The Interstate Aviation Committee (MAK), the CIS aviation registration body, has warned Ukrainian aircraft-engine maker Ivchenko-Progress and the Antonov aircraft company about possible serious defects in the D-436-148 turbofan which powers the Antonov An-148 airliner, Kommersant-Ukraina reported on Tuesday.
MAK has warned it may stop the An-148 flying in Russia if the deficiencies are not fixed.
MAK’s head Alexander Donchenko wrote to Antonov and Ivchenko-Progress on July 17, the paper says, warning of “serious incidents connected to failures of the engine installed in the An-148-100 which have taken place recently. Preliminarily, this is a a failure of the central drive-gear in the gearbox and failure of the engine bearing,” he wrote.
MAK insists the manufacturer takes action to fix the aircraft and engine so that the problem is not repeated.
If “the manufacturers do not take remedial action to fix these faults in the shortest time, MAK will, in accordance with international certification practice, issue a directive on limitation of the aircraft’s flight worthiness,” the watchdog said. That would mean the aircraft would be prevented from flying in Russia until the faults were fixed.
Ivchenko-Progress’ chief designer Igor Kravchenko told Kommersant-Ukraine he had not received any letter from MAK. “I can only say that the reliability indicators for the D-436-148 engine completely comply with the existing normative indicators. There is no totally reliable equipment, and there are problems for everyone. However, all engines in the world have defined reliability indicators and we we meet those norms,” he said.
Russian leasing company Ilyushin Finance Company, which promotes the An-148 (including on the Russian market), described the situation as normal.
“New equipment always needs corrections,” said Ilyushin Finance’s press secretary Andrei Lipovetsky. “The An-148 is a new aircraft and there are not many flying. A plan has been worked out for quickly replacing a few components, in particular the engine bearings. This should not affect the operation of the aircraft,” he added. He claimed there had been no safety incidents connected with technical failures related to the problems in question, and the issues had only been discovered when engines had been returned to the factory for overhaul.
“The bearings in question are made in Samara and are not only in engines made by Motor-Sich [another Ukrainian engine-maker],” he said.
In September 2010, GTK Rossiya, which operated five An-148s, criticized the aircraft over its poor reliability which it described as “below the previously declared level, and not enough to provide safe and regular flights.”
An An-148 crashed during a test-flight in March 2011, killing six on board. The investigation into the accident blame a faulty airspeed indicator, which caused the pilots to dive the plane to pick up speed, resulting in an overspeed and subsequent structural failure.
Ukrainian companies were reported to be developing a new-generation engine, the 12 MW-rated AI-28, for the An-148 family, in conjunction with Russia under a bilateral agreement.
The An-148 is a short-range twin-turbofan powered regional airliner carrying from 68-85 passengers from 2,000-7,000 km.