be diverted from the RAF’s Tranche 2 production and it is planned for the other 48 to be locally assembled (although this now may be in doubt). Their first aircraft was delivered in June 2009.

Production for 2010 was 50 Typhoons a year and the 250^th Typhoon was delivered to the Italian Air Force in December 2010.

Tranches

With a number of different nations involved in a project as large as this, all with an equal say, there was always going to be disagreement, delays and a lot of politics. In an attempt to make reaching agreement easier Typhoon would be produced in three tranches.

Each tranche is a separate contract between the partner nations and Eurofighter GmbH for an agreed number of aircraft. This would allow the partner nations the flexibility to change the number of aircraft they order over the construction period but at the cost of having to pay compensation to Eurofighter GmbH to assure construction and development continues without an increase to the unit price for the other partner nations.

Whilst the three tranches are financial divisions it also allows specification changes to the aircraft from the framework laid out at the start. This allows new features to be added or deleted as required even at an individual nation level.

Eurofighter Typhoon Tranche 1 Block 1

Blocks

Where the tranche is a financial division, the block is a level of capability. With each new block new capabilities are introduced. The block approach is a common method used for military aircraft to roll out hardware upgrades, software upgrades, new hardware and / or structure change.

Typhoon was originally planned to have three blocks per tranche (with Tranche 3 containing Block 20, Block 25 and an option for another block). Each block was to build on the previous one with Tranche 1 covering air-to-air capabilities, Tranche 2 to introduce new weapons such as the Meteor BVR missile and Tranche 3 for future capabilities such as the AESA radar and thrust vectoring

Enhanced Operational Capability 1 & 2 (EOC-1 & EOC-2)

The development plan was at Block 5 (the final block in Tranche 1) Typhoon would be at Full Operational Capability (FOC). By Block 10 (the penultimate block in Tranche 2) it would be Enhanced Operational Capability 1 (EOC-1) and Block 15 (the final block in Tranche 2) it would be EOC-2. The development plan for Block 20 / Block 25 in Tranche 3 was to be left open.

These plans were drawn up in the Cold War when Typhoon’s primary role was intended to be as an air supremacy fighter operating over Western Europe fighting against Soviet MiGs and Sukhois. With the fall of the Soviet Union this threat was no longer present and new requirements in Iraq and Afghanistan had replaced it which needed an air-to-ground capability.

Eurofighter Typhoon Trance 1 Block 5

Change Proposal 210 (CP-210)

In 2007, the partner nations responded to his change of requirement with Change Proposal 210 which approved changes to Typhoon to give it an air-to-ground capability. This would change Typhoon from an air supremacy fighter to a swing-role fighter capable of performing both the air-to-air role and air-to-ground role.

CP-210 will be introduced in Tranche 2 and will be retro fitted to Tranche 1 aircraft.

Change Proposal 193 (CP-193)

The RAF had at the time Tornado GR4s deployed to Iraq and Harriers deployed to Afghanistan both providing close air support to troops on the ground. The RAF needed Typhoon to have an air-to-ground capability before Tranche 2 started delivery with CP-210. In July 2006, under CP-193 an “austere” air-to-ground capability was rapidly developed and deployed to Trance 1 Block 5 Typhoons. The austere support also provided integration of Litening III, the chosen Laser Designator Pod, and laser guide munitions in the form of Paveway II / Enhanced Paveway II. The RAF changed the designation of these Typhoons from F2 to FGR4 to denote the ground attack and recon role as well as the fighter role.

The first Paveway II was dropped on 12^th November 2007 by a combined BAE and RAF test team and the Typhoon was declared multi role capable on 7^th July 2008. On the 12th May 2011 the RAF’s Typhoons put the austere air-to-ground capability to use as part of OP ELLAMY, the UK’s contribution to enforcing the UN Security Council Resolution 1973 over Libya, when a Typhoon destroyed two main battle tanks near Misrata with a Paveway II.

This has created a strange situation where Tranche 1 Block 5 aircraft have both air-to-air and limited air-to-ground capability whilst newer Tranche 2 Block 8 aircraft with over 400 improvements over Tranche 1 aircraft only have air-to-air capability.

The crux of the problem is software. The modification to the Typhoons software made by CP-193 was outside the development path. If they continued with two development paths (one with CP-193 for the RAF and one without for the other nations) you would need to develop and flight test both versions of the software with the RAF picking up the bill for the duplication of work.

By getting all nations to agree to include air-to-ground capability (CP-210) the RAF and Eurofighter GmbH had managed to bring this software modification into the main development path of the software but not soon enough to have it include in Block 8.

Eurofighter Typhoon Trance 1 Block 5 with LITENING III pod

Phase 1 Enhancements (P1E) Phase 2 Enhancements (P2E)

With the change to a swing-role fighter the development plan defined in EOC-1 and EOC-2 no longer matched where the development of the aircraft was heading. To this end, both were replaced with Phase 1 Enhancement (P1E) and Phase 2 Enhancement (P2E) respectively.

P1E was signed off in 2007 and contains the CP-210 modification. Flight testing has begun on P1E and it is scheduled to reach service release in 2011.

P2E was very short lived and has now been abandoned in favour of individual modifications similar to the method used for CP-193 and CP-210. This will allow a more granular approach and avoid having to get agreement from all partner nations for a large package of changes.

Software Releases – SRPs

Once a Typhoon has reached P1E standard it will be running software release SRP 10; providing initial Paveway IV capability. Further capability will be released by later versions of the software.

SRP 12 will add full integration of Paveway IV and the ability to attack multiple ground targets with a single attack run. SRP12 is expected to be release in 2012.

SRP 14 will further increase the available weapons with Storm Shadow, Brimstone and initial Meteor capability expected.

SRP 16 is expected to deliver full Meteor capability.

SRP 18 is expected to integrate the AESA radar.

Less Blocks

With features being employed individually the need for a block with a defined capability no longer existed. Tranche 2 Block 8 / 8B (the current production level) will be the last defined block.

The RAF has committed to have a standardised fleet and the Tranche 1 Typhoons are undergoing R2 upgrades to retrofit them to the latest standard (Block 5). The process takes 7 months for Block 2 aircraft and 12 months for Block 1 aircraft and the halfway point was passed in early June 2010 with 22 of the 43 aircraft complete.

All Tranche 1 aircraft will be upgraded to Tranche 1 Block 5 with P1E.

All Tranche 2 aircraft will be Block 8 with P1E.

This will give all the aircraft full air-to-air capability, full air-to-ground capability and the ability to perform both these roles simultaneously.

There will be no upgrades from Tranche 1 to Tranche 2 due to the physical differences between the two builds.

Eurofighter Typhoon Trance 2 Block 8

Tranche 3

With pressure increasing on defence budgets, especially for the British MoD who had a £36 billion pound funding black hole, Tranche 3 was under a very real threat of being cancelled.

The partner nations, in particular Germany, applied pressure on the British Government to sign the contract but the British insisted that costs must be reduced before they would do that.

To help the situation the tranche was broken into two parts, Tranche 3A and 3B.

A breakthrough was finally made with the British agreeing to take their full allocation of 40 Tranche 3A Typhoons in exchange for £900 million worth of savings achieved from reductions to the support contracts by BAE, Rolls-Royce and other partners.

Tranche 3A is due to start being delivered in 2013 and complete in 2016.The exact specification of Tranche 3A isn’t known at the time of writing as it is still being negotiated (the Tranche 3A contract signed only agrees to the production of a Tranche 3A not the capability of those aircraft) but it is expected they will be based on Tranche 2 with phased upgrades being included from 2014.

The British MoD has stated that with the signing of the contract for the production of Trance 3A the programme had reached the financial ceiling as agreed in the Memorandum of Understanding (MoU) and therefore had no further obligation to purchase their allocation of Tranche 3B Typhoons. Eurofighter GmbH at the time said this would be a matter for the partner nations to discuss and in May 2010 submitted a proposal to the partner nations for the 124 Tranche 3B Typhoons. Eurofighter GmbH hopes to have a decision by 2012 allowing them to keep production going.

If the partner nations do not take their allocation the future of Trance 3B looks bleak. The British haven’t totally ruled out making further purchases of Typhoons, instead saying they are unlikely to do so but reserve the right. The Italian Defence Minister said in July 2010 that they would be cutting their order by 25 aircraft, representing the Italians allocation of Tranche 3B aircraft.

BAE Systems have said they have forecast the Tranche 3B not being signed on time in their financial projection released in 2011. Without Tranche 3B to keep the production lines open Eurofighter GmbH must attract more export customers or sell more Typhoons to the current export customers. There is little chance of Austria purchasing more Typhoons but Saudi Arabia does have an option for a further 24 Typhoons. The purchase of 84 F-15S fighters has put this in doubt making new export customers the best option.

In May 2010 a proposal was put forward to reduce the delivery rate of the Typhoon to the partner nations to give the Eurofighter consortium the capacity needed to be able to produce Typhoons for export customers rather than divert Typhoons from partner nations as has happened so far. The proposal was agreed in July 2011 by all four partner nations and deliveries will be reduced to 43 from 53 for 2012 and a similar number for 2013. This reduction in delivery rate will also extend production for two more years allowing more time for export customers to be found. The French have already adopted this strategy for the Rafale and reduced production to just 11 aircraft a year whilst it attempts to find its first export customer.

With both the Rafale and Typhoon looking for export customers it’s not a surprise that they end up competing against each other and both aircraft have made it down to the final shortlist for the India Air Force’s MMRCA competition. The winner will get a $10.5 billion contract to provide 126 aircraft to the Indian Air Force. As well as providing work for the production lines this contract would also help fund the continuing development of the fighters, which would in turn help win further contracts.

Dassault’s Rafale was given preferred bidder status after winning the MMRCA competition on 31^st January 2012. This doesn’t mean Dassault has got the contract yet rather it now makes it Dassault’s deal to lose and they will be trying very hard to make sure that doesn’t happen. Dassault was awarded the status after submitting a lower cost in the sealed bid process. The actual figures aren’t publically available but without an export customer and a large portion of the French Air Force’s budget committed to keeping the Rafale production line open I suspect they were prepared to cut their profit margin more than Eurofighter.

The Rafale had also scored well in the technical evaluation for the MMRCA competition and its EW capability, sensor fusion and ability to attack more than one ground target in an attack run in particular. Typhoon will need to reach SRP 12 before it can attack multiple ground targets. SRP 10 was due in 2011 and SRP 12 in 2012 but to my knowledge no production aircraft have yet received SRP 10.

Eurofighter also missed out on the $6 billion order to provide 40 to 50 fighters to the Japan Air Self-Defense Force. After spending a number of years trying to get the US to export the F-22 Raptor without success the Japanese considered the Super Hornet, Typhoon or F-35 as replacement to their aging F-4EJ and RF-4EJ fighters. They opted to go for the F-35. With the Chinese developing a ‘fifth generation’ fighter the Japanese felt they needed to purchase the most advanced aircraft available but with the first four not being delivered until 2016 they are waiting a long time for them (assuming no more delays to the troubled F-35 programme).

There also a number of smaller competitions (all the export contracts they are involved in are listed below). These include a surprise request for information from UAE. Dassault was thought to have secured the contract with the UAE for 60 Rafales to replace their Mirage 2000-9 aircraft after years of negotiation. The UAE was expected to sign the contract at the 2011 Dubai Airshow but instead requested information from the UK government about the Typhoon and made a similar request to the US government about the Super Horner and F-15E.

Export Contracts Eurofighter Are Competing For

India

United Arab Emirates (UAE)

South Korea

Qatar

Oman

Malaysia

Future Upgrades

An important part of attracting export customers is to adopt cutting edge technology into Typhoon. Whilst Typhoon fairs well against current competitors it will soon be fighting against the F-35 for export customers and further upgrades will be required to keep it competitive.

The current possible developments to the Typhoon are the AESA radar, TVR engines and CFTs.

AESA (Advanced Electronically Scanned Array) Radar

The CAPTOR-M radar in Typhoon is a mechanical radar that physically moves to scan (M-SCAN). Electronically scanning (E-SCAN) radars are rapidly improving and appear to be the future of radar design.

Tranche 3A aircraft have the structure, power and cooling requirements to support its addition. Tranche 2 aircraft only have the structural requirements meaning that a retrofit program would be needed to support its addition.

Eurofighter Development Aircraft 5 (DA5) has already flown with an AESA radar in May 2007; using the AESA front end and the CAPTOR-M back end and referred to as CAESAR. Full scale development of the AESA radar has begun and the in service date is 2015 for both partner nations and export customers. The radar being produced by Euroradar is a multi-national consortium led by SELEX Galileo. SELEX Galileo are currently developing the AESA radar for the Saab Gripen NG.

Separate to this development program the UK have funded a technology demonstrator program under the name Bright Adder. It will also be in partnership with SELEX Galileo and will concentrate on the UK’s requirements for an AESA radar system such as the electronic attack feature that is currently provided by the Alarm missile on the Tornado GR4. When both the GR4 and the Alarm have been withdrawn from service the UK needs the Typhoon to have the capabilities to carry out the missions that both of these currently perform. SELEX has made a press release that says the demonstrator will fly in 2013 and confirmed the service entry date as 2015.

Conformal Fuel Tanks (CFT)

Like other fighter aircraft Typhoon is capable of using external (drop) tanks to increase its fuel capacity. These tanks can be fitted to the three wet points located on the fuselage centre point and the middle point on both wings. The addition of these tanks do bring a number of drawbacks. The loss of the two wing points means less points to attach ordinance and the centre point is also used to attach a targeting pod. The tanks also increase drag; although Typhoon is still capable of going supersonic with all three tanks fitted (tested to Mach 1.6 with three 1000 litre tanks).

Conformal Fuel Tanks would offer a solution to this problem with two semi-permanent tanks grafted onto the fuselage, each offering 1500 litres of fuel, without the loss of any points and reduced levels of drag. You will have seen them used on the F-15E Strike Eagle and starting to be seen more commonly on F-16s.

At present only Britain has shown interest in having CFTs. BAE have tested a scale model in a wind tunnel and are working on development with GKN Engage.

Eurofighter Typhoon Trance 1 Block 2B with three 1000 litre drop tanks

3D Thrust Vectoring Control (TVC)

Thrust Vectoring Control allows the nozzle on the engine to be deflected to enhance the agility of the fighter. With 3D TVC the nozzles are able to move up, down, left and right or a combination e.g. up and left.

No partner nation has expressed an interested in having TVC. Eurojet, the consortium of companies that produces the engines for Typhoon, is hoping to attract support for TVC by concentrating on the benefits provided above the enhanced agility.

Eurojet has said TVC would decrease fuel burn, increase the life of hot running components and reduce take off distance (particularly useful in ‘hot and high’ environments).

Eurofighter Typhoon Trance 1 Block 5

Other Planned Changes

Above are the major upgrades that are being considered for the near future. Other upgrades are also being considered and explored but on a lower priority.

Leading Edge Root Extension (LERX)

LERX is a common modification to fighter aircraft. It is a triangular shape that fits to where the wing and the body of the aircraft meet (anyone who is familiar with the Harrier GR7 to GR9 upgrade will have seen it) and is designed to control the airflow over the wing. By generating a vortex on the top of the wing air can be flowed under the wing causing an increase in lift. In high angle of attack manoeuvres this allows keeps the air flowing over the wing past the normal point an aerodynamic stall would occur. This offers an advantage in dog fights.

The developed Typhoon DA5 flew with LERX fitted between Sept and Oct 2007 but no further developed has occurred since.

Laser Designator Pod (LDP) Position

The LDP is currently fitted to the centre position on the Typhoon but on the Eurofighter 2020 illustration the LDP is shown fitted on the front left of the fuselage (in a similar position to where the F-16 has its LDP).

The current position of the LDP may be due to the “austere” nature of the air to ground capability introduced by CP193. When the full air to ground capability is introduced we might see the LDP move freeing up the centre position for either a drop tank or a weapon.

Passive Missile Warning

The Eurofighter 2020 illustration also has Passive Missile Warning with a pointer to the rear of the Typhoon. The PIRATE has a Passive Missile Warning capability but of course this is forward looking so it would appear they are considering a rear looking Passive Missile Warning capability for the Typhoon.