Billions of pounds allocated to upgrading the Royal Air Force’s ageing fleet of E-3D Sentry aircraft could be better spent purchasing a more advanced off-the-shelf aircraft, a leading industry analyst has argued.

The RAF has begun a long-overdue capability sustainment programme (CSP) for its fleet of six E-3D Airborne Warning and Control System (AWACS) aircraft, which is likely to run through to 2025 and will see the aircraft operate for at least another 15 years.

The upgrades will finally bring the UK’s fleet of E-3D’s up to the standard of both the US Air Force’s E-3G and French Air Force’s E-3F, both of which operate the modernised Block 40/45 standard.

According to Justin Bronk, a research analyst with the Royal United Services Institute (RUSI), the estimated £2 billion upgrade programme will not address key capability shortfalls of the AWACS, including those associated with the distinctive mechanically scanned radar that sits atop the fuselage.

‘Because of the limitations of the mechanically scanned radar, [the AWACS] has significant blind spots against emerging threat groups such as hyper sonic weapons, and low observable weapons and fighters,’ he explained to Shephard.

‘[And] because long range surface to air missiles systems and even fifth generation fighters are proliferating so rapidly, things like AWACS and aerial refuelling aircraft will have to stay so much further back from the battlespace,’ he added.

For Bronk there are more ‘efficient options’ on the table that utilise commercial airframes, including the Boeing 737 or Airbus A330 airliners, and more powerful active electronically scanned array (AESA) radar systems that offer superior range and detection capabilities than the E-3D’s existing AN/APY-1/ 2.

‘With the amount of power you can now put through a large AESA array, coupled with modern processing capabilities, it really is a different ballgame in terms of situational awareness compared to E-3,’ he said, singling out technology such as Saab’s Erieye radar system.

Bronk said buying a new fleet of AWACS aircraft - based on a commercial off-the-shelf aircraft - was feasible as a similar amount of money allocated to the CSP had been spent on purchasing nine advanced P-8 Poseidon maritime patrol aircraft from the US.

That would provide a suitably advanced capability to address future threats until the US Air Force introduced its own replacement E3 platform in the 2035-40 timeframe.

‘We are going to need something for those 20-25 years,’ he told Shephard. ‘And for me that would justify the investment to buy some sort of new AWACS and air C2 capacity, off-the-shelf if needs be, or even a developmental one.

‘You look at P-8, it is obviously a different aircraft, but it is similarly sized, very electronically complex, off-the-shelf buy and including all the set up costs, it comes to £2.4 billion, that’s for nine aircraft.’

Bronk explained that the current E-3D availability is somewhere between zero and two on a given day, so a modern system that is proven and off-the-shelf could mean a procurement of less than six initially to replicate at least that level of availability.

Last year, the UK’s AWACs fleet was temporarily taken out of service due to wiring issues found with the aircraft. The fleet returned to operational duties at the beginning of the year when the wiring problems were rectified.