Deployable air traffic control – from off the radar to off the shelf

Derailed by major budget cuts in 2011, the US Air Force's Deployable Radar Approach Control (D-RAPCON) system is back on track. Dr Gareth Evans reports on how the decision to adopt a more commercial-off-the-shelf (COTS) approach to procurement has revived the concept of deployable mobile air traffic for use in conflict and natural disaster missions.


This new mobile air traffic management system is intended to be used at forward operating locations, either early on in a conflict, or in the immediate wake of a natural disaster, to provide sequencing, separation of aircraft, navigation assistance and airspace control services. In addition to meeting the demands of war-fighting or emergency humanitarian aid in a minimal-infrastructure environment, it could also be used to provide a fast back-up for failed military or civilian fixed installations.

"The Department of Defense hope that the open competition, best-value contract will attract a range of bidders."

As the then programme manager, Captain Charles O'Connor, commented in mid-March when the project's reprieve was announced: "D-RAPCON will be a huge advancement for the user as it will be infinitely better than the legacy systems, which have been in the inventory for decades."

Advantages may be clear, but getting things moving again after Congress cut $48m from the programme's 2012 engineering, manufacturing and development budget required what O'Connor described as a 'regroup'. Captain Annette Boender, who succeeded him in the role after his recent deployment, says that meant a significant rethink for the programme office, working in conjunction with the Air Force Flight Standards Agency.

"By reducing capabilities where possible, encouraging the use of COTS products, and reducing the pre-production units from two to one, the programme was able to fit within the budget, while maintaining the original concept of operations."

Commercial-off-the-shelf benefits for military applications

That calls for a scalable, modular system, with 60-mile coverage, which can be deployed within 48 hours, is air-portable by up to four C-130 cargo aircraft and once on-site, can be operational within 24 hours. D-RAPCON will comprise of two sub-systems - air surveillance radar and operations - and each is required to be deployable separately, to provide the flexibility to replace an inoperative fixed control tower or radar system independently, if the need arises. In addition, the system will need to come with its own back-up power and all required essential equipment as a stand-alone.

"Utilising COTS solutions means cost savings for the programme because potential vendors do not need to build new products. Instead, they can use products that already exist in their inventories, as long as those products meet the programme's key performance parameters," says Captain Boender.

It is a point broadly echoed by Raytheon - one of those offering a D-RAPCON solution. "The key benefits of using a COTS approach are lower cost, lower technical risk and faster delivery. On the flipside greater attention must be paid to equipment protection - for example, shock isolation mounting - and implementing robust environmental conditioning at the system design phase, as COTS equipments are not designed to operate in severe conditions."

Raytheon's game changer

Raytheon highlighted its D-RAPCON solution - described by Mike Prout, VP for Network Centric Systems' Security and Transportation Systems, as a "game changer when it comes to safe, modern, deployable air traffic control" at the Air Traffic Control Association Annual Exposition in October 2011.

"Whichever company proves successful, it remains clear that D-RAPCON will represent a massive improvement on ageing legacy systems."

The whole system package consists of the radar antenna itself and three trailers, containing all the communications equipment, environmental control and power units required to be fully operational and controlling air traffic within six hours of unloading.

It is based around their established ASR-11 digital airport surveillance radar (DASR) and standard terminal automation replacement system (STARS), and according to the company, the presence of these systems on current US military inventories could be a factor in their favour.

"As there will be over 200 sites containing our DASRs with existing support facilities - training, maintenance, logistics, obsolescence management and so on - there are many strong economic and technical advantages in maintaining commonality with the deployable systems. In addition the DASR system is already certified to operate in the US National Air Space. It's a lengthy and costly certification process."

Lockheed Martin and ARINC enter the fray

With the USAF planning to purchase 19 D-RAPCON systems and an overall programme value estimated at $672.5m, Raytheon are not the only contenders for the $50.5m engineering, manufacturing and development contract which is due to be awarded in early 2013.

Lockheed Martin and ARINC Incorporated originally teamed up in 2010 to provide proven technology for D-RAPCON as it stood then, and inevitably the renewed focus on COTS solutions in the wake of the recent programme 'regrouping' has lent additional impetus to their collaboration.

Lockheed spokesperson, Chip Eschenfelder, explains: "Lockheed Martin intends to offer a version of its TPS-79 tactical surveillance radar and Federal Aviation Administration-certified air traffic management software.

"ARINC, well known around the world for its transportable command and control systems, will provide the D-RAPCON transportable air traffic control operations shelter. As long-term leaders in the aviation industry, Lockheed Martin and ARINC specifically bring more than 50 years of tactical radar and air traffic control innovation to this project."

COTS advantages and timeframe questions

"D-RAPCON will comprise of two sub-systems - air surveillance radar and operations - and each is required to be deployable separately."

Aside from reducing the technical risk, adopting proven solutions for D-RAPCON, the COTS route also brings obvious benefits in terms of speed of delivery. Although the programme is currently scheduled to achieve full operational capacity in 2020, the US Air Force might wish to speed up that timeframe - something which Raytheon feel fits in well with today's budgetary constraints.

"We have encouraged the USAF to accelerate the programme if possible, as a higher production rate over a shorter period of time will have economic advantages. As our major sub systems are already certified and are in current production, we estimate the programme could be completed within a four year period."

Whether that will be a route that the USAF will choose to explore remains to be seen, as it seems adjusting the previous system requirements documentation has already proven an unexpectedly lengthy process.

An industry day was held in early March to highlight the post-regrouping differences, but according to Captain Boender: "The D-RAPCON RFP [request for proposal] was scheduled for release at the end of March, but longer than anticipated document review and coordination has slipped the RFP release date, which is now planned to be in May."

The Department of Defense hope that the open competition, best-value contract will attract a range of bidders. Whichever company ultimately proves successful, it remains clear that D-RAPCON will represent a massive improvement on ageing legacy systems - first fielded in the 1970s - as well as providing a major boost to future disaster relief operations.

As Colonel Jimmie Schuman, Aerospace Management Systems senior materiel leader, said back in March: "We have seen recently with the earthquake in Haiti and previously with Hurricane Katrina, this humanitarian relief aspect will fill a critical need."