General Atomics is to relaunch production of the Dornier 228 twin-turboprop with the first example to roll off the Oberpfaffenhofen final assembly line in 2024.

Separately, the manufacturer is working with MTU Aero Engines and German aerospace research centre DLR to develop a hydrogen fuel cell powertrain for the type.

Aurigny Dornier 228 in flight

Source: Aurigny

Do 228 remains popular with niche carriers

Better known for the unmanned air vehicles (UAVs) such as the MQ-1B Predator produced by its aeronautical systems business, General Atomics acquired the Do 228 programme as part of its March 2021 purchase of RUAG Aerospace Services.

But Harald Robl, managing director of General Atomics Europe and General Atomics AeroTec – the unit in which the Do 228 resides – describes the legacy 19-seat turboprop as a “favourable product” for the market. “We have a big volume of interest and [customer] requests,” he says.

Sales to military/special mission and niche passenger operators are on the cards, although General Atomics is not yet “taking binding orders” for the aircraft, he said at the ILA Berlin show earlier this week.

No major changes to the Do 228’s design are contemplated, says Robl, but the restart of production will deal with “obsolescence issues” on the type.

Separately, the company has provided a Do 228 to the DLR and MTU for the fuel cell conversion project. This will see the left-hand stock Honeywell TPE331 turboprop engine replaced with a 600kW electric motor powered by a hydrogen fuel cell system. First flight is expected in 2025.

General Atomics is not alone in using the Do 228 as a fuel cell testbed, however: ZeroAvia is also converting a pair of the aircraft to test its 600kW ZA600 powertrain.

While ZeroAvia intends to use gaseous hydrogen stored in external tanks, the MTU/DLR design stores the liquid fuel inside the fuselage.

the-new-dlr-do-228-d-cefd-research-aircraft

Source: DLR

MTU and the DLR are collaborating on Do 228 fuel cell conversion

“We already have customer interest for the aircraft,” adds Robl. “The concept seems to me really outstanding.”

However, he points out that General Atomics is only supporting the MTU/DLR effort.

He says there is no decision yet on whether to offer the system as a line-fit or retrofit option via a supplemental type certificate and will make that selection together with customers. Service entry could come in the 2027-2028 timeframe, he adds.

One of the reasons for General Atomics’ acquisition of the RUAG business was to provide it with a European maintenance and overhaul facility for operators of its UAVs, not least that the MQ-9 Reaper and Do 228 share a common engine.

Robl sees potential for further co-operation between the two arms of the company, potentially introducing manned-unmanned teaming capability to the Do 228 or using the flight control expertise in General Atomics Aeronautical Systems (GA-ASI) to develop a single-pilot or eventually unpiloted cargo variant.

Initial concept studies have already begun, in tandem with work to address regulatory barriers to single-pilot operations, he adds.

Meanwhile, GA-ASI is seeing increased interest in the SeaGuardian, the maritime variant of its new MQ-9B SkyGuardian UAV.

European customers for the SkyGuardian include Belgium and the UK, with “a full expectation” that the latter is likely to eventually equip some of its up to 16-strong fleet with a maritime radar, says Scott Smith, regional vice-president, international strategic development. That will happen “sooner rather than later”, he says.

Additionally, GA-ASI is contemplating the integration of Kongsberg’s 407kg (897lb) Naval Strike Missile (NSM) onto the MQ-9B following customer interest. “It is capable of carrying it,” adds Smith.

MQ-9B in RAF 31 Sqn markings

Source: Mark Kwiatkowski

UK Royal Air Force will operate the MQ-9B SkyGuardian under the name Protector RG1