Diesel piston pioneer Thielert Aircraft Engines, insolvent since April, is building engines again, but the battle of wills with its biggest customer Diamond Aircraft continues.

Although production of the Centurion 2.0 has resumed at the German company's Lichtenstein factory, Diamond has yet to agree a deal for deliveries of new engines.

The Austrian airframer's piston-single DA40 and DA42 twin are the only original equipment applications for the powerplant, but - apart from some Lycoming avgas-powered variants of the DA40 - the production lines have been idle since TAE went into insolvency, despite orders for hundreds of aircraft.

Under German law, TAE's interim insolvency ends on 30 June, after which government support for employee wages will stop and the company will enter an "open" insolvency period.

Insolvency administrator Bruno Kübler was this week due to approach "more than 50 prospective buyers" before drawing up a shortlist of candidates "capable of securing the existence of the company on a long-term basis".

Diamond, which last month insisted it had no interest in purchasing Thielert, says it has "formally registered as a potential investor", but has not been approached by Kübler.

Meanwhile, Diamond is pressing ahead with plans to certificate its own Austro diesel engine for its DA40, DA42 and new DA50 aircraft, and is pursuing US and Canadian approval to fit Lycoming IO-360 avgas engines both on new-build and on existing TAE-powered DA42s for the North American training market.

Kübler says TAE is able to produce up to 80 engines a month, "almost as many as before being forced to apply for insolvency proceedings".

In a statement, Diamond says "the TAE insolvency continues to present significant challenges to our customers, our business partners and Diamond Aircraft".

Source: Flight International